Optical engine and projection device
By installing light blocking parts in the optical engine of the micro projector to block stray light from irradiating the housing, the problem of aging and deformation of the housing of the optical engine of the micro projector is solved, and the light resistance and heat resistance of the equipment is improved.
Patent Information
- Application Number
- CN202420972071.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-07
- Publication Date
- 2025-03-14
- Estimated Expiration
- 2034-05-07
AI Technical Summary
The optical engine housing of the micro projector aging and deforming due to strong light, resulting in the normal operation and long life of the projector.
An optical engine is designed, which is mounted on the housing using a light blocking member, located on the stray light outgoing path of the combined light prism, preventing stray light from irradiating to the housing.
It effectively avoids stray light directly irradiating to the shell, prevents the shell from aging and deforming due to heat, and improves the light and heat resistance of the optical engine.
Smart Images
Figure CN222618945U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to an optical engine and a projection device, in particular to an optical engine and a projection device with a lightweight shell. Background Art
[0002] Micro projectors are portable and low-cost. Although the projection screen size and brightness cannot be compared with general projectors, they are very attractive to business users who need mobile projection. As digital light processing (DLP) projectors become more and more miniaturized and closer to general consumer groups, the micro projector market is becoming more and more popular. Micro projectors are getting smaller and smaller. At the same time, in order to be small and lightweight, the material selection of their optical engine housings has gradually changed to lightweight materials such as plastic.
[0003] However, in the optical path design of the micro-projector, due to the refraction effect of the light-combining prism in the optical path, some strong light will not be transmitted to the lens for projection, but will remain in the cavity of the optical engine shell. At this time, the strong light will cause the shell made of plastic and other materials to age and deform, which will affect the normal operation of the projector and may even damage the projector.
[0004] Therefore, how to improve the light and heat resistance of the micro-projector optical engine has become a new research topic. Utility Model Content
[0005] The utility model aims to provide an optical engine and a projection device with a lightweight housing, so as to prevent the housing from being directly irradiated by strong light and thus causing aging and deformation.
[0006] Based on the above objectives, the utility model provides an optical engine, including:
[0007] A housing having a light outlet;
[0008] A light-combining prism is mounted on the housing, and is used to project effective image light out from the light outlet; and
[0009] A light blocking member, mounted on the housing and located on a light exit path of stray light from the light combining prism;
[0010] Wherein, the light blocking member is used to block the stray light from irradiating the housing; the light blocking member has a first opening, and the first opening corresponds to the light outlet.
[0011] Preferably, there is a gap between at least a portion of the light blocking member and the housing.
[0012] Preferably, the surface of the light blocking member has an anti-reflection layer.
[0013] Preferably, the light blocking member has a frame portion and an extension portion;
[0014] The frame is fixed to the shell, and the first opening is located at the frame to expose the light outlet of the shell; the extension is also used for heat dissipation.
[0015] Further preferably, the extension portion is coplanar with the frame portion;
[0016] Alternatively, the extension portion is bent relative to the frame portion.
[0017] Further preferably, the extension portion is a plane;
[0018] Alternatively, the extension is wavy;
[0019] Alternatively, the extension is a fin.
[0020] Preferably, the frame is inclined to a propagation direction of the stray light of the light from the light-combining prism, so that the stray light is not reflected by the frame toward the light-combining prism.
[0021] Preferably, the light blocking member is fixed to the housing by means of screws or hooks, wherein the screws or hooks are disposed at a position away from an irradiation area of the stray light.
[0022] Preferably, the light blocking member is embedded in the housing.
[0023] Preferably, the housing is provided with a positioning column, and the light blocking member is correspondingly provided with a positioning groove.
[0024] Preferably, the housing has a plurality of positioning protrusions, and different parts of the light-combining prism are respectively in contact with the plurality of positioning protrusions.
[0025] Based on the above objectives, the utility model further provides a projection device, comprising:
[0026] chassis;
[0027] The optical engine is installed in the housing; and
[0028] A lens is installed in the housing and is located on the light output path of the optical engine.
[0029] Compared with the prior art, the optical engine and projection device provided by the utility model include a housing, a light-combining prism, and a light-blocking member, wherein the light-blocking member is installed on the housing and is located on the light-exiting path of the stray light of the light-combining prism. The light-blocking member is used to block the stray light from irradiating the housing; the light-blocking member has a first opening, and the first opening corresponds to the light-exiting port of the housing. By using the light-blocking member to block the stray light from irradiating the housing, the stray light can be prevented from directly irradiating the housing, thereby preventing the housing from aging and deforming due to heat. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 It is a partial structural schematic diagram of a projection device in one embodiment of the utility model;
[0031] Figure 2 It is a schematic diagram of a partial explosion structure of a projection device in one embodiment of the utility model;
[0032] Figure 3 It is a schematic diagram of a partial structure of a projection device in one embodiment of the utility model at another viewing angle;
[0033] Figure 4 for Figure 1 Schematic diagram of the cross-sectional structure at AA in the middle;
[0034] Figure 5 It is a schematic diagram of the three-dimensional structure of a light blocking member in an embodiment of the utility model. DETAILED DESCRIPTION
[0035] In order to provide a further understanding of the purpose, structure, features, and functions of the present invention, the present invention is described in detail below with reference to the embodiments.
[0036] Certain words are used in the specification and claims to refer to specific components. Those with ordinary knowledge in the field should understand that manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but rather use differences in components' functions as the criteria for distinction. The term "including" mentioned throughout the specification and claims is an open-ended term and should be interpreted as "including but not limited to".
[0037] See also Figures 1 to 4 The projection device provided by the utility model includes a housing (not shown in the figure), an optical engine 100 and a lens 200. The optical engine 100 and the lens 200 are respectively installed in the housing, and the lens 200 is located on the light output path of the optical engine 100. In another embodiment, the lens 200 can also be directly installed on the housing 10 of the optical engine 100. In other words, the optical engine 100 can also include the lens 200, but the utility model is not limited thereto.
[0038] The optical engine 100 includes a housing 10, a light source (not shown in the figure) and a light-combining prism 21, wherein the housing 10 is, for example, a plastic housing 10, or is made of other lightweight materials; the light source is, for example, a laser light source, etc. The light source and the light-combining prism 21 are installed in the housing 10, and the housing 10 has a light outlet. The light emitted by the light source is first transmitted to the light-combining prism 21, and the light-combining prism 21 cooperates with the spatial light modulator to form effective image light. The light-combining prism 21 is also used to project the effective image light from the light outlet, and then further project it through the lens 200. In a preferred embodiment, as Figure 2 and Figure 3 As shown, the housing 10 has a plurality of positioning protrusions 12 , and different parts of the light-combining prism 21 are respectively in contact with the plurality of positioning protrusions 12 , so that the light-combining prism 21 is more stably installed in the housing 10 .
[0039] In the present embodiment, the optical engine 100 further includes a light blocking member 30, which is mounted on the housing 21 and is located on the light exit path of the stray light of the light combining prism 21, wherein the stray light is generated by defects of the light combining prism 21 and / or the front optical path, or the stray light can also be waste light generated by the spatial light modulator (e.g., DMD). In the present embodiment, the light blocking member 30 is mounted on the housing 10 on the light exit side of the light combining prism 21. The light blocking member 30 is used to block the stray light from irradiating the housing 10, wherein the light blocking member 30 is, for example, a metal member 30 made of heat-resistant materials such as titanium alloy, carbon steel, stainless steel, and aluminum; the light blocking member 30 has a first opening 30a, which corresponds to the light exit port of the housing 10, and the effective image light passes through the first opening 30a of the light blocking member 30 and the light exit port of the housing 21 in sequence, and then is projected out through the lens 200. Furthermore, the optical engine 100 further includes a spatial light modulator (not shown in the figure), which is disposed adjacent to the light combining prism 21 and is located on the propagation path of the light emitted by the light source, and the spatial light modulator cooperates with the light combining prism 21 to form the effective image light. The spatial light modulator is specifically, for example, a light transmission type spatial light modulator (such as LCD) or a light reflection type spatial light modulator (such as DLP, DMD or LCOS), and those skilled in the art can design corresponding optical path structures according to different types of spatial light modulators, which will not be described in detail here.
[0040] In a preferred embodiment, if Figure 4 and Figure 5As shown, the light blocking member 30 has a frame 301, which is fixed to the housing 10, and the first opening 30a is located in the frame 301 to expose the light outlet of the housing 10, that is, the light from the light-combining prism 21 will only irradiate the lens 200 and the light blocking member 30, and will not directly irradiate the housing 10. The light blocking member 30 (frame 301) plays a role in blocking the stray light from the light-combining prism 21 from irradiating the housing 10, preventing the energy of the light from gathering on the lightweight housing 10, and further preventing the housing 10 from being deformed by heat. Preferably, the frame 301 is inclined at a specific angle to the propagation direction of the stray light from the light-combining prism 21, so that the stray light will not be reflected by the frame 301 back to the light prism 21, preventing the reflected stray light from affecting the outgoing projected image, such as introducing ghost images, light spots, etc. It should be noted that the specific angle is designed according to the specific structure of the optical path, which is a design that can be implemented by those skilled in the art according to actual conditions, and will not be repeated here.
[0041] In a preferred embodiment, the light blocking member 30 further comprises an extension portion 302 connected to the frame portion 301, and the extension portion 302 is used to increase the surface area of the light blocking member 30, thereby increasing the light blocking area of the light blocking member 30. For example, the extension portion 302 is a plane 302 coplanar with the frame portion 301; or Figure 5 As shown, the extension portion 302 can also be bent relative to the frame portion 301 to further block the light reflected from the light-combining prism 21 and the frame portion 301 to prevent it from irradiating other positions of the housing 10. At the same time, the extension portion 302 increases the surface area of the light blocking member 30, improves the heat dissipation area, and can further improve the heat dissipation performance of the optical engine 100. In a preferred embodiment, the extension portion can also be designed to be wavy (not shown in the figure) or in a fin style (not shown in the figure). Preferably, the light blocking member 30 can have a plurality of extension portions (not shown in the figure), and the plurality of extension portions can extend in a plurality of directions relative to the frame portion 301, for example, the light blocking member 30 can have two extension portions, and the two extension portions extend in two opposite directions relative to the frame portion 301, respectively, but the utility model is not limited thereto.
[0042] In a preferred embodiment, the surface of the light blocking member 30 has an anti-reflection layer for reducing the reflection of the light from the light combining prism 21 by the light blocking member 30 (e.g., the frame 31). For example, the anti-reflection layer is an organic polystyrene layer or a polymethyl methacrylate layer; or, an inorganic metal oxide layer (e.g., magnesium oxide, aluminum oxide, etc.), a silicon oxide layer, etc., can be obtained by anodizing; or, the surface of the light blocking member 30 can be blackened, etc., but the present invention is not limited thereto. Among them, the organic anti-reflection layer and the blackening treatment reduce the reflection of light by absorbing light; the inorganic anti-reflection layer does not absorb light, and it moves the phase of part of the light so that the part of the light whose phase is moved interferes with another part of the light, thereby reducing the reflection of light. In other embodiments, the extension portion 302 is designed to have a surface structure or shape that can absorb excess light. For example, the light blocking member 30 can be surface etched / velvet treated to form an anti-reflective surface structure, so that the light is reflected multiple times inside the anti-reflective surface structure, thereby attenuating the energy of the light.
[0043] In a preferred embodiment, if Figures 1 to 3 As shown, the light blocking member 30 can be fixed to the housing 10 by screws; or, the light blocking member 30 can also be fixed to the housing 10 by hooks. Preferably, the screw or hook is set at a position away from the irradiation area of the light from the light-combining prism 21 to prevent the heat of the light from being conducted to the screw or the hook. In the above-mentioned embodiment, the light blocking member 30 can also be provided with an opening near the locking hole or the hook. The opening can be provided around the locking hole or the hook, or can be provided between the main irradiation area of the stray light and the locking hole or the hook, so as to extend the heat conduction path and further reduce the heat conducted to the housing 10 through the connecting parts such as the screw or the hook. In other embodiments, the screw or the hook can also be made of materials with low thermal conductivity such as titanium alloy, carbon steel, stainless steel, aluminum, etc., to reduce the heat conduction from the screw or the hook to the housing 10.
[0044] In another embodiment, the light blocking member 30 may also be embedded in the housing 10 , so that the light blocking member 30 and the housing 10 are integrally formed, which can reduce the installation steps of the light blocking member 30 and further reduce the manufacturing cost of the product.
[0045] Preferably, there is a gap between at least part of the light shielding member 30 and the housing 10, that is, the light shielding member 30 is not closely connected to the housing 10, and the air between the light shielding member 30 and the housing 10 plays a role of heat insulation, which improves the heat dissipation efficiency of the light shielding member 30 and reduces the heat conducted to the housing 10 by the light shielding member 30. For example, a gasket (not shown in the figure, for example, the screw or the hook can be inserted into the gasket to fix the gasket) can be provided between the light shielding member 30 and the housing 10, so that the light shielding member 30 and the housing 10 are separated by the gasket, but the utility model is not limited thereto. The gasket is made of a heat-insulating material such as glass fiber, asbestos, etc., or the gasket can also be a structure such as a vacuum plate that reduces the heat conduction efficiency, but the utility model is not limited thereto. Preferably, the light shielding member 30 can also be thermally coupled to the external heat dissipation component of the spatial light modulator (such as DLP, DMD, LCOS or LCD) or the light source to accelerate the heat dissipation efficiency of the light shielding member 30.
[0046] In a preferred embodiment, the housing 10 has a positioning column 11, and the light blocking member 30 has a corresponding positioning groove 31, which is used to pre-position the installation position of the light blocking member 30 on the housing 10. In this embodiment, the positioning groove 31 is first positioned on the positioning column 11, and after the position of the light blocking member 30 is positioned, the light blocking member 30 is locked and fixed to the housing 10 by screws. Preferably, there are at least two pairs of positioning columns 11 and positioning grooves 31, that is, there are at least two positioning columns 11 on the housing 10, and at least two positioning grooves 31 are correspondingly opened on the light blocking member 30, wherein the size of the positioning groove 31 in at least one pair of positioning columns 11 and positioning grooves 31 is larger than the cross-sectional area of the positioning column 11, at this time, the positioning column 11 can move in the positioning groove 31 with a larger size, and then used to fine-tune the position of the light blocking member 30; at the same time, the above-mentioned light blocking member 30 can also match the tolerance between parts or be used for housings 10 of different models, so that the light blocking member 30 has stronger universality.
[0047] In summary, the optical engine and projection device provided by the utility model include a housing, a light-combining prism, and a light-blocking member, wherein the light-blocking member is installed on the housing and is located on the light-exit path of the stray light of the light-combining prism. The light-blocking member is used to block the stray light from irradiating the housing; the light-blocking member has a first opening, and the first opening corresponds to the light-exit port of the housing. By using the light-blocking member to block the stray light from irradiating the housing, the stray light can be prevented from directly irradiating the housing, thereby preventing the housing from aging and deforming due to heat.
[0048] The present invention has been described by the above-mentioned relevant embodiments, however, the above-mentioned embodiments are only examples for implementing the present invention. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, any changes and modifications made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.
Claims
1. An optical engine, characterized in that: include: A housing having a light outlet; A light-combining prism is installed on the housing, and is used to project effective image light out from the light outlet; as well as A light blocking member, mounted on the housing and located on a light exit path of stray light from the light combining prism; Wherein, the light blocking member is used to block the stray light from irradiating the housing; The light blocking member has a first opening, and the first opening corresponds to the light exit.
2. The optical engine according to claim 1, characterized in that: A gap is formed between at least a portion of the light blocking member and the housing.
3. The optical engine according to claim 1, characterized in that: The surface of the light blocking member has an anti-reflection layer.
4. The optical engine according to claim 1, characterized in that: The light blocking member comprises a frame portion and an extension portion; The frame is fixed to the shell, and the first opening is located at the frame to expose the light outlet of the shell; the extension is also used for heat dissipation.
5. The optical engine according to claim 4, characterized in that: The extension portion is coplanar with the frame portion; Alternatively, the extension portion is bent relative to the frame portion.
6. The optical engine according to claim 4, characterized in that: The extension portion is a plane; Alternatively, the extension is wavy; Alternatively, the extension is a fin.
7. The optical engine according to claim 4, characterized in that: The frame portion is inclined to a propagation direction of the stray light from the light-combining prism, so that the stray light is not reflected by the frame portion toward the light-combining prism.
8. The optical engine according to claim 1, characterized in that: The light shielding member is fixed to the housing by means of screws or hooks, wherein the screws or hooks are arranged at positions far away from the irradiation area of the stray light.
9. The optical engine according to claim 1, characterized in that: The light blocking component is embedded in the housing.
10. A projection device, characterized in that: include: chassis; An optical engine as claimed in any one of claims 1 to 9, mounted in the housing; as well as A lens is installed in the housing and is located on the light output path of the optical engine.