Projection system and method of manufacturing the same

Abstract

The application provides a projection system and a method for manufacturing the projection system. The projection system comprises, in sequence along an optical axis, a light source module for emitting a light beam, an image module having image information, the light beam passing through the image module to form a first light beam carrying the image information, and a projection module having a reflecting element for receiving and reflecting the first light beam to project the image information to a projection surface.

Description

Technical Field

[0001] This application relates to the field of optical technology, and more specifically, to a projection system and a method of manufacturing the projection system. Background Technology

[0002] With the increasing prominence of nighttime driving safety issues, more and more automotive manufacturers are beginning to develop new intelligent vehicle lighting technologies. These new intelligent vehicle lighting technologies are primarily designed to achieve the functions of AFS (Adaptive Front-lighting System) and ADB (Adaptive Driving Beam).

[0003] In practical applications, headlights with AFS (Adaptive Front-lighting) functionality are primarily used to integrate with vehicle detection systems. If the detection system detects other road users (such as oncoming or traveling in the same direction) within the headlight's illumination area, it intelligently adjusts the brightness of that area to avoid dangerous glare. If the detection system detects other road users outside the headlight's illumination area, that area remains brightly lit. Therefore, this technology ensures that vehicles traveling at night provide high-quality illumination for the driver (in vehicles equipped with adaptive headlights) without causing dangerous glare to other road users, thus guaranteeing nighttime driving safety for all parties involved.

[0004] However, existing intelligent vehicle lighting designs, such as DLP (Digital Light Processing) projection headlights based on DMD (Digital Micromirror Device) technology, primarily use traditional lens groups as projection units. While projection lenses composed of lens groups can provide good image quality, the large number of lenses used in the lens group leads to numerous refractions of light within the lens group, making chromatic aberration easy to form and difficult to control, resulting in chromatic aberration in the projection lens. Furthermore, the large number of lenses used in projection lenses makes the entire system large and heavy. Summary of the Invention

[0005] The embodiments proposed in this application can solve or partially solve the deficiencies mentioned in the background section above or other deficiencies in the prior art.

[0006] This application provides a projection system. The projection system, along the optical axis, sequentially includes: a light source module for emitting a light beam; an image module having image information, wherein the light beam is formed by the image module into a first light beam carrying the image information; and a projection module having a reflective element for receiving and reflecting the first light beam to project the image information onto a projection surface.

[0007] In one embodiment, the light source module includes: a light source for emitting a light beam; and a light adjustment element for adjusting the light beam emitted by the light source.

[0008] In one embodiment, the reflective element includes: a first reflective element that receives the first light beam and reflects the first light beam to form a second light beam; and a second reflective element arranged relative to the first reflective element to receive the second light beam and reflect the second light beam onto the projection surface to project the image information onto the projection surface.

[0009] In one embodiment, the first reflective element and the second reflective element are freeform surface mirrors.

[0010] In one embodiment, the projection module includes: n reflective elements, where n ≥ 3; an (n-2)th reflective element that receives and reflects the (n-2)th beam to form an (n-1)th beam; an (n-1)th reflective element arranged relative to the (n-2)th reflective element to receive and reflect the (n-1)th beam to form an nth beam; and an nth reflective element arranged relative to the (n-1)th reflective element to receive and reflect the nth beam to the projection surface, so as to project the image information onto the projection surface.

[0011] In one embodiment, the n reflecting elements are freeform surface mirrors.

[0012] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis and the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis satisfy: L1 / L2≥1.

[0013] In one embodiment, the distance L(n-1) from the center of the (n-2)th reflective element to the center of the (n-1)th reflective element on the optical axis and the distance Ln from the center of the (n-1)th reflective element to the center of the nth reflective element on the optical axis satisfy: L(n-1) / Ln≥1.

[0014] In one embodiment, the vertical distance H1 from the center of the image module to the center of the first reflective element, the vertical distance H2 from the center of the first reflective element to the center of the second reflective element, and the vertical height MH2 of the second reflective element satisfy: 2×(H2-H1) ≥MH2.

[0015] In one embodiment, the maximum field of view (FOV) of the projection system and the image height (H) corresponding to the maximum field of view of the projection system satisfy: FOV / H≥1.

[0016] In one embodiment, the effective focal length F1 of the first reflective element and the total effective focal length F of the projection system satisfy: F1 / F < 2.

[0017] In one embodiment, the effective focal length F1 of the first reflective element and the effective focal length F2 of the second reflective element satisfy: 0.7 < |F1 / F2| < 1.6.

[0018] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis, the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis, the maximum field of view (FOV) of the projection system, and the image height H corresponding to the maximum field of view of the projection system satisfy: (L1+L2) / H / FOV≤1.07.

[0019] In one embodiment, the total effective focal length F of the projection system and the entrance pupil diameter ENPD of the projection system satisfy: F / ENPD≤3.

[0020] In one embodiment, the image module includes at least one of: a digital micromirror device (DMD), a thin-film transistor (TFT), a liquid crystal on silicon (LCOS), and a microelectromechanical system (MEMS).

[0021] In one embodiment, the first reflective element and the second reflective element rotate within a rotation angle range of less than or equal to 4°.

[0022] In one embodiment, the first reflective element and the second reflective element are movable, wherein the distance ΔL2 between the center of the first reflective element and the center of the second reflective element on the optical axis satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0023] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis, the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis, and the total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

[0024] This application also provides a projection system. The projection system includes: an image module for emitting a first light beam carrying image information; and a projection module having a reflective element for receiving and reflecting the first light beam to project the image information onto a projection surface.

[0025] In one embodiment, the reflective element includes: a first reflective element that receives the first light beam and reflects the first light beam to the projection surface to project the image information onto the projection surface.

[0026] In one embodiment, the first reflecting element is a freeform surface mirror.

[0027] In one embodiment, the reflective element includes: a first reflective element that receives the first light beam and reflects the first light beam to form a second light beam; and a second reflective element arranged relative to the first reflective element to receive the second light beam and reflect the second light beam onto the projection surface to project the image information onto the projection surface.

[0028] In one embodiment, the first reflective element and the second reflective element are freeform surface mirrors.

[0029] In one embodiment, the projection module includes: n reflective elements, where n ≥ 3; an (n-2)th reflective element that receives and reflects the (n-2)th beam to form an (n-1)th beam; an (n-1)th reflective element arranged relative to the (n-2)th reflective element to receive and reflect the (n-1)th beam to form an nth beam; and an nth reflective element arranged relative to the (n-1)th reflective element to receive and reflect the nth beam to the projection surface, so as to project the image information onto the projection surface.

[0030] In one embodiment, the n reflecting elements are freeform surface mirrors.

[0031] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis and the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis satisfy: L1 / L2≥1.

[0032] In one embodiment, the distance L(n-1) from the center of the (n-2)th reflective element to the center of the (n-1)th reflective element on the optical axis and the distance Ln from the center of the (n-1)th reflective element to the center of the nth reflective element on the optical axis satisfy: L(n-1) / Ln≥1.

[0033] In one embodiment, the vertical distance H1 from the center of the image module to the center of the first reflective element, the vertical distance H2 from the center of the first reflective element to the center of the second reflective element, and the vertical height MH2 of the second reflective element satisfy: 2×(H2-H1)≥MH2.

[0034] In one embodiment, the maximum field of view (FOV) of the projection system and the image height (H) corresponding to the maximum field of view of the projection system satisfy: FOV / H≥1.

[0035] In one embodiment, the effective focal length F1 of the first reflective element and the total effective focal length F of the projection system satisfy: F1 / F < 2.

[0036] In one embodiment, the effective focal length F1 of the first reflective element and the effective focal length F2 of the second reflective element satisfy: 0.7 < |F1 / F2| < 1.6.

[0037] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis, the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis, the maximum field of view (FOV) of the projection system, and the image height H corresponding to the maximum field of view of the projection system satisfy: (L1+L2) / H / FOV≤1.07.

[0038] In one embodiment, the total effective focal length F of the projection system and the entrance pupil diameter ENPD of the projection system satisfy: F / ENPD≤3.

[0039] In one embodiment, the image module is a light-emitting diode (LED).

[0040] In one embodiment, the first reflective element and the second reflective element rotate within a rotation angle range of less than or equal to 4°.

[0041] In one embodiment, the first reflective element and the second reflective element are movable, wherein the distance ΔL2 between the center of the first reflective element and the center of the second reflective element on the optical axis satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0042] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis, the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis, and the total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

[0043] This application also provides a method for manufacturing a projection system. The method includes: setting a light source module for emitting a light beam; placing an image module having image information in the optical path of the light beam, the light beam forming a first light beam carrying the image information via the image module; and placing a projection module in the optical path of the first light beam, wherein the projection module has a reflective element for receiving and reflecting the first light beam to project the image information onto a projection surface.

[0044] In one embodiment, the light source module includes a light adjustment element for adjusting the light beam.

[0045] In one embodiment, placing the projection module in the optical path of the first beam includes: setting a first reflective element to receive the first beam and reflect the first beam to form a second beam; and setting a second reflective element relative to the first reflective element to receive the second beam and reflect the second beam to the projection surface, so as to project the image information onto the projection surface.

[0046] In one embodiment, placing the projection module in the optical path of the first beam includes: setting n reflective elements, where n≥3, wherein the (n-2)th reflective element receives the (n-2)th beam and reflects the (n-2)th beam to form the (n-1)th beam; the (n-1)th reflective element receives the (n-1)th beam and reflects the (n-1)th beam to form the nth beam; and the nth reflective element receives the nth beam and reflects the nth beam to the projection surface, so as to project the image information onto the projection surface.

[0047] In one embodiment, the first reflective element and the second reflective element are configured to rotate within a rotation angle range of less than or equal to 4°.

[0048] In one embodiment, the first reflective element and the second reflective element are configured to be movable, wherein the distance ΔL2 between the center of the first reflective element and the center of the second reflective element on the optical axis satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0049] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis, the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis, and the total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

[0050] This application also provides a method for manufacturing a projection system. The method includes: setting an image module for emitting a first light beam carrying image information; and placing a projection module in the optical path of the first light beam, wherein the projection module has a reflective element for receiving and reflecting the first light beam to project the image information onto a projection surface.

[0051] In one embodiment, placing the projection module in the optical path of the first beam includes: setting a first reflective element to receive the first beam and reflect the first beam to form a second beam; and setting a second reflective element to receive the second beam and reflect the second beam to the projection surface, so as to project the image information onto the projection surface.

[0052] In one embodiment, placing the projection module in the optical path of the first beam includes: setting n reflective elements, where n≥3, wherein the (n-2)th reflective element receives the (n-2)th beam and reflects the (n-2)th beam to form the (n-1)th beam; the (n-1)th reflective element receives the (n-1)th beam and reflects the (n-1)th beam to form the nth beam; and the nth reflective element receives the nth beam and reflects the nth beam to the projection surface, so as to project the image information onto the projection surface.

[0053] In one embodiment, the first reflective element and the second reflective element are configured to rotate within a rotation angle range of less than or equal to 4°.

[0054] In one embodiment, the first reflective element and the second reflective element are configured to be movable, wherein the distance ΔL2 between the center of the first reflective element and the center of the second reflective element on the optical axis satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0055] In one embodiment, the distance L1 from the center of the image module to the center of the first reflective element on the optical axis, the distance L2 from the center of the first reflective element to the center of the second reflective element on the optical axis, and the total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

[0056] The projection system and manufacturing method thereof provided in this application have at least one of the following advantages:

[0057] 1) The projection system provided in this application uses reflective elements to reflect light, which can effectively reduce system color difference;

[0058] 2) The projection system provided in this application has a compact structure and is small in size and weight;

[0059] 3) The projection system provided in this application has fewer components, which is beneficial to improving light utilization and reducing processing costs;

[0060] 4) The projection system provided in this application can effectively change the projection direction by altering the number of reflective elements and the rotation angle; and

[0061] 5) The projection system provided in this application can effectively achieve zoom function by changing the interval distance between multiple reflective elements, and can adjust the size of the image on the projection surface. Attached Figure Description

[0062] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0063] Figure 1 This is a schematic diagram illustrating the parameters of a projection system according to an embodiment of this application;

[0064] Figure 2A This is a schematic diagram of the projection system according to an embodiment of this application;

[0065] Figure 2B This is a schematic diagram of the structure of another projection system according to an embodiment of this application;

[0066] Figure 3 This is a schematic diagram of the structure of another projection system according to an embodiment of this application;

[0067] Figure 4 This is a schematic diagram of the structure of another projection system according to an embodiment of this application;

[0068] Figure 5 This is a schematic diagram of the structure of another projection system according to an embodiment of this application;

[0069] Figure 6 This is a schematic diagram of the structure of another projection system according to an embodiment of this application;

[0070] Figure 7 This is a flowchart of a method for manufacturing a projection system according to an embodiment of this application; and

[0071] Figure 8 This is a flowchart of another method for manufacturing a projection system according to an embodiment of this application. Detailed Implementation

[0072] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0073] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features, especially not any order of precedence. Therefore, without departing from the teachings of this application, the first film layer discussed herein may also be referred to as the second film layer, and vice versa.

[0074] In the accompanying drawings, the thickness, dimensions, and shapes of the parts have been slightly adjusted for ease of illustration. The drawings are for illustrative purposes only and are not drawn to scale. As used herein, the terms “approximately,” “about,” and similar terms are used as expressions of approximation, not as expressions of degree, and are intended to illustrate inherent deviations in measured or calculated values ​​that will be recognized by one of ordinary skill in the art.

[0075] It should also be understood that expressions such as "comprising," "including," "having," "containing," and / or "comprising" are open-ended rather than closed-ended expressions in this specification, indicating the presence of the stated features, elements, and / or components, but not excluding the presence of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not just individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0076] Unless otherwise specified, all terms used herein (including engineering and technical terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that, unless expressly stated herein, terms defined in common dictionaries shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or overly formalized meaning.

[0077] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0078] The features, principles and other aspects of this application are described in detail below.

[0079] This application provides a projection system. The projection system may include a light source module, an image module, and a projection module, wherein the light source module, image module, and projection module are arranged sequentially along the optical axis. Any two of the light source module, image module, and projection module may have a gap between them.

[0080] In an exemplary embodiment, the light source module can be used to emit a light beam, wherein the light beam emitted by the light source module can be an approximately parallel light beam. For example, the light source module may include a light source and a light adjustment element, wherein the light source can emit light to the light adjustment element, and the light adjustment element can adjust the light emitted by the light source to form an approximately parallel light beam.

[0081] In an exemplary embodiment, the image module may have image information. The image module may include at least one of a digital micromirror device (DMD), a thin-film transistor (TFT), a liquid crystal on silicon (LCOS), and a microelectromechanical system (MEMS). For example, the image module is a DMD that integrates a reflective micromirror array and a memory on the same chip to reflect light carrying image information. In this application, a parallel light beam can be formed into a first light beam carrying image information via the image module. For example, a parallel light beam can be reflected by the image module to form a first light beam carrying image information.

[0082] In an exemplary embodiment, the projection module can receive and reflect a first light beam to project image information onto a projection surface. For example, the projection module may include a first reflective element and a second reflective element. The first and second reflective elements can be freeform surface mirrors. The first reflective element can receive the first light beam and then reflect it to form a second light beam. The second reflective element can receive the second light beam and then reflect it onto the projection surface to project image information onto the projection surface. This application achieves a projection imaging effect by employing multiple freeform surface mirrors (e.g., two), which can project image information from the image module onto the target surface (i.e., the projection surface). In particular, while ensuring clear projection, the positions of the mirrors among the multiple freeform surface mirrors can be placed in any suitable position. It should be understood that this application does not specifically limit the number of reflective elements; in practical applications, any number of reflective elements can be reasonably set to achieve the projection purpose.

[0083] In an exemplary embodiment, this application can fabricate a freeform surface mirror by machining metal or glass materials using a turning process. Alternatively, it can be fabricated by molding glass materials using a mold pressing process, or by injection molding plastic materials using a mold injection process. This application employs the principle of reflective imaging, which prevents light refraction during transmission within the system, ensuring that light of different wavelengths always travels along the same path, thus reducing the impact of projection chromatic aberration.

[0084] In an exemplary embodiment, the projection module may include n reflective elements, where n ≥ 3. The n reflective elements are freeform surface mirrors. The (n-2)th reflective element may receive the (n-2)th beam and reflect it to form the (n-1)th beam. The (n-1)th reflective element may receive the (n-1)th beam and reflect it to form the nth beam. The nth reflective element may receive the nth beam and reflect it onto the projection surface to project image information onto the projection surface. For example, when n = 3, the projection module may include 3 reflective elements, i.e., the projection module may include a first reflective element, a second reflective element, and a third reflective element. The first reflective element may receive the first beam and then reflect it to form the second beam. The second reflective element may receive the second beam and then reflect it to form the third beam. The third reflective element may receive the third beam and then reflect it onto the projection surface to project image information onto the projection surface.

[0085] This application also provides a projection system. The projection system may include an image module and a projection module, wherein the image module and the projection module are sequentially arranged along the optical axis. There may be a gap between the image module and the projection module. The image module can be used to emit a first light beam carrying image information. For example, the image module can be an actively light-emitting optical element such as a light-emitting diode (LED), which is beneficial for reducing costs and correcting chromatic aberration. The projection module can receive and reflect the first light beam to project the image information onto a projection surface. It should be understood that this application also does not specifically limit the number of reflective elements in the projection system; in practical applications, any number of reflective elements can be reasonably arranged to achieve the projection purpose.

[0086] In an exemplary embodiment, the projection system according to this application satisfies: L1 / L2≥1, where L1 is the distance on the optical axis from the center of the image module to the center of the first reflective element, and L2 is the distance on the optical axis from the center of the first reflective element to the center of the second reflective element. More specifically, L1 and L2 can further satisfy: L1 / L2≥1.1. Satisfying L1 / L2≥1 allows the distance from the second freeform surface mirror to the first freeform surface mirror to be less than the distance from the image module to the first freeform surface mirror. This is beneficial for making the projection system smaller and more compact, thus facilitating miniaturization, and also for increasing the installation space of the projection system.

[0087] In an exemplary embodiment, the projection system according to this application satisfies: L(n-1) / Ln ≥ 1, where L(n-1) is the distance on the optical axis from the center of the (n-2)th reflective element to the center of the (n-1)th reflective element, and Ln is the distance on the optical axis from the center of the (n-1)th reflective element to the center of the nth reflective element. More specifically, L(n-1) and Ln further satisfy: L(n-1) / Ln ≥ 1.1. Satisfying L(n-1) / Ln ≥ 1 ensures that the distance from the nth freeform surface mirror to the (n-1)th freeform surface mirror is less than the distance from the (n-2)th freeform surface mirror to the (n-1)th freeform surface mirror. This is beneficial for making the projection system smaller and more compact, thus facilitating miniaturization, and also for increasing the installation space of the projection system.

[0088] In an exemplary embodiment, the projection system according to this application satisfies: 2 × (H2-H1) ≥ MH2, where, as Figure 1 As shown, H1 is the vertical distance from the center of the image module to the center of the first reflective element, H2 is the vertical distance from the center of the first reflective element to the center of the second reflective element, and MH2 is the vertical height of the second reflective element. Satisfying 2×(H2-H1)≥MH2 allows for a reserved space in the vertical direction between the second and first freeform surface mirrors, preventing interference between the reflective elements and light transmission, and ensuring that light is not blocked by the reflective elements.

[0089] In an exemplary embodiment, the projection system according to this application satisfies: FOV / H≥1, where FOV is the maximum field of view of the projection system, and H is the image height corresponding to the maximum field of view of the projection system. Satisfying FOV / H≥1 allows the projection system to have a larger projection area, thereby ensuring that the projection system has a larger magnification.

[0090] In an exemplary embodiment, the projection system according to this application satisfies: F1 / F < 2, where F1 is the effective focal length of the first reflective element and F is the total effective focal length of the projection system. More specifically, F1 and F may further satisfy: F1 / F < 1.4. Satisfying F1 / F < 2 allows the first reflective element to have a larger optical power, making it easier for the first reflective element to collect the light beam emitted by the image module, thereby improving the light transmission capability of the projection system.

[0091] In an exemplary embodiment, the projection system according to this application satisfies: 0.7 < |F1 / F2| < 1.6, where F1 is the effective focal length of the first reflecting element and F2 is the effective focal length of the second reflecting element. Satisfying 0.7 < |F1 / F2| < 1.6 allows the effective focal lengths of the first and second reflecting elements to be close, thereby enabling a smooth transition of light rays emitted from the first reflecting element to the second reflecting element, which helps to reduce system aberrations.

[0092] In an exemplary embodiment, the projection system according to this application satisfies: (L1+L2) / H / FOV≤1.07, where L1 is the distance on the optical axis from the center of the image module to the center of the first reflective element, L2 is the distance on the optical axis from the center of the first reflective element to the center of the second reflective element, FOV is the maximum field of view of the projection system, and H is the image height corresponding to the maximum field of view of the projection system. Satisfying (L1+L2) / H / FOV≤1.07 allows for an effective reduction in the overall length of the projection system while maintaining the same projection surface and image height, thus facilitating system miniaturization.

[0093] In an exemplary embodiment, the projection system according to this application satisfies: F / ENPD ≤ 3, where F is the total effective focal length of the projection system and ENPD is the entrance pupil diameter of the projection system. More specifically, F and ENPD further satisfy: F / ENPD ≤ 1.8. Satisfying F / ENPD ≤ 3 can increase the amount of light entering the system, ensuring that the system has a large luminous flux, thereby improving the luminous efficiency of the system and making the pattern projected onto the projection surface brighter.

[0094] In an exemplary embodiment, the projection system according to this application satisfies: (L1+L2) / F ≤ 4, where L1 is the distance on the optical axis from the center of the image module to the center of the first reflective element, L2 is the distance on the optical axis from the center of the first reflective element to the center of the second reflective element, and F is the total effective focal length of the projection system. Satisfying (L1+L2) / F ≤ 4 controls the overall system length and ensures system miniaturization.

[0095] In an exemplary embodiment, the first reflecting element and the second reflecting element can rotate at a rotation angle of less than or equal to 4°. The first reflecting element and the second reflecting element can rotate at rotation angles θ1 and θ2, respectively, where θ1 and θ2 are both less than or equal to 4°. By rotating the first reflecting element and the second reflecting element, the direction of the light beam emitted from the first reflecting element and the second reflecting element can be changed, which is beneficial for changing the projection direction and for adjusting the projection sharpness on the projection surface.

[0096] In an exemplary embodiment, the first and second reflective elements are movable. The optical imaging lens according to this application satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm, where ΔL2 is the distance along the optical axis from the center of the first reflective element to the center of the second reflective element. More specifically, ΔL2 further satisfies: -0.25mm ≤ ΔL2 ≤ 0.25mm. Satisfying -0.5mm ≤ ΔL2 ≤ 0.5mm allows the zoom function of the projection system to be achieved by adjusting the distance between the first and second reflective elements.

[0097] Specific embodiments of the projection system applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0098] Example 1

[0099] like Figure 2A This is a schematic diagram of the projection system 1000 according to Embodiment 1 of this application.

[0100] The projection system 1000 may include a light source module 1100, an image module 1200, and a projection module 1300 arranged sequentially along the optical axis.

[0101] The light source module 1100 may include a light source 1110 and a light adjustment element 1120, wherein the light source can emit light to the light adjustment element, and the light adjustment element can adjust the light emitted by the light source to form an approximately parallel beam. The image module 1200 can receive the parallel beam emitted from the light source module 1100 and reflect the received parallel beam to form a first beam carrying image information. The projection module 1300 may include a first reflective element 1310 and a second reflective element 1320. The first reflective element 1310 can receive the first beam and then reflect the first beam to form a second beam. The second reflective element 1320 can receive the second beam and then reflect the second beam onto the projection surface 100 to project the image information carried by the second beam onto the projection surface 100, ultimately forming a magnified projected image on the projection surface 100.

[0102] In this example, the distance L1 from the center of the image module 1200 to the center of the first reflective element 1310 on the optical axis can be 84.682 mm; the distance L2 from the center of the first reflective element 1310 to the center of the second reflective element 1320 on the optical axis can be 71.865 mm; the vertical distance H1 from the center of the image module 1200 to the center of the first reflective element 1310 can be 13.731 mm; the vertical distance H2 from the center of the first reflective element 1310 to the center of the second reflective element 1320 can be 38.598 mm; the vertical projection height MH1 of the first reflective element can be 52 mm; the vertical height MH2 of the second reflective element can be 24 mm; the maximum field of view (FOV) of the projection system can be 19.3°; the image height H corresponding to the maximum field of view of the projection system can be 13.9 mm; the effective focal length F1 of the first reflective element can be 58.171 mm; and the effective focal length F2 of the second reflective element can be -39.796 mm. mm; the total effective focal length F of the projection system can be 42.946 mm; and the entrance pupil diameter ENPD of the projection system can be 26.8 mm.

[0103] Example 2

[0104] like Figure 2B This is a schematic diagram of the projection system 1000 according to Embodiment 2 of this application. In this embodiment and the following embodiments, for the sake of brevity, descriptions similar to those in Embodiment 1 will be omitted.

[0105] The projection system 1000 may include a light source module 1100, an image module 1200, and a projection module 1300 arranged sequentially along the optical axis.

[0106] The light source module 1100 may include a light source 1110 and a light adjustment element 1120, wherein the light source can emit light to the light adjustment element, and the light adjustment element can adjust the light emitted by the light source to form a parallel beam. The image module 1200 can receive the parallel beam emitted from the light source module 1100 and reflect the received parallel beam to form a first beam carrying image information. The projection module 1300 may include a first reflective element 1310, a second reflective element 1320, and a third reflective element 1330. The first reflective element 1310 can receive the first beam and then reflect the first beam to form a second beam. The second reflective element 1320 can receive the second beam and then reflect the second beam to form a third beam. The third reflective element 1330 can receive the third beam and then reflect the third beam to the projection surface 100 to project the image information carried by the third beam onto the projection surface 100, ultimately forming a magnified projected image on the projection surface 100.

[0107] Example 3

[0108] like Figure 3 This is a schematic diagram of the projection system 1000 according to Embodiment 3 of this application.

[0109] The projection system 1000 may include an image module 1200 and a projection module 1300 arranged sequentially along the optical axis.

[0110] The image module 1200 can emit a first beam carrying image information. The projection module 1300 can receive the first beam and then project the first beam onto the reflective projection surface 100 to project the image information carried by the first beam onto the projection surface 100, ultimately forming an enlarged projected image on the projection surface 100.

[0111] Example 4

[0112] like Figure 4 This is a schematic diagram of the projection system 1000 according to Embodiment 4 of this application.

[0113] The projection system 1000 may include an image module 1200 and a projection module 1300 arranged sequentially along the optical axis.

[0114] The image module 1200 can emit a first light beam carrying image information. The projection module 1300 may include a first reflective element 1310 and a second reflective element 1320. The first reflective element 1310 can receive the first light beam and then reflect it to form a second light beam. The second reflective element 1320 can receive the second light beam and then reflect it onto the projection surface 100 to project the image information carried by the second light beam onto the projection surface 100, ultimately forming a magnified projected image on the projection surface 100.

[0115] Example 5

[0116] like Figure 5 This is a schematic diagram of the projection system 1000 according to Embodiment 5 of this application.

[0117] The projection system 1000 may include an image module 1200 and a projection module 1300 arranged sequentially along the optical axis.

[0118] The image module 1200 can emit a first light beam carrying image information. The projection module 1300 may include a first reflective element 1310 and a second reflective element 1320. The first reflective element 1310 can receive the first light beam and then reflect it to form a second light beam. The second reflective element 1320 can receive the second light beam and then reflect it onto the projection surface 100 to project the image information carried by the second light beam onto the projection surface 100, ultimately forming a magnified projected image on the projection surface 100.

[0119] In this example, the first reflecting element 1310 and the second reflecting element 1320 can rotate in the direction indicated by the arrow in Figure 5 and within a rotation angle range of less than or equal to 4°, thereby changing the direction of the light beam emitted from the first reflecting element 1310 and the second reflecting element 1320, which is beneficial for changing the light beam transmission direction and the projection direction.

[0120] Example 6

[0121] like Figure 6 This is a schematic diagram of the projection system 1000 according to Embodiment 6 of this application.

[0122] The projection system 1000 may include an image module 1200 and a projection module 1300 arranged sequentially along the optical axis.

[0123] The image module 1200 can emit a first light beam carrying image information. The projection module 1300 may include a first reflective element 1310 and a second reflective element 1320. The first reflective element 1310 can receive the first light beam and then reflect it to form a second light beam. The second reflective element 1320 can receive the second light beam and then reflect it onto the projection surface 100 to project the image information carried by the second light beam onto the projection surface 100, ultimately forming a magnified projected image on the projection surface 100.

[0124] In this example, the first reflective element 1310 and the second reflective element 1320 can be moved along the direction of the double arrows in Figure 6, thereby achieving the zoom function of the projection system by adjusting the interval between the first reflective element 1310 and the second reflective element 1320. The distance ΔL2 between the first reflective element 1310 and the second reflective element 1320 on the optical axis can satisfy -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0125] This application also provides a method for manufacturing the above-described projection system. Figure 7 This is a flowchart of a method for manufacturing a projection system according to an embodiment of this application.

[0126] The method 2000 for manufacturing a projection system may include: step 2100, setting a light source module for emitting a parallel beam; step 2200, setting an image module having image information in the optical path of the parallel beam, the parallel beam forming a first beam carrying image information via the image module; and step 2300, setting a projection module in the optical path of the first beam, wherein the projection module receives and reflects the first beam to project image information onto a projection surface.

[0127] In step 2100, the light source module includes a light adjustment element to adjust the light into a parallel beam.

[0128] In step 2300, setting the projection module in the optical path of the first beam includes: setting a first reflective element to receive the first beam and reflect the first beam to form a second beam; and setting a second reflective element relative to the first reflective element to receive the second beam and reflect the second beam to the projection surface, so as to project image information onto the projection surface.

[0129] In another embodiment, step 2300, setting the projection module in the optical path of the first beam includes: setting n reflective elements, where n≥3, wherein the (n-2)th reflective element receives the (n-2)th beam and reflects the (n-2)th beam to form the (n-1)th beam; the (n-1)th reflective element receives the (n-1)th beam and reflects the (n-1)th beam to form the nth beam; and the nth reflective element receives the nth beam and reflects the nth beam to the projection surface, so as to project image information onto the projection surface.

[0130] In an exemplary embodiment, the method 2000 described above may include: a first reflective element and a second reflective element being configured to rotate within a rotation angle range of less than or equal to 4°.

[0131] In an exemplary embodiment, the method 2000 described above may include: a first reflective element and a second reflective element being configured to be movable, wherein the distance ΔL2 between the center of the first reflective element and the center of the second reflective element on the optical axis satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0132] This application also provides a method for manufacturing the above-described projection system. Figure 8 This is a flowchart of a method 3000 for manufacturing a projection system according to an embodiment of this application.

[0133] The method 3000 for manufacturing a projection system may include: step 3100, setting up an image module for emitting a first beam carrying image information; step 3200, placing a projection module in the optical path of the first beam, wherein the projection module receives and reflects the first beam to project image information onto a projection surface.

[0134] In step 3200, setting the projection module in the optical path of the first beam includes: setting a first reflective element to receive the first beam and reflect the first beam to form a second beam; and setting a second reflective element to receive the second beam and reflect the second beam to the projection surface, so as to project image information onto the projection surface.

[0135] In another embodiment, step 3200, setting the projection module in the optical path of the first beam includes: setting n reflective elements, where n≥3, wherein the (n-2)th reflective element receives the (n-2)th beam and reflects the (n-2)th beam to form the (n-1)th beam; the (n-1)th reflective element receives the (n-1)th beam and reflects the (n-1)th beam to form the nth beam; and the nth reflective element receives the nth beam and reflects the nth beam to the projection surface, so as to project image information onto the projection surface.

[0136] In an exemplary embodiment, the method 3000 described above may include: a first reflective element and a second reflective element being configured to rotate within a rotation angle range of less than or equal to 4°.

[0137] In an exemplary embodiment, the method 3000 described above may include: a first reflective element and a second reflective element being configured to be movable, wherein the distance ΔL2 between the center of the first reflective element and the center of the second reflective element on the optical axis satisfies: -0.5mm ≤ ΔL2 ≤ 0.5mm.

[0138] The above description is merely an illustration of the embodiments of this application and the technical principles employed. Those skilled in the art should understand that the scope of protection involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the described technical concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A projection system, characterized by, sequentially include, along an optical axis direction: a light source module configured to emit a light beam; an image module having image information, the light beam passing through the image module to form a first light beam carrying the image information; and a projection module configured to receive and reflect the first light beam to project the image information to a projection surface, wherein the projection module includes a first reflecting element and a second reflecting element, an effective focal length F1 of the first reflecting element and an effective focal length F2 of the second reflecting element satisfy: 0.7 < |F1 / F2| < 1.6; a distance L1 between a center of the image module and a center of the first reflecting element on the optical axis, a distance L2 between the center of the first reflecting element and a center of the second reflecting element on the optical axis, a maximum field of view FOV of the projection system, and an image height H corresponding to the maximum field of view of the projection system satisfy: (L1+L2) / H / FOV×1°≤1.

07.

2. The projection system of claim 1, wherein, the light source module includes: a light source configured to emit a light beam; and a light adjusting element configured to adjust the light beam emitted by the light source.

3. The projection system of claim 1, wherein: the first reflecting element receives the first light beam and reflects the first light beam to form a second light beam; and the second reflecting element is arranged relative to the first reflecting element to be capable of receiving the second light beam and reflecting the second light beam to the projection surface to project the image information to the projection surface.

4. The projection system of claim 3, wherein, the first reflecting element and the second reflecting element are free-form reflecting mirrors.

5. The projection system of claim 1, wherein, the projection module includes: n reflecting elements, where n≥3, an (n-2)th reflecting element configured to receive an (n-2)th light beam and reflect the (n-2)th light beam to form an (n-1)th light beam; an (n-1)th reflecting element arranged relative to the (n-2)th reflecting element to be capable of receiving the (n-1)th light beam and reflecting the (n-1)th light beam to form an nth light beam; and an nth reflecting element arranged relative to the (n-1)th reflecting element to be capable of receiving the nth light beam and reflecting the nth light beam to the projection surface to project the image information to the projection surface.

6. The projection system of claim 5, wherein, the n reflecting elements are free-form reflecting mirrors.

7. The projection system according to any one of claims 3-6, wherein, a distance L1 between a center of the image module and a center of the first reflecting element on the optical axis and a distance L2 between the center of the first reflecting element and a center of the second reflecting element on the optical axis satisfy: L1 / L2≥1.

8. The projection system according to claim 5 or 6, characterized in that, a distance L(n-1) between a center of the (n-2)th reflecting element and a center of the (n-1)th reflecting element on the optical axis and a distance Ln between the center of the (n-1)th reflecting element and a center of the nth reflecting element on the optical axis satisfy: L(n-1) / Ln≥1.

9. The projection system according to any one of claims 3-6, wherein, a distance H1 between a center of the image module and a center of the first reflecting element in a vertical direction, a distance H2 between the center of the first reflecting element and a center of the second reflecting element in the vertical direction, and a height MH2 of the second reflecting element in the vertical direction satisfy: 2×(H2-H1)≥MH2.

10. The projection system according to any one of claims 3-6, wherein, A maximum field of view FOV of the projection system and an image height H corresponding to the maximum field of view FOV of the projection system satisfy: FOV / H≥1 ° / mm.

11. The projection system according to any one of claims 3-6, wherein, An effective focal length F1 of the first reflective element and a total effective focal length F of the projection system satisfy: F1 / F<2.

12. The projection system according to any one of claims 3-6, wherein, The total effective focal length F of the projection system and an entrance pupil diameter ENPD of the projection system satisfy: F / ENPD≤3.

13. The projection system according to any one of claims 3-6, wherein, The image module includes at least one of a digital micro-mirror device (DMD), a thin film transistor (TFT), a liquid crystal on silicon (LCOS), and a micro electro mechanical system (MEMS).

14. The projection system according to any one of claims 3-6, wherein, The first reflective element and the second reflective element are rotatable within a rotation angle range less than or equal to 4°.

15. The projection system according to any one of claims 3-6, wherein, The first reflective element and the second reflective element are movable, wherein a distance ΔL2 between a center of the first reflective element and a center of the second reflective element on the optical axis satisfies: -0.5 mm≤ΔL2≤0.5 mm.

16. The projection system according to any one of claims 3-6, wherein, A distance L1 between a center of the image module and a center of the first reflective element on the optical axis, a distance L2 between the center of the first reflective element and a center of the second reflective element on the optical axis, and a total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

17. A projection system, characterized by Comprising: an image module configured to emit a first light beam carrying image information; and a projection module configured to receive and reflect the first light beam to project the image information to a projection surface, wherein the projection module comprises a first reflective element and a second reflective element, an effective focal length F1 of the first reflective element and an effective focal length F2 of the second reflective element satisfy: 0.7<|F1 / F2|<1.6; a distance L1 between a center of the image module and a center of the first reflective element on an optical axis, a distance L2 between the center of the first reflective element and a center of the second reflective element on the optical axis, a maximum field of view FOV of the projection system, and an image height H corresponding to the maximum field of view FOV of the projection system satisfy: (L1+L2) / H / FOV×1°≤1.

07.

18. The projection system of claim 17, wherein the first reflective element is configured to receive the first light beam and reflect the first light beam to form a second light beam; and the second reflective element is arranged relative to the first reflective element to be capable of receiving the second light beam and reflecting the second light beam to the projection surface to project the image information to the projection surface.

19. The projection system of claim 18, wherein, The first reflective element and the second reflective element are freeform mirrors.

20. The projection system of claim 17, wherein, The projection module comprises n reflective elements, where n≥3, an (n-2)th reflective element configured to receive an (n-2)th light beam and reflect the (n-2)th light beam to form an (n-1)th light beam; an (n-1)th reflective element arranged relative to the (n-2)th reflective element to be capable of receiving the (n-1)th light beam and reflecting the (n-1)th light beam to form an nth light beam; and an nth reflective element arranged relative to the (n-1)th reflective element to be capable of receiving the nth light beam and reflecting the nth light beam to the projection surface to project the image information to the projection surface.

21. The projection system of claim 20, wherein, The n reflective elements are free-form mirrors.

22. The projection system according to any of claims 18-21, characterized in that, A distance L1 on an optical axis from a center of the image module to a center of the first reflective element and a distance L2 on the optical axis from the center of the first reflective element to a center of the second reflective element satisfy: L1 / L2≥1.

23. The projection system of claim 20 or 21, wherein, A distance L(n-1) on an optical axis from a center of the n-2 reflective element to a center of the n-1 reflective element and a distance Ln on the optical axis from the center of the n-1 reflective element to a center of the n reflective element satisfy: L(n-1) / Ln≥1.

24. The projection system according to any one of claims 18-21, wherein, A distance H1 in a vertical direction from the center of the image module to the center of the first reflective element, a distance H2 in the vertical direction from the center of the first reflective element to a center of the second reflective element, and a height MH2 of the second reflective element in the vertical direction satisfy: 2×(H2-H1)≥MH2.

25. The projection system according to any one of claims 18-21, wherein, A maximum field of view FOV of the projection system and an image height H corresponding to the maximum field of view FOV of the projection system satisfy: FOV / H≥1 ° / mm.

26. The projection system according to any one of claims 18-21, wherein, An effective focal length F1 of the first reflective element and a total effective focal length F of the projection system satisfy: F1 / F<2.

27. The projection system according to any of claims 18-21, characterized by, The total effective focal length F of the projection system and an entrance pupil diameter ENPD of the projection system satisfy: F / ENPD≤3.

28. The projection system according to any one of claims 18-21, wherein, The image module is a light emitting diode LED.

29. The projection system according to any one of claims 18-21, wherein, The first reflective element and the second reflective element are rotatable within a rotation angle range less than or equal to 4°.

30. The projection system according to any one of claims 18-21, wherein, The first reflective element and the second reflective element are movable, wherein a distance ΔL2 on an optical axis from a center of the first reflective element to a center of the second reflective element satisfies: -0.5 mm≤ΔL2≤0.5 mm.

31. The projection system according to any of claims 18-21, characterized by, A distance L1 on an optical axis from a center of the image module to a center of the first reflective element, a distance L2 on the optical axis from the center of the first reflective element to a center of the second reflective element, and a total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

32. A method for manufacturing a projection system, comprising: providing a light source module for emitting a light beam; providing an image module having image information on an optical path of the light beam, the light beam forming a first light beam carrying the image information via the image module; and providing a projection module on an optical path of the first light beam, wherein the projection module is configured to receive and reflect the first light beam to project the image information to a projection surface, wherein the projection module comprises a first reflective element and a second reflective element, an effective focal length F1 of the first reflective element and an effective focal length F2 of the second reflective element satisfy: 0.7<|F1 / F2|<1.6; a distance L1 on an optical axis from a center of the image module to a center of the first reflective element, a distance L2 on the optical axis from the center of the first reflective element to a center of the second reflective element, a maximum field of view FOV of the projection system, and an image height H corresponding to the maximum field of view FOV of the projection system satisfy: (L1+L2) / H / FOV×1°≤1.

07.

33. The method of claim 32, wherein, The light source module comprises a light adjusting element for adjusting the light beam.

34. The method of claim 32, wherein, The projection module is arranged on the light path of the first light beam, comprising: The first reflecting element is arranged to receive the first light beam and reflect the first light beam to form a second light beam; and The second reflecting element is arranged relative to the first reflecting element to receive the second light beam and reflect the second light beam to the projection surface to project the image information to the projection surface.

35. The method of claim 32, wherein, The projection module is arranged on the light path of the first light beam, comprising: The first reflecting element is arranged to receive the first light beam and reflect the first light beam to form a second light beam; and The second reflecting element is arranged relative to the first reflecting element to receive the second light beam and reflect the second light beam to the projection surface to project the image information to the projection surface. The projection module is arranged on the light path of the first light beam, comprising:

36. The method of claim 34 or 35, wherein, The first reflecting element is arranged to receive the first light beam and reflect the first light beam to form a second light beam; and 37. The method of claim 34 or 35, wherein, The second reflecting element is arranged relative to the first reflecting element to receive the second light beam and reflect the second light beam to the projection surface to project the image information to the projection surface.

38. The method of claim 34 or 35, wherein, The first reflecting element and the second reflecting element are configured to rotate within a rotation angle range less than or equal to 4°. The first reflecting element and the second reflecting element are configured to be movable, wherein a distance ΔL2 between a center of the first reflecting element and a center of the second reflecting element on an optical axis satisfies: -0.5 mm ≤ ΔL2 ≤ 0.5 mm. A distance L1 between a center of the image module and a center of the first reflecting element on an optical axis, a distance L2 between a center of the first reflecting element and a center of the second reflecting element on the optical axis, and a total effective focal length F of the projection system satisfy: (L1+L2) / F ≤ 4.

39. A method for manufacturing a projection system, comprising: arranging an image module for emitting a first light beam carrying image information; and arranging a projection module on the light path of the first light beam, wherein the projection module is configured to receive and reflect the first light beam to project the image information to a projection surface, 40. The method of claim 39, wherein, wherein the projection module comprises a first reflecting element and a second reflecting element, an effective focal length F1 of the first reflecting element and an effective focal length F2 of the second reflecting element satisfy: 0.7 < |F1 / F2| < 1.6; a distance L1 between a center of the image module and a center of the first reflecting element on an optical axis, a distance L2 between a center of the first reflecting element and a center of the second reflecting element on the optical axis, a maximum field of view angle FOV of the projection system, and an image height H corresponding to the maximum field of view angle of the projection system satisfy: (L1+L2) / H / FOV×1° ≤ 1.

07. The projection module is arranged on the light path of the first light beam, comprising:

41. The method of claim 39, wherein, The first reflecting element is arranged to receive the first light beam and reflect the first light beam to form a second light beam; and The second reflecting element is arranged relative to the first reflecting element to receive the second light beam and reflect the second light beam to the projection surface to project the image information to the projection surface. The projection module is arranged on the light path of the first light beam, comprising: The first reflecting element is arranged to receive the first light beam and reflect the first light beam to form a second light beam; and The second reflecting element is arranged relative to the first reflecting element to receive the second light beam and reflect the second light beam to the projection surface to project the image information to the projection surface. The (n-2)th reflective element receives the (n-2)th light beam and reflects the (n-2)th light beam to form an (n-1)th light beam; The (n-1)th reflective element receives the (n-1)th light beam and reflects the (n-1)th light beam to form an nth light beam; and The nth reflective element receives the nth light beam and reflects the nth light beam to the projection surface to project the image information to the projection surface.

42. The method of claim 40 or 41, wherein, The first reflective element and the second reflective element are configured to rotate within a rotation angle range less than or equal to 4°.

43. The method of claim 40 or 41, wherein, The first reflective element and the second reflective element are configured to be movable, wherein a distance ΔL2 between a center of the first reflective element and a center of the second reflective element on an optical axis satisfies: -0.5 mm≤ΔL2≤0.5 mm.

44. The method of claim 40 or 41, wherein, A distance L1 between a center of the image module and a center of the first reflective element on an optical axis, a distance L2 between the center of the first reflective element and a center of the second reflective element on the optical axis, and a total effective focal length F of the projection system satisfy: (L1+L2) / F≤4.

Images