Projection device

Abstract

This disclosure provides a projection device, including: a housing, a light source assembly, and a projection lens. The projection device has an internal accommodating space. The projection device further includes: a second reflector, a second fan, and a lens assembly located within the accommodating space. The second reflector is disposed on the light-emitting side of the light source assembly and is used to reflect light emitted by the light source assembly into the lens assembly. The lens assembly is used to collimate the light. The accommodating space includes an airflow space, which includes a first subspace and a second subspace. The light source assembly, the second reflector, the lens assembly, and a portion of the housing define the first subspace, and the second subspace is located around the first subspace. The second fan is used to drive the internal air circulation within the airflow space, causing the internal air to circulate between the first subspace and the second subspace.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically to a projection device. Background Technology

[0002] A projection device is a device that projects images or videos onto a screen. It can be connected to devices such as computers, game consoles, and televisions through various interfaces to play corresponding video signals. Projection devices are widely used in homes, offices, schools, and entertainment venues.

[0003] Currently, the main projection devices on the market include CRT (Cathode Ray Tube) projectors, LCD (Liquid Crystal Display) projectors, and DLP (Digital Light Processing) projectors. LCD projectors mainly include single-LCD projectors and triple-LCD projectors. Single-LCD projectors have a simple structure and low cost, making them suitable for low- and middle-income consumers, and therefore have considerable growth potential. Summary of the Invention

[0004] This disclosure presents a projection device.

[0005] This disclosure provides a projection device, including: a housing, a light source assembly, and a projection lens. The projection device has an internal receiving space, and further includes: a second reflector, a second fan, and a lens assembly located within the receiving space. The second reflector is disposed on the light-emitting side of the light source assembly and is used to reflect the light emitted by the light source assembly into the lens assembly. The lens assembly is used to collimate the light.

[0006] The containment space includes an airflow space, which includes a first subspace and a second subspace. The first subspace is defined by the light source assembly, the second reflector, the lens assembly, and a portion of the housing, and the second subspace is located around the first subspace.

[0007] The second fan is used to drive the internal air circulation within the airflow space, so that the internal air circulates between the first subspace and the second subspace.

[0008] In some embodiments, the second fan includes a fan housing, the fan housing includes a functional area and a non-functional area, the functional area is provided with a second air inlet and a second air outlet, and the non-functional area is provided with a ventilation section that penetrates the fan housing;

[0009] The second air inlet faces the second subspace, and the second air outlet is configured to simultaneously discharge air into the first subspace and the second subspace;

[0010] The air discharged into the first subspace enters the second air inlet through the ventilation section; the air discharged into the second subspace flows within the second subspace and then enters the second air inlet.

[0011] In some embodiments, the housing further includes a third opening, at least a portion of which is located on the rear surface of the housing;

[0012] The projection device further includes a first heat sink located at the third opening; the light-emitting component, the projection lens, the first heat sink, and the housing together define the receiving space.

[0013] The second subspace includes: a first air duct located between the first radiator and the second fan, wherein at least a portion of the first radiator forms one side wall of the first air duct;

[0014] The air discharged from the second air outlet into the first subspace can pass through the ventilation section and the first air duct in sequence before entering the second air inlet.

[0015] In some embodiments, the second air inlet is disposed facing the first air duct.

[0016] In some embodiments, the projection device further includes a display panel and a first lens, the display panel being located on the side of the lens assembly away from the second reflector, and the first lens being located on the side of the display panel away from the lens assembly;

[0017] The lens assembly and the display panel have a second gap, and the first lens and the display panel have a third gap;

[0018] The second subspace also includes a U-shaped air duct, which includes a second air duct and a third air duct arranged side by side and interconnected. The second air duct includes a second gap, and the third air duct includes the third gap. The airflow path of the second air outlet into the second subspace includes the second air duct, the third air duct, and the first air duct.

[0019] In some embodiments, the second air outlet is disposed toward the second air duct, and the air discharged into the second subspace by the second air outlet passes through the second air duct, the third air duct and the first air duct in sequence before entering the second air inlet.

[0020] In some embodiments, along a direction perpendicular to the reflective surface of the second reflector, the projection of the second reflector onto the fan casing of the second fan does not overlap with at least a portion of the ventilation section.

[0021] In some embodiments, the reflective surface of the second reflector is trapezoidal, the trapezoid having a first base and a second base that are parallel to each other, and a waist connecting the first base and the second base. The length of the first base is greater than the length of the second base. The first base is located in the first subspace near the lens assembly, and the second base is located in the second subspace away from the lens assembly.

[0022] Along the direction perpendicular to the reflective surface of the second reflector, the projection of the waist of the trapezoid on the fan housing is in contact with or adjacent to the ventilation section.

[0023] In some embodiments, the ventilation portion is distributed on two waist sides of the second reflector; the ventilation portion includes a plurality of ventilation holes, and each waist side of the second reflector is provided with a plurality of ventilation holes.

[0024] In some embodiments, the second air outlet includes a first region and a second region, the second region being the region of the second air outlet opposite to the second subspace, and the first region being the remaining region of the second air outlet located on the side of the second region closer to the first subspace.

[0025] The area of ​​the first region is the first effective exhaust area, the area of ​​the second region is the second effective exhaust area, and the ratio of the ventilation area of ​​the ventilation section to the first effective exhaust area is within the range of [1, 1.3].

[0026] In some embodiments, the ratio of the ventilation area of ​​the ventilation section to the first effective exhaust area is in the range of [1.1, 1.3].

[0027] In some embodiments, the second air outlet includes a first region and a second region, the second region being the region of the second air outlet opposite to the second subspace, and the first region being the remaining region of the second air outlet located on the side of the second region closer to the first subspace; the area of ​​the first region is a first effective discharge area, and the area of ​​the second region is a second effective discharge area;

[0028] The ventilation area of ​​the second air inlet is M times the sum of the first effective exhaust area and the second effective exhaust area, where M is in the range of [1, 1.2].

[0029] In some embodiments, the second air outlet includes a first region and a second region, the second region being the region of the second air outlet opposite to the second subspace, and the first region being the remaining region of the second air outlet located on the side of the second region closer to the first subspace; the area of ​​the first region is a first effective discharge area, and the area of ​​the second region is a second effective discharge area;

[0030] The second effective discharge area is (1, 3) times the area of ​​the first effective discharge area.

[0031] In some embodiments, the lens assembly includes: a light-transmitting portion and a second lens, the light-transmitting portion being located on the side of the second lens away from the second reflector.

[0032] In some embodiments, the lens assembly is configured to divert the air discharged from the second air outlet, so that a portion of the air discharged from the second air outlet enters the first subspace, and a portion of the air discharged from the second air outlet enters the second subspace.

[0033] In some embodiments, the lens assembly includes: a light-transmitting portion and a second lens, the light-transmitting portion being located on the side of the second lens away from the second reflector;

[0034] The lens assembly further includes: a fixing member connected to the housing, the fixing member being disposed opposite to the second air outlet;

[0035] The edge of the light-transmitting part near the second air outlet and the edge of the second lens near the second air outlet are both limited by the fixing component.

[0036] In some embodiments, the second air outlet includes a first opening and a second opening, the first opening and the second opening are arranged side by side, and the length of the first opening is less than the length of the second opening;

[0037] Wherein, at least a portion of the first opening is configured to discharge air toward the first subspace, and at least a portion of the second opening is configured to discharge air toward the second subspace.

[0038] In some embodiments, the projection device further includes:

[0039] The first polarizing element is used to convert the light reflected by the second reflector into first polarized light with a first polarization direction;

[0040] The display panel is located on the side of the lens assembly away from the second reflector;

[0041] The first lens is located on the side of the display panel away from the lens assembly, or is disposed between the display panel and the first polarizing element;

[0042] The first reflector is configured to reflect light emitted from the display panel into the projection lens;

[0043] The second polarizing element is disposed on the side of the display panel away from the first polarizing element, and is used to emit one of the polarized light in the first polarization direction and the polarized light in the second polarization direction from the projection lens, wherein the first polarization direction is perpendicular to the second polarization direction.

[0044] The first reflector and the second polarizing element may be the same element or different elements; the display panel is a liquid crystal display panel. Attached Figure Description

[0045] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0046] Figure 1A , 1D Figures 1 and 1E show schematic perspective views of a projection apparatus according to some exemplary embodiments of the present disclosure in cross-section, intended to illustrate the internal structure of the projection apparatus.

[0047] Figure 1B and Figure 1C This is a schematic perspective view of a first heat sink of a projection device according to some exemplary embodiments of the present disclosure.

[0048] Figure 2 This is a schematic perspective view of a projection apparatus according to some other exemplary embodiments of the present disclosure, intended to show the external structure of the projection apparatus.

[0049] Figure 3 The diagram schematically illustrates the circulation paths of internal air within the accommodating space and external air outside the accommodating space of a projection device according to some exemplary embodiments of the present disclosure.

[0050] Figure 4 The focuser and baffle of a projection device according to some exemplary embodiments of the present disclosure are schematically shown.

[0051] Figure 5 This is an enlarged schematic diagram of the first air inlet of the first fan of the projection device according to some exemplary embodiments of the present disclosure, with emphasis on the various functional areas of the first air inlet.

[0052] Figure 6A and Figure 6B The schematic diagram illustrates the positional relationship of the display panel, first polarizing element, second polarizing element, light-transmitting portion, first lens, and second lens of a projection device according to some exemplary embodiments of the present disclosure along the light travel direction.

[0053] Figure 7 The optical path diagram of a projection device according to some exemplary embodiments of the present disclosure is shown schematically in a simplified manner.

[0054] Figure 8 An exploded view schematically illustrates how the display panel and the first or second lens are secured to the mounting frame via clips.

[0055] Figure 9 The diagram schematically illustrates, in a simplified manner, the fit between the display panel of a projection device according to some exemplary embodiments of the present disclosure and a groove on the inner surface of the housing.

[0056] Figure 10 The diagram schematically illustrates the circulation paths of internal air within the accommodating space of the projection apparatus according to some other exemplary embodiments of the present disclosure and the circulation paths of external air outside the accommodating space.

[0057] Figure 11 for Figure 10 A three-dimensional view of the second fan in the projection device.

[0058] Figure 12 for Figure 10 A three-dimensional view of the second fan from another angle in the projection device.

[0059] Figure 13 for Figure 10 A reference schematic diagram of a local location in the projection device shown.

[0060] Figure 14 This is a schematic diagram showing the positional relationship between the second reflector and the ventilation section provided in some exemplary embodiments of this disclosure.

[0061] Figure 15 This is a schematic diagram of the optical elements in the projection apparatus provided in some exemplary embodiments of this disclosure.

[0062] Figure 16 This is a schematic diagram of the optical path when the display surface of the display panel is parallel to the plane where the second lens is located.

[0063] Figure 17 This is a schematic diagram of the telecentric optical path of the projection device provided in some exemplary embodiments of this disclosure.

[0064] Figure 18 for Figure 15A schematic diagram of the display panel, second lens, first reflector, and projection lens in the projection device shown.

[0065] Figure 19 This is a schematic diagram illustrating the principle of off-axis projection with a rotation angle.

[0066] Figure 20A This is a schematic diagram showing the relationship between the projection device and the ground plane provided in some exemplary embodiments of this disclosure.

[0067] Figure 20B This is a schematic diagram showing the relationship between the projection device and the ground plane provided in some other exemplary embodiments of this disclosure.

[0068] Figure 21A This is a partial optical path diagram of a projection device according to some exemplary embodiments of the present disclosure.

[0069] Figure 21B This is a front view of the light-emitting element and its base of a projection device according to some exemplary embodiments of the present disclosure.

[0070] Figure 22A A three-view drawing of a condenser lens of a projection apparatus according to some exemplary embodiments of the present disclosure.

[0071] Figure 22B Another three-view diagram of a condenser lens of a projection device according to some exemplary embodiments of the present disclosure.

[0072] Figure 23 This is another outline view of the lens base of a projection device according to some exemplary embodiments of the present disclosure.

[0073] Figure 24A This is a simulation diagram of the imaging optical path of a projection device according to some exemplary embodiments of the present disclosure.

[0074] Figure 24B This is a simulation diagram of the illuminance of the display area of ​​the display panel of a projection device according to some exemplary embodiments of the present disclosure.

[0075] Figure 25 This is a schematic diagram of a second reflector in a projection device according to some exemplary embodiments of the present disclosure.

[0076] Figure 26 for Figure 25 The optical path diagram of the second reflector is shown.

[0077] Figure 27 This is a schematic diagram of a second reflector in a projection device according to some other exemplary embodiments of the present disclosure.

[0078] Figure 28 for Figure 27 The optical path diagram of the second reflector is shown.

[0079] Figure 29 This is a schematic diagram of a second reflector in a projection device according to some further exemplary embodiments of the present disclosure.

[0080] Figure 30 for Figure 28 The optical path diagram of the second reflector is shown.

[0081] Figure 31 This is a schematic diagram of a first reflector in a projection device according to some exemplary embodiments of the present disclosure. Detailed Implementation

[0082] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present disclosure and not intended to limit the scope of protection of the present disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the accompanying drawings.

[0083] It should be noted that, unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other. This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0084] It should be noted that the directional terms “up, down, front, back (back), horizontal, vertical” in this disclosure are relative concepts, not absolute concepts, unless otherwise stated. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0085] It should be noted that, in this disclosure, the numerical range expressed in the form [A, B] indicates a range from value A to value B, including both values ​​A and B. The numerical range expressed in the form (A, B) indicates a range from value A to value B, excluding both values ​​A and B. The numerical range expressed in the form [A, B) indicates a range from value A to value B, including value A but excluding value B. The numerical range expressed in the form (A, B] indicates a range from value A to value B, including value B but excluding value A. Furthermore, the numerical range expressed in the form "AB" or "A~B" indicates a range from value A to value B, including both values ​​A and B.

[0086] Unless otherwise defined, the term "rectangle" as used in this disclosure includes rectangles in the general sense as well as rounded rectangles, where the length of the longer side (i.e., length) and the length of the shorter side (i.e., width) of a rounded rectangle are the length of the longer side and the length of the shorter side after the rounded rectangle is converted back to a general rectangle, respectively.

[0087] Unless otherwise defined, the upper and lower bases of the trapezoid in this disclosure are defined by their length relationship, wherein the length of the upper base is less than the length of the lower base.

[0088] Regarding the optical elements in this disclosure, when describing the positional relationship, the meaning of element A being located on the side of element B closer to element C can be understood in one of the following ways, depending on the actual structure of the optical path: First, in the optical path, the main ray of light passes through element A first and then element B during its journey from element C to element B; Second, in the optical path, the main ray of light passes through element A first and then element C during its journey from element B to element C.

[0089] Regarding the optical elements in this disclosure, when describing the positional relationship, the meaning of element A being located on the side of element B that is farthest from element C can be understood in one of the following ways, depending on the actual structure of the optical path: First, in the optical path, the main ray of light passes through element B before passing through element A in the process of traveling from element C to element A; Second, in the optical path, the main ray of light passes through element B before passing through element C in the process of traveling from element A to element C.

[0090] For ease of description and brevity, this disclosure uses the usual working position of the projection device as a reference, that is, the side of the projection device facing the projected image (e.g., the projection screen) is referred to as the front side or front-facing side; the rear side or rearward side refers to the side of the projection device that is away from the projected image; the left and right sides are the sides perpendicular to the front-back direction. The top and bottom sides are the directions perpendicular to both the front-back and left-back directions.

[0091] Currently, the main projection devices on the market include CRT (Cathode Ray Tube) projectors, LCD (Liquid Crystal Display) projectors, and DLP (Digital Light Processing) projectors. LCD projectors mainly include single-LCD projectors and triple-LCD projectors. Single-LCD projectors have a simple structure and low cost, making them suitable for low- and middle-income consumers, and therefore have considerable growth potential.

[0092] Figure 1A , 1D Figures 1 and 1E show schematic perspective views of a projection apparatus according to some exemplary embodiments of the present disclosure in cross-section, intended to illustrate the internal structure of the projection apparatus. Figure 1B and Figure 1C This is a schematic perspective view of a first heat sink of a projection device according to some exemplary embodiments of the present disclosure. Figure 2 This is a schematic perspective view of a projection apparatus according to other exemplary embodiments of the present disclosure, intended to show the external structure of the projection apparatus. Figures 1A to 2As shown, the projection device includes: housing 1, light source assembly 2, projection lens 3, and first heat sink 4.

[0093] The light source assembly 2 includes a light-emitting element 21 and a condenser lens 23 located on the light-emitting side of the light-emitting element 21. The condenser lens 23 is configured to focus or shape the light emitted by the light-emitting element 21. The condenser lens 23 may be a plano-convex lens. In some embodiments, the light source assembly 2 further includes a light-emitting element base 22, on which the light-emitting element 21 is located.

[0094] The housing 1 includes a front surface and a rear surface opposite to each other. The front surface includes a first opening P1 and a second opening P2. The housing 1 also includes a third opening P3, at least a portion of which is located on the rear surface. A light-emitting element 21 is located at the first opening P1; a projection lens 3 is located at the second opening P2; and a first heat sink 4 is located at the third opening P3 of the housing 1. The light-emitting element 21, the projection lens 3, the first heat sink 4, and the housing 1 together constitute the receiving space SP.

[0095] In the projection device disclosed herein, the heat dissipation efficiency of the projection device is significantly improved by providing a first heat sink 4 with a large heat dissipation area at the third opening P3 of the housing 1. On the other hand, the first heat sink 4 and the housing 1 together constitute the receiving space SP, and there are no large-area perforated exhaust holes on the housing 1, so there is no friction between the air and the housing 1 during exhaust, which significantly reduces the operating noise of the projection device.

[0096] Preferably, the housing space SP is a closed housing space, so as to prevent dust from entering the housing and keep the optical components clean.

[0097] In some embodiments, such as Figure 1A , Figure 1D and Figure 1E As shown, the projection device may further include a first fan 5, which is located on the side of the light-emitting component 2 away from the receiving space SP. In some embodiments, the first fan 5 is an axial flow fan, and the pumping direction of the first fan 5 is parallel to the axial direction of the first fan 5. The first fan 5 includes a first air inlet 51 disposed toward the light-emitting element base 22 and a first air outlet 52 opposite to the first air inlet 51.

[0098] The first fan 5 draws in air that has been heated by the first radiator 4, dissipating the heat and further improving heat dissipation efficiency. Furthermore, the first air inlet 51 is positioned opposite the light-emitting element base 22, simultaneously providing heat dissipation for the light-emitting element. Preferably, a first gap is provided between the first air inlet 51 and the light-emitting element base 22. This first gap facilitates sufficient heat exchange between the light-emitting element base 22 and the air, improving the heat dissipation efficiency of the light-emitting element base 22.

[0099] Figure 3 The diagram schematically illustrates the circulation path of internal air within the accommodating space of a projection device according to some exemplary embodiments of the present disclosure and the circulation path of external air outside the accommodating space. Figure 5 This is an enlarged schematic diagram of the first air inlet of the first fan of the projection device according to some exemplary embodiments of the present disclosure, emphasizing the various functional areas of the first air inlet. Please refer to... Figures 1A to 1D , Figure 3 and Figure 5 The first air inlet 51 includes a first region Z1 covered by the orthographic projection of the light-emitting element base 22 onto the first air inlet 51, and a second region Z2 located on the side of the first region Z1 away from the projection lens 3. The second region Z2 is located on the side of the first region Z1 away from the projection lens 3, which allows hot air passing through the first heat sink 4 to enter the first fan 5 without obstruction, thereby increasing the heat dissipation efficiency of the first fan.

[0100] Preferably, the first air inlet 51 also includes a third region Z3 located on the side of the first region Z1 away from the second region Z2, thus increasing the space for airflow and improving heat dissipation efficiency.

[0101] More preferably, the width W3 of the third region Z3 is smaller than the width W2 of the second region Z2. That is, the first region Z1 is set to be closer to the projection lens 3 within the overall height range of the first air inlet 51, which can increase the space for airflow below and improve heat dissipation efficiency.

[0102] In some embodiments, such as Figure 1A As shown, the projection device also includes a base plate 10, which is disposed opposite to the housing 1; a first external air duct CH1 is formed between the housing 1 and the base plate 10; the first external air duct CH1 is used to allow air to enter the first fan 5 after passing through the first external air duct CH1 when the projection device is working. Preferably, the first external air duct CH1 is disposed opposite to the second region Z2.

[0103] Optionally, the base plate 10 is disposed opposite to a portion of the first radiator 4, and a portion of the first radiator 4 and the base plate 10 constitute a first external air duct CH1. (See reference) Figure 1AThe first radiator 4 includes a first radiator first portion 41, which is disposed opposite to the base plate 10. It is understood that the first radiator first portion 41 being disposed opposite to the base plate 10 includes the first radiator first portion 41 being parallel to the base plate 10, and also includes the acute angle formed between the first radiator first portion 41 and the base plate 10 being less than 45°. In this way, the heat dissipated by the first radiator 4 can more effectively enter the first external air duct CH1, improving heat dissipation efficiency. Preferably, the acute angle between the first radiator first portion 41 and the base plate 10 is less than or equal to 20°; for example, the acute angle between the first radiator first portion 41 and the base plate 10 can be in the range of [5°, 15°]; for example, the acute angle between the first radiator first portion 41 and the base plate 10 can be in the range of [8°, 12°]; for example, it can be 10°. It should be noted that when the first part 41 of the first heat sink includes a wrapping portion that encloses the receiving space SP and heat dissipation fins located on the side of the wrapping portion away from the receiving space SP, the acute angle between the first part 41 of the first heat sink and the base plate 10 can be understood as the acute angle between the wrapping portion of the first part 41 of the first heat sink and the base plate 10.

[0104] Specifically, the idea that a portion of the first radiator 4 and the base plate 10 constitute the first external air duct CH1 can be understood as the base plate 10 and the first radiator 4 having a gap, which constitutes at least a portion of the first external air duct CH1. In some embodiments, the first radiator 4 and the base plate 10 may also be in direct contact, and the first radiator 4 includes a path that allows airflow, thus the ventilation channel formed by the first radiator 4 and the base plate 10 is at least a portion of the first external air duct.

[0105] In some embodiments, the base plate 10 includes a base plate support surface 101 and a base plate support foot 102, the base plate support foot 102 being closer to the surface on which the projection device is placed (e.g., in direct contact with the surface on which the projection device is placed) than the base plate support surface 101; the base plate 10 may also include a base plate bearing structure 103 for supporting the housing 1.

[0106] In some embodiments, such as Figure 1D and Figure 3 As shown, the projection device may further include a circuit board 8, which is disposed opposite to the housing 1, and the housing 1 and the circuit board 8 form a second external air duct CH2; the second external air duct CH2 is used to allow air to enter the first fan 5 after passing through the second external air duct CH2 when the projection device is working; the second external air duct CH2 is disposed opposite to the second region Z2.

[0107] For example, circuit board 8 can be a system board. Circuit board 8 can be configured to drive at least one of the following: display panel, light-emitting element, fan, and focusing assembly.

[0108] Optionally, the circuit board 8 is disposed opposite to a portion of the first heat sink 4, and a portion of the first heat sink 4 and the circuit board 8 constitute a first external air duct CH1. (See reference) Figure 1B and 1C The first heat sink 4 includes a first heat sink first portion 41, which is disposed opposite to the circuit board 8. It is understood that the first heat sink first portion 41 being disposed opposite to the circuit board 8 includes the first heat sink first portion 41 and the circuit board 8 having parallel extension surfaces, and also includes the acute angle formed by the extension surfaces of the first heat sink first portion 41 and the circuit board 8 being less than 45°. In this way, the heat dissipated by the first heat sink 4 can more effectively enter the first external air duct CH1, improving heat dissipation efficiency. Preferably, the acute angle between the first heat sink first portion 41 and the base plate 10 is less than or equal to 20°. For example, the acute angle between the first heat sink first portion 41 and the base plate 10 can be in the range of [5°, 15°]; for example, the acute angle between the first heat sink first portion 41 and the base plate 10 can be in the range of [5°, 10°]; for example, it can be 10°. It should be noted that when the first part 41 of the first heat sink includes a wrapping portion that encloses the receiving space SP and heat dissipation fins located on the side of the wrapping portion away from the receiving space SP, the acute angle between the first part 41 of the first heat sink and the base plate 10 can be understood as the acute angle between the wrapping portion of the first part 41 of the first heat sink and the base plate 10.

[0109] Specifically, the idea that a portion of the first heat sink 4 and the circuit board 8 constitute the second external air duct CH2 can be understood as the circuit board 8 and the first heat sink 4 having a gap, which constitutes at least a portion of the second external air duct CH2. In some embodiments, the first heat sink 4 and the circuit board 8 may also be in direct contact, with the first heat sink 4 including a path that allows airflow. Thus, the ventilation channel formed by the first heat sink 4 and the circuit board 8 constitutes at least a portion of the second external air duct CH2.

[0110] In some embodiments, the projection device further includes a support frame, which, during normal use, is closer to the surface on which the projection device is placed relative to the housing 1, and is used to support the housing 1. For example, the support frame includes a support surface 61 and support feet 62, wherein, during normal use, the support feet 62 are closer to the surface on which the projection device is placed relative to the support surface 61 (e.g., in direct contact with the surface on which the projection device is placed), and are used to support the support surface 61; the support surface 61 is used to support the housing 1. In some embodiments, the circuit board 8 is located on the side of the support surface 61 away from the housing 1; preferably, the support surface 61 includes a through hollow portion, so that the heat of the circuit board 8 can be carried away in time through the second external air duct CH2, avoiding heat accumulation.

[0111] Please see Figure 1D and Figure 3The first heat sink 4 can be bow-shaped overall. In this way, the first heat sink 4 can fully cover the main heat dissipation area inside the projection device from the rear side, which can facilitate heat exchange and improve heat dissipation efficiency.

[0112] In some embodiments, see Figures 1A to 1E ,as well as Figure 3 The first heat sink 4 includes a wrap-around portion 44 and a plurality of first heat dissipation fins 46 located on the side of the wrap-around portion 44 away from the receiving space SP. The wrap-around portion 44 covers a third opening P3. Each of the plurality of first heat dissipation fins 46 includes a first heat dissipation section. The first heat sink 4 is configured such that air passes between the plurality of first heat dissipation sections and then enters the first fan 5 through a first air inlet 51. For example, the number of first heat dissipation fins can be 15-25, the protrusion height can be 10-20 mm, and the width can be 20-38 mm.

[0113] For example, the first radiator 4 is a cast aluminum radiator.

[0114] Alternatively, the projection device may include at least one of a circuit board 8 and a base plate 6. In some embodiments, when the projection device includes a circuit board 8, at least a portion of the first heat dissipation portion is located between the enclosure portion 44 and the circuit board 8. In some embodiments, when the projection device includes a base plate 6, at least a portion of the first heat dissipation portion is located between the enclosure portion 44 and the base plate 6. This effectively achieves heat dissipation for the first heat dissipation fins 46. In practical applications, the first heat dissipation portion is preferably configured to be arranged along the airflow direction so as not to obstruct airflow. Preferably, the first heat dissipation portion is streamlined so as not to obstruct airflow. For example, when the first heat dissipation portion extends to a bend, it may be curved.

[0115] The wrapping part 44 includes a first sub-wrapping part located on the side where the rear surface of the housing 1 is located (e.g. Figure 1D As shown, it covers a third opening on the side where the rear surface is located (e.g., an arched shape) and a second sub-enclosing portion located on a side different from the side where the rear surface of housing 1 is located (e.g., Figure 1DAs shown, the second sub-wrapping part is located below the first sub-wrapping part and extends in a different direction than the first sub-wrapping part; the second sub-wrapping part and the first sub-wrapping part together cover the third opening. The second sub-wrapping part and the first sub-wrapping part are continuously arranged. The transition between the first sub-wrapping part and the second sub-wrapping part is in the form of a corner, or the radius of the arc at the transition between the first sub-wrapping part and the second sub-wrapping part is smaller than the radius of the arc at the transition between the first heat dissipation part corresponding to the first sub-wrapping part and the first heat dissipation part corresponding to the second sub-wrapping part. The angle (e.g., the corner) between the portion of the first sub-wrapping part near the second sub-wrapping part and the portion of the second sub-wrapping part near the first sub-wrapping part is greater than 90° and less than 150°, thus ensuring the heat dissipation area while taking into account the size of the machine. For example, the angle between the portion of the first sub-wrapping part near the second sub-wrapping part and the portion of the second sub-wrapping part near the first sub-wrapping part is greater than 90° and less than 150°.

[0116] For example, the first part 41 of the first radiator includes a second sub-enclosure and a first heat dissipation part corresponding to the second sub-enclosure.

[0117] The circuit board 8 includes a second heat dissipation section 81, which is located on the side of the circuit board 8 near the housing 1. Air passing through the first fan 5 can first pass through the second heat dissipation section 81, thereby further improving heat dissipation efficiency. The second heat dissipation section 81 may include a third heat dissipation fin; preferably, the third heat dissipation fin extends along the airflow direction.

[0118] In some embodiments, such as Figure 1D As shown, in the operating state of the projection device, the projection lens 3 is higher than the light source assembly 2; the housing 1 also includes a bottom surface and a top surface, the bottom surface being lower than the top surface, and the front surface and rear surface respectively connecting the top surface and the bottom surface. In the operating state of the projection device, the projection device is configured to form a first external air duct CH1 between the bottom surface and the placement surface GD of the projection device. The air entering the first air inlet 51 includes air that has passed through the first external air duct CH1, and the air entering the air duct carries heat dissipated from the first heat sink 4. In some embodiments, the projection device further includes a support structure 11 for supporting the housing 1.

[0119] Figure 6A and Figure 6B The diagram schematically illustrates the positional relationship of the display panel, first polarizing element, second polarizing element, light-transmitting portion, first lens, and second lens of a projection device according to some exemplary embodiments of the present disclosure along the light travel direction; Figure 7 The optical path diagram of a projection apparatus according to some exemplary embodiments of the present disclosure is shown schematically in a simplified manner. Please refer to it in conjunction with... Figures 6A to 7The projection device further includes: a first polarizing element POL1, a second polarizing element POL2, a display panel PNL, a first lens LNS1, and a second lens LNS2.

[0120] The first polarizing element POL1 is disposed on the light-emitting side of the light source assembly 2 and is used to convert the light emitted by the light source assembly 2 into first polarized light with a first polarization direction.

[0121] The display panel PNL is positioned on the side of the first polarizing element POL1 away from the light source assembly 2, and is used to adjust the polarization direction of the first polarized light to emit second polarized light. The polarization direction of the second polarized light is between the first polarization direction and the second polarization direction, and the first polarization direction is perpendicular to the second polarization direction. It should be noted that the polarization direction of the second polarized light being between the first polarization direction and the second polarization direction includes both cases where the polarization direction of the second polarized light is the same as the first polarization direction and cases where the polarization direction of the second polarized light is the same as the second polarization direction.

[0122] The first lens LNS1 is disposed on the side of the display panel PNL away from the light source assembly 2. Alternatively, the first lens LNS1 may also be disposed between the display panel PNL and the first polarizing element POL1.

[0123] The second polarizing element POL2 is disposed on the side of the display panel PNL away from the first polarizing element POL1, and is used to emit one of the polarized light in the first polarization direction and the polarized light in the second polarization direction from the projection lens. In some exemplary embodiments, the second polarizing element POL2 is a polarizing film material, which is attached to the light-emitting surface of the display panel PNL.

[0124] In some exemplary embodiments, the first polarizing element POL1 is a polarizing film material, which is bonded to the light-incident surface of the display panel PNL. In other exemplary embodiments, there is a gap between the first polarizing element POL1 and the display panel PNL, so that the heat generated by the first polarizing element POL1 during light filtering is difficult to be conducted to the display panel PNL, thus avoiding the display effect being affected by the excessive temperature of the liquid crystal display panel.

[0125] In some embodiments, the projection device further includes a light-transmitting portion (GLS). For example, the first polarizing element (POL) is a polarizing film material and is bonded to the light-transmitting portion (GLS). A gap exists between the light-transmitting portion (GLS) and the display panel (PNL), thus preventing the heat generated by the first polarizing element (POL) during light filtering from affecting the operation of the display panel (PNL). The material of the light-transmitting portion (GLS) is, for example, glass; the material of the light-transmitting portion (GLS) can, for example, serve a heat-insulating function.

[0126] In some embodiments, the two sides of the light-transmitting part GLS are flat, and light does not converge or diverge before and after passing through the light-transmitting part GLS; it is understood that the light-transmitting part GLS does not act as an optical lens.

[0127] In some embodiments, the first polarizing element POL1 is attached to the side of the light-transmitting portion GLS away from the display panel PNL. In this way, the light-transmitting portion GLS can be used to block or reduce the heat generated by the first polarizing element POL1 receiving light from the display panel PNL, thereby avoiding any impact on the display effect.

[0128] In some embodiments, the first polarizing element POL1 may also be attached to the side of the light-transmitting portion GLS near the display panel PNL.

[0129] In some embodiments, the display panel PNL includes an array substrate and a color filter substrate, wherein the second polarizing element POL2 is located on the side of the array substrate away from the color filter substrate. For example, the second polarizing element POL2 is bonded to the array substrate. For example, the second polarizing element POL2 is located on the light-emitting side of the display panel, so that the projected light transmitted through the display panel PNL first passes through the color filter substrate and then through the array substrate before being emitted. In this way, the heat accumulated on the surface of the color filter substrate can be reduced, the surface temperature of the display panel can be lowered, and the display panel can be protected.

[0130] In some embodiments, such as Figure 6A As shown, the first lens LNS1 is disposed on the side of the display panel PNL away from the light source assembly 2, and the light-transmitting portion GLS is located between the light source assembly 2 and the display panel PNL, with a second gap d2 between the light-transmitting portion GLS and the display panel PNL. In other embodiments, such as Figure 6B As shown, the first lens LNS1 is disposed between the display panel PNL and the first polarizing element POL1, the light-transmitting part GLS is located between the light source assembly 2 and the first lens LNS1, and there is a second gap d2 between the light-transmitting part GLS and the first lens LNS1.

[0131] In some exemplary embodiments, such as Figure 6A and Figure 6B As shown, the second gap d2 can be a gap located on the light-emitting side of the light-transmitting section GLS and adjacent to the light-transmitting section GLS; in some other exemplary embodiments, the first polarizing element POL1 is attached to the light-emitting side of the light-transmitting section GLS, and the second gap d2 is a gap located on the light-emitting side of the first polarizing element POL1 and adjacent to the first polarizing element POL1. It should be noted that "adjacent" can be understood as meaning that there are no other elements between them.

[0132] Specifically, the first lens LNS1 is a convex lens. In some embodiments, the first lens LNS1 can be a Fresnel lens or an aspherical mirror, preferably a Fresnel lens.

[0133] In some embodiments, the display device further includes a first reflector MR1, which is configured to reflect light emitted from the display panel PNL into the projection lens 3. Specifically, the first reflector MR1 is disposed on the side of the display panel PNL away from the light source assembly 2, and the first lens LNS1 is disposed on the side of the first lens LNS1 away from the light source assembly 2. The second reflector MR2 may be a plane reflector.

[0134] It should be noted that when it is said that the first element is located on the side of the second element that is far away from the light source assembly 2, it can be understood that in terms of spatial position, the first element is farther away from the light source assembly 2 than the second element, or it can be understood that in the optical path, the main light rays pass through the second element first and then through the first element.

[0135] In some exemplary embodiments, the second polarizing element POL2 may be the same element as the first reflector MR1 or a different element. Specifically, when the second polarizing element POL2 is the same element as the first reflector MR1, the first reflector MR1 may be configured to emit one of the polarized light in the first polarization direction and the polarized light in the second polarization direction from the projection lens 3. In this way, the light-emitting surface of the display panel PNL does not need to be attached to the second polarizing element POL2, reducing heat accumulation in local areas, and the projector can set a higher projection brightness image.

[0136] In some embodiments, when the second polarizing element POL2 and the first reflector MR1 are the same element, the first reflector MR1 may include: a multilayer optical film layer integrated together. The multilayer optical film layer may be disposed on the side of the substrate (such as a glass substrate) facing the display panel PLN and tilted towards the display panel PLN. Any two adjacent optical film layers have different refractive indices, thereby forming an optical interface; each optical interface corresponds to a wavelength band, and different optical interfaces correspond to different wavelength bands. Each optical interface is used to transmit polarized light with a wavelength within the corresponding wavelength band and a polarization direction of the first polarization direction, and to reflect polarized light with a wavelength within the corresponding wavelength band and a polarization direction of the second polarization direction. The number of optical film layers 42 may be 3, 4, 5, etc. For example, the multilayer optical film 42 has three optical interfaces. The first optical interface is used to transmit light in the red light band with the first polarization direction and to reflect light in the red light band with the second polarization direction. The second optical interface is used to transmit light in the green light band with the first polarization direction and to reflect light in the green light band with the second polarization direction. The third optical interface is used to transmit light in the blue light band with the first polarization direction and to reflect light in the blue light band with the second polarization direction.

[0137] Through the interfaces between the multiple optical film layers, polarized light with a first polarization direction in natural light can be transmitted, while polarized light with a second polarization direction in natural light can be reflected. Alternatively, the refractive index of each optical film layer can be adjusted so that each optical interface in the reflective component 40 can transmit polarized light with a wavelength within the corresponding band and a polarization direction of the second polarization direction, and reflect polarized light with a wavelength within the corresponding band and a polarization direction of the first polarization direction.

[0138] Please refer to the following: Figure 1D and Figure 3 The projection device further includes a second fan 7 located within the accommodating space SP, used to circulate the internal air within the accommodating space SP. The internal hot air exchanges heat with the external cold air through a first radiator 4. In some exemplary embodiments, the second fan 7 is a centrifugal fan, which includes a second air inlet 71 and a second air outlet 72. The second air outlet 72 discharges internal air, and the second air inlet 71 draws in internal air, causing the internal air to circulate in at least a portion of the accommodating space SP.

[0139] In some embodiments, the second air inlet 71 is disposed opposite to the first radiator 4, so that the internal air cooled by the first radiator 4 directly enters the second air inlet 71 for the next air flow cycle, which can achieve effective cooling inside the containment space SP.

[0140] In some embodiments, the flow path of the internal air includes the second gap d2, that is, the internal air is driven by the second fan 7 to flow through the second gap d2 to remove heat from the vicinity of the second gap d2.

[0141] In some embodiments, reference Figure 6A and Figure 6B A third gap d3 exists between the first lens LNS1 and the display panel PNL. The flow path of the internal air includes the third gap d3. The third gap d3 and the second gap d2 are arranged side by side. The flow direction of the internal air in the second gap d2 is the same as or opposite to the flow direction of the internal air in the third gap d3. In some exemplary embodiments, reference is made to... Figure 6A The second gap d2 and the third gap d3 are located on the light-incident surface and the light-emitting surface of the display panel PNL, respectively, and the airflow direction inside the light-incident surface is opposite to the airflow direction inside the light-emitting surface. Specifically, the side-by-side arrangement of the third gap d3 and the second gap d2 can be understood as the third gap d3 and the second gap d2 having the same or approximately the same extension direction, for example, the angle between the extension directions of the third gap d3 and the second gap d2 is within 30°.

[0142] In some exemplary embodiments, the internal air circulates internally by sequentially passing through a second air outlet 72, a second air duct including a second gap d2, a third air duct including a third gap d3, a first internal air duct CH', and a second air inlet 71. At least a portion of the first radiator 4 forms one sidewall of the first internal air duct CH'. Specifically, as... Figure 3 As shown, the first radiator 4 includes a wrap-around portion, at least a portion of which forms one side wall of the first internal air duct CH'. Preferably, refer to... Figure 1B and 1C The first heat sink 4 also includes second heat dissipation fins extending into the first internal air duct CH', thereby increasing the heat exchange efficiency between the first heat sink 4 and the outside. For example, the number of second heat dissipation fins can be 15-25, the protrusion height can be in the range of [10mm, 20mm], and the width can be in the range of [20mm, 38mm]. The extension direction of the second heat dissipation fins is consistent with the extension direction of the first internal air duct CH'.

[0143] In some embodiments, such as Figure 3As shown, in at least a portion of the region extending along the airflow direction of the first inner air duct CH', the width of the first inner air duct CH' gradually widens, thereby increasing the area for heat exchange between the first inner air duct CH' and the outside air and improving heat dissipation efficiency. Preferably, the difference between the width of the widest point of the first inner air duct CH' and the width at the inlet position of the first inner air duct CH' is in the range of 10mm-20mm, wherein the inlet of the first inner air duct CH' is connected to the third air duct, and the width of the first inner air duct CH' represents the width of the first inner air duct CH' in the direction perpendicular to the plane where the second air inlet 71 is located. For example, the width of the widest point of the first inner air duct CH' is between 2 and 3 times the width at the inlet position of the first inner air duct CH'. For example, the width of the widest point of the first inner air duct CH' is between 2 and 3 times the width of the third gap d3. For example, the widest point of the first inner air duct CH' is positioned opposite to the second air inlet 71.

[0144] In some embodiments, the first internal air duct CH' is directly connected to the second air inlet 71. In this way, the internal air cooled by the first radiator 4 directly enters the second air inlet 71 for the next air flow cycle, which can achieve effective cooling inside the containment space SP.

[0145] In some embodiments, the display device includes a second reflector MR2, which is configured to reflect light emitted from the light source assembly 2 into the display panel PLN. The second reflector MR2 may be a planar reflector.

[0146] In some embodiments, the display device includes a second lens LNS2, which is located between the second reflector MR2 and the display panel PLN, and is used to collimate the light reflected by the second reflector MR2. Thus, the light source assembly 2 is a collimated light source assembly.

[0147] In some exemplary embodiments, the second lens LNS2 is located on the side of the light-transmitting component GLS away from the display panel PLN.

[0148] In some exemplary embodiments, the second lens LNS2 is located between the first lens LNS1 and the light source assembly 2.

[0149] Specifically, the second lens LNS2 is a convex lens. In some exemplary embodiments, the second lens LNS2 can be a Fresnel lens or an aspherical mirror, preferably a Fresnel lens.

[0150] In some embodiments, such as Figure 3 As shown, the second fan 7 is located on the side of the second reflector MR2 away from the light source assembly 2; there is a fourth gap d4 between the second fan 7 and the first heat sink 4, and the first inner air duct CH' includes the fourth gap d4.

[0151] Figure 8An exploded view schematically illustrates how the display panel and the first or second lens are secured to the mounting frame via clips. Figure 9 The diagram schematically illustrates, in a simplified manner, the fit between the display panel of a projection device according to some exemplary embodiments of the present disclosure and a groove on the inner surface of the housing. Please refer to the appendix for further details. Figure 8 and 9 The projection device further includes a fixing frame 9, with the display panel PNL and the first lens LNS1 respectively embedded on opposite sides of the fixing frame 9. A third gap d3 exists between the first lens LNS1 and the display panel PNL. The fixing frame 9 includes two oppositely arranged through sides 91, one of which faces the first heat sink 4. Preferably, each through side includes a cutout portion 911, the area of ​​which occupies more than 80% of the area of ​​the through side 91. Specifically, the fixing frame 9 includes two oppositely arranged positioning sides 92; the two positioning sides 92 are connected to the two through sides 91. Each positioning side 92 includes a positioning part for cooperating with the housing 1 to position the fixing frame 9. For example, the positioning part includes a protruding ridge 921, the protruding ridge 921 extending in the same direction as the display panel PNL. For example, the fixing frame 9 also includes a U-shaped buckle 93; the display panel PNL, the fixing frame 9, and the first lens LNS1 are all disposed between the two ends of the U-shaped buckle 93, and the buckle 93 clamps at least one positioning side 92 of the fixing frame 9, that is, the U-shaped buckle defines the display panel PNL and the first lens LNS1 in the thickness direction. The position where the U-shaped buckle 93 clamps the positioning side 92 of the fixing frame 9 includes a mating protrusion 931. Preferably, the mating protrusion 931 and the protrusion 921 of the positioning part are continuously arranged to form a continuously distributed linear slide rail. For example, as Figure 9 As shown, the inner surface 10' of the housing 1 includes a groove 101', and a protrusion 921 engages with the groove 101' to achieve positioning and sliding of the fixing frame 9. The protrusion 921 is configured to slide within the groove 101', thereby pulling the display panel PNL out of or into the housing 1. It should be noted that the groove 101' can be part of the housing 1 or a mechanical structure connected to the housing 1.

[0152] In some exemplary embodiments, the first heat sink 4 is detachable from the housing 1. The mounting frame 9 can be inserted into or removed from the projection device after the first heat sink 4 is removed from the housing 1, thus facilitating the maintenance of the projection device.

[0153] Figure 4 The focuser and baffle of a projection device according to some exemplary embodiments of the present disclosure are schematically shown, and can be seen in conjunction with the drawings. Figure 2 and Figure 4The projection device includes a focusing assembly for focusing the projection lens 3, which includes a sensing assembly 13 and a driving assembly. The sensing assembly 13 includes a distance sensor configured to measure the projection distance between the projection lens 3 and the projected image (e.g., a projection screen). For example, the distance sensor may be a TOF (Time of Flight) sensor. The driving assembly is configured to drive the projection lens 3 to adjust its focus based on the measured projection distance.

[0154] In some exemplary embodiments, the drive assembly includes a drive motor 11, an actuator 12, and a focuser 14 disposed on the projection lens; the drive motor 11 drives the actuator 12 to move, and the actuator 12 is coupled to the focuser 14 to focus the projection lens 3. For example, the shaft of the drive motor 11 may be fixedly connected to the actuator 12. In some exemplary embodiments, the actuator 12 includes a first gear, and the focuser 14 includes transmission teeth 141 disposed on the outer periphery of the projection lens 3, the first gear and the transmission teeth 141 being coupled to each other through meshing.

[0155] In some exemplary embodiments, the focusing assembly further includes a limiting component for controlling the focusing range of the projection lens. The limiting component includes an optical coupler and a baffle 16, the relative position of which is fixed with respect to the focuser 14. The optical coupler determines whether the baffle 16 blocks or does not block light and sends a signal to provide instructions to the drive motor 11.

[0156] In some exemplary embodiments, such as Figure 4 As shown, the focusing mechanism 14 is a focusing ring, and the baffle 16 and the transmission gear 141 are both fixed around the focusing ring. The optical coupler includes a light emitter and a light receiver, and the baffle 16 is configured to block the optical path between the light emitter and the light receiver.

[0157] In some exemplary embodiments, the optical coupler is configured such that when the optical path between the emitter and the receiver is blocked by the baffle 16, the optical coupler transmits a first control signal to the circuit board to control the motor 11 to rotate for autofocus; and when the optical path between the emitter and the receiver is not blocked by the baffle 16, the optical coupler transmits a second control signal to the control circuit board to brake the motor 11.

[0158] The transmission ratio between the first gear and the transmission gear 141 is 1:3.5-4.5; the ratio of the root circle diameter of the first gear to the root circle diameter of the transmission gear 141 is 1:5.0-6.0; and the ratio of the tip circle diameter of the first gear to the tip circle diameter of the transmission gear 141 is 1:3.2-4.2. Thus, while minimizing the overall size of the projection device, the first gear and transmission gear 141 can ensure high driving efficiency and smoothness while maintaining accurate focusing.

[0159] In some exemplary embodiments, circuit board 8 is electrically connected to display panel PNL to control display panel PNL.

[0160] In some exemplary embodiments, circuit board 8 is electrically connected to a drive assembly to control the drive assembly.

[0161] Optionally, the second reflector MR2 and the first reflector MR1 are detachably mounted on the housing 1 within the receiving space SP.

[0162] Optionally, an airtight sealing filler is provided between the second opening P2 and the projection lens 3 to improve the airtightness of the containing space SP.

[0163] Optionally, an airtight sealing filler is provided between the first opening P1 and the plano lens 23 to improve the airtightness of the accommodating space SP.

[0164] Optionally, the part where the first radiator 4 engages with the third opening P3 of the housing 1 is provided with an airtight sealing filler to improve the airtightness of the accommodating space SP.

[0165] Optionally, the aforementioned airtight sealing packing is selected from at least one of silicone packing or rubber packing.

[0166] Optionally, see Figure 3 The projection device is configured such that, within the airtight containment space SP, driven by the second fan 7, the internal airflow sequentially flows through: the second air outlet 72, the second gap d2, the third gap d3, the fourth gap d4, and the second air inlet 71 of the second fan 7 for thermal circulation.

[0167] Optionally, a narrow, elongated hole is formed on at least one of the left and right sides of the housing 1 at a position corresponding to the light-transmitting part GLS. The width of the hole is greater than or equal to the thickness of the light-transmitting part GLS, so that the light-transmitting part GLS can be pulled out or put into the receiving space SP directly through the hole, which facilitates the replacement and maintenance of the light-transmitting part GLS.

[0168] Optionally, see Figure 1DThe projection device further includes a second heat sink HS located outside the housing 1 and in front of the light-emitting component 2. The second heat sink HS is thermally coupled to the light-emitting element base 22 of the light source component 2 via at least one heat pipe Cu to promote heat dissipation near the light source component 2. The second heat sink HS is larger than the light-emitting element base 22 and spaced apart from it by a certain distance to accommodate the first fan 5; in other words, the first fan 5 is positioned between the light-emitting element base 22 and the second heat sink HS. The materials of at least one heat pipe Cu and the light-emitting element base 22 include copper. In some exemplary embodiments, the second heat sink HS includes heat dissipation fins formed by stacking multiple aluminum sheets, and one end of each heat pipe Cu is connected to the light-emitting element base 22, while the other end is inserted into the second heat sink HS from its side. The connection between the heat pipe Cu and the light-emitting element base 22 is, for example, a welding connection.

[0169] Optionally, see Figure 2 The projection device also includes wind deflectors 15 disposed on the left and right sides of the projector, which facilitates the first fan 5 in drawing hot air from the vicinity of the first radiator 4. Specifically, the wind deflectors 15 are disposed on at least both sides of the first external air duct CH1.

[0170] Optionally, see Figure 3 The projection device is configured such that, outside the airtight containment space SP, driven by the first fan 5, external air flows sequentially through: multiple first heat dissipation fins of the first radiator 4, the first external air duct CH1 formed between the housing 1 and the base plate 6 (or the second external air duct CH2 formed between the housing 1 and the circuit board 8, or the third external air duct CH3 formed between the housing 1 and the placement surface GD), the first air inlet 51 of the first fan 5, and the first air outlet 52 of the first fan 5, so as to dissipate heat to the external environment.

[0171] In addition to the technical effects described in the first few paragraphs of the Detailed Embodiments section, the projection device according to this disclosure also has the following beneficial effects.

[0172] On the one hand, most common single-LCD projectors on the market currently lack autofocus functionality. When using such a projector without autofocus, manual focusing is required beforehand based on the distance between the projection lens and the projection screen. When the projection screen or projector moves, the distance between the projection lens and the projection screen changes, necessitating manual refocusing. This manual focusing method is cumbersome and yields poor focusing results. In contrast, the projector provided in this disclosure includes a distance sensor and a driving component capable of measuring the projection distance between the projection lens and the projection screen, and the driving component can drive a focuser for automatic focusing based on the projection distance. Compared to traditional projectors requiring manual focusing, the projector of this disclosure is simpler to operate, more accurate in focusing, and more efficient.

[0173] On the other hand, by simply setting a second reflector MR2 in the light-emitting side of the light source assembly 2 to replace the traditional light collimation system containing multiple complex optical elements, the light path can be folded more effectively (that is, the path of light travel is shortened), and the size of the projection device can be further reduced while ensuring the direction of light travel, thus improving the portability of the projection device.

[0174] On the other hand, considering that the display module PNL and the first lens LNS1 are prone to malfunctions during use, and that it is very laborious to replace these two components each time in conventional products, this disclosure provides an integrated and compact display unit by clamping the first lens LNS1 and the display panel PNL together with a fixing frame and a U-shaped buckle. The unit has good overall sealing, stable structure, and is easy to disassemble and repair.

[0175] Figure 10 The illustration schematically shows the circulation path of internal air within the housing space of a projection device according to some other exemplary embodiments of the present disclosure and the circulation path of external air outside the housing space. Figure 3 The projection devices shown are the same as those shown. Figure 10 The projection device shown also includes: a housing 1, a light source assembly 2, and a projection lens 3. The projection lens 3 has an internal receiving space, within which a second reflector MR2, a second fan 7, and a lens assembly LNSG are disposed. The second reflector MR2 is located on the light-emitting side of the light source assembly 2 and is used to reflect the light emitted by the light source assembly 2 into the lens assembly LNSG. The lens assembly LNSG is used to collimate the light. For example, the lens assembly LNSG may include: the aforementioned light-transmitting portion GLS and the second lens LNS2.

[0176] exist Figure 10 In the projection device shown, the accommodating space includes an airflow space where air can flow. Specifically, the airflow space may include a first subspace SP1 and a second subspace SP2, wherein the first subspace SP1 is defined by the light source assembly 2, the second reflector MR2, the lens assembly LNSG, and a portion of the housing 1, and the second subspace SP2 is located around the first subspace SP1. It should be noted that the second subspace SP2 being located around the first subspace SP1 does not necessarily mean that the second subspace SP2 is a continuous annular structure surrounding the first subspace SP1; it could also mean that the second subspace SP2 is located on one side of the first subspace SP1; or, a portion of the second subspace SP2 is located on one side of the first subspace SP1, and another portion is located on the other side of the first subspace SP1.

[0177] The second fan 7 is used to drive the internal air circulation within the air flow space, so that the internal air circulates between the first subspace SP1 and the second subspace SP2.

[0178] In the projection device, the first subspace SP1 will accumulate a certain amount of heat due to the emission of light from the light source component 2, and Figure 10 The second fan 7 in the middle can drive the internal air to circulate between the first subspace SP1 and the second subspace SP2, which is beneficial for heat dissipation of the first subspace SP1 and improves the reliability of the projection device. Furthermore, by driving the airflow in the airflow space through the second fan 7, the temperature in the airflow space is kept balanced, which is beneficial for the overall heat dissipation of the projection device and the operation of the components.

[0179] Among them, the second fan 7 can be a centrifugal fan. Figure 11 for Figure 10 A three-dimensional view of the second fan in the projection device. Figure 12 for Figure 10 A three-dimensional view of the second fan from another angle in the projection device. (See image below.) Figure 11 and Figure 12 As shown, the second fan 7 includes a fan housing 1 and a centrifugal fan located within the fan housing 1. The fan housing 1 includes a functional area and a non-functional area, wherein the functional area includes a region overlapping the centrifugal fan axially and a region where the air output channel is located. The functional area is provided with a second air inlet 71 and a second air outlet 72, and the non-functional area is provided with a ventilation section 73 penetrating the fan housing 1.

[0180] Please refer to this as well. Figures 10 to 12 The second air inlet 71 faces the second subspace SP2, and the second air outlet 72 is used to simultaneously discharge air into the first subspace SP1 and the second subspace SP2. Air discharged into the first subspace SP1 via the second air outlet 72 passes through the ventilation section 73, enters the second subspace SP2, and then enters the second air inlet 71; air discharged into the second subspace SP2 via the second air outlet 72 flows within the second subspace SP2 before entering the second air inlet 71. This allows for air circulation within the airflow space.

[0181] In some embodiments, such as Figure 10As shown, the second subspace SP2 includes a first internal air duct CH' located between the first radiator 4 and the second fan 7, with at least a portion of the first radiator 4 forming one sidewall of the first internal air duct CH'. The second air inlet 71 is positioned facing the first internal air duct CH'. Air discharged into the first subspace SP1 through the second air outlet 72 passes sequentially through the ventilation section 73 and the first internal air duct CH' before entering the second air inlet 71, allowing the air carrying heat from the first subspace SP1 to exchange heat with the first radiator 4, which then dissipates the heat to the external environment.

[0182] exist Figure 10 In the projection device shown, the positional relationship of the optical elements along the light propagation direction can be found in [reference needed]. Figure 6A and Figure 6B ,like Figure 6A and Figure 6B A PNL and a first lens LNS1 are disposed on the side of the lens assembly LNSG away from the second reflector MR2. A second gap d2 is provided between the lens assembly LNSG and the PNL, and a third gap d3 is provided between the first lens LNS1 and the PNL. The second gap d2 is closer to the first subspace SP1 than the third gap d3. In some embodiments, such as... Figure 6A As shown, the display panel PNL is located on the side of the lens assembly LNSG away from the second reflector MR2, and the first lens LNS1 is located on the side of the display panel PNL away from the lens assembly LNSG. Of course, in other embodiments, such as... Figure 6B As shown, the first lens LNS1 can also be located on the side of the lens assembly LNSG away from the second reflector MR2, while the display panel PNL is located on the side of the first lens LNS1 away from the lens assembly LNSG.

[0183] The second subspace SP2 also includes a U-shaped air duct, which comprises a second air duct and a third air duct arranged side by side and interconnected. The second air duct includes a second gap d2, and the third air duct includes a third gap d3. The airflow path of the second air outlet 72 into the second subspace SP2 includes the second air duct, the third air duct, and the first inner air duct CH'. That is, the internal air can flow through the second air duct, the third air duct, and the first inner air duct CH', thereby enabling sufficient heat dissipation for the display panel PNL.

[0184] like Figure 10As shown, the U-shaped air duct also includes a fourth air duct CH4, which is connected to the second and third air ducts. A portion of the second air outlet 72 faces the second air duct. Air discharged from the second air outlet 72 into the second subspace SP2 passes sequentially through the second air duct, the fourth air duct, the third air duct, and the first inner air duct CH' before entering the second air inlet 71. The housing 1 also includes a curved portion 1a corresponding to the fourth air duct CH4. The inner wall of the curved portion 1a is an arc surface, which protrudes away from the second and third air ducts, so that the airflow from the second air duct can enter the third channel along the arc surface.

[0185] In the following embodiments, the second air outlet 72 is divided into a first region and a second region. The second region is the area of ​​the second air outlet 72 opposite to the second subspace SP2; the first region is the remaining area of ​​the second air outlet 72 located on the side of the second region closer to the first subspace SP1. The area of ​​the first region is defined as the first effective discharge area S1, and the area of ​​the second region is defined as the second effective discharge area S2. In some embodiments, there are no remaining areas on the side of the second region away from the first subspace SP1, and the air discharged from the second air outlet 72 at a position away from the second region is not blocked by the second reflector MR2. In this case, the first region is the area of ​​the second air outlet 72 other than the second region.

[0186] For example, in the lens assembly LNSG, the side closest to both the display panel PNL and the second air outlet is defined as the first side edge, and the reference line at the second air outlet 72 that is parallel to the first side edge and closest to the first side edge serves as the boundary line between the first region and the second region.

[0187] For example, the area in the second air outlet 72 corresponding to the first side edge and the display panel PNL is designated as the second area.

[0188] It should be noted that when the lens assembly LNSG includes a light-transmitting portion GLS and a second lens LNS2, and no other structure is provided between the light-transmitting portion GLS and the second air outlet 72 (i.e., no other structure will block the airflow from the second air outlet 72), then among the side edges of the surface of the light-transmitting portion GLS near the display panel PNL, the side edge closer to the second air outlet 72 is designated as the aforementioned first side edge. In some embodiments, in addition to including the light-transmitting portion GLS and the second lens LNS2, the lens assembly LNSG also includes a fixing member FS. The fixing member FS includes a first fixing member FS1 for limiting the light-transmitting portion GLS. The first fixing member FS1 is opposite to the second air outlet 72. In this case, the side edge of the first fixing member FS1 closer to the display panel PNL and the second air outlet 72 is designated as the aforementioned first side edge.

[0189] For example, the lens assembly LNSG has multiple side edges on the side near the second reflector MR2, and the side edge near the second air outlet 72 is defined as the second side edge. In some embodiments, the distance between the edge of the second reflector MR2 near the second air outlet 72 and the aforementioned second side edge in the extending direction perpendicular to the entire lens assembly LNSG is greater than or equal to half the height of the aforementioned first region.

[0190] For example, the distance between the first side edge and the extended surface of the display panel PNL near the first side edge is greater than or equal to the height of the second region mentioned above, so that the air discharged from the second air outlet 72 can smoothly enter the first subspace SP1 and the second subspace SP2.

[0191] In this design, both the first and second regions of the second air outlet 72 are strip-shaped. The width of the first and second regions is defined as the length of their respective strips, and the height of the first and second regions is defined as the width of their respective strips. It can be understood that the length of the strip is greater than its width.

[0192] like Figure 6A and Figure 6B As shown, a second polarizing element POL2 is disposed on the side of the display panel PNL away from the second gap d2. During the display process of the display panel PNL, the second polarizing element POL2 can transmit either polarized light in the first polarization direction or polarized light in the second polarization direction, while absorbing the other. Therefore, the second subspace SP2 generates more heat than the first subspace SP1. In order to maintain the heat balance between the first subspace SP1 and the second subspace SP2, in some embodiments, the second effective exhaust area S2 is set to be larger than the ventilation area of ​​the first effective exhaust area S1. For example, the second effective exhaust area S2 is (1, 3] times the first effective exhaust area S1, thereby further maintaining the heat balance between the first subspace SP1 and the second subspace SP2.

[0193] In some embodiments, reference Figure 13The lens assembly LNSG is configured to divert the air discharged from the second air outlet 72, causing a portion of the air AF1 discharged from the second air outlet 72 to enter the first subspace SP1, and a portion of the air AF2 discharged from the second air outlet 72 to enter the second subspace SP2. The aforementioned "second effective discharge area S2 is (1, 3] times the first effective discharge area S1" means that, per unit time, the volume of air AF2 discharged from the second air outlet 72 into the second subspace SP2 is greater than the volume of air AF1 discharged from the second air outlet 72 into the first subspace SP1. Furthermore, it achieves an effect close to, per unit time, that the volume of air AF2 discharged from the second air outlet 72 into the second subspace SP2 is (1, 3] times the volume of air AF1 discharged from the second air outlet 72 into the first subspace SP1. Preferably, the second effective discharge area S2 is twice the first effective discharge area S1, thereby maximizing the maintenance of heat balance within the first subspace SP1 and the second subspace SP2.

[0194] It is understandable that when the lens assembly LNSG includes a light-transmitting portion GLS and a second lens LNS2, there may be a gap between the light-transmitting portion GLS and the second lens LNS2. For example, the end of this gap away from the second air outlet 72 is blocked by a structural component, so that no airflow may form in the gap between the light-transmitting portion GLS and the second lens LNS2.

[0195] In some embodiments, please combine Figure 10 and Figure 13 The second air outlet 72 includes a first opening 721 and a second opening 722, which are arranged side by side. At least a portion of the first opening 721 is configured to discharge air toward the first subspace SP1, and at least a portion of the second opening 722 is configured to discharge air toward the second subspace SP2. For example, a portion of the first opening 721 discharges air toward the first subspace SP1, while the entire second opening 722 discharges air toward the second subspace SP2.

[0196] In one example, the width of the second opening 722 is greater than the width of the first opening 721, which facilitates achieving a second effective discharge area S2 that is greater than the first effective discharge area S1. Both the first opening 721 and the second opening 722 are strip-shaped, and their width and height can be defined with reference to the width and height definitions of the second air outlet 72.

[0197] In one example, both the first opening 721 and the second opening 722 are rectangular openings, and they can be connected. For example, see reference... Figure 11 and Figure 13, the first opening portion 721 and the second opening portion 722 communicate with each other, and the two together form a "convex"-shaped air outlet structure. The lens assembly LNSG is located on the air outlet side of the second air outlet 72. In one example, the above-mentioned first side edge of the lens assembly LNSG is arranged opposite to the first opening portion 721, that is, the boundary line between the first region and the second region of the second air outlet 72 falls on the first opening portion 721. Of course, in some other examples, the first side edge of the lens assembly LNSG may also be arranged opposite to the second opening portion 722; or, the first side edge of the lens assembly LNSG is arranged opposite to the boundary line between the first opening portion 721 and the second opening portion 722.

[0198] In some embodiments, in order to improve the arrangement stability of the lens assembly LNSG, as Figure 13 shown, the lens assembly LNSG may further include a fixing member FS, the fixing member FS is arranged opposite to the second air outlet 72, and both the edge of the light-transmitting portion GLS on a side close to the second air outlet 72 and the edge of the second lens LNS2 on a side close to the second air outlet 72 are fixed to the fixing member FS. For example, the fixing member FS is connected to the housing 1.

[0199] For example, the edge of the lens assembly LNSG on a side away from the second air outlet 72 may be directly or indirectly fixed to the housing 1.

[0200] It should be noted that when the lens assembly LNSG includes the light-transmitting portion GLS and the second lens LNS2, the edge of the lens assembly LNSG on the side away from the second air outlet 72 includes: the edge of the light-transmitting portion GLS on the side away from the second air outlet 72, and the edge of the second lens LNS2 on the side away from the second air outlet 72. When the lens assembly LNSG only includes the second lens LNS2 and does not include the light-transmitting portion GLS, the edge of the lens assembly LNSG on the side away from the second air outlet 72 is exactly the edge of the second lens LNS2 on the side away from the second air outlet 72.

[0201] It should be further noted that both the light-transmitting portion GLS and the second lens LNS2 can be of a polygonal structure, and both have a plurality of edges. The edge of the light-transmitting portion GLS (or the second lens LNS2) on the side close to the second air outlet 72 refers to the edge that is closest to the second air outlet 72 among the plurality of edges of the light-transmitting portion GLS (or the second lens LNS2). The edge of the light-transmitting portion GLS (or the second lens LNS2) on the side away from the second air outlet 72 refers to the edge that is farthest from the second air outlet 72 among the plurality of edges of the light-transmitting portion GLS (or the second lens LNS2).

[0202] For example, the fastener FS includes a first fastening part FS1 and a second fastening part FS2. The edge of the light-transmitting part GLS near the second air outlet 72 is fixed to the first fastening part FS1, and the edge of the second lens LNS2 near the second air outlet 72 is fixed to the second fastening part FS2.

[0203] In this embodiment, the fixing method of the first fixing part FS1 and the second fixing part FS2 is not limited. For example, the fixing method can be clamping, supporting, etc. For example, the first fixing part FS1 has a first fixing groove, and at least a portion of the edge of the light-transmitting part GLS near the second air outlet 72 is fixed in the first fixing groove; for example, the second fixing part FS2 has a second fixing groove, and at least a portion of the edge of the second lens LNS2 near the second air outlet 72 is fixed in the second fixing groove.

[0204] For example, both the first limiting groove and the second fixing groove are grooves with a certain length, width, and depth. The width direction of the first fixing groove is the thickness direction of the light-transmitting part GLS; the length direction of the first fixing groove is the extension direction of the edge of the light-transmitting part GLS near the second air outlet 72. For example, the depth direction of the first fixing groove is perpendicular to the length and width directions of the first fixing groove. Similarly, the width direction of the second fixing groove is the thickness direction of the second lens LNS2; the length direction of the second fixing groove is the extension direction of the edge of the second lens LNS2 near the second air outlet 72. For example, the depth direction of the second fixing groove is perpendicular to the length and width directions of the second fixing groove.

[0205] For example, the length of the first fixing groove can be greater than or equal to the length of the edge of the light-transmitting part GLS near the second air outlet 72; the width of the first fixing groove can be equal to or approximately equal to the thickness of the light-transmitting part GLS, thereby clamping the edge of the light-transmitting part GLS near the second air outlet 72 as a whole. The first fixing member FS1 can be made of a light-shielding material.

[0206] When the length of the first fixing groove is greater than or equal to the length of the edge of the light-transmitting part GLS near the second air outlet 72, and the first fixing member FS1 is made of light-shielding material, it can block the light that has not been polarized by the first polarizing element POL1, preventing it from shining into the display panel PNL and affecting the display effect.

[0207] For example, the length of the second fixing groove can be less than the length of the edge of the second lens LNS2 near the second air outlet 72, thereby clamping the portion of the second lens LNS2 near the second air outlet 72. For example, there are two second fixing parts FS2, which are spaced apart and fix the two ends of the edge of the second lens LNS2 near the second air outlet 72, respectively.

[0208] Since the second lens LNS2 generates more heat closer to its center when the projection device is working, the second fixing part FS2 is set at both ends of the edge of the second lens LNS2 near the second air outlet 72 to prevent the second fixing part FS2 from deforming due to the heat of the second lens LNS2.

[0209] For example, the first fixing part FS1 and the second fixing part FS2 can be formed as an integral structure.

[0210] In some embodiments, such as Figure 13 As shown, the fixing part FS also includes a limiting part FS3, which is used to limit the second reflector MR2 to ensure that the position of the second reflector MR2 remains stable within the housing. The limiting part FS3, the first fixing part FS1, and the second fixing part FS2 can be an integral structure.

[0211] For example, the limiting part FS3 has a limiting groove, and a portion of the edge of the second reflector MR2 near the second air outlet 72 is located in the limiting groove. For example, the edge of the second reflector MR2 near the second air outlet 72 is defined as a reference edge, and a limiting part FS3 is provided at one end of the reference edge along its length direction to limit one end of the reference edge; or, limiting parts FS3 are provided at both ends of the reference edge along its length direction to limit both ends of the reference edge; or the limiting parts FS3 are continuously distributed along the length direction of the reference edge. It should be noted that the limiting part FS3 can also limit the second reflector MR2 in other ways.

[0212] In some embodiments, the edge of the lens assembly LNSG near the second air outlet 72 may have a certain gap with the second air outlet 72 to facilitate the installation of the lens assembly LNSG. For example, the gap between the edge of the lens assembly LNSG near the second air outlet 72 and the second air outlet 72 is between [3mm, 5mm]. For example, the gap between the edge of the lens assembly LNSG near the second air outlet 72 and the second air outlet 72 is 3mm, 4mm, or 5mm.

[0213] In some embodiments, the ventilation area of ​​the second air inlet 71 is M times the sum of the first effective exhaust area S1 and the second effective exhaust area S2, where M is in the range [1, 1.2]. When M = 1, the air pressure of the second fan 7 can be stabilized. Preferably, M is set in the range (1, 1.2), in which case negative air pressure can be formed in the second fan 7, which is beneficial for drawing the air discharged from the second air outlet 72 into the second air inlet 71. For example, M is in the range (1, 1.1), or M is in the range [1.05, 1.15], or M is in the range [1.1, 1.2].

[0214] The second fan 7 includes a fan housing 7a and a centrifugal fan installed in the fan housing 7a. The second air inlet 71 is an air inlet opening installed on the fan housing 7a, and the ventilation area of ​​the second air inlet 7a is the area of ​​the air inlet opening.

[0215] The ventilation area of ​​the ventilation section 73 is K times the first effective exhaust area S1, where K is in the range of [1, 1.3]. This facilitates the extraction of air from the second air outlet 72 into the first subspace SP1 and then into the second air inlet 71. For example, K is in the range of (1, 1.1), or K is in the range of [1.05, 1.15]. Preferably, K is in the range of [1.1, 1.3], thereby maximizing the ventilation area of ​​the ventilation section 73 within a limited area on the fan housing 7a, allowing the air extracted from the second air outlet 72 into the first subspace SP1 to be extracted more smoothly into the second air inlet 71. For example, K = 1.2.

[0216] It should be noted that the ventilation area of ​​the ventilation section 73 refers to the cross-sectional area of ​​the airflow that can pass through the ventilation section 73. In one example, the ventilation section 73 includes one or more ventilation holes 731 penetrating the fan housing 7a1. If the ventilation holes 731 are cylindrical, then the ventilation area of ​​the ventilation section 73 is the sum of the ventilation areas of all ventilation holes 731, and the ventilation area of ​​each ventilation hole 731 is the cross-sectional area of ​​that ventilation hole 731 perpendicular to its axial direction.

[0217] In some preferred embodiments, the ventilation section 73 includes a plurality of ventilation holes 731, each ventilation hole 731 having an opening facing the first subspace SP1 and an opening facing the second subspace SP2. The two openings within the same ventilation hole 731 have the same area and shape. The shape of the ventilation hole 731 is not limited and can be rectangular, circular, triangular, trapezoidal, or other irregular shapes. The shape of the second air inlet 71 can be circular or other shapes. The plurality of ventilation holes 731 in the ventilation section 73 can be divided into two groups, located on either side of the centrifugal fan. For example, each group of ventilation holes 731 can be distributed along the arcuate contour of the centrifugal fan, with the two groups of ventilation holes 731 partially enclosing the centrifugal fan.

[0218] In some embodiments, such as Figure 10As shown, the accommodating space within the housing 1 also includes a third subspace SP3. When the first lens LNS1 is located on the side of the display panel PNL away from the second reflector MR2, at least a portion of the housing 1, the first reflector MR1, the projection lens 3, and the first lens LNS1 define the third subspace SP3. When the display panel PNL is located on the side of the first lens LNS1 away from the second reflector MR2, at least a portion of the housing 1, the first reflector MR1, the projection lens 3, and the display panel PNL define the third subspace SP3. Air in the third subspace SP3 may remain stationary.

[0219] Figure 14 This is a schematic diagram showing the positional relationship between the second reflector and the ventilation section in some exemplary embodiments of this disclosure, such as... Figure 14 As shown, along the direction perpendicular to the reflective surface of the second reflector MR2, the projection of the second reflector MR2 on the fan housing 7a does not overlap with at least part of the ventilation section 73, so as to ensure that the air in the first subspace SP1 can be blown to the first inner air duct CH' through the ventilation section 73.

[0220] In one example, the projection of the second reflector MR2 onto the fan housing 7a does not overlap with a portion of the ventilation section 73, but overlaps with another portion of the ventilation section 73. It should be noted that in this case, the ventilation area of ​​the ventilation section 73 is the cross-sectional area through which air can flow in the portion of the ventilation section 73 not blocked by the second reflector MR2.

[0221] In another example, the projection of the second reflector MR2 onto the fan housing 7a does not overlap with the ventilation section 73 at all, so as to ensure that the air in the first subspace SP1 can smoothly enter the first inner air duct CH'.

[0222] For example, the width of the reflective surface of the second mirror MR2 on the side closer to the lens assembly LNSG is greater than the width on the side farther from the lens assembly LNSG. For example, the width of the reflective surface of the second mirror MR2 tends to gradually decrease as the distance from the lens assembly LNSG increases. For example, the width of the reflective surface of the second mirror MR2 decreases as the distance from the lens assembly LNSG increases. This allows space to be provided for the ventilation section 73.

[0223] For example, the reflective surface of the second reflector MR2 is trapezoidal, having a first base MR21 and a second base MR22 that are parallel to each other, and a waist MR23 connecting the first base MR21 and the second base MR22. The length of the first base MR21 is greater than the length of the second base MR22. The first base MR21 is located in the first subspace SP1 near the lens assembly LNSG, and the second base MR22 is located in the second subspace SP2 away from the lens assembly LNSG. Along the direction perpendicular to the reflective surface of the second reflector MR2, the projection of the waist MR23 of the trapezoid onto the fan housing 7a is in contact with or adjacent to the ventilation section 73.

[0224] The reflective surface of the second reflector MR2 allows the light emitted by the light source assembly 2 to enter the display area of ​​the display panel PNL. Setting the reflective surface of the second reflector MR2 to be trapezoidal can avoid the ventilation part 73 without affecting the display effect.

[0225] In some embodiments, ventilation sections 73 are distributed on both sides of the second reflector MR2. Each ventilation section 73 includes multiple ventilation holes 731, and each side of the second reflector MR2 is provided with multiple ventilation holes 731, thereby allowing air in the first subspace to flow more evenly into the first inner air duct CH'. It should be understood that when each side of the second reflector MR2 is provided with multiple ventilation holes 731, the ventilation area of ​​the ventilation section 73 is the sum of the ventilation areas of all ventilation holes 731 on both sides. In one example, the number of ventilation holes 731 provided on both sides of the second reflector MR2 is the same, and the ventilation areas of the ventilation holes 731 on both sides are the same. For example, each side of the second reflector MR2 is provided with four ventilation holes 731, and the total ventilation area of ​​the four ventilation holes 731 on each side is equal to a preset value.

[0226] It should be noted that, in Figure 10 In the projection device shown, apart from the structures of the second fan 7 and the second reflector MR2, and the airflow direction within the airflow space, the rest of the structure in the projection device can be referred to the above. Figure 1A The projection device in the image will not be described in detail here.

[0227] In related technologies, the optical axis of the projection lens of the projection device coincides with the center of the projected image. This can easily lead to partial obstruction of the image, preventing it from being projected onto the projection screen. For example, when the projection device is placed on a support platform, the lower half of the image may be projected onto the platform instead of the projection screen, thus affecting the viewing experience. To address this issue, in some embodiments of this disclosure, the position of the optical elements in the projection device is adjusted to achieve off-axis projection, thereby adjusting the position of the projected image. When the projection device is used horizontally, compared to related technologies, the projected image is raised, resulting in a better viewing experience.

[0228] Figure 15 This is a schematic diagram of the optical elements in the projection device provided in some exemplary embodiments of this disclosure. The optical elements in the projection device in the above embodiments can all be based on... Figure 15 Arrange them in the correct positions. For example... Figure 15 As shown, in some embodiments of this disclosure, the optical axis L1 or equivalent optical axis L3 of the projection lens 3 has a first intersection point J with the display area of ​​the display panel PNL, and there is a non-zero distance d between the first intersection point J and the center of the display area of ​​the display panel PNL, thereby achieving off-axis projection in an "off-axis" manner, hereinafter referred to as "off-axis off-axis projection".

[0229] It should be noted that, in one example, a reflective element may not be provided between the display panel PNL and the projection lens 3, so that the light emitted from the display panel PNL does not undergo reflection (or, does not undergo bending) before reaching the projection lens 3. In this case, the positional relationship between the projection lens 3 and the display panel PNL satisfies the following: the optical axis L1 of the projection lens 3 and the display area of ​​the display panel PNL have a first intersection point J, and there is a non-zero distance d between the first intersection point J and the center of the display area of ​​the display panel PNL. In another example, a reflective element (e.g., a reflective element is provided between the display panel PNL and the projection lens 3) Figure 15As shown, light emitted from the display panel PNL is reflected by the first reflector MR1 and then enters the projection lens 3. In this case, the positional relationship between the projection lens 3 and the display panel PNL satisfies the following: there is a first intersection point J between the equivalent optical axis L3 of the projection lens 3 and the display area of ​​the display panel PNL, and there is a non-zero distance d between this first intersection point J and the center of the display area of ​​the display panel PNL. The so-called "equivalent optical axis L3" refers to the mirror extension of the optical axis of the lens 3, which can be understood as the axis of the optical axis L1 of the projection lens 3 after being reflected by the mirror surface of the first reflector MR1; in other words, the optical axis L1 of the projection lens 3 and the equivalent optical axis L3 intersect the reflective surface of the first reflector MR1 and are symmetrical about the normal L2 of the first reflector MR1. Therefore, the angle A1 between the optical axis L1 of the projection lens 3 and the normal L2 of the first reflector MR1 is equal to the angle A2 between the equivalent optical axis L3 of the projection lens 3 and the normal L2 of the first reflector MR1; the normal L2 of the first reflector MR1 refers to the straight line that passes through the intersection point M of the optical axis L1 of the projection lens 3 and the first reflector MR1 and is perpendicular to the reflective surface of the first reflector MR1.

[0230] In one example, the outer contour of the PNL display area on the display panel is rectangular; Reference Figure 15 A coordinate system is established with the PNL display area as the reference. The center O of the display area is taken as the origin of the coordinate system. The Z-axis of the coordinate system is the center normal of the display area, that is, a straight line passing through the center O and perpendicular to the display area. The Y-axis of the coordinate system points from the center O of the display area to the first side of the outer contour of the display area and is perpendicular to the first side. The X-axis of the coordinate system passes through the center O and is perpendicular to both the Y-axis and the Z-axis. That is, the X-axis points from the center O of the display area to the second side of the outer contour of the display area and is perpendicular to the second side. For example, the outer contour rectangle of the display area includes a long side and a short side. For example, the first side is a long side of the rectangle, and the second side is a short side of the rectangle.

[0231] For example, refer to Figure 15 With the first reflector MR1 in place, the Y-axis and the optical axis L1 of the projection lens 3 are located in the same plane.

[0232] For example, refer to Figure 15 With the first reflector MR1 present, the optical axis L1 of the projection lens 3 is in the same plane as the line containing the short side of the rectangle. In this way, the projection lens can project a horizontal image (length greater than height).

[0233] For example, the display panel PNL also includes a non-display area surrounding the display area.

[0234] For example, the display panel PNL also includes a bonding area located in the non-display area on one side of the long side of the outer contour rectangle of the display area.

[0235] For example, refer to Figure 15 In the presence of the first reflector MR1, the bonding area is located on the side of the display area of ​​the display panel PNL away from the projection lens 3, or the bonding area is located on the side of the display area of ​​the display panel PNL closer to the projection lens 3. This facilitates the arrangement of the display panel PNL driving circuit.

[0236] Preferably, in the presence of the first reflector MR1, the bonding area is located on the side of the display area of ​​the display panel PNL away from the projection lens 3, which facilitates the installation of the display panel PNL driving circuit.

[0237] In one example, the display area has a diagonal length of 4.45 inches and an aspect ratio of 16:9.

[0238] In one example, with the first reflector MR1 set, the equivalent optical axis L3 of the projection lens 3 is parallel to the center normal of the display area.

[0239] In one example, with the first reflector MR1 set, the equivalent optical axis L3 of the projection lens 3 is parallel to the Z-axis.

[0240] In some embodiments of this disclosure, when there is a first intersection point J between the optical axis L1 or equivalent optical axis L3 of the projection lens 3 and the display area of ​​the display panel PNL, and there is a non-zero gap d between the first intersection point J and the center of the display area of ​​the display panel PNL, the center of the image projected by the projection lens 3 onto the projection screen will deviate from the optical axis L1 or equivalent optical axis L3 of the projection lens 3, thus achieving off-axis projection. In practical applications, the size of the non-zero gap d can be adjusted as needed to ensure that the projected image is completely projected onto the projection screen, thereby improving the viewing experience.

[0241] In one example, the distance d between the first intersection point J and the center of the PNL display area of ​​the display panel does not exceed 25mm to ensure the display effect.

[0242] Preferably, d is in the range of [11mm, 16.5mm]. For example, d is 11mm, or 13mm, or 14mm, or 16mm, or 16.5mm. In this way, an off-axis ratio of 50% or close to 50% can be achieved.

[0243] Specifically, the off-axis ratio is defined as follows: In a projection system, let the center of the image be point A, and the intersection of the normal to the screen (or the plane containing the screen) passing through the lens optical center and the screen (or the plane containing the screen) be point B. When points A and B coincide, it is a non-off-axis projection (off-axis ratio of 0%). When points A and B do not coincide, it is an off-axis projection. The distance between A and B is called the "off-axis amount". In practical applications, the focus is generally on off-axis projection in the height direction, so the "off-axis ratio" can be defined as the ratio of the "off-axis amount" to the half-height of the image.

[0244] In one example, as described above, the projection device includes a first lens LNS1 and a second lens LNS2, wherein the first lens LNS1 can be a convex lens. In some embodiments, the first lens LNS1 can be a Fresnel lens or an aspherical mirror, preferably a Fresnel lens. The second lens LNS2 is a convex lens. In some embodiments, the second lens LNS2 can be a Fresnel lens or an aspherical mirror, preferably a Fresnel lens.

[0245] Figure 16 This is a schematic diagram of the optical path when the display surface of the display panel is parallel to the plane where the second lens is located, as shown below. Figure 16 As shown, when implementing off-axis projection, if the extension surface of the display panel PNL is parallel to the plane where the second lens LNS2 is located, the light illuminating the projection lens 3 cannot converge at the center of the aperture stop, i.e., the center of the projection lens 3, resulting in a smaller light flux and thus a vignetting problem, leading to poor display uniformity. To solve this problem, in the embodiments of this disclosure, as follows... Figure 15 As shown, the extended surface of the display panel PNL intersects the plane where the second lens LNS2 is located at the second intersection point P, and there is a first included angle A8 between the extended surface of the display panel PNL and the plane where the second lens LNS2 is located.

[0246] It should be noted that the PNL extension surface of the display panel refers to the extension surface of the PNL display surface of the display panel.

[0247] It should be noted that the plane containing the second lens LNS2 can be understood as a plane passing through the optical center of the second lens and perpendicular to the optical axis of the second lens. When the second lens LNS2 is a Fresnel lens, the plane containing the second lens LNS2 is parallel to the extended plane of the second lens LNS2.

[0248] The first included angle A8 is within the range of (0, 10°), thus achieving a better lighting effect. Preferably, the equivalent optical axis L3 of the projection lens 3 is perpendicular to the display surface of the display panel PNL, and A8 = A4 - 90°, where A4 is the angle between the portion of the second lens LNS2 away from the second intersection point P and the equivalent optical axis L3 of the projection lens 3.

[0249] Figure 17 This is a schematic diagram illustrating the telecentric optical path of the projection device implemented in some exemplary embodiments of this disclosure, such as... Figure 17 As shown, when there is the first included angle A8 between the extended surface of the display panel PNL and the plane where the second lens LNS2 is located, it is equivalent to the light no longer entering the display panel PNL perpendicularly, but entering at an angle, so that the light illuminating the projection lens 3 can be close to or even pass through the center of the projection lens 3, realizing the object-side telecentric optical path.

[0250] Preferably, the first included angle A8 is within the range of (0, 7°). More preferably, with reference to Figure 15 and Figure 17 The first included angle A8 can be 5° so that the light can be focused at the center of the projection lens 3, thereby maximizing the light flux of the projection lens 3 and improving the uniformity of the display.

[0251] Figure 18 for Figure 15 The schematic diagram shown depicts the display panel, second lens, first reflector, and projection lens in the projection device, combined with... Figure 15 and Figure 18 As shown, in some embodiments, the distance D1 between the display panel PNL on the side of the first intersection point J and the plane where the second lens LNS2 is located is greater than the distance D2 between the display panel PNL on the side away from the center of the display area of ​​the display panel PNL from the first intersection point J and the plane where the second lens LNS2 is located, so that the light enters the display panel PNL at an angle, thereby making the convergence point of the light illuminating the projection lens 3 located at or closer to the center of the projection lens 3.

[0252] In some embodiments, such as Figure 15 As shown, the projection device includes a first reflector MR1, which reflects light emitted from the display panel PNL into the projection lens 3. The first reflector MR1 can be a plane reflector. The optical axis L1 and the equivalent optical axis L3 of the projection lens 3 intersect at a point on the reflective surface of the first reflector MR1, and the normal L2 of the first reflector MR1 passes through the intersection point. The optical axis L1 and the equivalent optical axis L3 of the projection lens 3 are symmetrically distributed about the normal L2 of the first reflector MR1. Let A1 be the angle between the optical axis L1 of the projection lens 3 and the normal L2 of the first reflector MR1, and let A2 be the angle between the equivalent optical axis L3 of the projection lens 3 and the normal L2 of the first reflector MR1. Then A1 = A2.

[0253] In some embodiments, reference Figure 15 The optical axis L1 of the projection lens 3 is parallel to the reference plane n. Preferably, the equivalent optical axis L3 of the projection lens 3 is parallel to the center normal of the display area PNL of the display panel, which can achieve better performance.

[0254] It should be noted that the reference plane n can be understood as the placement plane or suspension plane of the projection device during normal operation. It is understood that the normal placement method of the projection device can be clearly indicated on the projection device or in the product manual; for example, users can easily find the most recommended placement method on the product, which is the normal placement method. For example, a support surface and / or foot pads are provided on one side of the projection device to guide the user to place the projection device on the reference plane; for example, a suspension device is provided on one side of the projection device to guide the user to suspend and fix the projection device to the reference plane (e.g., the ceiling). In some embodiments, the reference plane n... Figure 6A The reference plane n is parallel to the ground plane GND; in this case, preferably, the projection screen is set perpendicular to the ground plane GND, which can achieve a better display effect.

[0255] In some embodiments, there is a certain angle between the optical axis L1 of the projection device and the reference plane n, so that off-axis projection can be achieved by rotating the angle, hereinafter referred to as "rotation angle off-axis projection". Figure 19 This is a schematic diagram illustrating the principle of off-axis projection. Off-axis projection can be understood as the optical axis of projection lens 3 no longer being perpendicular to the imaging plane (or the plane where the projection screen is located), such as... Figure 19 As shown, the optical axis of the projection lens 3 initially extends along the dotted line L9'. By rotating, the optical axis of the projection lens 3 extends along L9. This method can also be used to adjust the position of the projected image.

[0256] In some embodiments of this disclosure, the off-axis effect can be achieved by simply using a rotation angle.

[0257] In some embodiments of this disclosure, both off-axis projection and rotation angle off-axis projection can be used simultaneously to achieve a larger off-axis ratio.

[0258] In some embodiments, such as Figure 15 As shown, the optical axis L1 of the projection lens 3 has an elevation angle A9 relative to the reference plane n in the projection beam emission direction. This elevation angle can be understood as the light rays emitted along the optical axis L1 of the projection lens 3 being obliquely upward relative to the reference plane when the projection device is placed on the reference plane n. The elevation angle A9 can be determined based on the desired off-axis effect; a larger elevation angle A9 results in a higher off-axis ratio. In some embodiments, the elevation angle A9 is within the range of (0, 15°) to achieve good image quality. Preferably, the equivalent optical axis L3 of the projection lens 3 is parallel to the center normal of the display area of ​​the PNL display panel, thus achieving better imaging results.

[0259] Preferably, the elevation angle A9 is within the range of (0, 10°) to achieve better image quality. For example, the elevation angle A9 is 5°, or 6°, or 7°, or 8°, or 9°, or 10°.

[0260] In practical applications, the projection device can be placed on the ground plane GND, so that the light rays emitted along the optical axis L1 of the projection lens 3 illuminate the projection screen obliquely upwards relative to the ground plane GND. Alternatively, the projection device can be inverted (relative to the case where it is placed on the ground plane GND) and suspended from a support frame (or ceiling), so that the light rays emitted along the optical axis L1 of the projection lens 3 illuminate the projection screen obliquely downwards relative to a reference plane. For example, the projection screen can be set perpendicular to the ground plane GND.

[0261] Although it is possible to achieve angular deflection when the optical axis L1 of the projection lens 3 forms an angle with the reference plane n, however, as... Figure 19 As shown, when the rotation angle is off-axis, the image distances of points A and B on the projection screen are similar, approximately L2'; the image distance of point C is L1'; and the image distance of point D is L3'. Therefore, the lateral magnification of the actual image points is different, resulting in trapezoidal distortion. To ensure the display effect of the projected image, optical trapezoidal correction is required. The purpose of trapezoidal correction is to make the lateral magnification of all points on the display panel the same. When the image distances of different points are different, the ratio of image distance to object distance can be kept constant by changing the object distance. For projection lens 3, its object plane is the virtual image of the display panel PNL about the first lens LNS1, which is a virtual object for projection lens 3. By rotating the first lens LNS1, the virtual image of the display panel PNL can be rotated, that is, the virtual object of projection lens 3 rotates. This can adjust the ratio of image distance to object distance of each point on the display panel, thereby improving the trapezoidal distortion problem.

[0262] To achieve trapezoidal correction, combined with Figure 15 and Figure 18 As shown, in some embodiments of this disclosure, there is an angle A3 between the equivalent optical axis L3 of the projection lens 3 and the plane where the first lens LNS1 is located, where A3 can be in the range of [75°, 90°). The distance D3 between the end of the first lens LNS1 closer to the projection lens 3 and the display panel PNL is greater than the distance D4 between the end of the plane where the first lens LNS1 is located away from the projection lens 3 and the display panel PNL. This situation is equivalent to rotating the first lens LNS1, thereby rotating the virtual image of the display panel PNL and thus improving the trapezoidal distortion problem.

[0263] It should be noted that the plane containing the first lens LNS1 can be understood as a plane passing through the optical center of the first lens LNS1 and perpendicular to the optical axis of the first lens LNS1. When the first lens LNS1 is a Fresnel lens, the plane containing the first lens LNS1 is parallel to the extended plane of the first lens LNS1.

[0264] In one example, A3 can be set in the range of [80°, 90°) to further improve the problem of trapezoidal distortion.

[0265] Preferably, A3 = 90° - A9, which can further improve the problem of trapezoidal distortion. For example, A9 = A0 + A7 = 5°, A3 = 85°.

[0266] In some embodiments, the extension surface of the display panel PNL is parallel to the reference plane n.

[0267] In some embodiments, a second included angle A7 exists between the extended surface of the display panel PNL and the reference plane n, and the value of the second included angle A7 is within the range of (0, 30°). Preferably, the height of the end of the display panel PNL closer to the projection lens 3 relative to the reference plane n is higher than the height of the end of the display panel PNL farther from the projection lens 3 relative to the reference plane n. This allows for a more compact arrangement of the optical elements in the projection device, which is beneficial for reducing the size of the projection device.

[0268] In some embodiments, the angle between the equivalent optical axis L3 of the projection lens 3 and the normal of the first reflector MR1 is in the range of [30°, 60°]. Preferably, the angle between the equivalent optical axis L3 of the projection lens 3 and the normal of the first reflector MR1 is in the range of [35°, 50°], which helps to reduce the size of the projection device.

[0269] Let A1 be the angle between the optical axis L1 of the projection lens 3 and the normal of the first reflector MR1, and let A2 be the angle between the equivalent optical axis L3 of the projection lens 3 and the normal of the first reflector MR1. Then A1 = A2. Let the angle between the optical axis L1 of the projection lens 3 and the extension surface of the display panel PNL be the third angle A0. Define the projection lens 3 as being in an upward-tilting state relative to the extension surface of the display panel PNL in the direction of projection beam emission (i.e., Figure 15 When the optical axis of the projection lens 3 is tilted relative to the reference plane n (as shown in the diagram), that is, when the tilt of the optical axis of the projection lens 3 relative to the reference plane n is greater than the tilt of the extended surface of the display surface PNL relative to the reference plane, A0 is a positive value; the projection lens 3 is defined as being in a downward tilt state relative to the reference plane n in the projection beam emission direction (i.e., when the optical axis of the projection lens 3 is tilted relative to the reference plane n). Figure 15When the left end of the projection lens 3 is adjusted to be lower than the right end, that is, when the tilt of the optical axis of the projection lens 3 relative to the reference plane n is less than the tilt of the extension surface of the display surface PNL relative to the reference plane n, A0 is a negative value; then the above-mentioned elevation angle A9 = A0 + A7. After determining the elevation angle A9 as needed, A7 can be set to a larger value, at which point the value of A0 is smaller. Since A1 + A2 = A0 + 90°, when the value of A0 is smaller, the values ​​of A1 and A2 are also smaller (at this time, it is equivalent to rotating the first lens LNS1, the light source assembly 2, and all the components between them clockwise around point M as a whole), which helps to reduce the size of the projection device.

[0270] In one example, the Y-axis lies in the same plane as the optical axis L1 of the projection lens 3.

[0271] In some embodiments, once the elevation angle A9 is determined, the second included angle A7 can be set to a larger value not exceeding 30°. Furthermore, when the tilt of the optical axis L1 of the projection lens 3 relative to the reference plane n is greater than the tilt of the extension surface of the display panel PNL relative to the reference plane n, the third included angle A0 is defined as a positive value and set within the range of (0, 30°). When the tilt of the optical axis L1 of the projection lens 3 relative to the reference plane n is less than the tilt of the extension surface of the display panel PNL relative to the reference plane n, the third included angle A0 is defined as a negative value and set within the range of [-30°, 0). Accordingly, the values ​​of A1 and A2 are both within the range of [30°, 60°], which helps to optimize the component layout in the projection device and reduce the size of the projection device.

[0272] Preferably, the second included angle A7 can be set to a larger value within a range not exceeding 30°, for example, the second included angle A7 can be set within the range of (0, 20°). When the tilt of the optical axis L1 of the projection lens 3 relative to the reference plane n is greater than the tilt of the extension surface of the display panel PNL relative to the reference plane n, the third included angle A0 is set within the range of (0, 10°); correspondingly, the values ​​of A1 and A2 are both within the range of (45°, 50°). When the tilt of the optical axis L1 of the projection lens 3 relative to the reference plane n is less than the tilt of the extension surface of the display panel PNL relative to the reference plane n, the third included angle A0 is set within the range of [-20, 0), correspondingly, the values ​​of A1 and A2 are both within the range of [35°, 45°).

[0273] In one example, the elevation angle of projection lens 3 is set to 5° to reduce the problem of image abnormalities caused by excessive off-axis rate due to the rotation angle. At this time, A0 + A7 = 5°, and in order to reduce the size of the projection device, A7 is set to 18° and A0 is set to -13°. At this time, A1 = A2 = 38.5°.

[0274] In some embodiments, such as Figure 15 As shown, the light source assembly 2 includes a condenser lens 23, which is disposed on the light-emitting side of the light-emitting element 21 to converge the light emitted by the light-emitting element 21. The condenser lens 23 is, for example, a plano-convex lens.

[0275] In some embodiments, the optical axis of the condenser lens 23 is coaxial or nearly coaxial with the central axis L6 of the light-emitting element 21. Specifically, the optical axis of the condenser lens 23 is parallel to the central axis L6 of the light-emitting element 21, and the distance between them is between [0, 2] mm. Here, the central axis L6 of the light-emitting element 21 refers to a straight line passing through the center of the light-emitting surface of the light-emitting element 21 and perpendicular to the light-emitting surface.

[0276] In some embodiments, such as Figure 15 As shown, the projection device includes a second reflector MR2, which reflects the light emitted from the light-emitting element 21 into the display panel PNL. Specifically, the light emitted from the light-emitting element 21 is first converged by the condenser lens 23 and then directed towards the second reflector MR2. The light is reflected by the second reflector MR2 and then illuminates the second lens LNS2. After collimation by the second lens LNS2, the light is directed towards the display panel PNL.

[0277] In some embodiments, the equivalent optical axis of the light-emitting element 21 can be defined as follows: the central axis of the light-emitting element 21 and the equivalent optical axis of the light-emitting element 21 intersect at a point on the reflecting surface of the second reflector MR2, the normal of the second reflector MR2 passes through this intersection point, and the central axis of the light-emitting element 21 and the equivalent optical axis of the light-emitting element 21 are symmetrically distributed about the normal axis of the second reflector MR2. An angle A50 exists between the central axis of the light-emitting element and the normal of the second reflector MR2; an angle A60 exists between the equivalent optical axis of the light-emitting element 21 and the normal of the second reflector MR2; A50 = A60.

[0278] In some embodiments, A50 is set within the range of [35°, 55°], which helps to reduce the overall size of the projection device. Preferably, A50 is set within the range of [35°, 55°].

[0279] In some embodiments, the central axis of the light-emitting element 21 is arranged perpendicular to the plane where the second lens LNS2 is located, which helps to reduce the overall size of the projection device and at the same time reduces the generation of stray light.

[0280] In some embodiments, the equivalent optical axis of the light-emitting element 21 passes through or is close to the center of the display area of ​​the display panel PNL. Specifically, the distance between the equivalent optical axis of the light-emitting element 21 and the center of the display area of ​​the display panel PNL is between [0, 5] mm, so that the center of the display panel PNL has the highest brightness and the display effect is improved.

[0281] In some embodiments, the light source assembly 2 includes a condenser lens 23, such as Figure 15 As shown, the equivalent optical axis L4 of the condenser lens 23 can be defined as follows: the optical axis L6 of the condenser lens 23 and the equivalent optical axis L4 of the condenser lens 23 intersect at a point on the reflecting surface of the second mirror MR2, and the normal L4 of the second mirror MR2 passes through the intersection point. The optical axis L6 and the equivalent optical axis L4 of the condenser lens 23 are symmetrically distributed about the normal L4 of the second mirror MR2. An angle A5 exists between the optical axis L6 of the condenser lens 23 and the normal L5 of the second mirror MR2; an angle A6 exists between the equivalent optical axis L4 of the condenser lens 23 and the normal L5 of the second mirror MR2; A5 = A6.

[0282] In some embodiments, A5 is set within the range of [35°, 55°], which helps to reduce the overall size of the projection device. Preferably, A5 is set within the range of [35°, 55°].

[0283] In a specific example of this disclosure, the optical axis L1 of the projection lens 3 and the extension surface of the display panel PNL are both parallel to the reference plane n; A8 = 5°; A1 and A2 are both set to 45°; A3 is set to 90°; A50 = A60 = 41°; L3 is perpendicular to the display surface of the display panel PNL; d = 13.85mm. In this way, a satisfactory display effect can be achieved.

[0284] refer to Figure 15 The optical axis L6 of the condenser lens 23 intersects the second reflector MR2 at point N; the normal to the second reflector MR2 is a straight line passing through point N and perpendicular to the reflecting surface of the second reflector MR2; the equivalent optical axis of the condenser lens 23 is a straight line that is symmetrical about L5.

[0285] In some embodiments, there is an angle A6' between the reflecting surface of the second reflector MR2 and the plane where the second lens LNS2 is located. Preferably, A5 = A6 = A6', so that the equivalent optical axis of the condenser lens 23 is set perpendicular to the plane where the second lens LNS2 is located, which helps to reduce the overall size of the projection device and at the same time reduces the generation of stray light.

[0286] For example, setting A6' within the range of [35°, 55°] helps to reduce the overall size of the projection device and also reduces the generation of stray light. Preferably, A6' is set within the range of [35°, 45°]. For example, A6' is set to 35°, or 40°, or 41°, or 45°.

[0287] In some examples, there is an angle A5' between the optical axis of the condenser lens 23 and the reflecting surface of the second mirror MR2, where A5' = 90° - A5, and thus the sum of A5' and A6' mentioned above is 90°.

[0288] In some embodiments, the equivalent optical axis L4 of the condenser lens 23 passes through or is close to the center of the display area of ​​the display panel PNL. Specifically, the distance between the equivalent optical axis L4 of the condenser lens 23 and the center of the display area of ​​the display panel PNL is between [0, 5] mm, so that the center brightness of the display panel PNL is the highest, thereby improving the display effect.

[0289] In a specific example of this disclosure, the optical axis L1 of the projection lens 3 and the extension surface of the display panel PNL are both parallel to the reference plane n; A8 = 5°; A1 and A2 are both set to 45°; A3 is set to 90°; A5 = A6 = 41°; L3 is perpendicular to the display surface of the display panel PNL; d = 13.85mm. In this way, a satisfactory display effect can be achieved.

[0290] In some embodiments, L1, L3, L4, L6 and the Y-axis are all on the same plane, thus achieving a satisfactory display effect.

[0291] In some embodiments, such as Figure 15 As shown, the second lens LNS2 is located on the side of the light-transmitting part GLS away from the display panel PNL, and the second lens LNS2 is located on the side of the first polarizing element away from the display panel PNL.

[0292] In some embodiments, the shape of the light-transmitting portion GLS and the shape of the second lens LNS2 can both be the same as the shape of the display panel PNL, for example, both being rectangular. The size of the light-transmitting portion can be the same as the size of the second lens LNS2. The optical axis of the second lens LNS2 passes through the center of the light-transmitting portion, or the distance between the optical axis of the second lens LNS2 and the center of the light-transmitting portion is sufficiently small; specifically, the distance between the optical axis of the second lens LNS2 and the center of the light-transmitting portion GLS is between [0, 10] mm.

[0293] It should be noted that if the relative positional relationship (including relative distance and included angle) between optical elements can be determined according to the above disclosure, the relative positional relationship between optical elements is also within the protection scope of this disclosure.

[0294] refer to Figure 20A When the reference plane n is parallel to the ground plane GND, the projection device is a vertical projection device.

[0295] In some embodiments, an angle may exist between the reference plane n and the ground plane GND. Figure 20BWhen the reference plane n is perpendicular to the ground plane GND, the projection device is a horizontal projection device. It is understood that when the projection device is changed from a vertical projection device to a horizontal projection device, the relative positional relationship between the optical elements is not changed. Therefore, the horizontal projection device based on the concept of this disclosure is also within the protection scope of this disclosure.

[0296] Figure 21A This is a partial optical path diagram of a projection device according to some exemplary embodiments of the present disclosure. Figure 21B This is a front view of the light-emitting element and its base of a projection device according to some exemplary embodiments of the present disclosure. Please refer to... Figure 21A , Figure 21B The light source assembly 2 includes a light-emitting element 21 and a condenser lens 23. The light-emitting element 21 includes a light-emitting area 211, which refers to the effective light-emitting area of ​​the light-emitting element. (Reference) Figure 21B The light-emitting element 21 includes a light-emitting area 211. For example, the light-emitting element 21 may include only one light-emitting chip, which has a light-emitting boundary that defines the light-emitting area 211. Alternatively, the light-emitting element 21 may include multiple light-emitting chips, whose light-emitting boundaries share a common outer contour that defines the light-emitting area 211. For example, the light-emitting element 21 may include multiple light-emitting chips arranged in an array, forming a rectangular array; therefore, the light-emitting area of ​​the light-emitting element 21 is the rectangular contour formed by the light-emitting boundaries of the multiple light-emitting chips.

[0297] A condenser lens 23 is disposed on the light-emitting side of the light-emitting element 21 and located opposite to the light-emitting side of the display panel PLN, used to concentrate or shape the light emitted by the light-emitting element 21. After being concentrated or shaped by the condenser lens 23, the light emitted by the light-emitting element 21 enters the projection lens 3 through the display panel and exits from the projection lens. Additionally, as... Figure 21B As shown, the light source assembly 2 may also include a light-emitting element base 22, with the light-emitting element 21 located on the light-emitting element base 22.

[0298] For example, such as Figure 21B As shown, the light-emitting area 211 includes mutually perpendicular first extending directions (e.g., Figure 21B (in the Z' direction) and the second extension direction (e.g., Figure 21BThe aspect ratio of the maximum length L_7 of the light-emitting area 211 in the first extension direction to the maximum width L_8 in the second extension direction is a first aspect ratio, which is greater than or equal to the aspect ratio of the display area of ​​the display panel. It should be noted that the aforementioned first aspect ratio is the maximum outline dimension of the light-emitting area 211 in two mutually perpendicular directions (i.e., the first extension direction and the second extension direction). The aspect ratio of the display area of ​​the display panel is the outline dimension of the display area in two mutually perpendicular directions (e.g., the width and height of the image generated by the display area, where the width divided by the height equals the aspect ratio).

[0299] This embodiment improves light energy utilization by making the first aspect ratio greater than or equal to the aspect ratio of the display area of ​​the display panel. Furthermore, by using a condenser lens to focus or shape the light emitted by the light-emitting element 21, the light illuminating the display area of ​​the display panel can be made more collimated and uniform, thereby improving image uniformity.

[0300] In some optional embodiments, the ratio of the first aspect ratio to the aspect ratio of the display area of ​​the display panel is greater than 1 and less than 1.2. By adopting this ratio range, light energy utilization can be improved. More preferably, the ratio of the first aspect ratio to the aspect ratio of the display area of ​​the display panel is greater than 1 and less than 1.15. This ratio range has the best effect on improving light energy utilization.

[0301] In some optional embodiments, the display area of ​​the display panel PLN is rectangular, and correspondingly, the aspect ratio of the display area is the ratio of the length of the longer side to the length of the shorter side of the rectangle. The outline of the light-emitting area 211 can be rectangular, for example... Figure 21B As shown, the length of the long side of the rectangle is the maximum length L_7 in the first extension direction; the length of the short side of the rectangle is the maximum width L_8 in the second extension direction, that is, the first aspect ratio is the ratio of the length of the long side to the length of the short side of the rectangle. Optionally, the four corners of the rectangular outline of the light-emitting area 211 are rounded, and the arc corresponding to each rounded corner smoothly transitions between the corresponding long and short sides. In another optional embodiment, the outline of the light-emitting area 211 can also be elliptical, with the length of the major axis of the ellipse being the maximum length in the first extension direction; the length of the minor axis of the ellipse being the maximum width in the second extension direction, that is, the first aspect ratio is the ratio of the length of the major axis to the length of the minor axis of the ellipse. Of course, in practical applications, the outline of the light-emitting area can also be circular, that is, the first aspect ratio is 1.

[0302] In some alternative embodiments, the extension direction of the long side of the display panel is the same as or approximately the same as the first extension direction. This ensures good image uniformity along the long side of the display panel. "Approximately the same" can be understood as a deviation of less than 10° between the two extension directions.

[0303] In some optional embodiments, the outline of the light-emitting area 211 is rectangular, with the long side length ranging from 10mm to 15mm, preferably 13.6mm ± 0.2mm, and the short side length ranging from 6mm to 12mm, preferably 8.9mm ± 0.2mm; or, the outline of the light-emitting area is elliptical, with the major axis length ranging from 10mm to 15mm and the minor axis length ranging from 6mm to 12mm. By adopting the above-mentioned outline size range of the light-emitting area according to its outline shape, better light energy utilization and imaging uniformity can be obtained.

[0304] Figure 22A A three-view diagram of a condenser lens of a projection apparatus according to some exemplary embodiments of the present disclosure. Figure 22B This is another three-view drawing of the condenser lens of a projection device according to some exemplary embodiments of the present disclosure. In some alternative embodiments, please refer to [the following text is also included]. Figure 22A and Figure 22B The aforementioned condenser lens 23 includes a plano-convex lens having a lens plane 231 and a lens convex surface 232 that are opposite to each other; the lens plane 231 is opposite to the light-emitting side of the light-emitting element 21 and is spaced apart; and the lens plane 231 includes a third extending direction that is perpendicular to each other (e.g., Figure 22A and Figure 22B (in the Z' direction) and the fourth extension direction (e.g. Figure 22A and Figure 22B The third extension direction is the same as the first extension direction (e.g., the Y' direction in the middle); the third extension direction is the same as the first extension direction mentioned above ... Figure 21B The fourth extension direction is parallel to the second extension direction (e.g., the Z' direction in the second extension direction). Figure 21BThe plano-convex lens is parallel to the Y' direction in the first extension direction; the ratio of the maximum length L_1 of the lens plane 231 in the third extension direction to the maximum length of the light-emitting area in the first extension direction is in the range of 2.5-3.5, and the ratio of the maximum width L_3 of the lens plane 231 in the fourth extension direction to the maximum width of the light-emitting area in the second extension direction is in the range of 3-4. As an intermediate medium in the light propagation path, the outline dimensions of the plano-convex lens in the two mutually perpendicular directions (i.e., the third extension direction and the fourth extension direction) of the lens plane 231 should be larger than the outline dimensions of the corresponding direction of the light-emitting area, while also obtaining a more ideal lens surface shape. This not only improves the collimation of the light illuminating the display area of ​​the display panel, but also further improves the light energy utilization and imaging uniformity. In a preferred embodiment, the ratio of the maximum length L_1 of the lens plane 231 in the third extension direction to the maximum length of the light-emitting area in the first extension direction is 3.3, and the ratio of the maximum width L_3 of the lens plane 231 in the fourth extension direction to the maximum width of the light-emitting area in the second extension direction is 3.8; in another preferred embodiment, the ratio of the maximum length in the first extension direction is 2.7, and the ratio of the maximum width L_3 of the lens plane 231 in the fourth extension direction to the maximum width of the light-emitting area in the second extension direction is 3.2; thus, a more optimized display effect can be achieved.

[0305] It should be noted that in practical applications, the condenser lens 23 is not limited to using a plano-convex lens; other lens structures can also be used.

[0306] In some alternative embodiments, please refer to Figure 22A The lens plane 231 is rectangular, with the longer side being the maximum length L_1 in the third extension direction and the shorter side being the maximum width L_3 in the fourth extension direction. Alternatively, please refer to... Figure 22B The lens plane 231 can also be elliptical, with the major axis of the ellipse being the maximum length L_1 in the third extension direction and the minor axis of the ellipse being the maximum width L_3 in the fourth extension direction.

[0307] In some optional embodiments, the maximum length L_1 of the lens plane 231 in the third extension direction is in the range of 36mm-45mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is in the range of 28mm-35mm, and the maximum thickness L_5 of the plano-convex lens is in the range of 15mm-20mm. Preferably, the maximum length L_1 of the lens plane 231 in the third extension direction is in the range of 43mm-44mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is in the range of 33mm-34mm, and the maximum thickness L_5 of the plano-convex lens is in the range of 17mm-19mm. Alternatively, the maximum length L_1 of the lens plane 231 in the third extension direction is in the range of 36.5mm-38mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is in the range of 28.5mm-30mm, and the maximum thickness L_5 of the plano-convex lens is in the range of 15mm-16mm.

[0308] By adopting the aforementioned contour dimensions, the lens plane 231 can not only improve the collimation of the light illuminating the display area of ​​the display panel, but also further improve the light energy utilization and imaging uniformity.

[0309] In some alternative embodiments, such as Figure 21A As shown, the distance D_1 between the light-emitting area and the lens plane 231 is within the range of 1.5mm-4mm. The distance D_1 should not be too large, otherwise it will lead to low light energy utilization, ultimately affecting the brightness of the image. Conversely, the distance should not be too small, otherwise it will cause light spots on the display area of ​​the display panel and dark corners, ultimately affecting image uniformity and even causing vignetting. Therefore, by setting the distance D_1 between the light-emitting area and the lens plane 231 within the above-mentioned range, these defects can be avoided.

[0310] In some other alternative embodiments, such as Figure 22A and Figure 22B As shown, the condenser lens 23 also includes a lens base 233 located on the side of the plano-convex lens near the light-emitting element 21. The lens base 233 is in contact with the plano-convex lens to facilitate its installation and fixation. The distance between the light-emitting area and the lens base 233 is within the range of 1.5mm-4mm, thus achieving good light utilization efficiency and uniform display brightness. Optionally, the surface of the lens base 233 facing away from the light-emitting area is flush with the lens plane to facilitate processing and make assembly more stable. Optionally, the orthographic projection of the plano-convex lens onto the extension surface of the lens base 233 is located inside the lens base 233.

[0311] In some optional embodiments, considering factors such as the outline dimensions of the plano-convex lens, manufacturing feasibility, and structural design requirements of the projection device, the maximum length L_2 of the lens base 233 in the third extension direction is in the range of 45mm to 50mm; the maximum width L_4 of the lens base 233 in the fourth extension direction is in the range of 34mm to 38mm; and the thickness L_6 of the lens base 233 is in the range of 1.2mm to 3mm. Preferably, the maximum length L_2 of the lens base 233 in the third extension direction is in the range of 47mm to 49mm; the maximum width L_4 of the lens base 233 in the fourth extension direction is in the range of 35mm to 37mm; and the thickness L_6 of the lens base 233 is in the range of 1.6mm to 2.2mm.

[0312] In one optional embodiment, the outer contour of the lens base 233 is 0.5mm-3mm wider than the outer contour of the plano-convex lens projected onto the lens base 233, which facilitates the draft molding of the plano-convex lens. Preferably, the outer contour of the lens base 233 is 1mm-2mm wider than the outer contour of the plano-convex lens projected onto the lens base 233, which reduces the processing difficulty, makes the assembly more stable, and reduces the volume occupied by the lens base 233.

[0313] In some optional embodiments, considering factors such as the outline size of the plano-convex lens, processing feasibility, and structural design requirements of the projection device, the outline of the lens base 233 is rectangular, and each of the four corners of the rectangle includes one or more arc segments. The radius R of the arc segments is in the range of 4mm-18mm, so as to facilitate processing and make the assembly more stable.

[0314] Figure 23 This is another outline view of the lens base of a projection device according to some exemplary embodiments of the present disclosure. In some alternative embodiments, such as... Figure 23 As shown, the rectangular outline of the lens base 233 has a first transition fillet (corresponding to the arc radius R) and a second transition fillet (corresponding to the arc radius R2) between the rounded corner (corresponding to the arc radius R1) and the two adjacent sides, and the arc radius R1 of the first transition fillet is smaller than the arc radius R2 of the second transition fillet; wherein, the first transition fillet is adjacent to the long side, and the second transition fillet is adjacent to the short side; the arc radius R of the fillet is 10.5mm±1mm; the arc radius R1 of the first transition fillet is 22.5mm±1mm; and the arc radius R2 of the second transition fillet is 28.5mm±1mm.

[0315] In some alternative embodiments, the three views of the plano-convex lens are as follows: Figure 22A and Figure 22BAs shown, the radius R of the four rounded corners of the rectangular outline of the lens base 233 is 12.5mm ± 1mm.

[0316] In one specific embodiment, such as Figure 22A As shown, the maximum length L_1 of the lens plane 231 in the third extension direction is in the range of 43.6mm-44.4mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is in the range of 33.6mm-34.4mm, and the maximum thickness L_5 of the plano-convex lens is in the range of 18.6mm-19.4mm. In this way, the projected image can obtain better brightness and uniformity.

[0317] In one specific embodiment, such as Figure 22A As shown, the maximum length L_1 of the lens plane 231 in the third extension direction is 44mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is 34mm, and the maximum thickness L_5 of the plano-convex lens is 19mm. The values ​​of L_1, L_3, and L_5 can be proportionally reduced or enlarged by up to 10%, and the resulting plano-convex lens can also meet the design requirements. Optionally, the maximum length of the plano-convex lens plane in the third extension direction, the maximum width of the lens plane in the fourth extension direction, and the maximum thickness of the plano-convex lens are 44mm, 34mm, and 19mm, respectively, and enlarged by a factor of X; where X is in the range of 0.9-1.1. Here, X times is collectively referred to as "enlargement". In practice, if it is less than 1 times, it is reduced; if it is equal to 1 times, it remains unchanged; if it is greater than 1 times, it is enlarged.

[0318] In one specific embodiment, such as Figure 22AAs shown, the maximum length L_1 of the lens plane 231 in the third extension direction is 44 mm, the maximum length of the light-emitting area in the first extension direction is 13.6 mm, and the maximum thickness L_5 of the plano-convex lens is 19 mm; the ratio of the maximum length L_1 of the lens plane 231 in the third extension direction to the maximum length of the light-emitting area in the first extension direction is 3.3 (44 mm / 13.6 mm); the maximum width L_3 of the lens plane 231 in the fourth extension direction is 34 mm, the maximum width of the light-emitting area in the second extension direction is 9 mm, and the ratio of the maximum width L_3 of the lens plane 231 in the fourth extension direction to the maximum width of the light-emitting area in the second extension direction is 3.8 (34 mm / 9 mm). In this embodiment, the values ​​of L_1, L_3, and L_5 can be proportionally reduced or enlarged by up to 10%, and the resulting plano-convex lens can also meet the design requirements. In this embodiment, optionally, the distance D_1 between the light-emitting area and the lens plane 231 is in the range of 1.5mm-4mm; preferably, D_1 is in the range of 2mm-2.5mm; more preferably, D_1 is 2mm. In this embodiment, optionally, the maximum length L_2 of the lens base 233 in the third extension direction is 48mm; the maximum width L_4 of the lens base 233 in the fourth extension direction is 36mm; and the thickness L_6 of the lens base 233 is 2mm. The radius R of the arc of the four rounded corners of the rectangular outline of the lens base 233 is 12.5mm±1mm. By adopting the above dimensional data, better results can be obtained in many aspects such as the collimation of the light irradiated to the display area of ​​the display panel, light energy utilization, and imaging uniformity.

[0319] In another specific embodiment, such as Figure 22B As shown, the maximum length L_1 of the lens plane 231 in the third extension direction is in the range of 36.5mm-37.3mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is in the range of 28.5mm-29.3mm, and the maximum thickness L_5 of the plano-convex lens is in the range of 14.9mm-15.7mm. In this way, the projected image can obtain better brightness and uniformity.

[0320] In another specific embodiment, such as Figure 22BAs shown, the maximum length L_1 of the lens plane 231 in the third extension direction is 36.9 mm, the maximum width L_3 of the lens plane 231 in the fourth extension direction is 28.9 mm, and the maximum thickness L_5 of the plano-convex lens is 15.3 mm. The values ​​of L_1, L_3, and L_5 can be proportionally reduced or enlarged by up to 10%, and the resulting plano-convex lens can also meet the design requirements. Optionally, the maximum length of the plano-convex lens plane in the third extension direction, the maximum width of the lens plane in the fourth extension direction, and the maximum thickness of the plano-convex lens are 36.9 mm, 28.9 mm, and 15.3 mm, respectively, and are enlarged by a factor of X; where X is in the range of 0.9-1.1. Here, X times is collectively referred to as "enlargement." In practice, if it is less than 1 times, it is reduced; if it is equal to 1 times, it remains unchanged; if it is greater than 1 times, it is enlarged.

[0321] In another specific embodiment, such as Figure 22B As shown, the maximum length L_1 of the lens plane 231 in the third extension direction is 36.9 mm; the maximum width L_3 of the lens plane 231 in the fourth extension direction is 28.9 mm; the maximum thickness L_5 of the plano-convex lens is 15.3 mm; and the ratio of the maximum length L_1 of the lens plane 231 in the third extension direction to the maximum length of the light-emitting area in the first extension direction is 2.7 (36.9 mm / 13.6 mm); the maximum width L_3 of the lens plane 231 in the fourth extension direction is 28.9 mm, the maximum width of the light-emitting area in the second extension direction is 9 mm, and the ratio of the maximum width L_3 of the lens plane 231 in the fourth extension direction to the maximum width of the light-emitting area in the second extension direction is 3.2 (28.9 mm / 9 mm). In this embodiment, the values ​​of L_1, L_3, and L_5 can be proportionally reduced or enlarged by up to 10%, and the resulting plano-convex lens can also meet the design requirements. In this embodiment, optionally, the distance D_1 between the light-emitting area and the lens plane 231 is in the range of 1.5mm-4mm; preferably, D_1 is in the range of 2mm-2.5mm; more preferably, D_1 is 2.5mm. In this embodiment, optionally, the maximum length L_2 of the lens base 233 in the third extension direction is 48mm; the maximum width L_4 of the lens base 233 in the fourth extension direction is 35.7mm; and the thickness L_6 of the lens base 233 is 1.7mm. The radius R of the arc of the four rounded corners of the rectangular outline of the lens base 233 is 12.5mm±1mm. By adopting the above dimensional data, better results can be obtained in many aspects such as the collimation of the light irradiated to the display area of ​​the display panel, light energy utilization, and imaging uniformity.

[0322] In some alternative embodiments, such as Figure 21AAs shown, the projection device also includes a second lens LNS2, which is disposed on the display panel (e.g., Figure 24A The second lens LNS2, located between the light-emitting element 21 and the display panel PNL, is positioned away from the light-emitting side of the projection device and is used to collimate the received light. The second lens LNS2, located between the light-emitting element 21 and the display panel PNL, means that during projection, the light from the light-emitting element 21 first passes through the second lens LNS2 and then through the display panel PNL. The optical path (S1+S2) from the center of the convex surface 232 of the plano-convex lens to the center of the light-emitting surface of the second lens LNS2 is in the range of 50mm to 70mm. This optical path should not be too large, otherwise the projection device will be too large, failing to meet the requirements for portability and space utilization; it should also not be too small, otherwise the corresponding components along the optical path will interfere with each other. Therefore, by setting the optical path within this range, the aforementioned defects can be avoided. For example, the second lens LNS2 is a Fresnel lens, with its textured surface located on the light-emitting surface.

[0323] In some optional embodiments, the outer contour of the second lens LNS2 is rectangular. Optionally, the length of the second lens LNS2 is greater than the length of the display area of ​​the display panel, and the difference between the length of the second lens LNS2 and the length of the display area of ​​the display panel does not exceed 20mm, preferably within the range of 5mm-20mm; the width of the second lens LNS2 is greater than the width of the display area of ​​the display panel PNL, and the difference between the width of the second lens LNS2 and the width of the display area of ​​the display panel PNL does not exceed 20mm, preferably within the range of 5mm-20mm. This facilitates fixing while ensuring the optical effect of the lens LNS2.

[0324] In some optional embodiments, the maximum length of the second lens LNS2 is in the range of 98mm to 112mm; the maximum width of the second lens LNS2 is in the range of 55mm to 66mm. The above-mentioned outline dimensions of the second lens LNS2 can match the outline dimensions of the display area, especially suitable for display panel PNL display areas with a diagonal of 4.45 inches, and also suitable for display panel display areas with a diagonal of 4.0 inches to 4.45 inches; for example, the second lens LNS2 is rectangular in the display panel display area. For example, the focal length of the second lens LNS2 is in the range of 80mm to 110mm, thus balancing the uniformity and brightness of the projected image. Preferably, the focal length of the second lens LNS2 is in the range of 88mm to 102mm, for example, 90mm, 95mm, or 100mm.

[0325] In some optional embodiments, the length direction of the second lens LNS2 is parallel to the length direction of the display area of ​​the display panel, and the width direction of the second lens LNS2 is parallel to the width direction of the display area of ​​the display panel. In some optional embodiments, the length direction of the second lens LNS2 is parallel to the length direction of the display area of ​​the display panel, and the width direction of the second lens LNS2 forms a certain angle with the width direction of the display area of ​​the display panel, for example, an angle not exceeding 10°, such as 5°.

[0326] In some alternative embodiments, the width direction of the second lens LNS2 is parallel to the width direction of the display area of ​​the display panel, and the length direction of the second lens LNS2 has a certain angle with the length direction of the display area of ​​the display panel, for example, an angle not exceeding 10°, such as 5°.

[0327] In some alternative embodiments, such as Figure 21A As shown, the projection device also includes a second reflector MR2, which is disposed between the condenser lens 23 and the second lens LNS2, and the light-incident surface of the second reflector LNS2 forms an angle with the lens plane 231. The second reflector is used to reflect the light emitted from the light-emitting element 21 into the display panel PNL. Specifically, the light emitted from the light-emitting element 21 is first converged by the condenser lens 23 and then directed towards the second reflector MR2. It is then reflected by the second reflector MR2 and illuminates the second lens LNS2. After collimation by the second lens LNS2, the light is directed towards the display panel PNL. Optionally, the angle O1 between the light-incident surface of the second reflector LNS2 and the plane perpendicular to the lens plane 231 can be 49°. Further optionally, the angle O2 between the light-incident surface of the second reflector MR2 and the light-incident surface of the second lens LNS2 can be 41°.

[0328] In some alternative embodiments, such as Figure 21AAs shown, the projection device also includes a light-transmitting section GLS, which is disposed between the display panel PNL and the second lens LNS2. There is a gap between the light-transmitting section GLS and the display panel PNL. The material of the light-transmitting section GLS is, for example, glass; the material of the light-transmitting section GLS can, for example, serve as heat insulation. Optionally, both sides of the light-transmitting section GLS are flat, so that light passing through the light-transmitting section GLS will not converge or diverge; it is understood that the light-transmitting section GLS does not function as an optical lens. For example, a first polarizing element POL1 is attached to one side of the light-transmitting section GLS. The first polarizing element POL1 can be a polarizer, such as an absorption polarizer. The first polarizing element POL1 can also be an APF polarizer. In this case, the first polarizing element POL1 is attached to one side of the light-incident surface of the light-transmitting section GLS. For example, the side of the display panel PNL away from the first polarizing element POL1 also includes a second polarizing element POL2, and the absorption axis of the first polarizing element POL1 and the absorption axis of the second polarizing element POL2 form a 90° angle.

[0329] In some optional embodiments, the outer contour of the light-transmitting portion GLS is rectangular; the length of the light-transmitting portion GLS is greater than the length of the display area of ​​the display panel, and the difference between the length of the light-transmitting portion GLS and the length of the display area of ​​the display panel does not exceed 20mm, preferably within the range of 5mm-20mm; the width of the light-transmitting portion GLS is greater than the width of the display area of ​​the display panel, and the difference between the width of the light-transmitting portion GLS and the width of the display area of ​​the display panel does not exceed 20mm, preferably within the range of 5mm-20mm. This ensures that the light-transmitting portion GLS is easy to fix without affecting the optical effect.

[0330] In some optional embodiments, the maximum length of the light-transmitting portion GLS is in the range of 98mm to 112mm; the maximum width of the light-transmitting portion GLS is in the range of 55mm to 66mm. The aforementioned outline dimensions of the light-transmitting portion GLS can be matched with the outline dimensions of the display area, and are particularly suitable for display panel PNL display areas with a diagonal of 4.45 inches, as well as display panel display areas with a diagonal of 4.0 inches to 4.45 inches; for example, the second lens LNS2 is rectangular, and the display panel display area...

[0331] In some optional embodiments, the length direction of the light-transmitting portion GLS is parallel to the length direction of the display area of ​​the display panel, and the width direction of the light-transmitting portion GLS is parallel to the width direction of the display area of ​​the display panel. In some optional embodiments, the length direction of the light-transmitting portion GLS is parallel to the length direction of the display area of ​​the display panel, and the width direction of the light-transmitting portion GLS has a certain angle with the width direction of the display area of ​​the display panel, for example, an angle not exceeding 10°, such as 5°.

[0332] In some alternative embodiments, the width direction of the light-transmitting portion GLS is parallel to the width direction of the display area of ​​the display panel, and the length direction of the light-transmitting portion GLS has a certain angle with the length direction of the display area of ​​the display panel, for example, an angle not exceeding 10°, such as 5°.

[0333] In some alternative embodiments, the light-transmitting portion GLS is arranged parallel to the second lens LNS2.

[0334] In some optional embodiments, the shape of the light-transmitting portion GLS and the shape of the second lens LNS2 can both be the same as the shape of the display panel PNL, for example, both being rectangular. The size of the light-transmitting portion GLS can be the same as the size of the second lens LNS2.

[0335] The imaging optical path of the projection device provided in the embodiments of this disclosure is simulated below to obtain the following results: Figure 24A The optical path simulation diagram shown, and as follows Figure 24B The diagram shows a simulated illuminance reading of the display panel's display area. The simulated illuminance data is shown in Table 1 below, and the brightness and its uniformity are shown in Table 2 below. Table 1 represents the illuminance sampling values ​​at various locations within the 60-inch projection screen, and the positions in the table correspond to the positions of different areas of the projection screen.

[0336] Table 1. Illuminance data for different positions on the display panel.

[0337] 194 270 192 221 315 217 203 280 200 102 110

[0338] Table 2. Brightness and uniformity data of different positions in the display area of ​​the display panel.

[0339] Uniformity 62.65％ A 52.49％ B 52.96％ C 50.10％ D 54.83％

[0340] Table 1 shows the illuminance at the four corners (positions A, B, C, and D) of a 60-inch projection screen, with the remaining data representing the illuminance at the center of each of the 3×3 rectangles of equal area. Table 1 shows that the illuminance at the four corners of the display area is roughly equal, while the illuminance uniformity at different locations in the central area is good. Table 2 shows that the brightness uniformity of the display area reaches 62.65%. Specifically, the nine values ​​in the central area of ​​the display area in Table 1 are P1 to P3, P4 to P6, and P7 to P9, arranged from left to right and top to bottom. The brightness uniformity of the display area is equal to the average of P1, P3, P7, and P9 divided by P5 as a percentage. The brightness uniformity at the four corners (positions A, B, C, and D) of the display area is roughly equal. Furthermore, the collimation of the light illuminating the display area of ​​the display panel can reach within ±8°. Therefore, the projection device provided in this embodiment, by ensuring that the first aspect ratio is greater than or equal to the aspect ratio of the display area of ​​the display panel, helps to improve light energy utilization. Based on this, by using a condenser lens to focus or shape the light emitted by the light-emitting element 21, the light illuminating the display area of ​​the display panel can be made more collimated and uniform, thereby improving image uniformity.

[0341] It should be noted that, in practical applications, the process requirements for the condenser lens 23 include, but are not limited to: a surface roughness better than Ra0.8; both the lens plane 231 and the lens convex surface 232 of the condenser lens 23 are coated with an anti-reflection film, the thickness of which is greater than or equal to 420 nm and less than or equal to 680 nm; and the dimensional tolerance of the condenser lens 23 is ±0.3 mm. The material of the condenser lens 23 includes borosilicate glass (such as H-PZ33) or a material with a refractive index of approximately 1.47. The forming process of the condenser lens 23 includes molding, polishing, coating, and polishing steps.

[0342] It should be noted that the specific outline dimensions of the plano-convex lens provided in this embodiment are not limited to the outline dimensions in the above embodiments. In practical applications, the outline dimensions of the plano-convex lens can be scaled proportionally (90% to 110%) according to specific needs, and the same optical effect can be achieved.

[0343] Figure 25 This is a schematic diagram of a second reflector in a projection device according to some exemplary embodiments of the present disclosure, such as... Figure 25 As shown, the second reflector includes a full-surface mirror reflection area. When light shines on the edge area of ​​the second reflector MR2 near the light source assembly 2 (circled area in the figure), its optical path diagram is as follows. Figure 26 As shown, the light rays are reflected back to the focusing lens by the mirror and converge to a small area. Figure 26 (The area circled by the small and medium circles). In a small area where light converges, high temperatures can easily be generated, burning other devices in that area.

[0344] To prevent light from being reflected back into the plano-convex lens 23 and causing light convergence that could burn the converging area, in some embodiments, the second reflector MR2 can be narrowed, with the structure as follows: Figure 27 As shown, it is similar to Figure 25 The shape shown is the same, except that it is narrowed at one end near the light source component 2. In this way, the light source reflector MR2 will not reflect light from that part, and its optical path diagram is as follows. Figure 28 As shown. However, light will directly shine on the narrowed area, such as housing 1 and / or the second fan 7, and it is necessary to prevent the temperature of the irradiated part from rising, which can easily lead to aging and affect its service life. To this end, a heat-conducting structure, such as a metal film or heat sink fins, can be provided in at least part of the irradiated area to quickly conduct heat away and prevent heat accumulation.

[0345] This disclosure provides an optical path diagram for a second reflector MR2 in a projection device, which can be referenced. Figure 29 The light emitted by the light-emitting element 21 passes sequentially through a condenser lens, a second reflector MR2, a display panel MR2, and a projection lens 3 before exiting. The second reflector MR2 includes a specular reflection area A and a non-spectral reflection area B; the non-spectral reflection area B is configured to prevent the light emitted from the condenser lens from generating reflected light in the non-spectral area A that could re-enter the condenser lens. (Reference) Figure 30 The light emitted by the light source component 2 can undergo specular reflection in the specular reflection area A, and the reflected light can directly enter the display panel PNL for display. The light emitted by the light source component 2 cannot form specular reflection in the non-spectral reflection area B, and it is difficult to reflect it back to the condensing lens to form light convergence, thus solving the problem of device burn-in.

[0346] For example, the size of the specular reflection area A is designed so that light emitted from the condenser lens will not be specularly reflected and re-enter the condenser lens after passing through the specular reflection area A. Alternatively, the size of the specular reflection area A is designed so that light emitted from the condenser lens will not converge after passing through the specular reflection area A and entering the condenser lens, or the impact of light convergence on the reliability of the projection device is acceptable.

[0347] The specular reflection region A can be understood as the region that can achieve the specular reflection function, including the reflective film, such as a high-reflection film.

[0348] This disclosure does not limit the material of the reflective film, as long as it can achieve the reflective function. For example, it can be a metal reflective film, a fully dielectric reflective film, or a metal-dielectric reflective film. Specifically, the reflective film can be an aluminum thin film or a silver thin film, for example, an aluminum thin film or a silver thin film can be prepared on glass using a metal coating process.

[0349] In some embodiments, the non-mirror region B includes a light-absorbing region, where light emitted from the light source 2 is at least partially absorbed, making it difficult to reflect back to the condenser lens and converge the light. For example, the light-absorbing region can be formed with black ink on the mirror surface of the second reflector MR2 to absorb light. For example, the light-absorbing region can include a thermally conductive material, such as metals like copper or aluminum; for example, the light-absorbing region can be made in the form of heat dissipation fins, so that heat can be quickly transferred; for example, the side of the light-absorbing region facing the light-emitting element 21 can be matte, so that unabsorbed light does not form a specular reflection.

[0350] In some embodiments, the non-mirror area B includes a diffuse reflection area. The light emitted by the light source 2 can be diffusely reflected in the diffuse reflection area. The reflection angle of this part of the light is uncertain. On the one hand, the effect of diffuse reflection on the display effect is negligible. On the other hand, the light after diffuse reflection will not be re-converged by the focusing lens. Furthermore, the diffuse reflection area will not generate significant heat focusing due to light irradiation, thus solving the reliability problem caused by the aging of local irradiation devices.

[0351] It should be noted that the diffuse reflection zone can diffusely reflect all the illumination light, or it can diffusely reflect only a portion of the light that falls on it. When the diffuse reflection zone diffusely reflects only a portion of the light that falls on it, some of the light can be absorbed by the diffuse reflection zone. In this way, the influence of the illumination light can be reduced to an acceptable range, ensuring the reliability of the projection device.

[0352] Specifically, the non-mirror reflection area B of the second reflector MR2 can diffusely reflect ineffective light, preventing it from directly hitting the housing 1 and / or the second fan 7, thus avoiding overheating and aging caused by direct light. Simultaneously, the light diffusely reflected by the non-mirror area B will not converge again, preventing the high temperatures that could burn the converged area. Therefore, the performance of the projection device can be improved, and its lifespan extended.

[0353] In some embodiments, there is no step difference between the reflective surface of the specular reflection region A and the surface of the non-spectral reflection region B near the condenser lens.

[0354] In some embodiments, the specular reflection region includes a reflective film and a smooth substrate. For example, the reflective film is closer to the focusing lens than the smooth substrate. For example, the reflective film can be applied to the smooth substrate, and light is reflected onto the reflective film to produce specular reflection. For example, the reflective film can be made of a thin metal film. For example, the reflective film can be an aluminum film or a silver film, etc., and can be prepared onto the smooth substrate using a metal deposition process. The smooth substrate is, for example, smooth glass. For example, the smooth substrate is transparent.

[0355] In some embodiments, the diffuse reflection region includes a reflective film and a roughened substrate. For example, the roughened substrate is frosted glass. For example, the roughened substrate is transparent.

[0356] For example, the reflective film is closer to the condenser lens than the rough substrate. For example, the rough surface of the rough substrate is positioned opposite the reflective film, and the reflective film is tightly bonded to the rough substrate. The surface of the reflective film facing the condenser lens therefore also has a rough morphology, which can produce diffuse reflection of light. For example, the reflective film can be an aluminum thin film or a silver thin film, and can be fabricated on the rough substrate using a metal deposition process. In terms of fabrication, the rough substrate can be formed by roughening a smooth substrate (e.g., sandblasting or grinding), and then simultaneously applying the reflective film to both the smooth and rough substrates in a single process (e.g., using a deposition process).

[0357] In some embodiments, the second reflector MR2 includes a substrate and a reflective film located on the substrate near the condenser lens. The reflective film covers a portion of the substrate area, wherein the area covered by the reflective film is a specular reflection area A; and the area not covered by the reflective film includes a non-spectral reflection area B. For example, the reflective film can be bonded to the reflector MR2. For example, the side of the substrate near the reflective film has a smooth surface, which facilitates the bonding of the reflective film. For example, the side of the substrate away from the reflective film has a rough surface. The area with a rough surface and not covered by the reflective film forms a diffuse reflection area. For example, the entire surface of the substrate away from the reflective film has a rough surface, which simplifies the process. For example, the substrate is a transparent substrate.

[0358] For example, a rough surface can be provided on the side of the substrate facing the condenser lens. For example, the rough surface and the reflective film are both located on the same side of the substrate, so that the area covered by the reflective film is the specular reflection area A, and the substrate area not covered by the reflective film and having a rough surface is the non-spectral reflection area B. For example, the reflective film can be bonded to the surface of the substrate facing the condenser lens; for example, the bonded areas are all smooth surfaces.

[0359] In some embodiments, a rough surface may be disposed on the side of the substrate facing the condenser lens, where a portion of the surface is rough and a portion is smooth. A reflective film is disposed on the side of the substrate away from the condenser lens. For example, the reflective film may be made of a metal thin film. For example, the reflective film may be an aluminum thin film or a silver thin film, and may be fabricated using a metal deposition process. For example, if the side of the substrate away from the condenser lens is entirely smooth, then on the side of the substrate facing the condenser lens, the area corresponding to the rough surface is a diffuse reflection area, and the area corresponding to the smooth surface is a specular reflection area A.

[0360] In some embodiments, reference Figure 29 and Figure 30 The center of the non-mirror reflection region B is closer to the light-emitting element than the center of the mirror reflection region A. For example, the mirror reflection region A and the non-mirror reflection region B divide the second reflector MR2 into "one side and the other side" (e.g., Figure 29 The diagram shows two areas (the upper and lower sides). Generally speaking, the non-mirror reflection area B is closer to the light-emitting element than the mirror reflection area A. As a result, light passing through the non-mirror reflection area B is less likely to be reflected back to the condensing lens to converge, thus solving the problem of device burn-in.

[0361] In some embodiments, reference Figure 29 The outline of the non-mirror region B can be a strip shape. For example, the outline of the non-mirror region B can be a trapezoid. In practical applications, the outline of the non-mirror region B can be set to an isosceles trapezoid. For example, the outline of the non-mirror region B can be a long strip trapezoid.

[0362] In some embodiments, reference Figure 29 The width P1 of the non-mirror reflection region B is in the range of 13-18mm. For example, the width P1 of the non-mirror reflection region B is in the range of 14.5-15.5mm. In this way, the non-mirror reflection region B can be guaranteed to have a large area, effectively eliminating the impact of the condenser lens on the reconvergence of reflected light on the reliability of the projection device, while also satisfying the compact layout of the components inside the projection device.

[0363] In some embodiments, the condensing lens includes a plano-convex lens 23, which has a lens plane and a lens convex surface that are opposite to each other. The lens plane is opposite to the light-emitting side of the light-emitting element 21 and is spaced apart. The lens plane can be positioned opposite to the light-emitting side of the light-emitting element 21, thus converging the light emitted by the light-emitting element 21, achieving light focusing or shaping, ensuring the utilization rate of the light emitted by the light-emitting element 21, and saving energy. For example, the plano-convex lens 23 is the condensing lens. For example, the condensing lens also includes a lens base located on the side of the plano-convex lens closer to the light-emitting element 21, which is in contact with the plano-convex lens to achieve installation and fixation of the plano-convex lens.

[0364] In some embodiments, such as Figure 29 As shown, the outer contour of the second reflector MR2 is trapezoidal, with the upper base of the trapezoid closer to the light-emitting element 21 than the lower base of the other two trapezoids; for example, the non-mirror reflection area B is located on one side of the upper base of the trapezoid. In this way, the second reflector MR2 can effectively reflect imaging light while further reducing its size, thereby improving the compactness of the projection device design.

[0365] Following the design concept described above, the outline of the specular reflection area A of the second reflector MR2 can also be trapezoidal; for example, the non-spectral reflection area B is located on the side where the upper base of the specular reflection area is far from the lower base of the specular reflection area A. The shape of the non-spectral reflection area B can be either trapezoidal or rectangular.

[0366] In practical applications, the shape of the mirror reflection area A can be an isosceles trapezoid.

[0367] In some embodiments, the angle between the extension plane of the second lens LNS2 and the reflecting surface of the second mirror MR2 is in the range of 34° to 48°, thus improving the compactness of the projection device. The plane containing the second lens LNS2 can be understood as a plane passing through the optical center of the second lens and perpendicular to the optical axis of the second lens. When the second lens LNS2 is a Fresnel lens, the plane containing the second lens LNS2 is parallel to the extension plane of the second lens LNS2.

[0368] In some embodiments, the ratio of the lower base length P3 to the upper base length P2 of the specular reflection area A is in the range of 1.4 to 1.8; the angle ξ1 between the upper base of the specular reflection area A and one of the waists is in the range of 98° to 113°, thus the projection device has better compactness.

[0369] In some embodiments, the lower base length P3 of the specular reflection area A is in the range of 105–115 mm, the upper base length P2 is in the range of 61.8–78.6 mm, and the height P4 is in the range of 59.8–75.3 mm. This results in a more compact projection device. It should be noted that…

[0370] In one specific embodiment, the angle between the extension plane of the second lens LNS2 and the reflecting surface of the second mirror MR2 is 41°. The specular reflection area A of the second mirror MR2 is an isosceles trapezoid. The ratio of the length of the lower base P3 to the length of the upper base P2 of the specular reflection area A of the second mirror MR2 is in the range of 1.4-1.8. The angle ξ1 between the upper base and one of the legs of the specular reflection area A of the second mirror MR2 is in the range of 105°-111°. For example, the length of the lower base P3 of the specular reflection area A of the second mirror MR2 is in the range of 110.8±3mm, the length of the upper base P2 is in the range of 67.8±3mm, and the height P4 is in the range of 63.8±3mm. Preferably, the length of the lower base P3 of the specular reflection area A of the second mirror MR2 is in the range of 110.8±0.3mm, the length of the upper base P2 is in the range of 67.8±0.3mm, and the height P4 is in the range of 63.8±0.3mm.

[0371] The width P1 of the non-specular reflection area A is in the range of 13-18 mm, and for example, the width P1 of the non-specular reflection area B is in the range of 14.5-15.5 mm. In this way, the projection device has a better compactness.

[0372] In some embodiments, the display device further includes a first reflector MR1, which is configured to reflect light emitted from the display panel PNL into the projection lens 3. Specifically, the first reflector MR1 is disposed on the side of the display panel PNL away from the light source assembly 2, and the first lens LNS1 is disposed on the side of the first lens LNS1 away from the light source assembly 2. The first reflector MR1 can be a plane mirror. The first reflector MR1 can reflect the light emitted from the display panel PNL into the projection lens 3.

[0373] Figure 31 This is a schematic diagram of a first reflector in a projection device according to some exemplary embodiments of this disclosure. (See reference) Figure 31 The width of the first reflector MR1 decreases as it approaches the display panel PNL, and increases as it moves further away from the display panel PNL. For example, the outer contour of the first reflector MR1 is trapezoidal.

[0374] For example, the first reflector MR1 includes an imaging mirror reflection region C, the outline of which can be trapezoidal. For example, the outline of the imaging mirror reflection region C is the same as that of the second reflector MR2. For example, the outline of the imaging mirror reflection region C can be an isosceles trapezoid.

[0375] In one specific embodiment, the angle between the extended plane of the display panel PNL and the reflective surface of the first reflector MR1 is 45°; the first reflector MR1 is an isosceles trapezoid, and the angle ξ2 between the upper base and one of the legs of the first reflector MR1 is in the range of 98° to 100°. For example, the length of the lower base P6 of the first reflector MR1 is in the range of 110.8±3mm, the length of the upper base P5 is in the range of 81.0±3mm, and the height P7 is in the range of 99.0±3mm. Alternatively, the length of the lower base P6 of the first reflector MR1 is in the range of 110.8±0.3mm, the length of the upper base P5 is in the range of 81.0±0.3mm, and the height P7 is in the range of 99.0±0.3mm. This results in a more compact projection device.

[0376] It should be understood that although some exemplary embodiments of this disclosure have been described and illustrated herein, various other means and / or structures for performing the functions described herein and / or obtaining the results and / or one or more advantages described herein will readily conceive of by those skilled in the art, and each of these variations and / or modifications is considered to be within the scope of embodiments of this disclosure. More generally, those skilled in the art will readily understand that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications using the teachings of this disclosure. Those skilled in the art will recognize or be able to ascertain many equivalents of the specific utility model embodiments described herein using no more than conventional experimentation. Therefore, it should be understood that the foregoing embodiments are presented by way of example only, and that utility model embodiments may be practiced in ways different from the specific descriptions and claims within the scope of the appended claims and their equivalents. The utility model embodiments relate to each individual feature, system, article, material, kit, and / or method described herein. Furthermore, any combination of two or more such features, systems, articles, materials, kits and / or methods is included within the scope of this invention if such features, systems, articles, materials, kits and / or methods are not inconsistent with each other.

[0377] Unless otherwise specified, all technical and scientific terms used in this disclosure shall have the same meaning as commonly understood by one skilled in the art to which this disclosure pertains.

[0378] As used herein in the specification and claims, the phrase “and / or” should be understood to mean “any one or both” of the elements so combined, i.e., elements that are present in combination in some cases and not in combination in others. The elements listed with “and / or” should be interpreted in the same way, i.e., “one or more” of the elements so combined. In addition to the elements specifically identified by the “and / or” clause, other elements may optionally be present, whether related to or unrelated to those specifically identified. Thus, as a non-limiting example, when used in conjunction with open-ended language such as “comprising,” a reference to “A and / or B” may, in one embodiment, refer only to A (optionally including elements other than B); in another embodiment, only to B (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements), and so on.

[0379] Those skilled in the art will understand the term "substantially" as used herein (such as in "substantially all light" or "substantially composed of"). The term "substantially" may also include embodiments having "entirely," "completely," "all," etc. Thus, in embodiments, the adjective "substantially" is also removable. Where applicable, the term "substantially" may also refer to 90% or higher, such as 95% or higher, particularly 99% or higher, even more particularly 99.5% or higher, including 100%. The term "comprising" also includes embodiments in which the term "comprising" means "composed of." The term "and / or" specifically refers to one or more items mentioned before and after "and / or." For example, the phrase "item 1 and / or item 2" and similar phrases may refer to one or more of item 1 and item 2. The term "comprising" may mean "composed of" in one embodiment, but may also mean "containing at least the defined class and optionally containing one or more other classes" in another embodiment.

[0380] Furthermore, the terms first, second, third, etc., used in this specification and claims are used to distinguish between similar elements and do not indicate any order, quantity, or importance. It should be understood that the terms thus used are interchangeable where appropriate, and the embodiments of this disclosure described herein can be operated in a different order than that described or shown herein.

[0381] It should be noted that the embodiments mentioned above are illustrative and not limiting of this disclosure, and those skilled in the art will be able to devise many alternative embodiments without departing from the scope of the appended claims. Any reference marks placed between parentheses in the claims should not be construed as limiting the claims. The use of the verb “comprising” and its variations does not exclude the presence of elements or steps different from those stated in the claims. The wording “a” or “an” in the claims of this disclosure does not exclude a plurality; it is merely for convenience of narration and should not be construed as limiting the scope of this disclosure.

[0382] This disclosure can be implemented by means of hardware comprising several different elements, and by means of a suitably programmed computer. In the apparatus claims enumerating several devices, several of these devices may be embodied by the same hardware item. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that combinations of these measures cannot be advantageously used.

[0383] This disclosure is further applicable to apparatuses that include one or more of the characterizing features described in this specification and / or shown in the accompanying drawings. This disclosure further relates to methods or processes that include one or more of the characterizing features described in this specification and / or shown in the accompanying drawings.

[0384] The various aspects discussed in this disclosure can be combined to provide additional advantages. Furthermore, those skilled in the art will understand that embodiments can be combined, and more than two embodiments can be combined. Additionally, some features can form the basis of one or more divisional applications.

Claims

1. A projection device, comprising: The projection device comprises a housing, a light source assembly, and a projection lens, characterized in that an accommodating space is formed inside the projection device, and the projection device further comprises: a second reflector, a second fan, and a lens assembly located within the accommodating space; the second reflector is disposed on the light-emitting side of the light source assembly and is used to reflect the light emitted by the light source assembly into the lens assembly, and the lens assembly is used to collimate the light; The containment space includes an airflow space, which includes a first subspace and a second subspace. The first subspace is defined by the light source assembly, the second reflector, the lens assembly, and a portion of the housing, and the second subspace is located around the first subspace. The second fan is used to drive the internal air circulation within the airflow space, so that the internal air circulates between the first subspace and the second subspace; The second fan includes a fan housing, which includes a functional area and a non-functional area. The functional area is provided with a second air inlet and a second air outlet, and the non-functional area is provided with a ventilation section that penetrates the fan housing. The second air inlet faces the second subspace, and the second air outlet is configured to simultaneously discharge air into the first subspace and the second subspace; The air discharged into the first subspace enters the second air inlet through the ventilation section; the air discharged into the second subspace flows within the second subspace and then enters the second air inlet.

2. The projection device according to claim 1, characterized in that, The housing also includes a third opening, at least a portion of which is located on the rear surface of the housing; The projection device further includes a first heat sink, which is located at the third opening; The light source assembly, the projection lens, the first heat sink, and the housing together define the accommodating space; The second subspace includes: a first air duct located between the first radiator and the second fan, wherein at least a portion of the first radiator forms one side wall of the first air duct; The air discharged from the second air outlet into the first subspace can pass through the ventilation section and the first air duct in sequence before entering the second air inlet.

3. The projection device according to claim 2, characterized in that, The second air inlet is positioned facing the first air duct.

4. The projection device according to claim 2, characterized in that, The projection device further includes a display panel and a first lens, wherein the display panel is located on the side of the lens assembly away from the second reflector, and the first lens is located on the side of the display panel away from the lens assembly; The lens assembly and the display panel have a second gap, and the first lens and the display panel have a third gap; The second subspace also includes a U-shaped air duct, which includes a second air duct and a third air duct arranged side by side and interconnected. The second air duct includes a second gap, and the third air duct includes the third gap. The airflow path of the second air outlet into the second subspace includes the second air duct, the third air duct, and the first air duct.

5. The projection device according to claim 4, characterized in that, The second air outlet is positioned facing the second air duct. The air discharged from the second air outlet into the second subspace passes through the second air duct, the third air duct, and the first air duct in sequence before entering the second air inlet.

6. The projection device according to any one of claims 2 to 5, characterized in that, Along the direction perpendicular to the reflective surface of the second reflector, the projection of the second reflector onto the fan casing of the second fan does not overlap with at least a portion of the ventilation section.

7. The projection device according to claim 6, characterized in that, The reflective surface of the second mirror is trapezoidal, the trapezoid having a first base and a second base that are parallel to each other, and a waist connecting the first base and the second base. The length of the first base is greater than the length of the second base. The first base is located in the first subspace near the lens assembly, and the second base is located in the second subspace away from the lens assembly. Along the direction perpendicular to the reflective surface of the second reflector, the projection of the waist of the trapezoid on the fan housing is in contact with or adjacent to the ventilation section.

8. The projection device according to claim 7, characterized in that, The ventilation section is distributed on both sides of the second reflector; the ventilation section includes multiple ventilation holes, and each side of the second reflector is provided with multiple ventilation holes.

9. The projection device according to any one of claims 2 to 5, characterized in that, The second air outlet includes a first region and a second region. The second region is the region of the second air outlet that is opposite to the second subspace. The first region is the remaining region of the second air outlet located in the second region on the side closer to the first subspace. The area of ​​the first region is the first effective exhaust area, the area of ​​the second region is the second effective exhaust area, and the ratio of the ventilation area of ​​the ventilation section to the first effective exhaust area is within the range of [1, 1.3].

10. The projection device according to claim 9, characterized in that, The ratio of the ventilation area of ​​the ventilation section to the first effective exhaust area is within the range of [1.1, 1.3].

11. The projection device according to any one of claims 2 to 5, characterized in that, The second air outlet includes a first region and a second region. The second region is the region of the second air outlet that is opposite to the second subspace. The first region is the remaining region of the second air outlet located on the side of the second region closer to the first subspace. The area of ​​the first region is the first effective discharge area, and the area of ​​the second region is the second effective discharge area. The ventilation area of ​​the second air inlet is M times the sum of the first effective exhaust area and the second effective exhaust area, where M is in the range of [1, 1.2].

12. The projection device according to any one of claims 2 to 5, characterized in that, The second air outlet includes a first region and a second region. The second region is the region of the second air outlet that is opposite to the second subspace. The first region is the remaining region of the second air outlet located on the side of the second region closer to the first subspace. The area of ​​the first region is the first effective discharge area, and the area of ​​the second region is the second effective discharge area. The second effective discharge area is (1, 3] times the first effective discharge area.

13. The projection device according to any one of claims 1 to 5, characterized in that, The lens assembly includes a light-transmitting portion and a second lens, wherein the light-transmitting portion is located on the side of the second lens away from the second reflector.

14. The projection device according to any one of claims 2 to 5, characterized in that, The lens assembly is configured to divert the air discharged from the second air outlet, so that a portion of the air discharged from the second air outlet enters the first subspace, and a portion of the air discharged from the second air outlet enters the second subspace.

15. The projection device according to claim 14, characterized in that, The lens assembly includes: a light-transmitting portion and a second lens, wherein the light-transmitting portion is located on the side of the second lens away from the second reflector; The lens assembly further includes: a fixing member connected to the housing, the fixing member being disposed opposite to the second air outlet; The edge of the light-transmitting part near the second air outlet and the edge of the second lens near the second air outlet are both limited by the fixing component.

16. The projection device according to any one of claims 2 to 5, characterized in that, The second air outlet includes a first opening and a second opening, which are arranged side by side, and the length of the first opening is less than the length of the second opening. Wherein, at least a portion of the first opening is configured to discharge air toward the first subspace, and at least a portion of the second opening is configured to discharge air toward the second subspace.

17. The projection device according to any one of claims 1 to 5, characterized in that, The projection device further includes: The first polarizing element is used to convert the light reflected by the second reflector into first polarized light with a first polarization direction; The display panel is located on the side of the lens assembly away from the second reflector; The first lens is located on the side of the display panel away from the lens assembly, or is disposed between the display panel and the first polarizing element; The first reflector is configured to reflect light emitted from the display panel into the projection lens; The second polarizing element is disposed on the side of the display panel away from the first polarizing element, and is used to emit one of the polarized light in the first polarization direction and the polarized light in the second polarization direction from the projection lens, wherein the first polarization direction is perpendicular to the second polarization direction. The first reflector and the second polarizing element may be the same element or different elements; the display panel is a liquid crystal display panel.

Images