Optical module and electronic equipment
By employing curved surface design and freeform surface technology in the optical module, the structure of the optical module is optimized, solving the problems of large optical module thickness and poor imaging quality. This achieves a thinner and lighter optical module with high-quality imaging, thus improving the user experience.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUAWEI DEVICE CO LTD
- Filing Date
- 2024-11-06
- Publication Date
- 2026-05-08
AI Technical Summary
The existing optical modules are generally thick, have poor image quality, and are prone to distortion of ambient light during propagation, affecting the user's viewing area and user experience.
The optical surface through which polarized light passes is designed as a curved surface, especially the fourth and third optical surfaces which are curved surfaces with the same shape. Combined with the freeform surface design, the structure of the optical module is optimized, aberrations are reduced and imaging quality is improved. At the same time, the optical path and structural compactness are optimized through the combination of optical film layers and prisms.
The overall thickness of the optical module has been reduced, improving image quality, reducing aberrations and distortions, expanding the visible area, and enhancing the user's wearing experience and usage effect.
Smart Images
Figure CN121995629A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of terminal technology, specifically to an optical module and electronic device. Background Technology
[0002] With the development of display technology, near-eye display technologies such as augmented reality (AR) have been widely applied, giving rise to head-mounted display devices. In head-mounted display devices, the images provided by the display panel need to be processed by optical modules before being presented to the user. Among these, geometric optics is currently the main optical display solution for head-mounted display devices due to its mature technology. However, in related technologies, geometric optics solutions result in a relatively large overall thickness of the optical module, leading to poorer image quality. Summary of the Invention
[0003] In view of this, this application provides an optical module and electronic device to solve the problems of large overall thickness and poor imaging quality of optical modules in the prior art.
[0004] A first aspect of this application provides an optical module including a display component, a first prism, a polarizing reflective layer, a second prism, and a third prism. The display component includes a light-emitting surface for emitting polarized light. The first prism is disposed on the light-emitting surface side of the display component and includes a first optical surface and a second optical surface. The polarizing reflective layer is disposed on the side of the first prism having the first optical surface. The second prism is disposed on the side of the first prism having the second optical surface and includes a third optical surface disposed on a side away from the second optical surface. The third prism is disposed on the side of the polarizing reflective layer opposite to the first optical surface and includes a fourth optical surface disposed on a side away from the first optical surface. The polarized light emitted by the display component can be reflected sequentially by the first optical surface, the second optical surface, the polarizing reflective layer, and the third optical surface, and then pass through the fourth optical surface to enter the human eye. The fourth optical surface and the third optical surface are curved surfaces with the same shape.
[0005] In this application, polarized light emitted from the light-emitting surface of the display component enters the first prism and is reflected sequentially by the first optical surface, the second optical surface, the polarization reflection layer, and the third optical surface before passing through the fourth optical surface and entering the human eye, thereby forming a virtual image. Since polarized light is prone to aberrations during propagation, by making the fourth and third optical surfaces curved, they can work together during the propagation of polarized light, improving the aberration correction capability, reducing aberrations in the optical module, and improving the imaging quality of the optical module. Furthermore, because the fourth and third optical surfaces have the same surface shape, the optical module can be formed with a uniform thickness, reducing the overall thickness of the optical module and making its shape closer to that of eyeglass lenses, thus improving the user's wearing experience. Furthermore, the ambient light in this structure passes through the second prism, the first prism, and the third prism in sequence with the same optical path. The transition between the fourth optical surface and the first optical surface of the curved structure is smoother, which makes it less likely for the ambient light transmitted to the human eye to be distorted and the imaging of external objects to be distorted. This helps to increase the visible area of the external environment that the user can see through the optical components and improves the user experience.
[0006] In one possible design, the first prism further includes a fifth optical surface, which is disposed on the side close to the display component and connected to the first optical surface and the second optical surface. At least two of the fifth optical surface, the first optical surface, the second optical surface, and the third optical surface are freeform surfaces.
[0007] Freeform surfaces offer a high degree of design freedom, flexibility, and adjustability. Their shape and curvature can be designed according to specific optical requirements to achieve specific optical effects and superior optical performance. At least two of the aforementioned fifth, first, second, and third optical surfaces are freeform surfaces. This allows them to work together during the propagation of polarized light, further enhancing aberration correction and improving the imaging quality of the optical module. Furthermore, designing complex freeform surfaces can integrate the functions of multiple optical elements into a single element. This allows for a reduction in the overall thickness of the optical module without altering the optical path of polarized light, and also reduces the use of compensating prisms, further decreasing the module's size and weight, thus achieving a compact design.
[0008] In one possible design, the first optical surface is a freeform surface.
[0009] Polarized light rays pass through the first optical surface multiple times during transmission. Therefore, when the first optical surface is a freeform surface, aberrations can be corrected each time the polarized light rays pass through the first optical surface, improving the usability of the first optical surface, enhancing the imaging quality of the optical module, and reducing the number of freeform surfaces in the optical module, thereby reducing the structural complexity of the optical module and facilitating its fabrication and processing.
[0010] In one possible design, polarized light rays incident on the first optical surface via the display component have an incident angle at the first optical surface that is greater than or equal to the critical angle for total internal reflection.
[0011] This structure enables polarized light rays incident on the first optical surface via the display component to undergo total internal reflection on the first optical surface, thereby improving the utilization rate of polarized light rays and thus enhancing the optical efficiency of the optical module.
[0012] In one possible design, the first optical surface includes a first reflective area and a first transmissive area, which are arranged sequentially along a direction away from the display component. Polarized light can be reflected by the first reflective area to the second optical surface and exit or enter the first prism through the first transmissive area. The third prism is spaced apart from the first prism at least at the position of the first reflective area.
[0013] This structure enables an air gap to be formed between the third prism and the first prism, at least at the position of the first reflection zone. Since the refractive index of the first prism is greater than that of air, the deflected light rays entering the first reflection zone are from an optically denser medium to an optically less dense medium, thus satisfying the total internal reflection condition of polarized light rays in the first reflection zone. This allows polarized light rays to achieve total internal reflection in the first reflection zone without needing to consider the refractive index of the third prism. The structure is simple and easy to implement.
[0014] In one possible design, the polarized light reflected from the first optical surface to the second optical surface has an incident angle at the second optical surface that is greater than or equal to the critical angle for total internal reflection.
[0015] This structure enables polarized light reflected from the first optical surface to the second optical surface to undergo total internal reflection on the second optical surface, thereby improving the utilization rate of polarized light and thus enhancing the optical efficiency of the optical module.
[0016] In one possible design, the second optical surface includes a second reflective area and a second transmissive area, which are arranged sequentially in a direction away from the display component. Polarized light can be reflected by the second reflective area to the first optical surface and exit or enter the first prism through the second transmissive area. The second prism and the first prism are spaced apart at least at the position of the second reflective area.
[0017] This structure enables an air gap to be formed between the second prism and the first prism at least at the position of the second reflection zone. Since the refractive index of the first prism is greater than that of air, the deflected light rays entering the second reflection zone are from an optically denser medium to an optically less dense medium, thus satisfying the total internal reflection condition of polarized light rays in the second reflection zone. This allows polarized light rays to achieve total internal reflection in the second reflection zone without needing to consider the refractive index of the second prism. The structure is simple and easy to implement.
[0018] In one possible design, the optical module further includes a first reflector attached to the second reflective area. Polarized light rays reflected from the first optical surface to the second optical surface can undergo total internal reflection via the first reflector.
[0019] By attaching a first reflector to the second reflective area, partially polarized light reflected from the first optical surface to the second optical surface can undergo total internal reflection through the first reflector, thereby improving the utilization rate of polarized light in the display module and enhancing image quality. The structure is simple and easy to implement. It can also reduce the incident angle requirement for total internal reflection of polarized light reflected from the first optical surface to the second optical surface. It can be adapted to first prisms made of more materials and can also reduce the fabrication requirements of the first optical surface, further reducing the fabrication difficulty of the optical module.
[0020] In one possible design, the optical module further includes a first optical film layer, which is attached to the first optical surface. At least a portion of the polarized light rays incident on the first optical surface by the display component can be reflected by the first optical film layer to the second optical surface.
[0021] By attaching a first optical film layer to the first optical surface, at least part of the polarized light emitted from the display component toward the first optical surface can be reflected by the first optical film layer toward the second optical surface. This simplifies the manufacturing process, further reduces the manufacturing difficulty of the optical module, and lowers the incident angle requirement of the polarized light emitted from the display component on the first optical surface. It can also be adapted to first prisms made of more materials and adjust the placement of the display component, which helps to improve the structural compactness of the optical module.
[0022] In one possible design, the first optical film layer is a total reflection film, a polarizing reflection film, or a beam splitter film.
[0023] When the first optical film layer is a polarizing reflective film or a beam-splitting film, some polarized light rays incident on the first optical surface from the display component can be reflected by the first optical film layer to the second optical surface. This reduces the utilization of polarized light, thereby lowering the brightness of the image. This allows display components with higher brightness (such as those with high-brightness LCOS displays) to better match the brightness range acceptable to the human eye, improving the user experience. When the first optical film layer is a total internal reflection film, polarized light rays incident on the first optical surface from the display component can undergo total internal reflection by the first optical film layer. This improves the utilization rate of polarized light by the display module, enhances image quality, and reduces the incident angle requirement for total internal reflection of polarized light emitted from the display component on the first optical surface. It also allows for the adaptation of first prisms made of more materials and the adjustment of the display component's placement position, which is beneficial for further improving the structural compactness of the optical module.
[0024] In one possible design, the optical module further includes a second optical film layer, which is attached to the second optical surface. At least a portion of the polarized light reflected from the first optical surface to the second optical surface can be reflected back to the first optical surface by the second optical film layer.
[0025] By attaching a second optical film to the second optical surface, at least a portion of the polarized light reflected from the first optical surface to the second optical surface can be reflected back to the first optical surface through the second optical film. This simplifies the manufacturing process, reduces the incident angle requirement of the polarized light reflected from the first optical surface to the second optical surface, allows for the use of more types of first prisms, and lowers the manufacturing requirements for the first optical surface, further reducing the manufacturing difficulty of the optical module.
[0026] In one possible design, the second optical film layer is a total reflection film, a polarizing reflection film, or a beam splitting film.
[0027] When the second optical film is a polarizing reflective film or a beam-splitting film, some polarized light reflected from the first optical surface to the second optical surface can be reflected back to the first optical surface by the second optical film, thereby reducing the utilization of polarized light and lowering the brightness of the image. This allows display components with higher brightness (such as those with high-brightness LCOS displays) to better match the brightness range acceptable to the human eye, improving the user experience. When the second optical film is a total internal reflection film, some polarized light reflected from the first optical surface to the second optical surface can undergo total internal reflection by the second optical film, thereby improving the utilization rate of polarized light by the display module, improving image quality, and reducing the incident angle requirement for total internal reflection of polarized light reflected from the first optical surface to the second optical surface. This allows for the adaptation of more types of first prism materials and reduces the fabrication requirements of the first optical surface, further reducing the fabrication difficulty of the optical module.
[0028] In one possible design, the second prism covers at least part or all of the second reflective area, and the third prism covers at least part of the first reflective area, allowing ambient light to enter the human eye sequentially through the second prism, the first prism, and the third prism.
[0029] This structure can expand the visible area of the external environment that users can see through the optical components, i.e., the area shown by the ambient light in the figure. It also helps to form the optical module as a uniformly thick arc-shaped sheet structure and ensures the integrated appearance of the optical module. This makes the shape of the optical module closer to that of eyeglass lenses, improving the user's wearing experience.
[0030] In one possible design, the optical module further includes a phase retardation layer disposed between the first prism and the second prism.
[0031] The phase retardation layer is used to change the polarization state of polarized light. The phase retardation layer is disposed between the first prism and the second prism. It can change the polarization state of the polarized light entering the first prism after being reflected by the third optical surface, so that the polarization direction of the polarized light transmitted through the second transmission area and the first transmission area in sequence is parallel to the direction of the light transmission axis of the polarization reflection layer, so that the polarized light can pass through the polarization reflection layer and enter the third prism.
[0032] In one possible design, the phase delay layer is a quarter-wave plate.
[0033] Polarized light reflected by the polarizing reflective layer passes sequentially through the first and second transmission regions and exits the first prism. It then passes through the phase retardation layer into the second prism and is reflected on the third optical surface. At least a portion of the light, after reflection from the third optical surface, can re-enter the first prism through the phase retardation layer. A quarter-wave plate, also known as a 45° phase retardation plate, rotates the polarization state of polarized light by 90° when the polarized light passes through it twice. This makes the polarization direction of the polarized light parallel to the transmission axis of the polarizing reflective layer, allowing the polarized light to pass through the polarizing reflective layer and enter the third prism.
[0034] In one possible design, the second prism further includes a sixth optical surface disposed on a side close to the second optical surface, the sixth optical surface having the same surface shape as the second optical surface.
[0035] The sixth optical surface has the same surface shape as the second optical surface, which reduces the gap between them in the thickness direction, further improving the structural compactness of the optical module in the thickness direction, thus facilitating the design of a thinner and lighter optical module. Furthermore, the identical surface shape of the sixth optical surface with the second optical surface also reduces the risk of distortion of ambient light reaching the human eye, thereby increasing the visible range of the external environment through the optical components.
[0036] In one possible design, the third prism further includes a seventh optical surface disposed on a side close to the first optical surface, the seventh optical surface having the same surface shape as the first optical surface.
[0037] The seventh optical surface has the same surface shape as the first optical surface, which reduces the gap between them in the thickness direction, further improving the structural compactness of the optical module in the thickness direction, thus facilitating the design of a thinner and lighter optical module. Furthermore, the identical surface shape of the seventh optical surface to the first optical surface also reduces the risk of distortion of ambient light reaching the human eye, thereby increasing the visible range of the external environment through the optical components.
[0038] In one possible design, the optical module further includes a prism group disposed between the first prism and the third prism, the prism group including at least one prism, and the polarizing reflection layer being disposed on the surface of the prism group near the third prism.
[0039] The prism group can increase the design freedom of the optical module, and also increase the number of optical surfaces through which polarized light passes, thereby further improving the aberration correction effect, improving the imaging quality of the optical module, and reducing the volume of the first prism, thus reducing the manufacturing difficulty of the first prism.
[0040] A second aspect of this application provides an electronic device comprising a frame and an optical module as described in any of the above embodiments, the optical module being mounted on the frame. Since the optical module possesses the aforementioned technical effects, the electronic device including this optical module should also possess corresponding technical effects, which will not be elaborated further here.
[0041] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description
[0042] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0043] Figure 1 This is a schematic diagram of the structure of an optical module in related technologies;
[0044] Figure 2 A schematic diagram of the structure of an electronic device provided in this application;
[0045] Figure 3 A schematic diagram of the structure of the optical module provided in this application in a specific embodiment;
[0046] Figure 4 An imaging quality simulation result curve of an optical module provided in this application;
[0047] Figure 5 A schematic diagram of the structure of the optical module provided in this application in another specific embodiment;
[0048] Figure 6 A schematic diagram of the structure of the display module provided in this application in another specific embodiment;
[0049] Figure 7 A schematic diagram of the structure of the display module provided in this application in another specific embodiment;
[0050] Figure 8 A schematic diagram of the structure of the display module provided in this application in another specific embodiment;
[0051] Figure 9 A schematic diagram of the structure of the display module provided in this application in another specific embodiment;
[0052] Figure 10 This is a schematic diagram of the structure of the display module provided in this application in another specific embodiment.
[0053] Figure label:
[0054] 1'-Display component;
[0055] 2' - First prism;
[0056] 21' - First optical surface;
[0057] 22' - Second optical surface;
[0058] 3' - Second prism;
[0059] 31' - Third optical surface;
[0060] 4'-Third prism;
[0061] 41' - Fourth optical surface;
[0062] 5' - Human eye plane;
[0063] 100 - Electronic devices;
[0064] 10-Optical Module;
[0065] 1- Display components;
[0066] 11-Light-emitting surface;
[0067] 2-First prism;
[0068] 21-First optical surface;
[0069] 211 - First Reflection Zone;
[0070] 212 - First transmission zone;
[0071] 22-Second optical surface;
[0072] 221 - Second Reflection Zone;
[0073] 222 - Second transmission zone;
[0074] 23 - Fifth optical surface;
[0075] 3-Second prism;
[0076] 31 - Third optical surface;
[0077] 32 - Sixth optical surface;
[0078] 4-Third prism;
[0079] 41 - Fourth optical surface;
[0080] 42 - Seventh optical surface;
[0081] 5-Polarization reflective layer;
[0082] 6-Phase delay layer;
[0083] 7a - First optical coating layer;
[0084] 7b - Second optical coating layer;
[0085] 8-First reflector;
[0086] 9a - Prism Group;
[0087] 9b - Fourth prism;
[0088] 20 - Eyeglass frames;
[0089] 30-temples;
[0090] 200 - human eye;
[0091] 300° polarized light;
[0092] 400 - Ambient light.
[0093] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. Detailed Implementation
[0094] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.
[0095] In the description of this application, unless otherwise expressly specified and limited, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; unless otherwise specified or explained, the term "multiple" refers to two or more; the terms "connected," "fixed," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0096] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.
[0097] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.
[0098] With the development of display technology, near-eye display technologies such as augmented reality (AR) have been widely used, giving rise to head-mounted display devices. In head-mounted display devices, the images provided by the display panel need to be processed by optical modules before being presented to the user. Among these, geometric optics is currently the main optical display solution for head-mounted display devices due to its mature technology.
[0099] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of an optical module in related technologies.
[0100] like Figure 1 As shown, the optical module employing a geometric optics scheme in related technologies consists of a display module 1', a first prism 2', a second prism 3', and a third prism 4'. A polarizing reflective film or a semi-transparent reflective film can be disposed between the third prism 4' and the first prism 2', allowing polarized light emitted from the display module 1' to enter the first prism 2' and sequentially pass through the first optical surface 21', the second optical surface 22', the polarizing reflective film or semi-transparent reflective film between the third prism 4' and the first prism 2', and the third optical surface 31' before being reflected through the fourth optical surface 41' and entering the human eye. However, polarized light is prone to aberrations during propagation.
[0101] However, in related technologies, such as Figure 1 As shown, the optical surfaces of the first prism 2' and the third prism 4', which are located near the human eye plane 5', are mostly planar. For example, the first optical surface 21', the second optical surface 22', and the fourth optical surface 41' are mostly planar, resulting in poor aberration correction and poor imaging quality of the optical module. In contrast, the optical surfaces of the second prism 3', which are located away from the human eye plane 5', are mostly curved. For example, the third optical surface 31' is curved, resulting in uneven overall thickness of the optical module and a larger overall thickness d'.
[0102] Furthermore, due to the different surface shapes of the third optical surface 31' and the fourth optical surface 41', ambient light is prone to distortion as it passes through the second prism 3', the first prism 2', and the third prism 4' before entering the human eye. This causes the image of external objects to be distorted, thus affecting the user's visible area of the external environment through the optical components. Moreover, since the fourth optical surface 41' is planar, the junction between it and the first optical surface 21' has sharp edges. This also causes refraction as ambient light propagates to the human eye plane 5', further distorting the image of external objects and impacting the user's visible area of the external environment through the optical components, thereby reducing the user's field of vision.
[0103] Distortion (DIST) refers to the deformation that occurs between the actual projection and the ideal projection (or between the actual image plane and the ideal image plane) when an object is projected (or imaged) through a lens. In other words, after the image is projected, the projection of the image is not a proportional scaling of the image (or, after the object is imaged, the image of the object is not the object itself). Due to the unequal local magnification, the projection of the image (or the image of the object) is deformed, which is also called distortion.
[0104] In view of this, this application provides an optical module that can be applied to head-mounted electronic devices such as XR head-mounted display devices, AR head-mounted display devices, VR head-mounted display devices, and MR head-mounted display devices in virtual reality technologies such as Extended Reality (XR), Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR). The head-mounted display device can take the form of glasses or a helmet, etc. The embodiments of this application do not impose any special limitations on the specific form of the above-mentioned electronic devices.
[0105] For ease of explanation, the following description uses AR glasses as an example. The present application will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings.
[0106] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the structure of an electronic device provided in this application.
[0107] like Figure 2 As shown, the electronic device 100 may include an optical module 10 and a frame, with the optical module 10 mounted on the frame. Specifically, the frame includes a lens frame 20 and temples 30.
[0108] The optical module 10 is used to display virtual images to the user and also allows the user to observe the real environment through the display module 10. The optical module 10 is fixed to the frame 20 and is fixed by the frame 20 at a viewing position relative to the human eye. Temples 30 are connected to opposite sides of the frame 20 so that the electronic device 100 can be worn on the head by the user in the form of glasses.
[0109] It should be noted that electronic device 100 may also include more than Figure 2 The more or fewer physical units shown, such as electronic device 100, may also include physical units such as camera, antenna, speaker, horn, and battery. The specific configuration can be set according to actual needs and is not limited here.
[0110] Please refer to Figure 3 , Figure 3 A schematic diagram of the structure of the optical module provided in this application in a specific embodiment.
[0111] like Figure 3 As shown, the optical module 10 includes a display component 1, a first prism 2, a second prism 3, a third prism 4, and a polarizing reflective layer 5.
[0112] The display component 1 includes a light-emitting surface 11 for emitting polarized light 300. The display component 1 may include any suitable components for generating images for display. In some embodiments, the display component 1 may include a reflective microdisplay, such as a liquid crystal on silicon (LCoS) display. In other embodiments, the display component 1 may include an emitting microdisplay, such as an organic light-emitting diode (OLED) array display, an inorganic light-emitting diode (iLED) array display, and / or any other suitable microdisplay. The display component 1 may include one or more light sources, such as an RGB LED array, one or more white LEDs (e.g., with a color filter device), and / or any suitable illumination source structure, which can be configured according to actual needs and is not limited herein. In one specific embodiment, the display component 1 may include a display and a polarizer, the polarizer being disposed on the light-emitting side of the display, so that the light emitted by the display can be polarized by the polarizer to form polarized light. The polarizer may be a polarizing film or a polarizer plate, which can be configured according to actual needs and is not limited herein.
[0113] like Figure 3 As shown, the first prism 2 is disposed on the light-emitting surface 11 side of the display component 1. The first prism 2 includes a first optical surface 21 and a second optical surface 22. The polarized light 300 emitted by the display component 1 through the light-emitting surface 11 enters the first prism 2, is reflected by the first optical surface 21 to the second optical surface 22, is then reflected by the second optical surface 22 back to the first optical surface 21, and is transmitted out through the first optical surface 21.
[0114] A polarizing reflective layer 5 is disposed on the side of the first prism 2 having the first optical surface 21. The polarizing reflective layer 5 is used to reflect the polarized light 300 reflected by the second optical surface 22 to the first optical surface 21 and transmitted through the first optical surface 21. The polarized light 300 reflected by the deflecting reflective layer 5 is transmitted through the first optical surface 21 and the second optical surface 22 in sequence.
[0115] Among them, the polarization reflective layer 5 can be a polarization reflective film or a polarization beam splitter film, or it can be a composite film made of a linear polarization film and a polarization reflective film, or a composite film made of a linear polarization film, a polarization reflective film and a phase retardation film, or a composite film made of a linear polarization film, a polarization reflective film, a phase retardation film and an anti-reflection film. The specific settings can be set according to actual needs, and there are no restrictions here.
[0116] The second prism 3 is disposed on the side of the first prism 2 having the second optical surface 22. The second prism 3 includes a third optical surface 31, which is disposed on the side of the second prism 3 away from the second optical surface 22. The polarized light 300 transmitted through the second optical surface 22 enters the second prism 3 and is reflected by the third optical surface 31. The light reflected by the third optical surface 31 then enters the first prism 2 again through the second optical surface 22, and is transmitted out sequentially through the first optical surface 21 and the polarization reflective layer 5.
[0117] The third optical surface 31 of the second prism 3 may be provided with a semi-transparent and semi-reflective film or other film layers with different beam splitting ratios, so that the third optical surface 31 can reflect at least part of the light reflected onto the third optical surface 31, thereby ensuring the propagation path of the light.
[0118] The third prism 4 is disposed on the side of the polarizing reflective layer 5 away from the first optical surface 21. The third prism 4 includes a fourth optical surface 41, which is disposed on the side away from the first optical surface 21. The polarized light 300 transmitted through the polarizing reflective layer 5 enters the third prism 4 and can be transmitted through the fourth optical surface 41 to enter the human eye 200.
[0119] Among them, the fourth optical surface 41 and the third optical surface 31 are curved surfaces and have the same surface shape.
[0120] In this embodiment, as Figure 3 As shown, polarized light 300 emitted from the light-emitting surface 11 of the display component 1 enters the first prism 2 and is reflected sequentially by the first optical surface 21, the second optical surface 22, the polarization reflection layer 5, and the third optical surface 31 before passing through the fourth optical surface 41 and entering the human eye 200, thereby forming a virtual image. The polarized light 300 is prone to aberrations during propagation. By setting the fourth optical surface 41 and the third optical surface 31 as curved surfaces, they can work together during the propagation of the polarized light 300, improving the aberration correction capability, reducing the aberrations of the optical module 10, and improving the imaging quality of the optical module 10. Furthermore, since the fourth optical surface 41 and the third optical surface 31 have the same surface shape, the optical module 10 can be formed into a structure with a uniform thickness d, reducing the overall thickness d of the optical module 10 and making its shape closer to that of eyeglass lenses, thus improving the user's wearing experience. Furthermore, the ambient light in this structure passes through the second prism 3, the first prism 2, and the third prism 4 in sequence with the same optical path. The transition between the fourth optical surface 41 and the first optical surface 21 of the curved structure can be smoother, so that the ambient light propagating to the human eye 200 is less likely to be distorted and the imaging of external objects is less likely to be distorted. This helps to increase the visible area of the external environment that the user can see through the optical component 10, thus improving the user experience.
[0121] Please refer to Figure 4 , Figure 4 The simulation results curve of the imaging quality of an optical module provided in this application is shown. Figure 4 The simulation results of the imaging quality are presented as an MTF chart, where the contrast between black and white line pairs characterizes the imaging sharpness of the optical module. Figure 4 The horizontal axis represents spatial frequency, represented by alternating black and white line pairs, with the unit being period / mm. The vertical axis represents the optical transfer function (OTF) modulus, which indicates contrast. The OTF modulus ranges from 0 to 1. The closer the value is to 1, the better the imaging quality of the optical module and the smaller the smallest detail that can be resolved. Figure 4 The curves in the figure represent the variation of the OTF modulus of the image formed by optical module 10 under different fields of view with spatial frequency. Figure 4 As can be seen, the OTF modulus of the optical module 10 under different fields of view is above 0.1, indicating that the optical module 10 of this application has high imaging quality and good image clarity.
[0122] Specifically, such as Figure 3 As shown, the fourth optical surface 41 and the third optical surface 31 are curved surfaces that are concave towards the side away from the human eye 200, so that the overall shape of the optical module is closer to the shape of eyeglass lenses, improving the user's wearing experience.
[0123] Among them, the fourth optical surface 41 and the third optical surface 31 can be freeform surfaces, aspherical surfaces, quadric surfaces or spheres, and can be set according to actual needs, without restrictions here.
[0124] like Figure 3 As shown, the first prism 2 also includes a fifth optical surface 23, which is disposed on the side close to the display component 1 and connected to the first optical surface 21 and the second optical surface 22. The fifth optical surface 23 is used to receive polarized light 300 emitted from the display component 1. In this structure, the first prism 2 is composed of the first optical surface 21, the second optical surface 22 and the fifth optical surface 23, which can ensure the function of the first prism 2 in the propagation process of polarized light 300, and the structure is simple and easy to manufacture.
[0125] The fifth optical surface 23 can be a freeform surface, aspherical surface, quadric surface, spherical surface or plane, etc., to improve the design freedom of the optical module 10. The specific design can be set according to actual needs and is not limited here.
[0126] like Figure 3As shown, the third prism 4 also includes a seventh optical surface 42, which is disposed on the side of the third prism closest to the first optical surface 21. The seventh optical surface 42 has the same surface shape as the first optical surface 21, thereby reducing the mating gap between the seventh optical surface 42 and the first optical surface 21 in the thickness direction. This further improves the structural compactness of the optical module 10 in the thickness direction, thus facilitating a thinner and lighter design for the optical module 10. Furthermore, the identical surface shape of the seventh optical surface 42 and the first optical surface 21 also further reduces the risk of distortion of ambient light propagating to the human eye 200, thereby increasing the visible range of the external environment that the user can see through the optical component 10.
[0127] Among them, the first optical surface 21 and the seventh optical surface 42 can be freeform surfaces, aspherical surfaces, quadric surfaces, spherical surfaces or planes, etc., to improve the design freedom of the optical module 10. The specific settings can be set according to actual needs, and no restrictions are imposed here.
[0128] In addition, the aforementioned polarizing reflective layer 5 can be attached to the first optical surface 21 of the first prism 2, or to the seventh optical surface 42 of the third prism 4, or can be independently disposed between the first prism 2 and the third prism 4. The specific arrangement can be made according to actual needs, and no restrictions are imposed here.
[0129] Please refer to Figure 5 , Figure 5 This is a schematic diagram of the structure of the optical module provided in this application in another specific embodiment.
[0130] like Figure 5 As shown, the second prism 3 also includes a sixth optical surface 32, which is disposed on the side of the second prism 3 closest to the second optical surface 22. The sixth optical surface 32 has the same surface shape as the second optical surface 22, thereby reducing the mating gap between the sixth optical surface 32 and the second optical surface 22 in the thickness direction. This further improves the structural compactness of the optical module 10 in the thickness direction, thus facilitating a thinner and lighter design for the optical module 10. Furthermore, the identical surface shape of the sixth optical surface 32 and the second optical surface 22 also further reduces the risk of distortion of ambient light propagating to the human eye 200, thereby increasing the visible range of the external environment that the user can see through the optical component 10.
[0131] The second optical surface 22 and the sixth optical surface 32 can be freeform surfaces, aspherical surfaces, quadric surfaces, spherical surfaces or planes, etc., to improve the design freedom of the optical module 10. The specific settings can be made according to actual needs, and no restrictions are imposed here.
[0132] In one specific embodiment, such as Figure 5As shown, at least two of the aforementioned fifth optical surface 23, first optical surface 21, second optical surface 22, and third optical surface 31 are freeform surfaces.
[0133] In this embodiment, as Figure 5 As shown, freeform surfaces offer high design freedom, flexibility, and adjustability. Their shape and curvature can be designed according to specific optical requirements to achieve specific optical effects and superior optical performance. At least two of the aforementioned fifth optical surface 23, first optical surface 21, second optical surface 22, and third optical surface 31 are freeform surfaces. This allows at least two freeform surfaces to cooperate during the propagation of polarized light 300, further enhancing aberration correction and improving the imaging quality of the optical module 10.
[0134] In addition, by designing complex freeform surfaces, the effects of multiple optical elements can be combined into one optical element, thereby further reducing the overall thickness of the optical module 10 without changing the 300 optical path of the polarized light, and reducing the use of compensation prisms in the optical module 10, thereby further reducing the size and weight of the optical module 10 and achieving a compact design of the optical module 10.
[0135] For example, two of the first optical surface 21, the fifth optical surface 23, the second optical surface 22, and the third optical surface 31 are freeform surfaces. For example, the first optical surface 21 and the third optical surface 31 are freeform surfaces, or the first optical surface 21 and the fifth optical surface 23 are freeform surfaces, or the first optical surface 21 and the second optical surface 22 are freeform surfaces, or the second optical surface 22 and the fifth optical surface 23 are freeform surfaces, or the second optical surface 22 and the third optical surface 31 are freeform surfaces, etc. For example, three of the first optical surface 21, the fifth optical surface 23, the second optical surface 22, and the third optical surface 31 may be freeform surfaces. For instance, the first optical surface 21, the fifth optical surface 23, and the second optical surface 22 may be freeform surfaces, or the first optical surface 21, the fifth optical surface 23, and the third optical surface 31 may be freeform surfaces, or the fifth optical surface 23, the second optical surface 22, and the third optical surface 31 may all be freeform surfaces. For example, the first optical surface 21, the fifth optical surface 23, the second optical surface 22, and the third optical surface 31 may all be freeform surfaces.
[0136] The number and arrangement of freeform surfaces in the fifth optical surface 23, the first optical surface 21, the second optical surface 22, and the third optical surface 31 can be set according to actual needs to further enhance the design freedom of the optical module 10. As long as at least two optical surfaces are freeform surfaces, there are no restrictions here.
[0137] In one specific embodiment, the first optical surface 21 is a freeform surface. For example... Figure 5 As shown, the polarized light 300 passes through the first optical surface 21 multiple times during its transmission. Therefore, when the first optical surface 21 is a freeform surface, aberrations can be corrected every time the polarized light 300 passes through the first optical surface 21, improving the usability of the first optical surface 21, enhancing the imaging quality of the optical module 10, and reducing the number of freeform surfaces in the optical module 10, thereby reducing the structural complexity of the optical module 10 and facilitating its fabrication.
[0138] Furthermore, the first optical surface 21 and the third optical surface 31 are freeform surfaces, which allows the first optical surface 21 and the third optical surface 31 to cooperate with each other during the propagation of polarized light 300, better correcting aberrations and further improving the imaging quality of the optical module 10.
[0139] In addition, the materials of the first prism 2, the second prism 3, and the third prism 4 can be optical glass or plastic and other materials with high light transmittance, so that the optical module 10 has good light transmission and projection effects. The materials of each prism can be the same, different, or some prisms can be made of the same material, so as to improve the design freedom of the optical module 10. The specific settings can be set according to actual needs, and no restrictions are imposed here.
[0140] In one specific embodiment, such as Figure 5 As shown, the polarized light 300 incident on the first optical surface 21 via the display component 1 has an incident angle on the first optical surface 21 that is greater than or equal to the critical angle for total internal reflection. This allows the polarized light 300 incident on the first optical surface 21 via the display component 1 to undergo total internal reflection, thereby improving the utilization rate of the polarized light 300 and thus improving the optical efficiency of the optical module 10.
[0141] Furthermore, such as Figure 5 As shown, the first optical surface 21 includes a first reflective area 211 and a first transmissive area 212, which are arranged sequentially along a direction away from the display component 1. Polarized light 300 can be reflected by the first reflective area 211 towards the second optical surface 22, and can exit or enter the first prism 2 through the first transmissive area 212. The third prism 4 is spaced apart from the first prism 2 at least at the position of the first reflective area 211.
[0142] In this embodiment, as Figure 5 As shown, this structure enables an air gap to be formed between the third prism 4 and the first prism 2 at least at the position of the first reflection region 211. Since the refractive index of the first prism 2 is greater than that of air, the refracted ray 300 enters the first reflection region 211 from an optically denser medium to an optically less dense medium, thus satisfying the total internal reflection condition of the polarized ray 300 in the first reflection region 211. This allows the polarized ray 300 to achieve total internal reflection in the first reflection region 211 without considering the refractive index of the third prism 4. The structure is simple and easy to implement.
[0143] When the third prism 4 and the first prism 2 are spaced apart at least at the position of the first reflection zone 211, the filling medium at the interval can be air or other media with a refractive index lower than that of the first prism 2. The specific setting can be determined according to actual needs and is not limited here.
[0144] In one specific embodiment, such as Figure 5 As shown, the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 has an incident angle at the second optical surface 22 that is greater than or equal to the critical angle for total internal reflection. This allows the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 to undergo total internal reflection on the second optical surface 22, thereby improving the utilization rate of the polarized light 300 and thus improving the optical efficiency of the optical module 10.
[0145] Furthermore, the second optical surface 22 includes a second reflective area 221 and a second transmissive area 222, which are arranged sequentially along a direction away from the display component 1. Polarized light 300 can be reflected by the second reflective area 221 towards the first optical surface 21, and polarized light 300 can exit or enter the first prism 2 through the second transmissive area 222. The second prism 3 is spaced apart from the first prism 2 at least at the position of the second reflective area 221.
[0146] In this embodiment, as Figure 5 As shown, this structure enables an air gap to be formed between the second prism 3 and the first prism 2 at least at the position of the second reflection region 221. Since the refractive index of the first prism 2 is greater than that of air, the refracted ray 300 enters the second reflection region 221 from an optically denser medium to an optically less dense medium, thereby satisfying the total internal reflection condition of the polarized ray 300 in the second reflection region 221. This allows the polarized ray 300 to achieve total internal reflection in the second reflection region 221 without considering the refractive index of the second prism 3. The structure is simple and easy to implement.
[0147] When the second prism 3 and the first prism 2 are spaced apart at least at the position of the second reflection zone 221, the filling medium at the interval can be air or other media with a refractive index lower than that of the first prism 2. The specific setting can be determined according to actual needs and is not limited here.
[0148] like Figure 5 As shown, the aforementioned polarization reflective layer 5 has a transmission axis. When the polarization direction of the polarized light 300 is parallel to the direction of the transmission axis of the polarization reflective layer 5, it can pass through the polarization reflective layer 5 and exit; otherwise, the polarized light 300 can be reflected by the polarization reflective layer 5. Specifically, the polarization reflective layer 5 can be disposed between the first transmission area 212 and the seventh optical surface 42, and the polarization direction of the polarized light 300 emitted by the display component 1 can be set perpendicular to the transmission axis of the polarization reflective layer 5, so that the polarized light 300 reflected by the second optical surface 22 to the first optical surface 21 and transmitted through the first transmission area 212 can be reflected by the polarization reflective layer 5.
[0149] In one specific embodiment, such as Figure 5 As shown, the optical module 10 also includes a phase retardation layer 6, which is disposed between the first prism 2 and the second prism 3. Specifically, the phase retardation layer 6 can be disposed between the second transmission region 222 and the sixth optical surface 32.
[0150] In this embodiment, as Figure 5 As shown, the phase retardation layer 6 is used to change the polarization state of the polarized light 300. The phase retardation layer 6 is disposed between the first prism 2 and the second prism 3, which can change the polarization state of the polarized light 300 that enters the first prism 2 after being reflected by the third optical surface 31. This causes the polarization direction of the polarized light 300 that is transmitted through the second transmission area 222 and the first transmission area 212 in sequence to be parallel to the direction of the transmission axis of the polarization reflection layer 5, so that the polarized light 300 can pass through the polarization reflection layer 5 and enter the third prism 4.
[0151] Furthermore, phase delay layer 6 is a quarter-wave plate.
[0152] like Figure 5As shown, the polarized light 300 reflected by the polarization reflection layer 5 passes through the first transmission region 212 and the second transmission region 222 sequentially before exiting the first prism 2. It can then pass through the phase retardation layer 6 into the second prism 3 and be reflected on the third optical surface 31. At least a portion of the light, after being reflected by the third optical surface 31, can re-enter the first prism 2 through the phase retardation layer 6. The quarter-wave plate, also known as a 45° phase retardation plate, rotates the polarization state of the polarized light 300 by 90° when it passes through twice, thus making the polarization direction of the polarized light 300 parallel to the transmission axis of the polarization reflection layer 5, allowing the polarized light 300 to pass through the polarization reflection layer 5 into the third prism 4.
[0153] For example, such as Figure 5 In the specific embodiment shown, the display component 1 emits polarized light 300, which is S-light, and the polarization reflective layer 5 is used to reflect the S-light and transmit the P-light. Here, the S-light is light whose vibration plane is perpendicular to the direction of light propagation, and the P-light is light whose vibration plane is parallel to the direction of light propagation. After entering the first prism 2, the polarized light 300 is reflected sequentially through the first reflection area 211 and the second reflection area 221 to the first transmission area 212 and then transmitted out. Polarization reflection occurs at the polarization reflection layer 5. The polarized light 300 reflected by the polarization reflection layer 5 can then sequentially pass through the first transmission area 212, the second transmission area 222, and the phase retardation layer 6 to enter the second prism 3 and be reflected at the third optical surface 31. At least part of the light can be reflected by the third optical surface 31 and then re-enter the first prism 2 through the phase retardation layer 6. The polarized light 300 is converted from S-light to P-light, so that the polarized light 300 can sequentially pass through the second transmission area 222, the first transmission area 212, and the polarization reflection layer 5 and then enter the third prism 4. In turn, the polarized light 300 can pass through the fourth optical surface 41 and enter the human eye to form a virtual image.
[0154] Please refer to Figure 6 , Figure 6 This is a schematic diagram of the structure of the display module provided in this application in another specific embodiment.
[0155] like Figure 6 As shown, in one specific embodiment, the optical module 10 may further include a first optical film layer 7a, which is attached to the first optical surface 21. At least a portion of the polarized light 300 emitted by the display component 1 toward the first optical surface 21 can be reflected by the first optical film layer 7a toward the second optical surface 22.
[0156] In this embodiment, as Figure 6As shown, by attaching a first optical film layer 7a to the first optical surface 21, at least a portion of the polarized light 300 emitted by the display component 1 toward the first optical surface 21 can be reflected by the first optical film layer 7a toward the second optical surface 22. This simplifies the manufacturing process, further reduces the manufacturing difficulty of the optical module 10, and lowers the incident angle requirement of the polarized light 300 emitted by the display component 1 on the first optical surface 21. It can also be adapted to the first prism 2 made of more materials and adjust the setting position of the display component 1, which is beneficial to improving the structural compactness of the optical module 10.
[0157] For example, the first optical film layer 7a can be a polarizing reflective film or a beam splitter, so that some of the polarized light 300 incident on the first optical surface 21 by the display component 1 can be reflected by the first optical film layer 7a to the second optical surface 22, thereby reducing the utilization of the polarized light 300, thereby reducing the brightness of the image, and making the display component 1 with higher brightness (e.g., the display component 1 with a high-brightness LCOS display) more suitable for the brightness range accepted by the human eye, thus improving the user experience.
[0158] For example, the first optical film layer 7a can also be a total reflection film, so that the polarized light 300 emitted by the display component 1 toward the first optical surface 21 can undergo total reflection through the first optical film layer 7a, thereby improving the utilization rate of the polarized light 300 by the display module 10, improving the imaging quality, and reducing the incident angle requirement of the polarized light 300 emitted by the display component 1 on the first optical surface 21 to meet total reflection. It can be adapted to the first prism 2 of more materials, and can also adjust the setting position of the display component 1, which is conducive to further improving the structural compactness of the optical module 10.
[0159] Of course, the first optical film layer 7a can also be other optical film layer structures with reflective properties. The specific structure can be set according to actual needs, and there are no restrictions here.
[0160] In one specific embodiment, such as Figure 6 As shown, the optical module 10 also includes a second optical film layer 7b, which is attached to the second optical surface 22. At least a portion of the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 can be reflected back to the first optical surface 21 by the second optical film layer 7b.
[0161] In this embodiment, as Figure 6As shown, by attaching a second optical film layer 7b to the second optical surface 22, at least a portion of the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 can be reflected back to the first optical surface 21 by the second optical film layer 7b. This simplifies the manufacturing process and reduces the incident angle requirement of the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 on the second optical surface 22. It can be adapted to the first prism 2 made of more materials and also reduces the manufacturing requirements of the first optical surface 21, further reducing the manufacturing difficulty of the optical module 10.
[0162] For example, the second optical film layer 7b can be a polarizing reflective film or a beam splitter, so that some of the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 can be reflected from the second optical film layer 7b back to the first optical surface 21, thereby reducing the utilization of the polarized light 300 and reducing the brightness of the image. This allows the display component 1 with higher brightness (e.g., a display component 1 with a high-brightness LCOS display) to better adapt to the brightness range acceptable to the human eye and improve the user experience.
[0163] For example, the second optical film layer 7b is a total reflection film, so that the partially polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 can undergo total internal reflection through the second optical film layer 7b, thereby improving the utilization rate of the polarized light 300 of the display module 10, improving the imaging quality, and reducing the incident angle requirement of the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 to meet total internal reflection. It can be adapted to the first prism 2 of more materials, and can also reduce the manufacturing requirements of the first optical surface 21, further reducing the manufacturing difficulty of the optical module 10.
[0164] Of course, the second optical film layer 7b can also be other optical film layer structures with reflective properties. The specific structure can be set according to actual needs, and there are no restrictions here.
[0165] Please refer to Figure 7 , Figure 7 This is a schematic diagram of the structure of the display module provided in this application in another specific embodiment.
[0166] Figure 7 As shown, in another specific embodiment, the optical module 10 further includes a first reflector 8, which is attached to the second reflective area 221. The polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 can undergo total internal reflection through the first reflector 8.
[0167] In this embodiment, as Figure 7As shown, by attaching the first reflector 8 to the second reflective area 221, the partially polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 can undergo total internal reflection through the first reflector 8, thereby improving the utilization rate of the polarized light 300 in the display module 10, improving the imaging quality, and the structure is simple and easy to implement. It can also reduce the incident angle requirement of the polarized light 300 reflected from the first optical surface 21 to the second optical surface 22 to meet total internal reflection on the second optical surface 22, can be adapted to the first prism 2 of more materials, and can also reduce the manufacturing requirements of the first optical surface 21, further reducing the manufacturing difficulty of the optical module 10.
[0168] The first reflector 8 can be a reflector or a prism with a reflective film, etc. The specific configuration can be set according to actual needs and is not limited here.
[0169] Please refer to Figure 8 , Figure 8 This is a schematic diagram of the structure of the display module provided in this application in another specific embodiment.
[0170] like Figure 8 As shown, when the second reflective area 221 is provided with the first reflector 8, or when the second prism 3 does not completely cover the second optical surface 22, the user cannot see the external environment through the area covered by the first reflector 8 or the area not covered by the second prism 3. The optical module 10 may also include a fourth prism 9b, which cooperates with the second prism 3 to cover the second optical surface 22. The surface of the fourth prism 9b facing away from the second optical surface 22 cooperates with the third surface 31 of the second prism 2 to form a smoothly transitioned curved surface structure, so that the overall structure of the optical module 10 is closer to the lens shape of glasses, thereby improving the user's wearing effect.
[0171] The fourth prism 9b can be glued to the second prism 3 or integrally formed. The specific configuration can be determined according to actual needs and is not limited here.
[0172] In addition, the material of the fourth prism 9b can be optical glass or plastic, etc., and the specific material can be set according to actual needs. There are no restrictions here.
[0173] Please refer to Figure 9 , Figure 9 This is a schematic diagram of the structure of the display module provided in this application in another specific embodiment.
[0174] In one specific embodiment, such as Figure 9 As shown, the second prism 3 covers the entire second reflection area 221, and the third prism 4 covers at least part of the first reflection area 211. Ambient light 400 can enter the human eye sequentially through the second prism 3, the first prism 2, and the third prism 4.
[0175] In this embodiment, as Figure 9 As shown, this structure can expand the visible area of the external environment that the user can see through the optical component 10, that is, the area shown by the ambient light 400 in the figure. It can also help to form the optical module 10 as a uniform arc-shaped sheet structure and ensure the appearance of the optical module 10 is integrated, so that the shape of the optical module 10 is closer to the shape of the lens of the glasses, thus improving the wearing effect of the user.
[0176] Please refer to Figure 10 , Figure 10 This is a schematic diagram of the structure of the display module provided in this application in another specific embodiment.
[0177] In one specific embodiment, the optical module 10 further includes a prism group 9a, which is disposed between the first prism 2 and the third prism 4. The prism group 9a includes at least one prism, and a polarizing reflection layer 5 is disposed on the surface of the prism group 9a near the third prism 4.
[0178] In this embodiment, as Figure 10 As shown, the arrangement of prism group 9a can increase the design freedom of optical module 10, and also increase the number of optical surfaces through which polarized light 300 passes, thereby further improving the aberration correction effect, improving the imaging quality of optical module 10, and reducing the volume of first prism 2, thereby reducing the manufacturing difficulty of first prism 2.
[0179] Among them, the prism group 9a can be glued to the first optical surface 21 of the first prism 2 to further improve the structural compactness of the optical module 10.
[0180] The same or similar parts between the various embodiments in this specification can be referred to mutually. In particular, the device embodiments and terminal embodiments are basically similar to the method embodiments, so the description is relatively simple, and the relevant parts can be referred to the description in the method embodiments.
[0181] The above descriptions are merely specific implementations of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application. Therefore, the protection scope of the embodiments of this application should be determined by the protection scope of the claims.
Claims
1. An optical module, characterized in that, include: The display component includes a light-emitting surface for emitting polarized light; A first prism is disposed on the light-emitting surface side of the display component, and the first prism includes a first optical surface and a second optical surface; A polarizing reflective layer is disposed on the side of the first prism having the first optical surface; The second prism is disposed on the side of the first prism having the second optical surface, and the second prism includes a third optical surface disposed on the side away from the second optical surface; The third prism is disposed on the side of the polarizing reflective layer opposite to the first optical surface, and the third prism includes a fourth optical surface disposed on the side away from the first optical surface; The polarized light emitted by the display component can be reflected sequentially by the first optical surface, the second optical surface, the polarization reflection layer, and the third optical surface, and then pass through the fourth optical surface into the human eye. The fourth optical surface and the third optical surface are curved surfaces with the same shape.
2. The optical module according to claim 1, characterized in that, The first prism further includes a fifth optical surface, which is disposed on a side close to the display component and connected to the first optical surface and the second optical surface; At least two of the fifth optical surface, the first optical surface, the second optical surface, and the third optical surface are freeform surfaces.
3. The optical module according to any one of claims 1 or 2, characterized in that, The first optical surface is a freeform surface.
4. The optical module according to any one of claims 1 to 3, characterized in that, The polarized light rays incident on the first optical surface via the display component have an incident angle at the first optical surface that is greater than or equal to the critical angle for total internal reflection.
5. The optical module according to any one of claims 1 to 4, characterized in that, The first optical surface includes a first reflective area and a first transmissive area, which are arranged sequentially along a direction away from the display component; Polarized light can be reflected by the first reflection area to the second optical surface, and can exit or enter the first prism through the first transmission area. The third prism is spaced apart from the first prism at least at the position of the first reflection zone.
6. The optical module according to any one of claims 1 to 5, characterized in that, The polarized light rays reflected from the first optical surface to the second optical surface have an incident angle at the second optical surface that is greater than or equal to the critical angle for total internal reflection.
7. The optical module according to any one of claims 1 to 6, characterized in that, The second optical surface includes a second reflective area and a second transmissive area, which are arranged sequentially along a direction away from the display component; Polarized light can be reflected by the second reflection area toward the first optical surface, and then exit through the second transmission area or enter the first prism; The second prism is spaced apart from the first prism at least at the location of the second reflection zone.
8. The optical module according to claim 7, characterized in that, The optical module further includes a first reflector, which is attached to the second reflective area; Polarized light rays reflected from the first optical surface to the second optical surface can undergo total internal reflection by the first reflector.
9. The optical module according to any one of claims 1 to 8, characterized in that, The optical module further includes a first optical film layer, which is attached to the first optical surface; At least a portion of the polarized light rays incident on the first optical surface via the display component can be reflected by the first optical film layer to the second optical surface.
10. The optical module according to claim 9, characterized in that, The first optical film layer is a total reflection film, a polarizing reflection film, or a beam splitting film.
11. The optical module according to any one of claims 1 to 10, characterized in that, The optical module further includes a second optical film layer, which is attached to the second optical surface; At least a portion of the polarized light reflected from the first optical surface to the second optical surface can be reflected back to the first optical surface by the second optical film layer.
12. The optical module according to claim 11, characterized in that, The second optical film layer is a total reflection film, a polarizing reflection film, or a beam splitting film.
13. The optical module according to claim 11, characterized in that, The second prism covers at least part or all of the second reflective area; The third prism covers at least a portion of the first reflective area; Ambient light can enter the human eye in sequence through the second prism, the first prism, and the third prism.
14. The optical module according to any one of claims 1 to 13, characterized in that, The optical module further includes a phase retardation layer, which is disposed between the first prism and the second prism.
15. The optical module according to claim 14, characterized in that, The phase delay layer is a quarter-wave plate.
16. The optical module according to any one of claims 1 to 15, characterized in that, The second prism further includes a sixth optical surface, which is disposed on a side close to the second optical surface; The sixth optical surface has the same surface shape as the second optical surface.
17. The optical module according to any one of claims 1 to 16, characterized in that, The third prism also includes a seventh optical surface, which is disposed on the side close to the first optical surface; The seventh optical surface has the same surface shape as the first optical surface.
18. The optical module according to any one of claims 1 to 17, characterized in that, The optical module further includes a prism group, which is disposed between the first prism and the third prism, and the prism group includes at least one prism. The polarizing reflective layer is provided on the surface of the prism group near the third prism.
19. An electronic device, characterized in that, The electronic device includes a frame and an optical module as described in any one of claims 1 to 18, the optical module being mounted on the frame.