A projection device

Abstract

The present disclosure provides a projection device, comprising: a display panel and a projection lens, and a lighting assembly comprising a plurality of lighting sources, the lighting sources entering the display panel and projecting out of the projection lens; wherein the illumination ranges of different lighting sources on the display panel at least partially do not overlap; and the illumination ranges of the plurality of lighting sources on the display panel cover the display area of the display panel.

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 display device that magnifies tiny image information through a lens and projects it onto a screen. It is widely used in people's daily lives, such as teaching, business, media advertising, and home entertainment. Summary of the Invention

[0003] This disclosure provides a projection device, including an illumination assembly, a display panel, and a projection lens.

[0004] The lighting assembly includes: a plurality of lighting sources, which enter the projection lens through the display panel and exit the projection lens;

[0005] Wherein, the illumination areas of different lighting sources on the display panel do not overlap at least partially; and the illumination areas of the plurality of lighting sources on the display panel cover the display area of ​​the display panel.

[0006] In some embodiments, the lighting source includes:

[0007] light source;

[0008] A first collimating lens is disposed on the light-emitting side of the light source and is used to collimate the light rays illuminating the first collimating lens from the light source.

[0009] A lamp cup is located between the light source and the first collimating lens, and is arranged around the optical axis of the first collimating lens to form a cylindrical structure; the cylindrical structure is used to reflect the light from the light source that is irradiated onto the inner surface of the cylindrical structure back to the first collimating lens;

[0010] The cylindrical structure has a first opening facing the first collimating lens and a second opening facing the first collimating lens, wherein the area of ​​the first opening is smaller than the area of ​​the second opening.

[0011] In some embodiments, the first collimating lens includes a Fresnel lens.

[0012] In some embodiments, a slit of a predetermined width exists between the first collimating mirrors of different illumination sources.

[0013] In some embodiments, the axis of the light source is parallel to the axis of the first collimating lens.

[0014] In some embodiments, the lighting source includes:

[0015] light source;

[0016] A lens is disposed on the light-emitting side of the light source; the lens is used to collimate the light rays from the light source that illuminate the inner surface of the lens.

[0017] In some embodiments, the lens includes a freeform lens or an aspherical lens.

[0018] In some embodiments, the optical axis of the illumination source is at an angle to the thickness direction of the display panel, and the angle ranges from 0° to 90°.

[0019] The projection device further includes a second collimating lens, which is disposed on the side of the lens away from the light source, and is used to collimate the light rays from the light source that illuminate the second collimating lens.

[0020] In some embodiments, the second collimating lens includes a Fresnel lens.

[0021] In some embodiments, there is a first intersection point between different optical axes of the different illumination sources; the first intersection point is located on the side of the plurality of illumination sources near the second collimating lens.

[0022] In some embodiments, there is a second intersection point between the optical axis of the illumination source and the second collimating lens;

[0023] The included angle satisfies

[0024] Where d represents the distance between the second intersection point and the optical axis of the second collimating lens; f , This indicates the focal length of the second collimating lens.

[0025] In some embodiments, a plurality of the illumination sources are arranged in an array, and the shape of the illumination area of ​​the plurality of illumination sources on the plane of the display panel is the same as the shape of the display area.

[0026] In some embodiments, the projection device further includes:

[0027] A polarizing assembly is disposed between the light-emitting side of the illumination source and the display panel; it is used to convert the light emitted by the illumination assembly into first polarized light with a first polarization direction; wherein, the display panel is disposed on the side of the polarizing assembly away from the illumination assembly, 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;

[0028] A reflector is disposed on the side of the display panel away from the polarizing component, for reflecting one of the polarized light in the first polarization direction and the polarized light in the second polarization direction to the projection lens.

[0029] In some embodiments, the polarizing component includes:

[0030] A heat-insulating substrate is disposed between the display panel and the lighting source;

[0031] A polarizer is disposed on the surface of the heat insulation substrate near the lighting source; the polarizer is used to convert the light emitted by the lighting source into first polarized light with a first polarization direction.

[0032] In some embodiments, the reflective assembly includes: an analyzer, a field lens, and a reflector;

[0033] The analyzer is located between the display panel and the field lens; the analyzer is used to transmit one of the polarized light in the first polarization direction and the polarized light in the second polarization direction.

[0034] The field lens is positioned between the analyzer and the reflector to focus the light emitted from the analyzer and then emit the focused light to the reflector.

[0035] The reflector is used to reflect the focused light onto the projection lens. Attached Figure Description

[0036] 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:

[0037] Figure 1 This is a schematic diagram of the structure of a projection device provided in an embodiment of this disclosure.

[0038] Figure 2 for Figure 1 A schematic diagram of the light source provided in the embodiment.

[0039] Figure 3 This is an exploded schematic diagram of a single lighting source provided in some embodiments.

[0040] Figure 4 This is a schematic diagram of another projection device provided in an embodiment of this disclosure.

[0041] Figure 5 for Figure 2 A schematic diagram of the illumination source and the second collimating lens provided in the embodiment.

[0042] Figure 6 Intensity distribution diagrams of a single light source provided in some embodiments.

[0043] Figure 7 This is a diagram showing the illumination angle distribution of a single light source provided in some embodiments.

[0044] Figure 8 This is a test point diagram of the projection screen provided in some embodiments.

[0045] Figure 9 This is an intensity distribution diagram of multiple light sources provided in the embodiments of this disclosure.

[0046] Figure 10 This is a diagram showing the illumination angle distribution of multiple light sources provided in the embodiments of this disclosure.

[0047] Figure 11 The diagram shows a comparison of the optical structures of multiple lighting sources and a single lighting source provided in the embodiments of this disclosure. Detailed Implementation

[0048] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0049] In this specification, for convenience, terms such as "middle," "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer" are used to indicate orientation or positional relationships in conjunction with the accompanying drawings. This is solely for the purpose of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this disclosure. The positional relationships of the constituent elements may be appropriately changed depending on the direction in which each constituent element is described. Therefore, the terminology used is not limited to those described in the specification and may be appropriately replaced as appropriate.

[0050] Unless otherwise defined, the technical or scientific terms used in the embodiments of this disclosure should be understood in their ordinary sense by one of ordinary skill in the art to which this disclosure pertains. The terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms "installed," "connected," and "linked" should be interpreted broadly. For example, they may refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or link; a direct connection or an indirect connection via an intermediate component, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0051] In related technologies, single LCD projection systems typically require large illumination spots due to cost and the physical size of the display panel. Furthermore, if telecentric projection lenses are used for imaging, the angle of the illumination spot must be specified to maximize the efficiency of the optical system.

[0052] In some single LCD projection systems, the uniformity of the display is poor because a reflector or plano-convex lens is used in conjunction with a collimating lens to provide illumination to the display panel.

[0053] Figure 1 This is a schematic diagram of the structure of a projection device provided in an embodiment of this disclosure. Figure 2 for Figure 1 The light emission diagram of the illumination source provided in the embodiment is as follows: Figure 1 and Figure 2 As shown, the projection device includes an illumination component 1, a display panel 3, and a projection lens 5. The illumination component 1 includes multiple illumination sources 101, which enter the projection lens 5 through the display panel 3 and exit from the projection lens 5. The illumination areas of the different illumination sources 101 on the display panel 3 do not overlap at least partially (i.e., the illumination areas of the different illumination sources 101 on the display panel 3 may only partially overlap or not overlap at all), and the illumination areas of the multiple illumination sources 101 on the display panel 3 cover the display area of ​​the display panel 3.

[0054] In this embodiment, the lighting component 1 includes multiple light sources 101, and the illumination areas of the different light sources 101 on the display panel 3 do not overlap at least partially, thus covering the display area of ​​the display panel 3. This arrangement results in multiple small, at least partially non-overlapping light spots in the illumination area of ​​the lighting component 1 on the display panel 3, whereas in related technologies, a lighting component 1 including only one light source 101 only has one large light spot in the illumination area of ​​the display panel 3. Because this large light spot has a large area, its edges appear darker than its center, leading to poor illumination by the light source 101 and consequently, poor projection performance of the projection device. In the embodiments of this disclosure, the illumination area of ​​the display panel 3 illuminated by the illumination component 1 has a plurality of small light spots that are at least partially non-overlapping. Since the area of ​​the small light spots is small, the brightness difference between the edge area and the center area of ​​the small light spots is not significant. Therefore, the uniformity of the light brightness received at each position on the display panel 3 of the projection device provided in the embodiments of this disclosure is higher, thereby improving the projection effect of the projection device.

[0055] Figure 3 This is a schematic diagram of the structure of a single lighting source provided in some embodiments, such as... Figure 3 As shown, in some embodiments, the illumination source 101 includes a light source 100, a first collimating lens 101b, and a lamp cup 101a. The light source 100 may specifically include a lamp panel and a light-emitting element. The lamp panel is fixedly connected to the lamp cup 101a. A reflective layer may also be provided on the lamp panel, wherein the reflective layer and the light-emitting element are located on the same side of the lamp panel facing the lamp cup 101a. The reflective layer helps to improve light utilization, thereby increasing projection brightness.

[0056] It should be noted that the light emitted by the light source 100 in this embodiment can be natural light, and the natural light in this embodiment refers to light that does not exhibit polarization characteristics. Specifically, the natural light emitted by the light source 100 can be white light.

[0057] like Figure 3 As shown, the first collimating lens 101b is disposed on the light-emitting side of the light source 100 and is used to collimate the light rays illuminating the first collimating lens 101b from the light source 100.

[0058] A lamp cup 101a is located between the light source 100 and the first collimating lens 101b, and is arranged around the optical axis 101c of the first collimating lens 101b, forming a cylindrical structure. This cylindrical structure is used to reflect the light from the light source 100 that is incident on the inner surface of the cylindrical structure back to the first collimating lens 101b. The cylindrical structure has a first opening 1010 facing the light source 100 and a second opening 1011 facing the first collimating lens 101b, and the area of ​​the first opening 1010 is smaller than the area of ​​the second opening 1011.

[0059] In the setting where the lamp cup 101a surrounds the optical axis 101c of the first collimating lens 101b, "surrounding" means that the optical axis 101c of the first collimating lens 101b passes through the second opening 1011 and the first opening 1010 of the cylindrical structure in sequence, and the cylindrical structure surrounds the optical axis 101c of the first collimating lens 101b.

[0060] The lamp cup 101a is preferably made of aluminum alloy material that is integrally die-cast, and a reflective medium film layer can be provided on the inner surface of the lamp cup 101a to reduce the energy loss of the lighting source 101.

[0061] In some embodiments, the lamp cups of the plurality of lighting sources 101 can be formed as an integral structure or as multiple independent structures.

[0062] In some embodiments, the first collimating lens 101b includes a Fresnel lens, wherein the use of a Fresnel lens in the first collimating lens 101b can prevent large spherical aberrations and aberrations from appearing at the lens edge, thereby improving the imaging quality.

[0063] In some embodiments, such as Figure 1 As shown, there is a slit H of a preset width between the first collimating mirrors 101b of different lighting sources 101, which is used to facilitate the assembly of their own devices and avoid the spatial limitations of their own device structures.

[0064] The width of the slit H can be set according to actual needs.

[0065] In some embodiments, the axis of the light source 100 is parallel to the axis of the first collimating lens 101b. This arrangement is beneficial for the light emitted by the light source 100 to be directed to the first collimating lens 101b to the maximum extent, thereby improving light utilization and thus improving projection brightness.

[0066] Figure 4 This is a schematic diagram of another projection device provided in an embodiment of this disclosure. Figure 5 for Figure 2 The schematic diagram of the illumination source and the second collimating lens provided in the embodiment is as follows: Figure 4 and Figure 5As shown, in some embodiments, the illumination source 101 includes a light source 100 and a lens 101c. The lens 101c is disposed on the light-emitting side of the light source 100 and is used to collimate the light rays from the light source 100 that illuminate the lens 101c.

[0067] In this embodiment, the light source 100 can be connected to... Figure 1 The light source 100 in the embodiments has the same structure.

[0068] In some embodiments, lens 101c includes a freeform lens or an aspherical lens.

[0069] In some embodiments, such as Figure 5 As shown, the optical axis of the illumination source 101 forms an angle θ with the thickness direction of the display panel 3, where the value of the angle θ ranges from (0° to 90°), thereby saving space in the projection device. For example, the value of the angle θ can be 30°, 45°, 60°, or 85°.

[0070] The projection device also includes a second collimating lens 101d, which is disposed on the side of the lens 101c away from the light source 100, and is used to collimate the light from the light source 100 that is incident on the second collimating lens 101d.

[0071] In some embodiments, the second collimating lens 101d includes a Fresnel lens, wherein the use of a Fresnel lens in the second collimating lens 101d can prevent large spherical aberrations and aberrations at the lens edge, thereby improving the imaging quality.

[0072] In some embodiments, there is a first intersection point E between different optical axes of different illumination sources 101; the first intersection point E is located on the side of the plurality of illumination sources 101 near the second collimating lens 101d.

[0073] like Figure 5 As shown, in some embodiments, there is a second intersection point F between the optical axis of the illumination source 101 and the second collimating lens 101d, such as... Figure 3 As shown, the angle θ between the optical axis of the illumination source 101 and the thickness direction of the display panel 3 satisfies:

[0074] Where d represents the distance between the second intersection point F and the optical axis of the second collimating lens 101d; f , This indicates the focal length of the second collimating lens 101d.

[0075] like Figure 1 and Figure 4As shown, in some embodiments, multiple illumination sources 101 are arranged in an array, and the shape of the illumination area of ​​the multiple illumination sources 101 on the plane of the display panel 3 is the same as the shape of the display area. For example, the shape of the illumination area of ​​the multiple illumination sources 101 on the plane of the display panel 3 is rectangular; or elliptical; or circular; or hexagonal, etc.

[0076] In some embodiments, the shape of the illumination area of ​​the plurality of illumination sources 101 on the plane of the display panel 3 is rectangular, and the length direction of the illumination area is the same as the length direction of the display area, and the width direction of the illumination area is the same as the width direction of the display area. That is, the long side of the illumination area is parallel to the long side of the display area, and the short side of the illumination area is parallel to the short side of the display area. Of course, the illumination area of ​​the illumination source 101 and the display area of ​​the display panel 3 can both be square. In this case, the four sides of the illumination area are parallel to the four sides of the display area.

[0077] The ratio of the length of the irradiated area to the length of the display area is 1:a, and the ratio of the width of the irradiated area to the width of the display area is 1:b. Both a and b are greater than 0, and the ratio of a:b is between 0.8:1 and 1.2:1. This reduces or prevents dark spots from appearing on the display screen. Preferably, a = b, thereby minimizing dark spots and improving the display effect to the greatest extent possible.

[0078] For example, in one example, the size of the illumination area of ​​the illumination source 101 on the plane where the display panel 3 is located is 10mm × 10mm or 16mm × 11mm.

[0079] In some embodiments, such as Figure 1 and Figure 4 As shown, the projection device also includes a polarizing component 2 and a reflecting component 4. The polarizing component 2 is disposed between the light-emitting side of the illumination source 101 and the display panel 3, and is used to convert the light emitted by the illumination component 1 into first polarized light with a first polarization direction. The display panel 3 is disposed on the side of the polarizing component 2 away from the illumination component 1, and is used to adjust the polarization direction of the first polarized light to emit second polarized light.

[0080] 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.

[0081] It should be noted that the display panel 3 may include multiple pixel areas, each of which can adjust the polarization direction of the first polarized light to obtain second polarized light with a polarization direction between the first and second polarization directions. It should also be noted that "between the first and second polarization directions" includes both the first and second polarization directions as a critical direction. That is, the polarization direction of the second polarized light can be the first polarization direction, the second polarization direction, or a direction that lies between the first and second polarization directions and intersects both.

[0082] The display panel 30 can be a liquid crystal display panel, specifically including: an array substrate and a cell substrate disposed opposite to each other, and a liquid crystal layer located between the array substrate and the cell substrate. In one example, the array substrate includes: a first substrate, multiple gate lines and multiple data lines disposed on the first substrate, the multiple gate lines and multiple data lines being intersected to define multiple pixel regions, each pixel region being provided with a pixel electrode. The cell substrate includes: a second substrate and a common electrode disposed on the second substrate. By applying a pixel voltage to the pixel electrode and applying a common electrode to the common electrode, an electric field is generated between the pixel electrode and the common electrode to drive the liquid crystal in the pixel region to deflect, thereby adjusting the polarization direction of the first polarized light.

[0083] It should be noted that the polarization direction of the emitted second polarized light is not necessarily fixed for any given pixel area; the polarization direction of the second polarized light can be different when different images are projected by the projection device. It should also be noted that the specific type of liquid crystal display panel is not limited in this embodiment. For example, it can be a vertical alignment (VA) type or a twisted nematic (TN) type display panel, in which case the common electrode is disposed on the second substrate. Alternatively, it can be an in-planar switching (IPS) type display panel, a fringe field switching (FFS) type display panel, or an advanced super-dimensional switch (ADS) type display panel, in which case the common electrode is disposed on the first substrate, as long as an electric field can be generated between the pixel electrode and the common electrode to drive the liquid crystal deflection.

[0084] The reflector 4 is located on the side of the display panel 3 away from the polarizer 2, and is used to reflect one of the polarized light in the first polarization direction and the polarized light in the second polarization direction to the projection lens 5, thereby realizing projection display.

[0085] The following example uses reflector 4 to reflect polarized light in the second polarization direction. Figure 1 The projection display principle of the projection device shown will be explained.

[0086] The light emitted by the illumination component 1 passes through the polarizing component 2 and becomes first polarized light with a first polarization direction, which then illuminates the display panel 3. When a white screen is required, the voltage of each pixel area in the display panel 3 can be controlled to adjust the polarization direction of the first polarized light by the liquid crystal in each pixel area, generating second polarized light. The second polarized light illuminates the reflector component 4 and is reflected by the reflector component 4 to the projection lens 5, thereby displaying a white screen. When a black screen is required, the voltage of each pixel area in the display panel 3 can be controlled so that the liquid crystal in each pixel area does not change the polarization direction of the first polarized light and still emits first polarized light. Since the first polarized light passes through the reflector component 4, no light is emitted to the projection lens 5, thus displaying a black screen. When a grayscale image (i.e., an image with a brightness lower than a white image but higher than a black image) needs to be displayed, the voltage of each pixel area in the display panel 3 can be controlled to adjust the polarization direction of the first polarized light in each pixel area, generating polarized light with a third polarization direction. This third polarized light then illuminates the reflector 4. The third polarization direction intersects with both the first and second polarization directions, and the polarized light in the third polarization direction can be decomposed into a first component in the first polarization direction and a second component in the second polarization direction. The second component is reflected by the reflector to the projection lens 5, thus displaying the grayscale image.

[0087] Similarly, when the reflector 4 is used to reflect polarized light in the first polarization direction, if a white image is required, the voltage of each pixel area in the display panel 3 is controlled so that the liquid crystal in each pixel area does not change the polarization direction of the first polarized light and still emits polarized light in the first polarization direction. This polarized light in the first polarization direction illuminates the reflector 4 and is reflected by the reflector 4 to the projection lens 5, thereby displaying a white image. If a black image is required, the voltage of each pixel area in the display panel 3 is controlled so that the liquid crystal in each pixel area adjusts the polarization direction of the first polarized light to generate polarized light in the second polarization direction. At this time, no light shines on the projection lens 5, thereby displaying a black image. If a grayscale image is required, the voltage of each pixel area in the display panel 3 is controlled so that the liquid crystal in each pixel area adjusts the polarization direction of the first polarized light to generate polarized light in the third polarization direction. The polarized light in the third polarization direction can be decomposed into a first component in the first polarization direction and a second component in the second polarization direction. The first component is reflected by the reflector 4 to the projection lens 5, thereby displaying a grayscale image.

[0088] In this embodiment, the reflector 4 can be designed to reflect either the second polarized light or the first polarized light emitted from the display panel 3, thereby reflecting light of different brightness to the projection lens 5 and achieving image display of different brightness. It is understood that whether the reflector 4 is designed to reflect the first or second polarized light depends on the specific type of the display panel. For example, when the display type of the display panel 3 is ADS, IPS, VA, or TN (normal white) mode, the reflector 4 can be designed to reflect the second polarized light; when the display type of the display panel 3 is TN (normal black) mode, the reflector 4 can be designed to reflect the first polarized light.

[0089] It is understandable that using the reflection of the reflector 4 to change the direction of light propagation helps to reduce the size of the projection device.

[0090] In some embodiments, the polarizing assembly 2 includes a heat-insulating substrate 2a and a polarizer 2b, with the heat-insulating substrate 2a disposed between the display panel and the lighting source 101. The material of the heat-insulating substrate 2a is preferably a material with high transmittance in the visible light range; for example, the material of the heat-insulating substrate 2a can be H-K9L, BK7, or blue glass.

[0091] Furthermore, an infrared blocking film can be deposited on the light-emitting surface of the heat-insulating substrate 2a to improve the optical stability of the system.

[0092] A polarizer 2b is disposed on the surface of the heat insulation substrate 2a near the illumination source 101, and is used to convert the light emitted by the illumination source 101 into first polarized light with a first polarization direction. Preferably, the polarizer 2b is a reflective polarization device (APF). This polarizer 2b can obtain first polarized light that can be 100% transmitted through the display panel 3 by polarization filtering of the naturally polarized light after alignment.

[0093] In some embodiments, the reflective assembly 4 includes: an analyzer 401, a field lens 402, and a reflector 403. The analyzer 401 is located between the display panel 3 and the field lens 402, and is used to transmit one of polarized light in a first polarization direction and polarized light in a second polarization direction.

[0094] Among them, the analyzer 401 is preferably a reflective polarizing device (thin film), which is used in conjunction with the display panel 3 and can adjust the grayscale of the display screen 3.

[0095] A field lens 402 is positioned between the analyzer 401 and the reflector 403 to focus the light emitted from the analyzer 401 and project the focused light onto the reflector 403. Preferably, the field lens is a Fresnel lens, which can reduce the size of the imaging beam, thereby improving the system's optical efficiency.

[0096] The reflector 403 is used to reflect the focused light to the projection lens 5. The reflector 403 is preferably a coated high-reflectivity plane mirror, which is used to deflect the light path, thereby reducing the system size.

[0097] Figure 6 The following is an intensity distribution diagram of a single light source provided in some embodiments. Figure 7 This is a diagram showing the illumination angle distribution of a single light source provided in some embodiments. Figure 8 This is an intensity distribution diagram of multiple light sources provided in the embodiments of this disclosure. Figure 9 This is a diagram showing the illumination angle distribution of multiple light sources provided in the embodiments of this disclosure, such as... Figures 6 to 9 As shown, taking a projection imaging lens with an F3.0 aperture as an example, when the illumination angle of the light source 100 is 10° in both the horizontal and vertical (H and V) directions, the illumination intensity distribution and illumination angle distribution of the projection device of a single light source 100 are as follows: Figure 6 and Figure 7 As shown. Taking a projection imaging lens with an F3.0 aperture as an example, under the condition of the same light source 100 size, when the illumination angles of multiple light sources 100 are 10° in both the horizontal and vertical (H and V) directions, the illumination intensity distribution and illumination angle distribution of the projection device with multiple light sources 100 are as follows: Figure 8 and Figure 9 As shown.

[0098] Depend on Figures 6 to 9 As shown, the projection uniformity of a projection device with multiple light sources 100 is higher than that of a projection device with a single light source 100.

[0099] Figure 10 This is a test point diagram of the projection screen provided in some embodiments, such as Figure 10 As shown, in Figure 6 and Figure 7 as well as Figure 8 and Figure 9 Thirteen test points were selected on the projection screen formed by the projection device, and their illuminance data were used to evaluate the brightness uniformity of the projected image. Without considering lens vignetting, the uniformity of the illumination spot on the display panel 3 can reflect the uniformity of the projected image in the projection device.

[0100] like Figure 10As shown, in a projection device with a single light source 100, the four corners at the outermost edge of the projected image are represented as corner A, corner B, corner C, and corner D, respectively. Corners A, B, C, and D are used as test points, and their brightness is significantly different from that of the central test point P5. The final image presentation effect is that four dark corners appear at the edge of the screen.

[0101] Among them, the brightness uniformity value of the four test points A, B, C, and D is the ratio of the test brightness of each test point to the test brightness of point P5.

[0102] For a projection device using a single light source 100, taking the illuminance value of the central area at test point A as an example, the luminance value was read in the optical simulation software LightTools, and the luminance uniformity was calculated, yielding a luminance uniformity of 61% for test point A. Similarly, for a projection device using multiple light sources 100, taking the illuminance value of the central area at test point A as an example, the luminance value was read in the optical simulation software LightTools, and the luminance uniformity was calculated, yielding a luminance uniformity of 88% for test point A.

[0103] This shows that, in the same projection device, multiple light sources 100 not only have stronger brightness than a projection device with a single light source 100, but also improve the brightness uniformity at the edge of the projection screen.

[0104] Figure 11 These are comparative diagrams showing the optical structures of multiple illumination sources 101 and a single illumination source 101 provided in the embodiments of this disclosure, as follows: Figure 11 As shown in Figures A and B, the height D1 of the lamp cup in the projection device with two illumination sources 101 is reduced by 19% compared to the height D2 of the lamp cup in the projection device with a single illumination source 101, thereby saving volume space for the projection device and enabling a more compact optical structure layout.

[0105] In terms of the volume of the projection device, under the conditions of the same illumination spot size and similar illumination angle, the height D1 of the lamp cup in the projection device with multiple illumination sources 101 is lower than the height D2 of the lamp cup in the projection device with a single illumination source 101.

[0106] In a projection device with multiple illumination sources 101, the heat dissipation pressure of the light source 100 is lower than that in a projection device with a single illumination source 101. When the total power consumption of the light source 100 is the same, the light source 100 of a projection device with multiple illumination sources 101 dissipates heat faster than that of a projection device with a single collimator 101, thereby improving the efficiency of the optical system and thus enhancing the brightness of the projected image and the stability of the system.

[0107] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A projection device, comprising an illumination assembly, a display panel, and a projection lens, characterized in that, The lighting assembly includes: a plurality of lighting sources, wherein the light emitted by the lighting sources enters the projection lens through the display panel and exits from the projection lens; Wherein, the illumination areas of different lighting sources on the display panel do not overlap at least partially; and the illumination areas of the plurality of lighting sources on the display panel cover the display area of ​​the display panel; The lighting source includes a light source and a lens, with the lens disposed on the light-emitting side of the light source; the lens is used to collimate the light rays from the light source that illuminate the lens. The projection device further includes a second collimating lens, which is disposed on the side of the lens away from the light source, and is used to collimate the light rays from the light source that illuminate the second collimating lens. There is a second intersection point between the optical axis of the illumination source and the second collimating lens, and the optical axis of the illumination source forms an angle with the thickness direction of the display panel, the angle satisfying... d represents the distance between the second intersection point and the optical axis of the second collimating lens; This indicates the focal length of the second collimating lens.

2. The projection device according to claim 1, characterized in that, The lens includes a freeform lens or an aspherical lens.

3. The projection device according to claim 1, characterized in that, The included angle ranges from 0° to 90°.

4. The projection device according to claim 1, characterized in that, The second collimating lens includes a Fresnel lens.

5. The projection device according to claim 1, characterized in that, There is a first intersection point between different optical axes of the different illumination sources; the first intersection point is located on the side of the plurality of illumination sources near the second collimating lens.

6. The projection device according to any one of claims 1 to 5, characterized in that, The plurality of illumination sources are arranged in an array, and the shape of the illumination area of ​​the plurality of illumination sources on the plane of the display panel is the same as the shape of the display area.

7. The projection device according to any one of claims 1 to 5, characterized in that, Also includes: A polarizing assembly is disposed between the light-emitting side of the illumination source and the display panel; The display panel is used to convert the light emitted by the lighting component into first polarized light with a first polarization direction; wherein, the display panel is disposed on the side of the polarizing component away from the lighting component, 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; A reflector is disposed on the side of the display panel away from the polarizing component, for reflecting one of the polarized light in the first polarization direction and the polarized light in the second polarization direction to the projection lens.

8. The projection device according to claim 7, characterized in that, The polarizing component includes: A heat-insulating substrate is disposed between the display panel and the lighting source; A polarizer is disposed on the surface of the heat insulation substrate near the lighting source; the polarizer is used to convert the light emitted by the lighting source into first polarized light with a first polarization direction.

9. The projection device according to claim 7, characterized in that, The reflective assembly includes: an analyzer, a field lens, and a reflector; The analyzer is located between the display panel and the field lens; the analyzer is used to transmit one of the polarized light in the first polarization direction and the polarized light in the second polarization direction. The field lens is positioned between the analyzer and the reflector to focus the light emitted from the analyzer and then emit the focused light to the reflector. The reflector is used to reflect the focused light onto the projection lens.

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