Optical system and head-mounted display device

Abstract

The embodiment of the utility model discloses an optical system and head-mounted display equipment. According to the specific implementation mode, the device comprises a support, an image source, an optical assembly, a lens component and a check block, the image source is arranged on the support, the optical assembly comprises a first prism and a second prism, the first prism is provided with a first surface, a second surface and a third surface, the first surface is arranged close to the image source, and the third surface is arranged close to the lens component; the second prism is provided with a first surface and a second surface, the first surface is close to an eye box of the optical system, the second surface is attached to the second surface of the first prism, and the stop block covers the part, exceeding the lens component, of the third surface of the first prism. Light emitted by the image source enters from the first surface of the first prism, is totally reflected for at least one time in the first prism and then exits to the lens component from the third surface of the first prism, and the light reflected by the lens component passes through the first prism again and then enters the second prism. And the light is emitted to an eye box of the optical system after passing through the second surface of the second prism and the first surface of the second prism.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of optical imaging technology, and in particular, to an optical system and a head-mounted display device. BACKGROUND

[0002] At present, the head-mounted display device is applied more and more widely. The head-mounted display device can be used for content display. For example, the head-mounted display device can be used for displaying movie pictures, game pictures, web pages and the like. The optical system is an important component of the head-mounted display device. SUMMARY

[0003] Embodiments of the present disclosure provide an optical system and a head-mounted display device.

[0004] In order to achieve the above-mentioned purpose, the present disclosure provides the following technical solutions:

[0005] In one aspect, the present disclosure provides an optical system, comprising: a support, an image source, an optical assembly, a lens component and a stop block, the image source is arranged on the support, the optical assembly is arranged on the support, the optical assembly comprises the lens component, a first prism and a second prism, the first prism has a first surface, a second surface and a third surface, the first surface of the first prism is close to the image source, the third surface of the first prism is close to the lens component, the second prism has a first surface and a second surface, the first surface of the second prism is close to an eyebox of the optical system, the second surface of the second prism is attached to the second surface of the first prism, the stop block is connected to the support, the stop block is located at the top of the lens component and covers the part of the third surface of the first prism beyond the lens component, the light emitted by the image source is incident from the first surface of the first prism, after at least one total reflection in the first prism, the light is emitted from the third surface of the first prism to the lens component, the reflected light of the lens component passes through the first prism again, and is emitted to the eyebox of the optical system through the second surface of the second prism and the first surface of the second prism.

[0006] In another aspect, the present disclosure provides a head-mounted display device, comprising a frame structure and the optical system described above, the optical system is mounted on the frame structure.

[0007] The technical solutions of the present disclosure are described in further detail below by means of the drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0008] The accompanying drawings, which form a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0009] The present disclosure can be more clearly understood and appreciated from the following detailed description, taken in conjunction with the accompanying drawings, in which:

[0010] Figure 1A cross-sectional view of the optical system provided by the embodiment of the present disclosure is shown (no section lines are shown for clarity of expression);

[0011] Figure 2 A front view of the optical system provided by the embodiment of the present disclosure is shown;

[0012] Figure 3 A structural schematic diagram of a first prism of a lens component of the optical system provided by the embodiment of the present disclosure is shown;

[0013] Figure 4 A structural schematic diagram of a bracket of the optical system provided by the embodiment of the present disclosure is shown;

[0014] Figure 5 A schematic diagram showing that the stop block of the optical system provided by the embodiment of the present disclosure is located outside a preset field of view range.

[0015] In the figure, 1, bracket; 11, first bracket part; 111, first mounting port; 112, shielding table; 113, groove; 12, second bracket part; 13, third mounting port; 2, image source; 3, optical assembly; 31, first lens; 32, first prism; 321, first surface of the first prism; 322, second surface of the first prism; 323, third surface of the first prism; 324, first outer convex part; 33, second lens; 331, second outer convex part; 34, second prism; 341, first surface of the second prism; 342, second surface of the second prism; 35, step; 4, stop block; 41, recessed groove; 5, gap; 6, third lens; 7, eyebox.

[0016] It should be noted that the drawings and the written description are not intended to limit the scope of the concept of the present disclosure in any way, but to illustrate the concept of the present disclosure to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments will be described clearly and completely below with reference to the drawings in the embodiments of the present disclosure. The following embodiments are used to illustrate the present disclosure, but not to limit the scope of the present disclosure.

[0018] In the description of the present disclosure, it should be noted that the terms “upper”, “lower”, “inner”, “outer” and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the devices referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0019] In the description of the present disclosure, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting" should be understood in a broad sense, for example, can be fixedly connected, or detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances.

[0020] Exemplary summary

[0021] The head-mounted display device can also be referred to as a head-mounted display (HMD) or a head-mounted display. The head-mounted display device can be used to realize augmented reality (AR) effect, virtual reality (VR) effect, mixed reality (MR) effect, etc. The head-mounted display device can be in the form of smart glasses, a helmet, etc.

[0022] The optical system is an important component of the head-mounted display device. The optical system can also be referred to as an optical machine. The optical system can be used to emit light of a display picture of the head-mounted display device, and process the light so as to project the light to the eyes of a user wearing the head-mounted display device, thereby enabling the user to see the display picture. Therefore, in order to ensure the user's experience, it is necessary to reasonably design the optical system.

[0023] Exemplary structure

[0024] Figure 1 A cross-sectional view of an optical system provided by some embodiments of the present disclosure is shown; Figure 2 A front view of an optical system provided by an embodiment of the present disclosure is shown. The optical system can include a support 1, an image source 2, an optical assembly 3, and a lens component. The image source 2 is disposed on the support 1, and the optical assembly 3 is disposed on the support 1, which can be used to support the image source and the optical assembly 3. The optical assembly 3 is an assembly for serving an optical path, for example, which can transmit image light emitted by the image source 2 into the user's eyes. The optical assembly can be a lens, a prism, and a lens, etc. For example, the optical assembly can include a lens component, a first prism 32, and a second prism 34. The form of the lens component can be a single lens, a combination of multiple lenses, or an integrally formed lens, etc.

[0025] Optionally, the first prism 32 has a first surface 321, a second surface 322 and a third surface 323, the first surface 321 of the first prism 32 is close to the image source 2, and the third surface 323 of the first prism 32 is close to the lens component. The second prism 34 has a first surface 341 and a second surface 342, the first surface 341 of the second prism 34 is close to the eyebox 7 of the optical system, and the second surface 342 of the second prism 34 is attached to the second surface 322 of the first prism 32. The light emitted by the image source 2 can be incident from the first surface 321 of the first prism 32, after at least one total reflection occurs in the first prism 32, the light is emitted from the third surface 323 of the first prism 32 to the lens component, and after the light reflected by the lens component, the light passes through the first prism 32 again, the second surface 342 of the second prism 34 and the first surface 341 of the second prism 34, and then the light is emitted to the eyebox 7 of the optical system. After the light reaches the eyebox 7 of the optical system, the light can be projected to the eyes of the user wearing the optical system, so that the user can see the display picture.

[0026] In some possible embodiments, the optical system includes a block 4 connected to the support 1, the block 4 is located at the top of the lens component and blocks the part of the third surface 323 of the first prism 32 that exceeds the lens component.

[0027] The light emitted by the image source 2 reaches the top of the third surface 323 of the first prism 32, and a part of the light has an angle that satisfies the total reflection condition, and this part of the light can finally reach the eyebox 7 of the optical system and participate in imaging. Another part of the light will be emitted from the first prism 32 because the angle does not satisfy the total reflection condition, causing image light leakage. Figure 1 The area of the third surface 323 blocked by the block 4 is a light leakage area, and part of the image light will be emitted to the outside from this area.

[0028] Therefore, in the embodiments of the present disclosure, the block 4 is arranged to block a certain area at the top of the third surface 323 of the first prism 32, so as to intercept the light emitted from the first prism 32. Optionally, the area of the top of the third surface 323 of the first prism 32 blocked by the block 4 is not in the visual field range of the wearer, so the user cannot see the block 4 and the viewing experience of the wearer will not be affected.

[0029] In some possible embodiments, as shown in Figure 5 The block 4 is located outside the preset field of view range of the optical system.

[0030] The angle between the edge of the preset field of view and the line connecting the preset eye position is the field of view (FOV) of the optical system. FOV refers to the angle between the edge of the optical imaging portion observable by the human eye at the preset eye position and the line connecting the eye to the frame. In this embodiment, the block 4 is located outside the preset field of view of the optical system. When the user's eyes are at the preset eye position, the area of ​​block 4 is not visible. Therefore, the placement of block 4 does not affect the user's viewing experience. The specific position of block 4 can be determined based on the dimensions of the optical components, the field of view, the eye relief, and the eye box 7 of the optical system. All of the above parameters of an optical system are known values. Based on these parameters, the lowest upper edge of the lens component can be determined, which also determines the lowest placement position of block 4.

[0031] In some possible implementations, the material density of the stop 4 is less than that of the lens component. Since the stop is located on top of the lens component and blocks the portion of the third surface 323 of the first prism 32 that extends beyond the lens component, compared to completely blocking the third surface 323 of the first prism 32 with the lens component, this effectively reduces the height of the lens component and fills the height difference between the lens component and the third surface 323 of the first prism 32. The stop 4, made of a low-density material, blocks the top region of the third surface 323 of the first prism 32, thus reducing the weight of the optical system.

[0032] In some possible implementations, such as Figure 1 As shown, the side of the stop block 4 facing the first prism 32 has a recessed groove 41, and the third surface of the first prism 32 covers the recessed groove 41. The recessed groove 41 is not exposed on the surface of the bracket 1 and does not affect the appearance of the optical system. By creating the recessed groove 41 on the bracket 1, a weight reduction effect is achieved, which helps to reduce the weight of the optical system.

[0033] In some possible embodiments, adjacent optical components in the optical assembly, such as lens components, first prism 32, second prism 34, etc., can be bonded together by adhesive bonding and double-sided adhesive coating of optical films. The entire optical assembly forms a monolithic structure, simplifying the assembly structure between them, and facilitating the assembly of the optical assembly 3 as a whole with other structures in the optical system, such as the bracket 1.

[0034] In some possible embodiments, the image source 2 can be configured to emit light for displaying a picture. The image source 2 can include, but is not limited to, an Organic Light Emitting Diode (OLED) image source 2, a Liquid Crystal image source 2, a Liquid Crystal on Silicon (LCOS) image source 2, a Micro Electro Mechanical System (MEMS) image source 2, a Digital Micromirror Device (DMD), or the like. For example, the image source 2 can be an OLED display screen.

[0035] Figure 4 A structure diagram of a support of an optical system is shown. The support 1 includes a first support part 11 and a second support part 12. The second support part 12 is located on one side of the first support part 11, and the second support part 12 is connected to the first support part 11. The first support part 11 is provided with a first mounting port 111, the second support part 12 is provided with a second mounting port, and the first support part 11 and the second support part 12 are provided with a third mounting port 13. The optical assembly 3 is mounted on the first support part 11 and covers the first mounting port 111. The image source 2 is mounted on the second support part 12 and covers the second mounting port. The stopper 4 is mounted on the third mounting port 13, and the stopper 4 covers one side of the third surface of the first prism 32 close to the second support part 12. Figure 2 and Figure 4 As shown in the structure diagram of the support of the optical system, the optical assembly 3 is mounted on the first support part 11 and covers the first mounting port 111. The image source 2 is mounted on the second support part 12 and covers the second mounting port. The stopper 4 is mounted on the third mounting port 13, and the stopper 4 covers one side of the third surface of the first prism 32 close to the second support part 12.

[0036] Optionally, the first support part 11 and the second support part 12 are an integral structure, and the overall structural strength is high and is not easy to deform. The first support part 11 and the second support part 12 have a certain included angle, so that after the image source 2 and the optical assembly 3 are respectively assembled, the first surface of the first prism 32 of the optical assembly 3 is just directed to the image source 2. The third mounting port 13 is located in a transition region of the first support part 11 and the second support part 12, and the region just corresponds to one side of the upper edge of the third surface 323 of the first prism 32. After the stopper 4 is embedded in the third mounting port 13, the stopper 4 just covers one side of the upper edge of the third surface 323 of the first prism 32.

[0037] In some possible embodiments, as Figure 1As shown, the lens component can include a first lens 31 close to the first prism 32. The first lens 31 can be used to correct the field curvature and provide optical power to achieve a larger field of view. The first lens 31 can be opposite to the third surface 323 of the first prism 32. The side of the first lens 31 away from the third surface 323 of the first prism 32 can be a reflecting surface, and a reflecting film can be provided on the reflecting surface by bonding or the like. The reflecting film can be used to fully reflect or partially reflect the light. If the reflecting film is used to partially reflect the light, the reflecting film can be a semi-reflective film.

[0038] It should be noted that the light emitted by the image source 2 is incident on the first surface 321 of the first prism 32, and after at least one full reflection in the first prism 32, the light is emitted from the third surface 323 of the first prism 32 to the first lens 31. The light reflected by the reflecting film is emitted to the eyebox 7 of the optical system after passing through the first prism 32 again.

[0039] In some possible embodiments, the prism assembly can further include a second lens 33, which can be located on the side of the first lens 31 away from the first prism 32. Optionally, the surface of the second lens 33 close to the first lens 31 can be a reflecting surface. The second lens 33 can be attached to the first lens 31. The second lens 33 can also be a compensating lens for the first lens 31 to compensate for the surface profile of the first lens 31.

[0040] It should be noted that, as shown, Figure 1 The optical system can further include a third lens 6, which is arranged between the image source 2 and the first surface 321 of the first prism 32. The third lens 6 and the first prism 32 have a gap therebetween, and the third lens 6 can be directly or indirectly connected to the image source 2. The light emitted by the image source 2 is incident on the first prism 32 after passing through the third lens 6. The third lens 6 can be an aspherical lens, and the third lens 6 can be used to correct the field curvature, pupil swim, and chromatic aberration to ensure the imaging quality of the optical system. The third lens 6 can also be a positive lens, and the third lens 6 can be a biconvex lens. The third lens 6 can also be a plano-convex lens, and the surface profile of the third lens 6 is relatively regular, which is relatively easy to process.

[0041] It can be seen that, in the optical system provided by the embodiments of the present disclosure, the light emitted by the image source 2 can enter the eyebox 7 of the optical system through the cooperation of the image source 2, the third lens 6, the first prism 32, the second lens 33, the first lens 31, and the second prism 34. In this way, the user can see the display screen provided by the image source 2. Therefore, the optical system can normally display the content to meet the use requirements of the user, for example, to meet the viewing requirements of the user.

[0042] In some possible embodiments, the third installation opening 13 and the first installation opening 111 are in communication, and in the state where the stopper 4 is installed in the third installation opening 13, the stopper 4 covers the thickness end face of the lens component. The thickness end faces of the top sides of the first lens 31 and the second lens 32 are flush, and the stopper 4 can directly cover the thickness end faces of the top sides of the first lens 31 and the second lens 32.

[0043] The third installation opening 13 can be a notch opened at the top edge of the first installation opening 111. After the stopper 4 is inserted into the third installation opening 13, the stopper 4 covers the thickness end face of the lens component. For example, the stopper 4 and the lens component are tightly fitted. The side faces of the stopper 4 and the lens component facing the first prism 32 can be substantially located in the same plane, and the two are in tight contact, and the two can contact, support and limit each other.

[0044] In some possible embodiments, the peripheral side edge of the stopper 4 is adhered to at least one of the support 1 and the optical assembly 3 by a glue. The partial peripheral side end face of the stopper 4 contacts the lens component of the optical assembly 3, and the partial peripheral side end face of the stopper 4 contacts the inner wall of the third installation hole of the support 1. A gap is formed at the peripheral side end face of the stopper 4, and by filling the glue into the gap, the stopper 4 is fixed with the lens component and the support 1, and at the same time, the gap of the peripheral side of the stopper 4 is closed, avoiding the entry of external stray light, dust and the like from the gap.

[0045] As shown in Figure 1 , because of the appearance modeling problem, the second lens 33 has a larger size at the lower end compared with other optical components, that is, the lower edge of the second lens 33 protrudes from the first lens 31 and the first prism 32. This can cause external light to directly enter the optical system through the lower edge of the second lens 33, without entering the human eye through the effective light path, affecting the user experience, referring to the dashed arrow in Figure 1 . It should be noted that the effective light path refers to the external light that at least sequentially passes through the second lens 33, the first lens 31, the first prism 32 and the second prism 34, referring to the solid arrow in Figure 1 . It can be understood that most of the external light that enters the human eye is along the effective light path, and the light passes through the same optical components and thus undergoes the same optical processing. The light that does not enter through the effective light path undergoes different optical processing compared with the light that enters along the effective light path, and therefore, this light is not expected to be seen by the human eye.

[0046] To this end, as shown in Figure 1As shown, in the first support part 11 of the first mounting port 111 away from the second support part 12 side is provided with a shielding table 112, the second lens 33 away from the second support part 12 one end of the first lens 31, the second lens 33 and the first lens 31 between the formation of the step 35, in the state of the optical assembly 3 is installed on the first support part 11, shielding table 112 extends to the step 35. Thus, the external light incident to the lower edge of the second lens 33 will be shielded by the shielding table 112, so that the external light without effective light path can not enter the optical system inside.

[0047] In some possible embodiments, the inner wall of the first mounting port 111 of the first support part 11 is provided with a plurality of grooves 113, and the peripheral side edge of the optical assembly 3 is provided with a plurality of external convex portions, and in the state that the optical assembly 3 is installed on the first support part 11, each external convex portion is embedded in the corresponding groove 113.

[0048] In combination Figures 2 to 4 As shown, each optical component of the optical assembly 3 is first bonded and fixed to form an integral whole, and then the whole optical assembly 3 is installed in the first mounting port 111. By providing a plurality of external convex portions on the peripheral side of the optical assembly 3 and a plurality of grooves 113 on the inner wall of the first mounting port 111, the external convex portions can be embedded in the grooves 113. Through the positioning cooperation of the two, the assembly of the optical assembly 3 and the support 1 is facilitated, and the assembly efficiency is improved. The bottom wall of the groove 113 on the inner wall of the first mounting port 111 can be provided with a boss, and after the external convex portion is embedded in the groove 113, the external convex portion is supported on the boss, and the boss plays a role in stably supporting the optical assembly 3.

[0049] The first mounting port 111 is substantially rectangular, and four grooves 113 can be provided on the first mounting port 111. Two grooves 113 can be provided on each width side of the first mounting port 111, and the two grooves 113 are respectively located at both ends of the corresponding width side. That is, the four grooves 113 can be located at the four corners of the first mounting port 111. Similarly, four external convex portions are provided on the optical assembly 3, and the four external convex portions are respectively embedded in the four grooves 113, so that the optical system can be stably assembled on the support 1.

[0050] In some possible embodiments, the lens component includes a first lens 31 close to the first prism 32 and a second lens 33 away from the first prism 32. In combination Figures 2 to 4 As shown, the external convex portion includes a first external convex portion 324 provided on the edge of the first prism 32 and a second external convex portion 331 provided on the edge of the second lens 33, and each first external convex portion 324 on the edge of the first prism and each second external convex portion 331 on the second lens 33 are one-to-one opposite, and in the state that the optical assembly 3 is installed on the first support part 11, the opposite first external convex portion 324 and the second external convex portion 331 are embedded in the same groove 113.

[0051] As shown in Figure 2 After the optical assembly 3 is installed in the first mounting port 111 of the support 1, a gap 5 is formed between the optical assembly 3 and the support 1, and the gap 5 needs to be filled with glue to seal the gap and fix the optical assembly 3 and the support 1. Because the recess 113 is arranged on the inner wall of the first mounting port 111, the gap 5 is interrupted, resulting in discontinuous glue dispensing. In the embodiment of the present disclosure, the second outer protrusion 331 is arranged on the edge of the second lens 33, which blocks the recess 113, so that the gap 5 formed between the optical assembly 3 and the support 1 is a closed annular gap with a substantially uniform gap width, and continuous and uninterrupted glue dispensing can be conveniently performed around the optical assembly 3, which improves the bonding strength and has an aesthetic effect.

[0052] The embodiment of the present disclosure also provides a head-mounted display device, which comprises a frame structure and the optical system described above, and the optical system is installed on the frame structure. The head-mounted display device can be in the form of glasses, a helmet, etc. Taking smart glasses as an example, the frame structure can be a frame of the smart glasses, and the temples of the smart glasses are connected to the frame. The frame has a crossbeam extending along the width direction of the frame, and the crossbeam has high rigidity. The two optical systems can be connected to the crossbeam. For example, the support 1 of the optical system can be fixed to the crossbeam of the smart glasses by fasteners.

[0053] The above description has been given for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although a plurality of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. An optical system comprising: a bracket; an image source disposed on the bracket; an optical assembly disposed on the bracket, the optical assembly comprising: a lens component; a first prism having a first surface, a second surface and a third surface, the first surface of the first prism being proximate to the image source, the third surface of the first prism being proximate to the lens component; and a second prism having a first surface and a second surface, the first surface of the second prism being proximate to an eyebox of the optical system, the second surface of the second prism being attached to the second surface of the first prism; a stopper connected to the bracket, the stopper being located on a top of the lens component and blocking a portion of the third surface of the first prism beyond the lens component; wherein light emitted from the image source is incident on the first surface of the first prism, undergoes at least one total reflection within the first prism and is emitted from the third surface of the first prism to the lens component, the light reflected by the lens component passes through the first prism again, and is emitted to the eyebox of the optical system after passing through the second surface of the second prism and the first surface of the second prism.

2. The optical system of claim 1, wherein, the bracket comprises a first bracket portion and a second bracket portion, the second bracket portion being located on one side of the first bracket portion, and the second bracket portion and the first bracket portion being connected; a first mounting opening is provided on the first bracket portion; a second mounting opening is provided on the second bracket portion; a third mounting opening is provided between the first bracket portion and the second bracket portion; the optical assembly is mounted on the first bracket portion and covers the first mounting opening; the image source is mounted on the second bracket portion and covers the second mounting opening; the stopper is mounted on the third mounting opening and covers the side of the third surface of the first prism proximate to the second bracket portion.

3. The optical system of claim 2, wherein, the third mounting opening and the first mounting opening are connected; in a state where the stopper is mounted on the third mounting opening, the stopper covers the thickness end surface of the lens component.

4. The optical system of claim 1, wherein, the material density of the stopper is less than the material density of the lens component.

5. The optical system of claim 2, wherein, the lens component comprises a first lens proximate to the first prism and a second lens distal from the first prism; a blocking table is provided on the side of the first mounting opening of the first bracket portion distal from the second bracket portion; an end of the second lens distal from the second bracket portion protrudes out of the first lens, and a step is formed between the second lens and the first lens; in a state where the optical assembly is mounted on the first bracket portion, the blocking table extends to the step.

6. The optical system of claim 2, wherein, an inner wall of the first mounting opening of the first bracket portion is provided with a plurality of grooves; a plurality of convex portions are provided on a peripheral side edge of the optical assembly; in a state where the optical assembly is mounted on the first bracket portion, each of the convex portions is embedded in a corresponding groove.

7. The optical system of claim 6, wherein, the lens component comprises a first lens proximate to the first prism and a second lens distal from the first prism; The outer protrusions include first outer protrusions provided on the first prism edge and second outer protrusions provided on the second lens edge; Each first outer protrusion on the first prism edge and each second outer protrusion on the second lens edge are located one-to-one in opposition; In a state where the optical assembly is mounted on the first support portion, the opposed first outer protrusion and second outer protrusion are embedded in the same groove.

8. The optical system of any of claims 1-7, wherein, A recessed groove is provided on a side of the stopper facing the first prism; A third surface of the first prism covers the recessed groove.

9. The optical system of any of claims 1-7, wherein, The stopper is located outside a preset field of view range of the optical system.

10. A head-mounted display device comprising: a frame structure; the optical system according to any one of claims 1-9, the optical system being mounted on the frame structure.

Images