Optical module and projection ray machine

Abstract

The invention discloses an optical module and a projection ray machine, the optical module comprises a light source assembly and a metal substrate, and the light source assembly emits a light beam along a first direction; at least one surface of the metal substrate is provided with a reflecting surface, the reflecting surface is used for changing the projection direction of the light beam from the first direction to a second direction different from the first direction, and the reflecting surface is a polished surface. According to the technical scheme, the effect of reflecting light can be achieved, and meanwhile the cost reduction requirement is met without the film coating or film pasting technology.

Description

Technical Field

[0001] This application relates to the field of projection technology, and particularly to an optical module and a projection optical engine. Background Art

[0002] In recent years, with the vigorous development of science and technology, projection technology has become increasingly mature, and projection devices have been gradually widely used in various scenarios and are increasingly favored by people. The projection optical engine integrates the light source, display chip, radiator, and optical path design of the projection device into a single integrated component.

[0003] In related technologies, in order to reduce the volume of the projection optical engine to improve the portability of the projector, a method of plating a metal film or attaching an optical reflective film on the substrate is adopted to reflect the internal light, so that the optical path in the projection optical engine can be folded and turned to reduce the volume of the projection optical engine. However, the reflection scheme using the above-mentioned coating or laminating process is complex and costly to manufacture, resulting in a high cost of the projection optical engine. Summary of the Invention

[0004] Embodiments of this application provide an optical module and a projection optical engine, which can play a role in reflecting light, and at the same time, do not require the process of coating or laminating to meet the cost reduction requirements.

[0005] In a first aspect, embodiments of this application provide an optical module, which includes:

[0006] A light source assembly that emits a light beam along a first direction; and

[0007] A metal substrate, at least one surface of the metal substrate is provided with a reflective surface, and the reflective surface is used to change the projection direction of the light beam from the first direction to a second direction different from the first direction, and the reflective surface is a polished surface.

[0008] In some embodiments, a heat dissipation structure is provided on a side of the metal substrate facing away from the reflective surface.

[0009] In some embodiments, the heat dissipation structure is a plurality of heat dissipation fins arranged at intervals;

[0010] The plurality of heat dissipation fins and the metal substrate are of an integral structure, and / or the distance between adjacent heat dissipation fins is greater than or equal to 3 millimeters and less than or equal to 6 millimeters.

[0011] In some embodiments, the optical module further includes a protective layer, and the protective layer is provided on the reflective surface.

[0012] In some embodiments, the thickness of the protective layer is greater than or equal to 1 nanometer and less than or equal to 10 nanometers;

[0013] And / or, the protective layer is a silicon dioxide layer.

[0014] In some embodiments, the light source assembly includes a light source, and a reflector cup, a first lens, a light valve, and a second lens sequentially arranged along the propagation direction of the emitted light of the light source;

[0015] The reflector cup is configured to converge and reflect the emitted light of the light source to the first lens, the first lens is configured to collimate the emitted light and direct it to the light valve, the light valve is configured to modulate the emitted light of the light source to form a light beam, and the second lens is configured to collimate the light beam, and the light beam is an image source light beam.

[0016] In some embodiments, the reflector cup has an accommodating cavity with both ends penetrating, and one end of the accommodating cavity is an incident port and the other end is an exit port. The incident port of the reflector cup is sleeved on the light source, the first lens is arranged on the exit port of the reflector cup, and the reflector cup reflects the emitted light of the light source to the first lens on the inner surface of the accommodating cavity;

[0017] The inner surface of the accommodating cavity of the reflector cup is a polished surface.

[0018] In some embodiments, the light source assembly further includes a polarizing member, and the polarizing member is disposed between the first lens and the light valve for reflecting a light beam having a polarization direction different from that of the light valve.

[0019] In some embodiments, the metal substrate is an aluminum substrate or a copper substrate;

[0020] And / or, the roughness Ra of the reflection surface < 0.05 micrometers.

[0021] In a second aspect, an embodiment of the present application provides a projection optical machine, and the projection optical machine includes a housing, a projection lens, and an optical module as described above;

[0022] The housing encloses to form an installation cavity, and the metal substrate, the light source assembly, and the projection lens are installed in the installation cavity. The projection lens is configured to receive the light beam reflected by the reflection surface of the metal substrate and project it to the outside of the housing;

[0023] Or, the housing is connected to the metal substrate and encloses to form an installation cavity, the light source assembly and the projection lens are installed in the installation cavity, the reflection surface of the metal substrate is arranged facing the inside of the installation cavity, and the projection lens is configured to receive the light beam reflected by the reflection surface of the metal substrate and project it to the outside of the housing;

[0024] Alternatively, the housing encloses to form an installation cavity. A part of the housing is configured as the metal substrate, and the inner wall surface of the housing forms the reflecting surface. The light source assembly and the projection lens are installed in the installation cavity, and the projection lens is configured to receive the light beam reflected by the reflecting surface of the metal substrate and project it outside the housing.

[0025] Based on the optical module and the projection optical machine of the embodiments of the present application, by polishing at least one surface of the metal substrate to form a reflecting surface, the light beam emitted by the light source assembly along the first direction can be changed to be emitted in a second direction different from the first direction. In this way, the light beam can be reflected without the processes of coating or laminating. This not only has low production costs and simple production processes to meet the cost reduction requirements, but also is convenient for further reducing the volume of the projection optical machine. Description of the Drawings

[0026] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0027] Figure 1 It is a schematic structural diagram of the optical module and the projection lens of the present application;

[0028] Figure 2 It is a schematic structural diagram of the metal substrate of the optical module of the present application.

[0029] Explanation of the reference numerals in the drawings:

[0030] 1. Optical module; 10. Light source assembly; 11. Light source; 12. Reflector cup; 121. Incident port; 122. Exit port; 13. First lens; 14. Light valve; 15. Second lens; 16. Polarizing element; 20. Metal substrate; 21. Reflecting surface; 22. Heat dissipation fins; 2. Projection lens.

[0031] The realization of the purpose, functional features, and advantages of the present application will be further described with reference to the embodiments and the drawings. Detailed Embodiments

[0032] To make the purpose, technical solutions, and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the drawings.

[0033] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0034] In the description of the present application, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. In addition, in the description of the present application, unless otherwise specified, "a plurality" means two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the preceding and following associated objects.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the description of this specification are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0036] In the related art, in order to reduce the volume of the projection optical machine to improve the portability of the projector, a method of plating a metal film or pasting an optical reflection film on the substrate is adopted to reflect the internal light, so that the optical path in the projection optical machine can be folded and turned to reduce the volume of the projection optical machine. However, the reflection scheme using the above-mentioned coating or film pasting process is complex and costly to manufacture, resulting in a high cost of the projection optical machine.

[0037] To solve the above problems, please refer to Figure 1 In a first aspect of the present application, a projection optical machine is proposed. In an embodiment of the present application, the projection optical machine includes a housing (not shown), a projection lens 2, and an optical module 1.

[0038] Among them, the outer shell can define the outline of the entire projection optical machine, and the main structure of the outer shell can be made of plastic. For example, suitable exemplary materials that can be used include but are not limited to hard plastics, such as polyethylene, polypropylene (PP), polyamide, etc. Of course, the main structure of the outer shell can also be made of metal, such as aluminum alloy, and the present application does not limit this. The projection lens 2 receives the light beam from the optical module 1, magnifies it, and projects it outside the outer shell to form a projection image. The projection lens 2 includes 4 spherical glass lenses, and it can also have other numbers of lenses. The lenses can be made of glass or optical plastic. If it is made of glass, it is generally a spherical glass lens. If it is made of plastic, it is generally an aspherical plastic lens. In this solution, the projection lens 2 uses 4 spherical glass lenses. Along the light propagation direction, the optical powers of the 4 lenses are positive, positive, negative, and positive respectively. The projection lens 2 adopts a 4-lens design. By reasonably arranging the positive and negative focal lengths, refractive indices, and Abbe numbers of the 4 lenses, the light can converge and diverge to different degrees when passing through the positive and negative lenses in turn, achieving a projection ratio of 1.2, which can meet the requirements of miniaturization and large screen of the projection optical machine, and at the same time can achieve high-definition imaging.

[0039] In order to both play a role in reflecting light to reduce the volume of the projection optical machine and meet the cost reduction requirements at the same time. In the second aspect of the present application, an optical module 1 is proposed. In the embodiments of the present application, please refer to Figure 1 and Figure 2 , the optical module 1 includes a light source component 10 and a metal substrate 20. The light source component 10 emits a light beam along the first direction. At least one surface of the metal substrate 20 is provided with a reflecting surface 21, and the reflecting surface 21 is used to change the projection direction of the light beam from the first direction to a second direction different from the first direction. The reflecting surface 21 is a polished surface.

[0040] Specifically, the outer shell and the metal substrate 20 can be one of the following three installation forms:

[0041] The first installation form is as follows: The outer shell encloses to form an installation cavity, and the metal substrate 20, the light source assembly 10, and the projection lens 2 are installed in the installation cavity. The projection lens 2 is used to receive the light beam reflected by the reflecting surface 21 of the metal substrate 20 and project it to the outside of the outer shell. In this method, the outline of the entire installation cavity is directly defined by the outer shell, and the outer outline of the outer shell can be roughly in the shape of a cuboid, a cube, or other prisms, which is convenient for overall moving and installation. The application does not limit the shape of the outer outline of the outer shell. The metal substrate 20, the light source assembly 10, and the projection lens 2 can be fixed to the inner wall of the outer shell by means of snap connection or screw connection, etc., so as to be accommodated in the installation cavity, so that the positions of the metal substrate 20, the projection lens 2, and the light source assembly 10 are stable relative to the inside of the outer shell, so as to improve the projection lens 2 can stably receive the light beam reflected by the reflecting surface 21 of the metal substrate 20 and project it to the outside of the outer shell, so as to ensure the stability of the optical path transmission and further improve the imaging. The above installation method can prevent the metal substrate 20 from being exposed outside the outer shell for a long time, reduce the corrosion of external water vapor, and extend the service life of the metal substrate 20.

[0042] The second installation form is as follows: The outer shell is connected to the metal substrate 20 and encloses to form an installation cavity. The light source assembly 10 and the projection lens 2 are installed in the installation cavity, and the reflecting surface 21 of the metal substrate 20 faces the inside of the installation cavity. The projection lens 2 is used to receive the light beam reflected by the reflecting surface 21 of the metal substrate 20 and project it to the outside of the outer shell. It can be understood that the outer shell is formed with an installation notch, and the outer shell and the metal substrate 20 can be fixed by means of snap connection, screw connection, welding, etc., so that the metal substrate 20 plugs and covers the installation notch, so as to enclose to form an installation cavity, and the light source assembly 10 and the projection lens 2 are installed in the installation cavity. In this way, the metal substrate 20 not only has the function of reflecting light beams, but also plays a role in protecting the components in the installation cavity, and makes the metal substrate 20 occupy less internal space of the outer shell, and further can reduce the volume of the projection optical machine. The above installation method is convenient to control the shape of the metal substrate 20 to adapt to different installation environments, so as to facilitate the replacement of the metal substrate 20 according to specific requirements in the later stage and improve the flexibility of the projection optical machine.

[0043] The third installation form is: the shell is enclosed to form an installation cavity, part of the shell is configured as a metal substrate 20, and the inner wall surface of the shell forms a reflective surface 21, the light source assembly 10 and the projection lens 2 are installed in the installation cavity, and the projection lens 2 is used to receive the light beam reflected by the reflective surface 21 of the metal substrate 20 and project it to the outside of the shell. In this way, on the basis of the shell directly defining the outline of the entire installation cavity, part or all of the material of the shell is made of metal material, so that the part forms the metal substrate 20, and the inner surface of the shell facing the installation cavity is polished to form the reflective surface 21, that is, the metal substrate 20 and the shell are an integrated structure. Therefore, the above-mentioned installation method saves the assembly process of the metal substrate 20 and the shell to improve the overall installation efficiency.

[0044] It should be noted that in the above three installation methods, a light exit area is formed on the housing, and the light exit area can be a through hole or made of a transparent material, so that the projection lens 2 can project a light beam to the outside of the housing through the light exit area.

[0045] The light source assembly 10 can emit light when connected to an external power source and emit a light beam in a first direction, and the reflective surface 21 of the metal substrate 20 is located in the light emitting direction of the light source assembly 10, so as to change the projection direction of the light beam from the first direction to a second direction different from the first direction. The metal substrate 20 can be tilted at 45° relative to the first direction, so that the angle between the extension line of the second direction of the reflected light beam and the extension line of the first direction can be set at a right angle, so as to facilitate the control of the light emitting direction of the reflected light beam, thereby facilitating the setting of the position of the projection lens 2 and improving the installation efficiency. Of course, the angle between the extension line of the first direction and the extension line of the second direction can also be set at other angles to adapt to projection light machines of different shapes and sizes.

[0046] The metal substrate 20 can be set as a flat plate to further reduce the size of the projection light machine. The metal substrate 20 can be polished by lathe CNC processing or manual polishing to form a reflective surface 21, and the reflective surface 21 is also set in a plane, so as to facilitate the control of the direction of the light beam. It should be noted that the metal substrate 20 can be polished on a single surface to form a reflective surface 21, so as to reduce the difficulty of processing. Of course, multiple surfaces of the metal substrate 20 can also be polished to form multiple reflective surfaces 21, so as to reduce the difficulty of aligning the reflective surface 21 of the metal substrate 20 with the light source assembly 10 during installation, thereby improving the installation efficiency. In addition, it should be noted that multiple metal substrates 20 can be set, so that the light beam can be folded and turned after being arranged according to specific settings.

[0047] Optionally, the metal substrate 20 can be an aluminum substrate or a copper substrate. In this way, not only can the cost be saved, but also the structural strength of the metal substrate 20 can be ensured. At the same time, the aluminum substrate or the copper substrate has high heat dissipation and high thermal conductivity performance, so as to dissipate the heat of the reflected light beam.

[0048] Optionally, the roughness Ra of the reflecting surface 21 is less than 0.05 microns. Among them, by defining that the roughness Ra of the reflecting surface 21 is less than or equal to 0.05 microns, the reflecting surface 21 is made smoother and has a higher reflectivity, so as to further increase the amount of light reflected by the reflecting surface 21, that is, increase the light projected onto the projection lens 2, and thus improve the imaging effect.

[0049] Based on the optical module 1 and the projection optical machine of the embodiment of the present application, by polishing at least one surface of the metal substrate 20 to form the reflecting surface 21, the light beam emitted by the light source component 10 along the first direction can be changed to be emitted in a second direction different from the first direction. In this way, the light beam can be reflected without the process of coating or laminating. Not only is the production cost low and the production process simple, meeting the cost reduction requirements, but also it is convenient to further reduce the volume of the projection optical machine.

[0050] Since the reflectivity of the metal substrate 20 is about 85%-90%, 10%-15% of the light energy is absorbed by the metal substrate 20, thus generating heat. Refer to Figure 1 and Figure 2 , in some structural forms, a heat dissipation structure is provided on the side of the metal substrate 20 facing away from the reflecting surface 21. Thereby, the heat generated by the absorption of the metal substrate 20 can be dissipated, the self-temperature of the metal substrate 20 when reflecting light can be reduced, the situation of high temperature points in the projection optical machine can be effectively reduced, and the thermal influence on the internal structure of the projection optical machine can be reduced. At the same time, the heat dissipation structure can also extend to the outside of the projection optical machine, so that the heat dissipation structure can also assist in dissipating the heat of the internal structure of the projection optical machine to the outside of the projection optical machine, thereby realizing the heat dissipation of the internal heat of the projection optical machine and improving the service life of the projection optical machine.

[0051] Furthermore, the heat dissipation structure is a plurality of heat dissipation fins 22 arranged at intervals. By arranging a plurality of heat dissipation fins 22 on the surface of the metal substrate 20 facing away from the reflecting surface 21, the surface of the metal substrate 20 facing away from the reflecting surface 21 and the surfaces of the respective heat dissipation fins 22 are heat dissipation surfaces, with a large heat dissipation area. There is a heat exchange groove between two adjacent heat dissipation fins 22, and the heat dissipation effect is good, so the heat dissipation efficiency is high. Moreover, the heat dissipation fins 22 can extend outside the projection optical machine, thereby significantly improving the heat dissipation effect of the closed-type projection optical machine and further improving the output luminous flux of the closed-type projection optical machine. The plurality of heat dissipation fins 22 and the metal substrate 20 are of an integral structure. For the convenience of processing in this embodiment, the metal substrate 20 and the heat dissipation fins 22 described in this embodiment can both be made of metal materials with good thermal conductivity such as cast aluminum or cast iron. During the processing, the metal substrate 20 and the heat dissipation fins 22 can be integrally cast by casting, which is not only beneficial to reducing the processing cost, but also the integrally formed metal substrate 20 and heat dissipation fins 22 can conduct heat more quickly to complete heat dissipation.

[0052] Optionally, the distance between adjacent heat dissipation fins 22 is greater than or equal to 3 mm and less than or equal to 6 mm. Among them, when the distance between adjacent heat dissipation fins 22 is less than 3 mm, the interval of the heat dissipation fins 22 at this time is small, which is not conducive to air circulation and the heat dissipation ability is weak. When the distance between adjacent heat dissipation fins 22 is greater than 6 mm, the interval of the heat dissipation fins 22 at this time is large, resulting in a small number of heat dissipation fins 22 and unable to effectively increase the heat dissipation area. Thus, by limiting the distance between adjacent heat dissipation fins 22 to be greater than or equal to 3 mm and less than or equal to 6 mm, such as 3 mm, 4 mm, 5 mm, 6 mm, etc., it can ensure the air circulation between adjacent heat dissipation fins 22, and at the same time increase the number of heat dissipation fins 22 arranged and improve the heat dissipation area. In addition, the height of the heat dissipation fins 22 is greater than or equal to 5 mm and less than or equal to 10 mm. In this way, the contact area between the fins and the air can be increased, and the heat dissipation efficiency can be improved. At the same time, it can also prevent the height of the heat dissipation fins 22 from being too large and affecting the assembly. Of course, in other embodiments, the heat dissipation structure can also be a microchannel heat exchanger or a semiconductor heat sink, etc.

[0053] Refer to Figure 1 , in some structural forms, the light source assembly 10 includes a light source 11 and a reflecting cup 12, a first lens 13, a light valve 14, and a second lens 15 arranged in sequence along the propagation direction of the emitted light of the light source 11. The reflecting cup 12 is used to converge and reflect the emitted light of the light source 11 to the first lens 13. The first lens 13 is used to collimate the emitted light and project it onto the light valve 14. The light valve 14 is used to modulate the emitted light of the light source 11 to form a light beam. The second lens 15 is used to collimate the light beam, and the light beam is an image source light beam.

[0054] Among them, the light source 11 can be a point light source, such as an LED light source and a laser light source. When the light source 11 is an LED light source, it has a wider color gamut, higher color saturation, and a long service life, which can reach tens of thousands of hours to reduce the maintenance frequency. The reflector 12 can be in the shape of a gradually tapered horn, and the cross-sectional area of the reflector 12 gradually increases along the direction from the light incident end to the light output end. In this way, the reflector 12 is used for condensing light, which can improve the efficiency of the light source assembly 10, reduce light loss, increase brightness, and at the same time can also reduce costs. Then, the first lens 13 collimates the emitted light and shoots it towards the light valve 14. The first lens 13 can be a Fresnel lens. Of course, in other embodiments, the first lens 13 can also be other devices with the same function, and is not limited thereto. The light valve 14 is a liquid crystal light valve 14, and the liquid crystal light valve 14 can modulate the emitted light of the light source 11 to generate an image source. Specifically, it can control the passing amount of different color lights according to the input signal to achieve the desired image. The second lens 15 can be the same as the first lens 13, which is a Fresnel lens, and only needs to collimate the light beam emitted from the light valve 14. In this way, through the cooperative setting of the above-mentioned multiple components, the light beam emitted by the light source assembly 10 towards the metal substrate 20 is an image source light beam, and then it is reflected by the metal substrate 20 to the projection lens 2, and finally projected and magnified by the projection lens 2 to form a projection screen.

[0055] Further, the reflector 12 has a receiving cavity that penetrates through both ends, and one end of the receiving cavity is an incident port 121, and the other end is an exit port 122. The incident port 121 of the reflector 12 is sleeved on the light source 11, and the first lens 13 is arranged on the exit port 122 of the reflector 12. The reflector 12 reflects the emitted light of the light source 11 to the first lens 13 on the inner surface of the receiving cavity. The inner surface of the receiving cavity of the reflector 12 is a polished surface.

[0056] Among them, the material of the reflector 12 is aluminum, and its inner wall surface is processed into a reflective mirror surface by a polishing process, and the specular reflectivity is 80% - 90%. In this way, the emitted light of the light source 11 can be reflected by the reflective mirror surface for aggregation, which can improve the efficiency of the light source assembly 10, reduce light loss, and increase brightness. Thus, a reflective effect can be formed without the process of coating or laminating, so as to meet the cost reduction requirements.

[0057] In addition, the length of the effective light-emitting surface of the light source 11 is 16 mm to 20 mm, and the width is 11 mm to 15 mm, so as to ensure the light output. The length of the incident port 121 of the reflector cup 12 is 17 mm to 21 mm, and the width is 12 mm to 16 mm. The length of the exit port 122 of the reflector cup 12 is 112 mm to 116 mm, and the width of the exit port 122 is 64 mm to 68 mm. It should be noted that the length of the incident port 121 and the exit port 122 of the reflector cup 12 corresponds to the length of the effective light-emitting surface of the light source 11, and the width of the incident port 121 and the exit port 122 of the reflector cup 12 corresponds to the width of the effective light-emitting surface of the light source 11. Similarly, the length of each subsequent component corresponds to the length of the effective light-emitting surface of the light source 11, and the width corresponds to the width of the effective light-emitting surface of the light source 11. The distance between the incident port 121 and the exit port 122 is 60 mm to 80 mm. Thus, the incident port 121 of the reflector cup 12 can just sleeve the effective light-emitting surface of the light source 11, while avoiding the reflector cup 12 occupying too large a volume. The lengths of the first lens 13 and the second lens 15 are 113 mm to 117 mm, the widths are 65 mm to 69 mm, and the thickness is 1.5 mm to 2.0 mm. The material is optical plastic (such as Poly Methyl MethAcrylate, PMMA). When set in this way, both the length and width of the first lens 13 are greater than the length and width of the exit port 122 of the reflector cup 12, so that the first lens 13 can completely cover the exit port 122 of the reflector cup 12, and then the light rays emitted from the exit port 122 will be collimated and homogenized by the first lens 13. Since the light rays are collimated and homogenized by the first lens 13, the light rays will be more concentrated, so that the size of the light valve 14 can be slightly smaller than that of the first lens 13, that is, the length of the light valve 14 can be 110 mm to 111 mm, and the width is 62 mm to 63 mm, so as to further save the internal space and meet the cost reduction requirement.

[0058] Referring to Figure 1 , optionally, the light source assembly 10 further includes a polarizing member 16, and the polarizing member 16 is disposed between the first lens 13 and the light valve 14 to reflect the light beam with a polarization direction different from that of the light valve 14.

[0059] Among them, the polarizing member 16 can be a polarizing beam splitting glass. When the light source 11 is an LED light source 11, since the light emitted by the LED light source 11 is natural light (unpolarized light), and the working principle of the light valve 14 is polarized light illumination. Assuming that the required is horizontal polarized light. Therefore, 50% of the light energy (vertical polarized light) emitted by the LED light source 11 is useless for the light valve 14. In order to prevent this part of the light energy from being absorbed by the light valve 14, resulting in an increase in its temperature and a reduction in its lifespan, or even high-temperature damage, the polarizing member 16 is used to reflect this part of the light energy, and the horizontal polarized light required by the light valve 14 will pass through the polarizing member 16 and illuminate it.

[0060] In some structural forms, the polarizing member 16 is composed of a glass substrate, an absorption-type polarizing film, and a reflection-type polarizing film. The absorption-type polarizing film and the reflection-type polarizing film are attached to the same side of the glass substrate, and the reflection-type polarizing film is on the outermost side. The side of the polarizing member 16 with the film layer faces the first lens 13. Alternatively, the absorption-type polarizing film and the reflection-type polarizing film are respectively attached to both sides of the glass substrate, and the side with the reflection-type polarizing film faces the first lens 13. In theory, the reflection-type polarizing film allows the horizontal polarized light required by the light valve 14 to pass through, and at the same time reflects the vertical polarized light. In fact, the reflectivity of the reflection-type polarizing film for the vertical polarized light is not 100%, and there is still a small part of the vertical polarized light that can pass through. Since the transmission axis of the absorption-type polarizing film is set in the same direction as the transmission axis of the reflection-type polarizing film, the absorption-type polarizing film will absorb this part of the transmitted vertical polarized light, thereby improving the polarization degree of the illumination beam and further improving the display contrast of the light valve 14.

[0061] In some structural forms, the optical module 1 further includes a protective layer (not shown), and the protective layer is provided on the reflection surface 21. Among them, the protective layer can be formed on the reflection surface 21 by deposition, or can also be adhered and pasted on the reflection surface 21. In this way, through the setting of the protective layer, the reflection surface 21 can be prevented from being scratched. Of course, in order to improve the protection effect, the protective layer can completely cover the reflection surface 21, and the protective layer is made of a light-transmitting material, which can fully protect the reflection surface 21 while avoiding affecting the light.

[0062] Furthermore, the thickness of the protective layer is greater than or equal to 1 micron and less than or equal to 10 microns. Among them, when the thickness of the protective layer is less than 1 micron, the thickness of the protective layer is relatively thin at this time, and the protection ability for the reflection surface 21 is weak. And when the thickness of the protective layer is greater than 10 microns, the thickness of the protective layer is relatively thick at this time, which easily affects the light passing amount, thereby affecting the reflection effect of the subsequent reflection surface 21. In this way, by limiting the thickness of the protective layer to be greater than or equal to 1 micron and less than or equal to 10 microns, such as 2 microns, 4 microns, 6 microns, 8 microns, etc., the protection effect can be ensured while reducing the influence on the light passing amount and improving the reflection effect of the reflection surface 21.

[0063] Optionally, the protective layer is a silicon dioxide layer. The protective layer is a silicon dioxide protective layer or other silicon oxide layer. In other embodiments, the protective layer may also be made of other materials, as long as it can sufficiently protect the reflecting surface 21 while avoiding affecting light.

[0064] In the drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present application, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and cannot be construed as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0065] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An optical module, used in a projection optical machine, It is characterized in that The optical module comprises: a light source assembly, the light source assembly emitting a light beam along a first direction; and A metal substrate, wherein at least one surface of the metal substrate is provided with a reflective surface, the reflective surface is used to change the projection direction of the light beam from the first direction to a second direction different from the first direction, and the reflective surface is a polished surface.

2. The optical module according to claim 1, It is characterized in that A heat dissipation structure is provided on a side of the metal substrate away from the reflective surface.

3. The optical module according to claim 2, It is characterized in that The heat dissipation structure is a plurality of heat dissipation fins arranged at intervals; The plurality of heat dissipation fins and the metal substrate are an integral structure, and / or a spacing between adjacent heat dissipation fins is greater than or equal to 3 mm and less than or equal to 6 mm.

4. The optical module according to claim 1, It is characterized in that The optical module further includes a protective layer, and the protective layer is arranged on the reflective surface.

5. The optical module according to claim 4, It is characterized in that The thickness of the protective layer is greater than or equal to 1 nanometer and less than or equal to 10 nanometers; And / or, the protective layer is a silicon dioxide layer.

6. The optical module according to claim 1, It is characterized in that The light source assembly comprises a light source, and a reflective cup, a first lens, a light valve and a second lens which are sequentially arranged along the propagation direction of the emitted light of the light source; The reflective cup is used to converge and reflect the output light of the light source to the first lens, the first lens is used to collimate the output light and direct it to the light valve, the light valve is used to modulate the output light of the light source to form the light beam, the second lens is used to collimate the light beam, and the light beam is an image source light beam.

7. The optical module according to claim 6, It is characterized in that The reflective cup has a accommodating cavity with two ends connected, and one end of the accommodating cavity is an incident port, and the other end is an exit port. The incident port of the reflective cup is sleeved on the light source, and the first lens is arranged on the exit port of the reflective cup. The reflective cup reflects the exit light of the light source to the first lens on the inner surface of the accommodating cavity. The inner surface of the reflective cup in the accommodating cavity is a polished surface.

8. The optical module according to claim 6, It is characterized in that The light source assembly further includes a polarizing element, which is disposed between the first lens and the light valve and is used to reflect a light beam having a polarization direction different from that of the light valve.

9. The optical module according to any one of claims 1 to 8, It is characterized in that The metal substrate is an aluminum substrate or a copper substrate; And / or, the roughness of the reflecting surface Ra is less than 0.05 micrometers.

10. A projection light machine, It is characterized in that The projection optical machine comprises a housing, a projection lens and an optical module according to any one of claims 1 to 9; The housing encloses a mounting cavity, the metal substrate, the light source assembly and the projection lens are mounted in the mounting cavity, and the projection lens is used to receive the light beam reflected by the reflective surface of the metal substrate and project it to the outside of the housing; Alternatively, the housing is connected to the metal substrate and encloses to form an installation cavity, the light source assembly and the projection lens are installed in the installation cavity, the reflective surface of the metal substrate is arranged facing the inside of the installation cavity, and the projection lens is configured to receive the light beam reflected by the reflective surface of the metal substrate and project it outside the housing; Alternatively, the housing encloses to form an installation cavity, a part of the housing is configured as the metal substrate, and the inner wall surface of the housing forms the reflective surface, the light source assembly and the projection lens are installed in the installation cavity, and the projection lens is configured to receive the light beam reflected by the reflective surface of the metal substrate and project it outside the housing.

Images