Projection device
By designing a projection device including lighting module, multiplexed lens and light modulator, the problem of PBS prism occupying space is solved, and the compact structure and miniaturization design of the AR device are realized.
Patent Information
- Application Number
- CN202311016685.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-10
- Publication Date
- 2025-02-25
AI Technical Summary
In existing optical machine systems, PBS prisms occupy a large space and it is difficult to achieve the miniaturization of AR equipment.
A projection device is designed, including an illumination module, a multiplexed lens and a light modulator. The multiplexed lens converts the first light into a second light with a polarization state in the first polarization state, and converts the second light into a third light through a light modulator, and the polarization state of the third light is a second polarization state. The multiplexed lens is used to transmit the third light at the same time to achieve projection of the image.
By using multiplexing lenses to meet the pre-illumination and image projection requirements of the light modulator, the use of additional PBS prisms is avoided, making the projection device more compact and supporting the miniaturized design of AR devices.
Smart Images
Figure CN119511531A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of optical imaging technology, and more specifically, to a projection device. Background Art
[0002] With the rapid development of augmented reality (AR) display technology, head-mounted AR devices (such as smart glasses) have become a hot research and development target. In AR devices, the optical-mechanical system is one of the important components of AR devices.
[0003] The optomechanical system may generally include a display chip and a lens group, wherein the display chip is used to generate a projection image, and the display chip requires an additional light source to provide illumination light when generating the projection image. For example, in an optomechanical system using a liquid crystal on silicon (LCOS) chip as a display chip, linearly polarized light needs to be provided as illumination light.
[0004] The lens group plays a role in transmitting light. In conventional optical-mechanical systems that use LCOS chips as display chips, a polarizing beam splitter (PBS) prism is usually used in the back focus part of the lens group to separate the light of a specified polarization state in the illumination light. However, the PBS prism will occupy a certain space in the optical-mechanical system, making it difficult to achieve a miniaturized design of AR devices. Summary of the invention
[0005] An embodiment of the present application provides a projection device.
[0006] According to the first aspect of the present application, an embodiment of the present application provides a projection device, which includes an illumination module, a multiplexing lens, and an optical modulator. The illumination module is used to generate a first light. The multiplexing lens is arranged on the optical path where the first light is located, and is used to convert the first light into a second light, and the polarization state of the second light is a first polarization state. The optical modulator is arranged on the optical path where the second light is located, and is used to convert the second light into a third light, and emit the third light to the multiplexing lens; the polarization state of the third light is a second polarization state, and the second polarization state is different from the first polarization state. The multiplexing lens is also used to transmit the third light.
[0007] According to the second aspect of the present application, an embodiment of the present application further provides a projection device, which includes the above-mentioned projection apparatus.
[0008] The embodiment of the present application provides a projection device, which includes an illumination module, a multiplexing lens, and an optical modulator. On the one hand, the multiplexing lens can convert a first light into a second light whose polarization state is a first polarization state, so that the second light meets the illumination requirements of the optical modulator. Therefore, the optical modulator in the present application is a display chip (e.g., an LCOS chip) that requires polarized light as illumination light. On the other hand, the light carrying an image generated by the optical modulator (i.e., the third light) is transmitted through the multiplexing lens, so that the multiplexing lens can be used to project an image.
[0009] The multiplexed lens in the projection device provided in the present application has the functions of satisfying both the front lighting of the light modulator and the image projection. Therefore, there is no need to set up an additional PBS prism in the projection device, which can make the overall structure of the projection device more compact, thereby facilitating the miniaturization design of the projection device equipped with the projection device. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.
[0011] Figure 1 It is a schematic diagram of the structure of the projection device provided in an embodiment of the present application.
[0012] Figure 2 yes Figure 1 A structural schematic diagram of a projection device.
[0013] Figure 3 This is a schematic diagram of the positions of the lighting module and the optical waveguide provided in an embodiment of the present application.
[0014] Figure 4 This is another schematic diagram of the positions of the lighting module and the optical waveguide provided in the embodiment of the present application.
[0015] Figure 5 It is a schematic diagram of the structure of the collection module and the uniform light module provided in the embodiment of the present application.
[0016] Figure 6 yes Figure 2 Schematic diagram of the structure of the multiplexing lens.
[0017] Figure 7 yes Figure 2 Schematic cross-section of the multiplexing lens.
[0018] Figure 8 yes Figure 1Another structural schematic diagram of the projection device. DETAILED DESCRIPTION
[0019] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.
[0020] See also Figure 1 , an embodiment of the present application provides a projection device 100 and a projection equipment 200 equipped with the projection device 100. The projection device 200 may include the above-mentioned projection device 100 and a housing 201. Among them, the housing 201 plays a role in fixing and protecting the projection device 100. The projection device 100 can be used to generate and transmit light carrying an image. When a user wears the projection device 200, the above-mentioned light carrying the image can be incident on the user's eyes. Specifically, the projection device 200 can be an AR device (for example, AR glasses, AR head display, etc.).
[0021] See also Figure 2 , the projection device 100 in this embodiment may include an illumination module 10, a multiplexing lens 20 and an optical modulator 30. The illumination module 10 is used to generate a first light ray L1. The multiplexing lens 20 is arranged on the optical path where the first light ray L1 is located, and is used to convert the first light ray L1 into a second light ray L2, and the polarization state of the second light ray L2 is a first polarization state. The optical modulator 30 is arranged on the optical path where the second light ray L2 is located, and is used to convert the second light ray L2 into a third light ray L3, and transmit the third light ray L3 to the multiplexing lens 20, and the polarization state of the third light ray L3 is a second polarization state, and the second polarization state is different from the first polarization state. The multiplexing lens 20 is also used to transmit the third light ray L3. It should be noted here that the above-mentioned first light ray L1 may be a mixed light (for example, non-polarized Lambertian light) containing P polarized light and S polarized light, and the first light ray L1 will be converted into a second light ray L2 having only a single polarization state (that is, the first polarization state) after passing through the multiplexing lens 20. For example, a polarizing film may be provided on the surface of the multiplexing lens 20, which allows only light of a specified polarization state to be transmitted or reflected, so as to separate the second light L2 from the first light L1, thereby achieving the effect of converting the light from a mixed polarization state to a single polarization state.
[0022] On the one hand, the multiplexing lens 20 in this embodiment can convert the first light L1 into the second light L2 whose polarization state is the first polarization state, so that the second light L2 meets the illumination requirements of the light modulator 30. Therefore, the light modulator 30 in this application can be a display chip (for example, an LCOS chip) that requires polarized light as illumination light. On the other hand, the light carrying the image generated by the light modulator 30 (that is, the third light L3) is transmitted through the multiplexing lens 20, so that the multiplexing lens 20 can be used for projecting the image.
[0023] The multiplexing lens 20 in the projection device 100 provided in the present application has the functions of satisfying both the front lighting of the light modulator 30 and the image projection. Therefore, there is no need to set up an additional PBS prism in the projection device 100, which can make the overall structure of the projection device 100 more compact, thereby facilitating the miniaturization design of the projection equipment 200 equipped with the projection device 100.
[0024] The various components in the projection device 100 are introduced below.
[0025] In this embodiment, the illumination module 10 is used to generate a first light L1, wherein the first light L1 refers to a mixed light including P polarized light and S polarized light. Specifically, the illumination module 10 may be an LED light source, a laser light source, or the like.
[0026] In some possible embodiments, the illumination module 10 may include a plurality of illumination units 120, and the plurality of illumination units 120 are arranged at intervals on a side of the multiplexing lens 20 away from the light modulator 30. By providing a plurality of illumination units 120, the illumination module 10 may improve the energy efficiency and uniformity of light, so as to enhance the imaging brightness of the projection device 100.
[0027] Specifically, the plurality of lighting units 120 may be arranged at intervals along a preset direction, or may be arranged at intervals in an M*N rectangular array, or may be arranged at intervals in a ring shape on a designated plane, wherein the designated plane is substantially perpendicular to the emission direction of the first light beam L1. The number of lighting units 120 may be 3, 6, 9, etc., and the number and arrangement of the lighting units 120 are not specifically limited in this embodiment.
[0028] Here, the lighting module 10 is taken as an example of an LED light source, and the lighting unit 120 may be an LED lamp bead. Specifically, the plurality of lighting units 120 may include LED lamp beads of different colors. Figure 3The lighting module 10 includes two groups of LED lamp beads, which are symmetrically arranged to ensure that the first light L1 can be more uniform. Specifically, each group of LED lamp beads includes green LED lamp beads, red LED lamp beads and blue LED lamp beads, wherein the green LED lamp beads, the red LED lamp beads and the blue LED lamp beads are spaced apart from each other. Therefore, Figure 3 The lighting module 10 shown includes six lighting units 120. Figure 4 , multiple lighting units 120 can be arranged in a ring shape with uniform intervals, wherein green LED lamp beads, red LED lamp beads and blue LED lamp beads can be arranged alternately and cyclically to improve the uniformity of the first light L1.
[0029] In this embodiment, the projection device 100 may further include a collecting module 12 and a light homogenizing module 14, wherein the collecting module 12 and the light homogenizing module 14 are sequentially arranged between the illumination module 10 and the multiplexing lens 20 and located on the optical path where the first light L1 is located.
[0030] See also Figure 5 The collection module 12 is arranged on the optical path where the first light L1 is located, and is located between the illumination module 10 and the multiplexing lens 20, and is used to collect the first light L1 to improve the utilization efficiency of the first light L1. The collection module 12 may include a first collection lens 121 and a second collection lens 123, and the first collection lens 121 and the second collection lens 123 are arranged in sequence along the optical path where the first light L1 is located to improve the collection efficiency of the first light L1. Specifically, the first collection lens 121 and the second collection lens 123 may be convex lenses respectively.
[0031] The light homogenization module 14 is arranged on the optical path where the first light L1 is located, and is located between the collection module 12 and the multiplexing lens 20, and is used to homogenize the first light L1, so that the first light L1 incident on the multiplexing lens 20 is more uniform. In the case where the illumination module 10 is a laser light source, the first light L1 is a laser, and the light homogenization module 14 can also eliminate the speckle in the laser to a certain extent, so as to improve the imaging quality of the projection device 100. Specifically, the light homogenization module 14 can be a fly-eye lens, a light homogenization rod, and the like.
[0032] In this embodiment, the optical modulator 30 is arranged on the optical path where the second light L2 is located, and is used to convert the second light L2 emitted through the multiplexing lens 20 into a third light L3, and emit the third light L3 to the multiplexing lens 20. Among them, the polarization state of the second light L2 is the first polarization state, and the polarization state of the third light L3 is the second polarization state, and the second polarization state is different from the first polarization state. It should be noted here that the "first polarization state" and the "second polarization state" in this embodiment are both linear polarization states. Therefore, the optical modulator 30 in this embodiment needs to use linear polarized light as illumination light. Specifically, the first polarization state and the second polarization state can be orthogonal polarization states to each other. For example, the first polarization state can be an S polarization state, and the second polarization state can be a P polarization state; or, the first polarization state can be a P polarization state, and the second polarization state can be an S polarization state.
[0033] In some possible embodiments, the light modulator 30 may be a liquid crystal on silicon (LCOS) chip, for example, a reflective LCOS chip. When the second light L2 is incident on the LCOS chip, it will be reflected by the LCOS chip and converted into a third light L3 in an orthogonal polarization state. At the same time, the third light L3 also carries an image to be projected. Specifically, the LCOS chip is an optical element that combines liquid crystal and silicon chip technology. It can input electrical signals to the semiconductor chip through tiny interconnecting leads, and then drive the liquid crystal array to change the pixel state to achieve image modulation. Compared with other display technologies, the LCOS chip has the advantages of high contrast, high resolution, fast response and low power consumption. Therefore, the projection device 100 in this embodiment can improve the imaging quality of the projection device 200 by adopting the LCOS chip.
[0034] In this embodiment, the multiplexing lens 20 is roughly circular, and is disposed on the optical path where the first light L1 is located, and is used to convert the first light L1 into the second light L2. In addition, the multiplexing lens 20 is also disposed on the optical path where the third light L3 is located, and is also used to transmit the third light L3. Therefore, the multiplexing lens 20 provided in the present application has the functions of satisfying the front lighting of the light modulator 30 and the image projection, so that there is no need to set an additional PBS prism in the projection device 100, which can make the overall structure of the projection device 100 more compact, and thus facilitate the miniaturization design of the projection device 200 equipped with the projection device 100.
[0035] Please refer again Figure 2, the multiplexing lens 20 may be provided with an incident area 210 and an exit area 220. The incident area 210 and the exit area 220 are arranged on the same side of the multiplexing lens 20, the first light L1 is incident through the incident area 210, and the third light L3 is emitted through the exit area 220. Therefore, the incident area 210 and the exit area 220 are both located on the side of the multiplexing lens 20 facing the illumination module 10.
[0036] Specifically, the multiplexing lens 20 may include a first functional portion 240 and a second functional portion 250, the second functional portion 250 and the first functional portion 240 are adjacent, and the curvature radius of the surface where the second functional portion 250 and the first functional portion 240 are connected is different, so that the first light L1 and the third light L3 can propagate in the specified direction in the multiplexing lens 20. It should be noted here that "the second functional portion 250 and the first functional portion 240 are adjacent" should be understood as the surfaces of the two smoothly transitioning to each other at the adjacent position, such as the continuous gap is less than the specified value, or the two are located in the same plane, or the curved surfaces defined by the two are continuous, etc.; or it can be understood that the two together form a specific appearance contour, such as forming a step structure, an angle structure, a curved surface structure, etc. In addition, since the curvature radii of the surfaces connecting the second functional portion 250 and the first functional portion 240 in this embodiment are different, the optical path of the second light ray L2 after exiting through the multiplexing lens 20 and the optical path of the third light ray L3 incident on the multiplexing lens 20 can be roughly symmetrical about the optical axis and approximately overlap, thereby ensuring the imaging effect of the projection device 100.
[0037] See also Figure 6 and Figure 7 , the first functional part 240 can surround the outer periphery of the second functional part 250, and the first functional part 240 and the second functional part 250 can be an integrally formed structure, for example, made by grinding the same transparent material (for example, glass). The first functional part 240 and the second functional part 250 can also be spliced by different lenses to improve the convenience of replacement for R&D personnel when debugging the optical path. Specifically, the surface shapes of the first functional part 240 and the second functional part 250 are both curved surfaces, for example, spherical surfaces, aspherical surfaces, conical surfaces, free-form surfaces, etc. In some possible embodiments, the surface shape of the first functional part 240 can be an aspherical surface, and the surface shape of the second functional part 250 can be a spherical surface.
[0038] Specifically, the first functional portion 240 may include a first surface 2410 and a second surface 2430, wherein the first surface 2410 is located on a side of the first functional portion 240 facing the illumination module 10, and the second surface 2430 is located on a side of the first functional portion 240 facing away from the illumination module 10. Specifically, the first surface 2410 and the second surface 2430 are both curved toward one side of the light modulator 30, the first surface 2410 is a concave surface, and the second surface 2430 is a convex surface. The first surface 2410 and the second surface 2430 may be spherical surfaces, aspherical surfaces, and the like.
[0039] The second functional portion 250 is approximately located at the center of the first functional portion 240, and may include a third surface 2510 and a fourth surface 2530. The third surface 2510 is located on the side of the second functional portion 250 facing the illumination module 10, and the fourth surface 2530 is located on the side of the second functional portion 250 facing away from the illumination module 10. Specifically, the third surface 2510 and the fourth surface 2530 are both curved toward one side of the light modulator 30, the third surface 2510 is a concave surface, and the fourth surface is a convex surface. The third surface 2510 and the fourth surface 2530 may be spherical surfaces, aspherical surfaces, and the like.
[0040] The third surface 2510 is approximately located at the center of the first surface 2410, and the third surface 2510 protrudes relative to the first surface 2410 toward the side of the light modulator 30. Specifically, the radius of curvature of the third surface 2510 is smaller than the radius of curvature of the first surface 2410, that is, the curvature of the third surface 2510 is greater than the curvature of the first surface 2410. The fourth surface 2530 is approximately located at the center of the second surface 2430, and the fourth surface 2530 protrudes relative to the second surface 2430 toward the side of the light modulator 30. Specifically, the radius of curvature of the fourth surface 2530 is smaller than the radius of curvature of the second surface 2430, that is, the curvature of the fourth surface 2530 is greater than the curvature of the second surface 2430.
[0041] In some possible embodiments, the radius of curvature of the third surface 2510 is smaller than the radius of curvature of the second surface 2430, that is, the curvature of the third surface 2510 is greater than the curvature of the second surface 2430, so that the light reflected at the second surface 2430 can be fully reflected to the third surface 2510, thereby improving the energy utilization efficiency of the projection device 100.
[0042] In this embodiment, the multiplexing lens 20 may be provided with a polarizing unit 230, which is disposed on the surface of the multiplexing lens 20 and is used to convert the first light L1 into the second light L2 and to transmit the third light L3. Figure 7, the polarization unit 230 may include a first polarization layer 2320 and a second polarization layer 2340, the first polarization layer 2320 covers the second surface 2430, and the second polarization layer 2340 covers the third surface 2510. Specifically, the first polarization layer 2320 may be plated on the second surface 2430, and the shape and size of the first polarization layer 2320 and the second surface 2430 may be substantially the same, so that the first polarization layer 2320 fully covers the second surface 2430. Similarly, the second polarization layer 2340 may be plated on the third surface 2510, and the shape and size of the second polarization layer 2340 and the third surface 2510 may be substantially the same, so that the second polarization layer 2340 fully covers the third surface 2510.
[0043] In this embodiment, the incident area 210 of the multiplexing lens 20 may be disposed in one of the first functional portion 240 or the second functional portion 250 , and the exit area 220 may be disposed in the other of the first functional portion 240 or the second functional portion 250 .
[0044] As an embodiment, the incident area 210 of the multiplexing lens 20 may be located on the first surface 2410 of the first functional portion 240, and the exit area 220 of the multiplexing lens 20 may be located on the third surface 2510 of the second functional portion 250, that is, the first light L1 is incident into the multiplexing lens 20 from the first surface 2410, and the third light L3 is emitted from the multiplexing lens 20 from the third surface 2510. Specifically, the first polarization layer 2320 and the second polarization layer 2340 are both used to reflect the light of the first polarization state and transmit the light of the second polarization state, and the first polarization layer 2320 can be used to convert the first light L1 into the second light L2.
[0045] Here, the propagation process of light in the multiplexing lens 20 is described by taking the first polarization state as the P polarization state and the second polarization state as the S polarization state as an example. Figure 2 and Figure 7 , the first light L1 is incident on the multiplexing lens 20 through the first surface 2410 of the first functional part 240, and when passing through the first polarization layer 2320 located on the second surface 2430, the P polarized light in the first light L1 is reflected and is incident on the multiplexing lens 20 again. At this time, the light incident on the multiplexing lens 20 is the second light L2 in the P polarization state, and the S polarized light in the first light L1 is transmitted out of the multiplexing lens 20 through the first polarization layer 2320. The second light L2 reflected by the first polarization layer 2320 is reflected again when passing through the second polarization layer 2340 located on the third surface 2510, and is emitted from the multiplexing lens 20 through the fourth surface 2530 of the second functional part 250.
[0046] Furthermore, when the second light L2 in the P polarization state passes through the optical modulator 30, it will be reflected by the optical modulator 30 and converted into the third light L3 in the S polarization state. The third light L3 will be incident on the multiplexing lens 20 from the fourth surface 2530 of the second functional part 250 again, and will sequentially pass through the second functional part 250 and the second polarization layer 2340 located on the third surface 2510 to exit. It is not difficult to understand here that Figure 2 The light propagation path shown is only schematic. The first light L1 can be incident on the multiplexing lens 20 from the entire area where the first surface 2410 is located, and the third light L3 can be emitted from the multiplexing lens 20 from the entire area where the third surface 2510 is located.
[0047] In this embodiment, the polarization unit 230 may further include a polarization absorption layer 2360, which is disposed on the side of the first polarization layer 2320 away from the first functional portion 240, and is used to absorb the light of the second polarization state transmitted through the first polarization layer 2320 to prevent the light of the second polarization state from being incident on the light modulator 30, thereby affecting the imaging effect of the light modulator 30. Exemplarily, when the first polarization state is a P polarization state and the second polarization state is an S polarization state, the polarization absorption layer 2360 is used to absorb the S polarized light transmitted through the first polarization layer 2320.
[0048] As another embodiment, the incident area 210 of the multiplexing lens 20 may be located on the third surface 2510 of the second functional portion 250, and the exit area 220 of the multiplexing lens 20 may be located on the first surface 2410 of the first functional portion 240, that is, the first light L1 is incident into the multiplexing lens 20 from the third surface 2510, and the third light L3 is emitted from the multiplexing lens 20 from the first surface 2410. Specifically, the first polarization layer 2320 and the second polarization layer 2340 are both used to reflect the light of the second polarization state and transmit the light of the first polarization state, and the second polarization layer 2340 can be used to convert the first light L1 into the second light L2.
[0049] Here, the propagation process of light in the multiplexing lens 20 is described by taking the first polarization state as the P polarization state and the second polarization state as the S polarization state as an example. Figure 7 and Figure 8 When the first light L1 enters the multiplexing lens 20 through the third surface 2510 of the second functional part 250, the P polarized light in the first light L1 will be transmitted and incident into the second functional part 250 when passing through the second polarization layer 2340 located on the third surface 2510. At this time, the light incident into the multiplexing lens 20 is the second light L2 in the P polarization state, and the second light L2 is emitted from the multiplexing lens 20 through the fourth surface 2530 of the second functional part 250, while the S polarized light in the first light L1 will be reflected by the second polarization layer 2340 and cannot enter the multiplexing lens 20.
[0050] Furthermore, when the second light L2 in the P polarization state passes through the optical modulator 30, it will be reflected by the optical modulator 30 and converted into the third light L3 in the S polarization state. The third light L3 will be incident on the multiplexing lens 20 from the fourth surface 2530 of the second functional part 250 again, and will be reflected by the second polarization layer 2340 and the first polarization layer 2320 in turn, and will be emitted through the first surface 2410 of the first functional part 240. It is not difficult to understand here that Figure 8 The light propagation path shown is only schematic. The first light L1 can be incident on the multiplexing lens 20 from the entire area where the third surface 2510 is located, and the third light L3 can be emitted from the multiplexing lens 20 from the entire area where the first surface 2410 is located.
[0051] In this embodiment, the projection area of the incident area 210 of the multiplexing lens 20 in the emission direction of the first light ray L1 covers the light emitting surface of the first light ray L1 , so that the first light ray L1 can be fully incident on the multiplexing lens 20 .
[0052] For some possible embodiments, please refer again to Figure 3 The incident area 210 of the multiplexing lens 20 can be located on the first surface 2410 of the first functional part 240, and the first surface 2410 can be roughly annular. At this time, the multiple lighting units 120 in the lighting module 10 can be arranged in a ring shape and arranged corresponding to the first surface 2410 in the optical path. Specifically, the projection area S1 of the first surface 2410 in the emission direction of the first light ray L1 can cover multiple lighting units 120.
[0053] In other possible embodiments, the incident area 210 of the multiplexing lens 20 can be located on the third surface 2510 of the second functional part 250, and the third surface 2510 can be roughly circular. In this case, the multiple lighting units 120 in the lighting module 10 can be arranged in a ring shape and evenly spaced, and can be arranged corresponding to the third surface 2510 in the optical path. Specifically, the projection area S2 of the third surface 2510 in the emitting direction of the first light ray L1 can cover multiple lighting units 120.
[0054] In this example, please refer again to Figure 2, the projection device 100 may further include an optical waveguide 40, which is disposed on the optical path of the third light L3 transmitted through the multiplexing lens 20, and is used to guide the propagation direction of the third light L3. For example, when a user wears the projection device 200 provided with the optical waveguide 40, the optical waveguide 40 may guide the third light L3 to propagate toward the user's eyes, so that the user can view the projected image carried in the third light L3. Specifically, the optical waveguide 40 may be a guiding structure for transmitting optical frequency electromagnetic waves made of a transparent material (e.g., glass), so that when the user views the projected image through the optical waveguide 40, he can also see the picture of the real external environment.
[0055] Specifically, the optical waveguide 40 may include a coupling portion 410, which is a light incident region of the optical waveguide 40. In the present embodiment, the coupling portion 410 and the emission region 220 are correspondingly arranged and are located on the optical path of the third light L3 transmitted through the multiplexing lens 20, so that the third light L3 emitted through the multiplexing lens 20 can be smoothly incident into the optical waveguide 40.
[0056] For some possible embodiments, please refer again to Figure 3 , the exit area 220 of the multiplexing lens 20 can be located on the third surface 2510 of the second functional part 250, and the third surface 2510 can be roughly circular. At this time, the coupling part 410 can also be roughly circular, and the coupling part 410 can cover the projection area S3 of the third surface 2510 in the exit direction of the third light L3, so that the third light L3 can be fully incident on the coupling part 410, thereby improving the energy utilization efficiency of the third light L3.
[0057] In other embodiments, please refer again to Figure 4 , the exit area 220 of the multiplexing lens 20 can be located on the first surface 2410 of the first functional part 240, and the first surface 2410 can be roughly annular. In this embodiment, the number of optical waveguides 40 can be two, and the two coupling parts 410 corresponding to the two optical waveguides 40 can be arranged corresponding to the projection area S4 of the first surface 2410 in the exit direction of the third light L3. For example, the two coupling parts 410 can overlap with the projection area S4 and be located on opposite sides of the illumination module 10. Therefore, in this embodiment, the third light L3 can be incident on the two optical waveguides 40, thereby realizing the binocular display of the projection device 100. In addition, the illumination module 10 and the optical modulator 30 can be applied to the two optical waveguides 40 at the same time, realizing the multiplexing of hardware, thereby saving the volume of the projection device 100 and saving the hardware cost of the projection device 100.
[0058] In this example, please refer again to Figure 2The projection device 100 may further include a lens group 50, which is disposed between the multiplexing lens 20 and the light modulator 30, and is used to transmit the second light L2 to the light modulator 30, and transmit the third light L3 to the multiplexing lens 20.
[0059] The lens group 50 may include one or more lenses (not shown in the figure), and the one or more lenses may be arranged in sequence along the optical path where the second light L2 is located, and the one or more lenses may play a role in correcting aberrations (for example, off-axis aberrations). Each lens may include an object side surface and an image side surface, and the object side surface and the image side surface are located on opposite sides of the lens, the image side surface is arranged toward the light modulator 30, and the object side surface is arranged away from the light modulator 30. Specifically, the lens may have a positive optical power or a negative optical power; the object side surface and the image side surface may be a spherical surface or an aspherical surface.
[0060] In this embodiment, when the lens group 50 transmits the second light L2 and the third light L3, the optical paths of the two should be roughly axially symmetrical, and the better the symmetry, the higher the imaging quality of the projection device 100. Furthermore, when the researchers actually design the optical parameters of the lens, they should give priority to the design of the imaging optical path system for the third light L3.
[0061] It is not difficult to understand here that the multiplexing lens 20 and one or more lenses included in the lens group 50 in this embodiment constitute the illumination optical path system of the light modulator 30. Since the multiplexing lens 20 located at the front end can play the role of separating polarized light, there is no need to add an additional PBS prism at the rear end of the lens group 50, which can make the overall structure of the projection device 100 more compact.
[0062] The embodiment of the present application provides a projection device 100 and a projection equipment 200 equipped with the projection device 100. The projection device 100 may include an illumination module 10, a multiplexing lens 20 and an optical modulator 30. The illumination module 10 is used to generate a first light ray L1. The multiplexing lens 20 is arranged on the optical path where the first light ray L1 is located, and is used to convert the first light ray L1 into a second light ray L2, and the polarization state of the second light ray L2 is a first polarization state. The optical modulator 30 is arranged on the optical path where the second light ray L2 is located, and is used to convert the second light ray L2 into a third light ray L3, and emit the third light ray L3 to the multiplexing lens 20, and the polarization state of the third light ray L3 is a second polarization state, and the second polarization state is different from the first polarization state. The multiplexing lens 20 is also used to transmit the third light ray L3.
[0063] On the one hand, the multiplexing lens 20 in this embodiment can convert the first light L1 into the second light L2 whose polarization state is the first polarization state, so that the second light L2 meets the illumination requirements of the light modulator 30. Therefore, the light modulator 30 in this application can be a display chip (for example, an LCOS chip) that requires polarized light as illumination light. On the other hand, the light carrying the image generated by the light modulator 30 (that is, the third light L3) is transmitted through the multiplexing lens 20, so that the multiplexing lens 20 can be used for projecting the image.
[0064] The multiplexing lens 20 in the projection device 100 provided in the present application has the functions of satisfying both the front lighting of the light modulator 30 and the image projection. Therefore, there is no need to set up an additional PBS prism in the projection device 100, which can make the overall structure of the projection device 100 more compact, thereby facilitating the miniaturization design of the projection equipment 200 equipped with the projection device 100.
[0065] In the specification of this application, certain words are used to refer to specific components in the specification and claims. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not use the difference in name as a way to distinguish components, but use the difference in function of the components as the criterion for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to"; "substantially" means that those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.
[0066] In the description of the present application, it should be understood that terms such as "upper", "lower", "front", "back", "left", "right", and "inside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are merely simplified descriptions for the convenience of describing the present application. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.
[0067] In this application, unless otherwise clearly specified or limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can be internal communication between two elements, or it can be only surface contact. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0069] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A projection device, characterized in that: include: An illumination module, used for generating a first light; a multiplexing lens, disposed on the optical path of the first light, and used for converting the first light into a second light, wherein the polarization state of the second light is the first polarization state; as well as an optical modulator, arranged on the optical path where the second light is located, for converting the second light into a third light, and emitting the third light to the multiplexing lens; the polarization state of the third light is a second polarization state, and the second polarization state is different from the first polarization state; and the multiplexing lens is also used to transmit the third light.
2. The projection device according to claim 1, characterized in that: The multiplexing lens is provided with an incident area, an exit area and a polarization unit; the incident area and the exit area are arranged on the same side of the multiplexing lens, the first light is incident through the incident area, and the third light is exited through the exit area; The polarization unit is disposed on the surface of the multiplexing lens, and is used for converting the first light into the second light.
3. The projection device according to claim 2, characterized in that: The multiplexing lens comprises a first functional portion and a second functional portion, the second functional portion and the first functional portion are adjacent to each other, and the curvature radius of the surface where the second functional portion and the first functional portion are connected is different; The incident area is disposed in one of the first functional portion or the second functional portion, and the exit area is disposed in the other of the first functional portion or the second functional portion.
4. The projection device according to claim 3, characterized in that: The first functional part surrounds the outer periphery of the second functional part; the first functional part comprises a first surface and a second surface, the first surface is located on a side of the first functional part facing the lighting module, and the second surface is located on a side of the first functional part facing away from the lighting module; The second functional portion includes a third surface and a fourth surface, the third surface is located on a side of the second functional portion facing the lighting module, and the fourth surface is located on a side of the second functional portion facing away from the lighting module; the curvature radius of the third surface is smaller than the curvature radius of the first surface, and the curvature radius of the fourth surface is smaller than the curvature radius of the second surface; The polarization unit includes a first polarization layer and a second polarization layer, the first polarization layer covers the second surface, and the second polarization layer covers the third surface.
5. The projection device according to claim 4, characterized in that: The incident area is located on the first surface, the exit area is located on the third surface, and the first polarization layer and the second polarization layer are both used to reflect light of a first polarization state and transmit light of a second polarization state; The first polarization layer is used to convert the first light into the second light.
6. The projection device according to claim 5, characterized in that: The polarization unit further includes a polarization absorption layer, which is disposed on a side of the first polarization layer away from the first functional portion and is used for absorbing light of the second polarization state transmitted through the first polarization layer.
7. The projection device according to claim 4, characterized in that: The incident area is located on the third surface, the exit area is located on the first surface, and the first polarization layer and the second polarization layer are both used to reflect the light of the second polarization state and transmit the light of the first polarization state; The second polarization layer is used for converting the first light into the second light.
8. The projection device according to claim 2, characterized in that: The lighting module comprises a plurality of lighting units, which are arranged at intervals on a side of the multiplexing lens away from the light modulator, and a projection area of the incident area in the emitting direction of the first light covers the light emitting surface of the first light.
9. The projection device according to claim 5, characterized in that: The projection device further comprises an optical waveguide, wherein the optical waveguide comprises an incoupling portion; The coupling-in portion and the third surface are arranged correspondingly and are located on the optical path where the third light transmitted by the multiplexing lens is located.
10. The projection device according to claim 1, characterized in that: The projection device further includes a lens group, which is disposed between the multiplexing lens and the light modulator and is used to transmit the second light to the light modulator and transmit the third light to the multiplexing lens.