Imaging module and head-mounted display device

Abstract

An imaging module and a head-mounted display device. The imaging module comprises: a display screen (1), the light rays emitted from different positions of the display screen (1) including main light rays (A1, B1, C1) located at the center, and the main light rays (A1, B1, C1) all being emitted from the display screen (1) at a predetermined angle ranging from 85° to 95°; and an imaging lens group, the imaging lens group being arranged in the emergent light direction of the display screen (1), wherein when the display screen (1) moves in the normal direction of the screen surface, the main light rays (A1, B1, C1) all pass through the center of the exit pupil position.

Description

Imaging modules and head-mounted display devices Technical Field

[0001] This application relates to the field of display technology, and more specifically, to an imaging module and a head-mounted display device. Background Technology

[0002] Traditional zoom-based augmented reality (AR) modules experience a change in their field of view (FOV) during focal length adjustment, leading to variations in image distortion. A common approach to address this issue is to use subsequent software algorithms to correct these distortions.

[0003] In view of this, a new technical solution is needed to solve the above-mentioned technical problems. Summary of the Invention

[0004] The purpose of this application is to provide a new technology solution for an imaging module and a head-mounted display device.

[0005] In a first aspect, embodiments of this application provide an imaging module. The imaging module includes:

[0006] The display screen emits light from different positions, including a main light ray at the center. The main light rays are emitted from the display screen at a predetermined angle, and the predetermined angle range is 85° to 95°.

[0007] An imaging lens group, wherein the imaging lens group is disposed in the light-emitting direction of the display screen;

[0008] When the display screen moves along the normal direction of the screen surface, the main light rays all pass through the central region of the exit pupil position.

[0009] Optionally, the imaging module includes an aperture stop located at the exit pupil position, and all the main rays pass through the center of the aperture stop.

[0010] Optionally, the predetermined angle is 90°.

[0011] Optionally, the adjustment range of the virtual image distance of the imaging module is 0D to 7D.

[0012] Optionally, the size range of the display screen is 0.3 inches to 1.03 inches.

[0013] Optionally, the display screen is an OLED screen.

[0014] Optionally, a polarizing film is disposed between the display screen and the imaging lens group, and the imaging lens group includes a polarizing reflective film;

[0015] The transmission axis of the polarizing film is parallel to the reflection axis of the polarizing reflective film.

[0016] Optionally, the imaging lens group includes: a first lens having a front surface near the exit pupil position and a rear surface away from the exit pupil position;

[0017] The front surface of the first lens is used for total internal reflection of light received from the outside, and the front surface of the first lens transmits light reflected from the rear surface of the first lens.

[0018] Optionally, the principal ray after total internal reflection by the front surface of the first lens is transmitted to the rear surface of the first lens, and the exit angle of the principal ray after reflection by the rear surface of the first lens is less than or equal to 5°.

[0019] Optionally, the imaging lens group further includes a second lens located on the light-incident side of the first lens, the second lens transmitting the light transmitted from the display screen through the upper surface of the first lens into the first lens.

[0020] Optionally, the imaging lens group further includes a third lens, wherein the rear surface of the first lens and the front surface of the third lens are cemented together to form a cemented lens group with zero optical power, and the cemented lens group is configured to transmit ambient light.

[0021] Secondly, embodiments of this application provide a head-mounted display device. The head-mounted display device includes:

[0022] The imaging module as described in the first aspect;

[0023] The imaging module is disposed within the housing.

[0024] According to the embodiments of this application, the main light rays emitted from different positions of the display screen are emitted at a preset angle, that is, the main light rays emitted from different positions of the display screen are emitted in a parallel or substantially parallel manner. During the process of the display screen moving along the normal direction of the screen surface, the incident angle of the main light rays emitted from different positions of the display screen onto the imaging lens group remains unchanged. This ensures that the field of view and distortion of the imaging module do not change during the movement of the display screen, thus ensuring the consistency of imaging quality.

[0025] Other features and advantages of this specification will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of this specification and, together with their description, serve to explain the principles of this specification.

[0027] Figure 1 shows the architecture diagram of the imaging module provided in the embodiment of this application.

[0028] Figure 2 shows a schematic diagram of the zoom of the imaging module provided in an embodiment of this application.

[0029] Figure 3 shows the modulation transfer function (MTF) curve of the imaging module provided in this embodiment at 450 nm.

[0030] Figure 4 shows the modulation transfer function (MTF) curve of the imaging module provided in this embodiment at 540 nm.

[0031] Figure 5 shows the modulation transfer function (MTF) curve of the imaging module provided in this embodiment at 610 nm.

[0032] Explanation of reference numerals in the attached diagram: 1. Display screen; 10. Polarizing film; 21. First lens; 22. Second lens; 23. Third lens; 24. Polarizing reflective film; 3. Aperture stop. Detailed Implementation

[0033] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0034] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0035] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0036] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0037] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0038] This application provides an imaging module. Referring to Figures 1 and 2, the imaging module includes: a display screen 1, wherein light emitted from different positions of the display screen 1 includes a central main light ray, all of which are emitted from the display screen 1 at a predetermined angle, the predetermined angle ranging from 85° to 95°; and an imaging lens group disposed in the light emission direction of the display screen 1.

[0039] When the display screen 1 moves along the normal direction of the screen surface, the main light rays all pass through the center of the exit pupil position.

[0040] The imaging process of the imaging module is as follows: the display screen 1 of the imaging screen emits light, which is directed towards the imaging lens group. The imaging lens group is used to transmit the light from the display screen 1 to the human eye at the exit pupil position to form an image.

[0041] Each pixel on display screen 1 is a light-emitting unit. The light emitted from the light-emitting unit forms a conical diffused light beam. The light beam includes a main light beam and edge light beams. The edge light beams are located around the main light beams and have a weaker light intensity. The main light beam accounts for most of the light intensity of the diffused light beams. Controlling the emission angle of the main light beam is equivalent to controlling the emission angle of all the light beams on display screen 1. Therefore, ensuring the emission angle of the main light beam ensures the emission angle of the entire light beam.

[0042] The imaging lens group is located in the light-emitting direction of the display screen 1. The function of the imaging lens group is to amplify and resolve the light. The light-emitting surface area of ​​the display screen 1 is relatively small. In order to ensure that the user obtains a magnified display image, the light needs to be amplified. The imaging lens group ensures that the user obtains a magnified image that can be recognized. The imaging lens can be a single lens or a combination of multiple lenses.

[0043] In this embodiment, the emission angle of the main light rays emitted from different positions of the display screen 1 is within 90°±5°. This can also be understood as: the emission angle of the light rays emitted from different positions of the display screen 1 is within the range of 90°±5°, and the light rays emitted from different positions of the display screen 1 are parallel or substantially parallel.

[0044] For example, A, B, and C are light-emitting units at different positions on the display screen 1, A1 is the main light emitted by light-emitting unit A, B1 is the main light emitted by light-emitting unit B, and C1 is the main light emitted by light-emitting unit C.

[0045] As the display screen 1 moves along the normal direction of the screen surface, the imaging module is zoomed. The main light rays A1, B1, and C1 emitted by the light-emitting units at different positions on the display screen 1 are all emitted from the display screen 1 at a preset angle. When the display screen 1 moves along the normal direction of the screen surface, the positions of the light-emitting units A, B, and C on the display screen 1 remain unchanged, and the emission angles of the main light rays A1, B1, and C1 emitted by them remain basically unchanged. Even if the emission angles of the main light rays A1, B1, and C1 change, the range of emission angles before and after the change is controlled within a small range (within 10°, or even within 5°).

[0046] Since the main rays A1, B1, and C1 emerge from the display screen 1 at an exit angle of 90°±5°, and the display screen 1 moves along the normal direction of its surface, the incident angles of the main rays A1, B1, and C1 entering the imaging lens group remain essentially unchanged (even if the incident angles of the main rays A1, B1, and C1 entering the imaging lens group change due to the change in their exit angles, this change range is relatively small). Thus, the transmission paths of the main rays A1, B1, and C1 within the imaging lens group remain essentially unchanged. That is, no matter where the display screen 1 moves, the main rays A1, B1, and C1 emitted from the display screen can enter the human eye from the center of the exit pupil position, meaning that the incident angles of the main rays A1, B1, and C1 entering the human eye remain essentially unchanged.

[0047] Therefore, when the display screen 1 moves along the normal direction of the screen surface, the emission angle of the main light ray corresponding to the same light-emitting unit of the display screen 1 remains basically unchanged, and the incident angle entering the human eye also remains basically unchanged. Thus, the FOV and distortion of the imaging module remain basically unchanged.

[0048] In this embodiment, the main light rays emitted from different positions of the display screen 1 are emitted at a preset angle, that is, the main light rays emitted from different positions of the display screen 1 are emitted in a parallel or substantially parallel manner. During the process of the display screen 1 moving along the normal direction of the screen surface, the incident angle of the main light rays emitted from different positions of the display screen 1 onto the imaging lens group remains unchanged. This ensures that the field of view and distortion of the imaging module do not change during the movement of the display screen 1, thus ensuring the consistency of imaging quality.

[0049] In one embodiment, referring to Figures 1 and 2, the imaging module includes an aperture stop 3, which is located at the exit pupil position, and the main rays all pass through the center of the aperture stop 3.

[0050] In this embodiment, the display screen 1 can move along the normal direction of its surface. Therefore, the design of the aperture stop 3 at the exit pupil position ensures that the main light ray passes accurately through the center of the aperture stop 3 regardless of the screen's position. This helps maintain the stability and consistency of the imaging module under different screen positions.

[0051] In a preferred embodiment, the predetermined angle is 90°.

[0052] In this embodiment, the main light rays emitted from different positions of the display screen 1 are all emitted perpendicular to the display screen 1, and the display screen 1 moves along the normal direction of the screen surface between positions 1-1 and 1-2.

[0053] The main rays A1, B1, and C1 emitted by the light-emitting units A, B, and C on the display screen 1 are perpendicular to the display screen 1. Therefore, when the display screen 1 moves along the normal direction of the light-emitting surface, the positions of the light-emitting units A, B, and C on the display screen 1 remain unchanged, and the light-emitting angles of the main rays A1, B1, and C1 remain unchanged. Thus, the transmission path of the main rays A1, B1, and C1 in the imaging lens group remains unchanged, and the incident angle entering the human eye remains unchanged.

[0054] Therefore, when the display screen 1 moves along the normal direction of the screen's light-emitting surface, the light-emitting angle of the principal ray corresponding to the same pixel on the screen surface remains unchanged, and the incident angle entering the human eye also remains unchanged. Thus, the FOV and distortion of the imaging module remain unchanged.

[0055] In one embodiment, the adjustment range of the virtual image distance of the imaging module is 0D to 7D.

[0056] Specifically, the imaging module is a variable-focus imaging module. The way to achieve zooming of the imaging module is: the display screen 1 moves along the normal direction of its light-emitting surface to achieve focusing of the imaging module.

[0057] The movement of display screen 1 along the normal direction of the screen surface means that display screen 1 has the ability to move in a direction perpendicular to the screen surface (i.e., the normal direction). Here, it refers to the ability of display screen 1 to move forward or backward to achieve the purpose of focusing.

[0058] During the movement of display screen 1 along a direction perpendicular to the screen surface, the VID adjustment range is from 0 to 7 diopters (D). In this embodiment, diopters are used to describe the focusing range of the imaging module. The imaging module can focus over a fairly large range to adapt to different screen distances and imaging requirements.

[0059] In one embodiment, the size of the display screen 1 ranges from 0.3 inches to 1.03 inches.

[0060] In this embodiment, by limiting the size of the display screen 1, it can be seen that the imaging module's display screen 1 is a relatively small screen. On a smaller screen size, a more detailed image display can be achieved by increasing the resolution and pixel density. This helps to improve the clarity and detail of the image, allowing users to have a good visual experience even on a smaller screen.

[0061] In one embodiment, the display screen 1 is an OLED screen.

[0062] In this embodiment, the type of display screen 1 is defined as an OLED screen, so that the emission angle of the main light emitted from different positions of the display screen 1 is limited to the range of 85° to 95°.

[0063] Specifically, the light-emitting layer design of OLEDs (Organic Light Emitting Diodes) ensures isotropic light emission, meaning light is emitted uniformly in all directions. However, to control the direction of light and direct it forward, OLED screens typically employ special optical designs, such as microlens arrays or light guide structures. This design allows light to propagate primarily along a direction perpendicular to the screen during emission, thus ensuring that the emission angle of the main light rays emanating from different positions on the display screen is within a preset range. The imaging module architecture is a telecentric image-side architecture.

[0064] In one embodiment, a polarizing film 10 is disposed between the display screen 1 and the imaging lens group, and the imaging lens group includes a polarizing reflective film 24.

[0065] The transmission axis of the polarizing film 10 is parallel to the reflection axis of the polarizing reflective film 24.

[0066] In this embodiment, the transmission axis of the polarizing film 10 and the reflection axis of the polarizing reflective film 24 are designed to be parallel. This means that light rays transmitted from the light-emitting side of the display screen 1, conforming to the transmission axis of the polarizing film 10, are incident on the polarizing reflective film 24 and reflected back to the front surface of the first lens 21, without changing the polarization direction of the light rays throughout the process. That is, the polarization direction of the light rays allowed to be transmitted by the polarizing film 10 is consistent with the polarization direction of the light rays allowed to be reflected by the polarizing reflective film 24.

[0067] Due to the parallel arrangement of the polarizing film 10 and the polarizing reflective film 24, only light rays conforming to a specific polarization direction can propagate in the optical module. This helps reduce stray and reflected light interference with the image, thereby improving image contrast.

[0068] For example, a polarizing reflective film 24 may be provided on the rear surface of the first lens 21, or when the first lens 21 and the third lens 23 are cemented together, a polarizing reflective film 24 may be provided between the first lens 21 and the third lens 23, or a polarizing reflective film 24 may be provided on the front surface of the third lens 23.

[0069] In a specific embodiment, referring to Figures 1 and 2, the architecture of the imaging lens group is defined. The imaging lens group must meet the following condition: after receiving the image light rays from the display screen 1, the imaging lens group transmits the image light rays, and all the main rays transmitted through the imaging lens group can pass through the center of the aperture 3. Thus, as the display screen 1 moves along the optical axis of its emitted main rays, the field of view of the entire imaging module does not change significantly, and the image distortion formed by the imaging module is minimal.

[0070] Specifically, the imaging lens group includes: a first lens 21, the first lens 21 having a front surface close to the exit pupil position and a rear surface away from the exit pupil position;

[0071] The front surface of the first lens 21 is used for total internal reflection of light received from the outside, and the front surface of the first lens 21 transmits light reflected from the rear surface of the first lens 21.

[0072] In this embodiment, the imaging lens group mainly includes a first lens 21, which has two main surfaces: a front surface near the exit pupil and a rear surface away from the exit pupil. When the imaging module is applied to an AR display device, the front surface of the first lens 21 is positioned close to the human eye, and the rear surface of the first lens 21 is positioned away from the human eye.

[0073] The front surface of the first lens 21 is designed to perform total internal reflection of light received from the outside. This means that when light is incident on the front surface of the first lens 21 at a specific angle, the light will be completely reflected back into the first lens 21 without penetrating the lens or causing significant refraction. This provides a basis for the imaging lens group to deflect light, allowing the light to propagate and be processed within the imaging lens group along a predetermined path, thereby improving image quality. In other words, in this embodiment, the imaging lens group transmits image light through optical path folding (deflection).

[0074] For example, the source of external light may be image light emitted from the display screen 1, or light transmitted to the inside of the first lens 21 by other lenses.

[0075] In addition to total internal reflection, the front surface of the first lens 21 can also transmit light reflected from the rear surface of the first lens 21. This means that after a series of reflections inside the imaging lens group, the light finally reaches the front surface of the first lens 21, where it is transmitted and enters the human eye.

[0076] The rear surface of the first lens 21 is designed to work in conjunction with the front surface to reflect the image light.

[0077] Therefore, in this embodiment, the first lens 21, through a combination of total internal reflection and transmission, can maximize the utilization of light and reduce light loss. Furthermore, the first lens 21 can precisely control the propagation path of light, contributing to a clearer image display and reducing image distortion and blurring.

[0078] In one specific embodiment, to further ensure that the main light rays emitted from different positions of the display screen 1 can pass through the center of the exit pupil position (aperture stop 3), the imaging lens group includes a first lens 21. The first lens 21 is the lens closest to the exit pupil position. After transmission, the main light rays emitted from different positions of the display screen 1 finally enter the human eye after being transmitted through the front surface of the first lens 21. Therefore, this embodiment limits the exit angle of the main light rays transmitted to the rear surface of the first lens 21. According to the principle of light reflection, the light rays reflected by the rear surface of the first lens 21 are transmitted through the front surface of the first lens 21 and can pass through the center of the exit pupil position (aperture stop 3).

[0079] Specifically, referring to Figures 1 and 2, the principal ray after total reflection by the front surface of the first lens 21 is transmitted to the rear surface of the first lens 21, and the exit angle of the principal ray after reflection by the rear surface of the first lens 21 is less than or equal to 5°.

[0080] In this embodiment, the main light emitted from the display screen 1 is projected onto the front surface of the first lens 21 at an incident angle greater than or equal to the critical angle, and is then totally reflected by the front surface of the first lens 21.

[0081] Next, the total internally reflected principal ray is transmitted to the rear surface of the first lens 21. The total internally reflected principal ray is incident on the rear surface of the first lens 21 at an angle of incidence less than or equal to 5°. The rear surface of the first lens 21 can reflect the transmitted light by attaching a polarizing reflective film 24. According to the principle of light reflection, the exit angle of the principal ray reflected by the rear surface of the first lens 21 is also less than or equal to 5°. With this design, the direction of the principal ray emitted from different positions on the display screen 1 after two reflections (once on the front surface and once on the rear surface) is precisely controlled, allowing it to pass through the front surface and point towards the center of the aperture stop 3. This design further ensures that the imaging module has a telecentric image structure. As the display screen 1 moves along the perpendicular direction of its luminous surface, the changes in the FOV and distortion of the imaging module are very small, ensuring consistent image quality.

[0082] It should be noted that by precisely controlling the direction of light reflection on the rear surface, as well as the shape, position, and relative relationship between the front and rear surfaces, it can be ensured that the reflected principal ray can pass through the front surface again and accurately point to the center of aperture 3. This design is also commonly used to ensure the symmetry of the optical system, reduce aberrations, and optimize the focusing or imaging performance of light.

[0083] Further referring to Figures 1 and 2, the imaging lens group also includes a second lens 22, which is located on the light-incident side of the first lens 21. The second lens 22 transmits the light transmitted from the display screen 1 through the upper surface of the first lens 21 into the first lens 21.

[0084] In this embodiment, in order to further ensure the imaging quality of the imaging lens group, for example, in order to improve the MTF value of the imaging lens group, a second lens 22 is provided on the incident light side of the first lens group 21.

[0085] Specifically, the first lens 21 is a prism, which includes a front surface near the exit pupil, a rear surface away from the exit pupil, and an upper surface connected to the front and rear surfaces. The second lens 22 is actually located between the upper surface of the first lens 21 and the display screen 1.

[0086] The main function of the second lens 22 is to effectively transmit the light transmitted from the display screen 1 through the upper surface of the first lens 21 into the interior of the first lens 21. This requires the second lens 22 to have specific optical characteristics, such as appropriate focal length and curvature, to ensure that the light can propagate in the expected manner.

[0087] For example, when the second lens 22 is properly positioned between the screen and the first lens 21, the second lens 22 can further focus, diffuse, or adjust the direction of light emitted from the screen. This adjustment helps optimize the propagation path of the light, reduce aberrations, and thus improve the contrast and sharpness of the image.

[0088] Furthermore, referring to Figures 1 and 2, the imaging lens group further includes a third lens 23, wherein the rear surface of the first lens 21 and the front surface of the third lens 23 are cemented together to form a cemented lens group with zero optical power, and the cemented lens group is configured to transmit ambient light.

[0089] When the imaging module is applied to an AR display device, the AR display device can simultaneously project virtual images and real-world images into the human eye. This requires the imaging module to not only transmit the image light emitted from the display screen 1, but also to transmit ambient light.

[0090] In this embodiment, the imaging lens group includes a third lens 23, and the cemented lens group formed by cementing the third lens 23 and the first lens 21 together is used to transmit ambient light.

[0091] Since the overall optical power of the cemented lens group is zero, zero optical power means that the cemented lens group has no converging or diverging effect on light rays; that is, ambient light rays retain their original direction after passing through the cemented lens group. This helps to maintain the original proportions and shape of the image, avoiding distortion or deformation.

[0092] Furthermore, the imaging lens assembly also needs to transmit the image light emitted from the display screen 1. When the first lens 21 and the third lens 23 are cemented together, a polarizing reflective film 24 can be provided on the cemented surface of the first lens 21 and the third lens 23. This polarizing reflective film 24 can reflect the image light emitted from the display screen 1, and it can also project ambient light. Thus, when the display screen 1 emits light, this light does not pass through the third lens 23; that is, the light emitted from the display screen 1 is not affected by the third lens 23 (or is minimally affected), but is transmitted to the final observation or imaging position through other paths (such as directly through the front surface of the first lens 21). In this way, by cementing the rear surface of the first lens 21 and the front surface of the third lens 23 to form a cemented lens assembly with zero optical power, and by specifically configuring the third lens 23 not to transmit light emitted from the screen, this imaging lens assembly can achieve effective transmission of ambient image light and interference-free processing of screen light.

[0093] For example, the third lens 23 is a prism.

[0094] In one specific embodiment, the imaging module includes a display screen 1, with a polarizing film 10 disposed on one side of the display screen 1. The imaging lens group includes a first lens 21, a second lens 22, and a third lens 23, wherein the first lens 21 and the third lens 23 are cemented together, and a polarizing reflection film 24 is disposed on the cementing surface of the first lens 21 and the third lens 23. The imaging module also includes an aperture stop 3. Table 1 shows the structural parameters of the imaging module.

[0095] Table 1:

[0096] Figures 3, 4, and 5 show the modulation transfer function (MTF) curves of the AR module at 450nm, 540nm, and 610nm, respectively.

[0097] As can be seen from the figures, at a spatial frequency of 15 lp / mm, referring to Figure 3, at a wavelength of 450 nm, the MTF value is higher than 0.7; referring to Figure 4, at a wavelength of 540 nm, the MTF value is higher than 0.7; and referring to Figure 5, at a wavelength of 610 nm, the MTF value is higher than 0.7.

[0098] Secondly, embodiments of this application provide a head-mounted display device. The head-mounted display device includes:

[0099] The imaging module as described in the first aspect;

[0100] The imaging module is disposed within the housing.

[0101] In this embodiment, the housing provides a mounting space to support the imaging module, which is housed within the housing. Exemplarily, the head-mounted display device can be AR glasses or an AR head-mounted device.

[0102] The above embodiments mainly describe the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity, they will not be elaborated here.

[0103] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. An imaging module, characterized in that, include: The display screen (1) emits light from different positions, including the main light ray at the center. The main light ray is emitted from the display screen (1) at a predetermined angle, and the predetermined angle range is 85° to 95°. An imaging lens group is disposed in the light-emitting direction of the display screen (1); When the display screen (1) moves along the normal direction of the screen surface, the main rays all pass through the center of the exit pupil position.

2. The imaging module according to claim 1, characterized in that, The imaging module includes an aperture stop (3), which is located at the exit pupil position, and the main rays all pass through the center of the aperture stop (3).

3. The imaging module according to claim 1, characterized in that, The predetermined angle is 90°.

4. The imaging module according to claim 1, characterized in that, The adjustment range of the virtual image distance of the imaging module is 0D to 7D.

5. The imaging module according to claim 1, characterized in that, The size range of the display screen (1) is 0.3 inches to 1.03 inches.

6. The imaging module according to claim 1, characterized in that, The display screen (1) is an OLED screen.

7. The imaging module according to claim 1, characterized in that, A polarizing film (10) is disposed between the display screen (1) and the imaging lens group, and the imaging lens group includes a polarizing reflective film (24); The transmission axis of the polarizing film (10) is parallel to the reflection axis of the polarizing reflective film (24).

8. The imaging module according to any one of claims 1-7, characterized in that, The imaging lens group includes: a first lens (21), the first lens (21) having a front surface close to the exit pupil position and a rear surface away from the exit pupil position; The front surface of the first lens (21) is used for total internal reflection of light received from the outside, and the front surface of the first lens (21) transmits light reflected from the rear surface of the first lens (21).

9. The imaging module according to claim 8, characterized in that, The principal ray after total reflection by the front surface of the first lens (21) is transmitted to the rear surface of the first lens (21), and the exit angle of the principal ray after reflection by the rear surface of the first lens (21) is less than or equal to 5°.

10. The imaging module according to claim 8, characterized in that, The imaging lens group further includes a second lens (22), which is located on the light-incident side of the first lens (21). The second lens (22) transmits the light transmitted from the display screen (1) through the upper surface of the first lens (21) into the first lens (21).

11. The imaging module according to claim 10, characterized in that, The imaging lens group further includes a third lens (23), wherein the rear surface of the first lens (21) and the front surface of the third lens (23) are cemented together to form a cemented lens group with zero optical power, and the cemented lens group is configured to transmit ambient light.

12. A head-mounted display device, characterized in that, The head-mounted display device includes: The imaging module as described in any one of claims 1-11; The imaging module is disposed within the housing.

Images