WO2020244210A1 - Optical system and virtual reality device having same - Google Patents

Abstract

Disclosed are an optical system and a virtual reality device having same. The optical system comprises, in order along a light transmission direction, a display unit (10), a reflective polarizer (20) and a lens set (40). The optical system further comprises phase retarders (30), wherein the phase retarders (30) comprise a first phase retarder (31), and the first phase retarder (31) is arranged on a side, close to the display unit (10), of the reflective polarizer (20). A first surface or a second surface of the lens set (40) is provided with an optical splitter. Incident light emitted by the display unit (10) passes through the first phase retarder (31), then is reflected by the reflective polarizer (20), passes through the first phase retarder (31) again, then is emitted to the lens set (40), is reflected by the optical splitter of the lens set (40), then passes through the first phase retarder (31), and is emitted from the optical system from the reflective polarizer (20). In this way, the problem in the prior art whereby light passing through an optical system of a virtual reality device is prone to ghosting such that the use of the virtual reality device by a user is affected is solved.

Description

Optical system and virtual reality equipment with same Technical field

The invention relates to the field of optical imaging technology, in particular to an optical system and a virtual reality device having the same.

Background technique

Virtual reality technology is a technology that uses a computer to generate a simulated environment to immerse users in the environment. Among them, the optical system of virtual reality equipment is usually realized by a single lens or a combination of multiple lenses. The incident light passes through the optical system. When the lens surface produces reflected light, the reflected light passes through the optical system and enters the human eye to form a ghost image, which affects the user's use of the virtual reality device.

Summary of the invention

The present invention provides an optical system and a virtual reality device having the same, and aims to solve the problem that light passing through the optical system of the virtual reality device in the prior art is likely to produce ghost images and affect the use of the virtual reality device by users.

In order to achieve the above objective, the present invention proposes an optical system which sequentially includes a display unit, a reflective polarizer and a mirror group along the light transmission direction,

The vertical line of the center of the display unit intersects the extension line of the optical axis of the lens group;

The lens group includes a first surface close to the reflective polarizer and a second surface away from the reflective polarizer;

The optical system further includes a phase retarder, the phase retarder includes a first phase retarder, and the first phase retarder is provided on a side of the reflective polarizer close to the display unit;

The first surface or the second surface is provided with a beam splitter;

The incident light emitted by the display unit becomes first linearly polarized light after passing through the first phase retarder, and the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer. The first linearly polarized light is reflected by the reflective polarizer and returns to the first phase retarder, and becomes the first circularly polarized light or the first elliptically polarized light with the same rotation as the incident light, and the first circularly polarized light The light or the first elliptically polarized light is directed to the lens group, and is transmitted and reflected by the beam splitter. The transmitted light exits the lens group from the second surface and is transmitted to the human eye; the reflected light becomes the second Circularly polarized light or second elliptically polarized light, the rotation of the second circularly polarized light is opposite to the rotation of the first circularly polarized light, and the rotation of the second elliptically polarized light is the same as that of the first elliptically polarized light The rotation of the light is opposite; the second circularly polarized light or the second elliptically polarized light becomes second linearly polarized light after passing through the first phase retarder again, and the second linearly polarized light changes from the reflective polarized light The sheet transmits and exits the optical system.

Optionally, the angle between the reflection axis of the reflective polarizer and the retardation axis of the first phase retarder is 45 degrees.

Optionally, the first phase retarder is a quarter wave plate.

Optionally, the phase retarder includes a first phase retarder and a second phase retarder; the first phase retarder is arranged on a side surface of the reflective polarizer close to the display unit and close to all One end of the display unit is provided, and the second phase retarder is provided on a side surface of the reflective polarizer close to the display unit and close to one end of the mirror group;

The incident light emitted by the display unit becomes first linearly polarized light after passing through the first phase retarder, and the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer. The first linearly polarized light is reflected by the reflective polarizer and returns to the first phase retarder, and becomes the first circularly polarized light or the first elliptically polarized light with the same rotation as the incident light, and the first circularly polarized light The light or the first elliptically polarized light is directed to the lens group, and is transmitted and reflected by the beam splitter. The transmitted light exits the lens group from the second surface and is transmitted to the human eye; the reflected light becomes the second Circularly polarized light or second elliptically polarized light, the rotation of the second circularly polarized light is opposite to the rotation of the first circularly polarized light, and the rotation of the second elliptically polarized light is the same as that of the first elliptically polarized light The rotation of the light is opposite; the second circularly polarized light or the second elliptically polarized light becomes second linearly polarized light after passing through the second phase retarder, and the second linearly polarized light changes from the reflective polarizer The optical system is transmitted and emitted.

Optionally, the angles between the reflection axis of the reflective polarizer and the retardation axis of the first phase retarder and the retardation axis of the second phase retarder are both 45 degrees.

Optionally, both the first phase retarder and the second phase retarder are quarter-wave plates.

Optionally, the angle between the reflective polarizer and the display unit is 45 degrees; the angle between the center perpendicular of the reflective polarizer and the optical axis of the mirror group is 45 degrees; the display unit It is perpendicular to the mirror group.

Optionally, the optical system further includes a third phase retarder, and the third phase retarder is provided between the display unit and the first phase retarder.

Optionally, the optical system further includes an extinction element, and the extinction element is arranged on a side of the reflective polarizer away from the lens group.

In order to achieve the foregoing objective, this application proposes a virtual reality device, which is characterized in that the virtual reality device includes the optical system as described in any of the foregoing embodiments.

In the technical solution proposed in the present application, the optical system includes a display unit, a reflective polarizer, and a mirror group in sequence along the light transmission direction, and the mirror group includes a first surface close to the reflective polarizer and a mirror group away from the reflective polarizer. The second surface of the reflective polarizer; the optical system further includes a phase retarder, the phase retarder includes a first phase retarder, and the first phase retarder is arranged on the reflective polarizer close to the display unit The incident light emitted by the display unit passes through the first phase retarder and is reflected in the reflective polarizer, passes through the first phase retarder again, and becomes first circularly polarized light and Directed toward the mirror group, the first surface or the second surface is provided with a beam splitter, and the first circularly polarized light is reflected by the beam splitter as a second circularly polarized light, and the second circularly polarized light The rotation of the light is opposite to the rotation of the first circularly polarized light, the second circularly polarized light passes through the first phase retarder to become the second linearly polarized light, and the polarization direction of the second linearly polarized light The direction of the transmission axis of the reflective polarizer is the same, so the second linearly polarized light passes through the reflective polarizer. Therefore, it is avoided that the reflected light enters the human eye again to form a ghost, thereby solving the problem that the light passing through the optical system of the virtual reality device in the prior art is prone to ghosting and affecting the use of the virtual reality device by the user.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, without creative work, other drawings can be obtained based on the structures shown in these drawings.

Figure 1 is a schematic diagram of the optical path of an embodiment of the optical system of the present invention;

2 is a schematic diagram of the optical path of another embodiment of the optical system of the present invention;

Fig. 3 is a schematic diagram of the optical path of another embodiment of the optical system of the present invention.

Description with icon number:

Label name Label name 10 Display unit 33 Third phase retarder 20 Reflective polarizer 40 Mirror group 30 Phase retarder 41 First surface 31 First phase retarder 42 Second surface 32 Second phase retarder 50 Matting element

The realization of the objectives, functional characteristics and advantages of the present invention will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that all directional indicators (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relationship between components in a particular posture (as shown in the accompanying drawings). If the relative position relationship, movement situation, etc. change, the directional indication will change accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

In the present invention, unless otherwise clearly specified and limited, the terms "connected", "fixed", etc. should be understood in a broad sense, for example, "fixed" can be a fixed connection, a detachable connection, or a whole; It can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication between two components or the interaction relationship between two components, unless specifically defined otherwise. For those of ordinary skill in the art, the specific meaning of the above-mentioned terms in the present invention can be understood according to specific circumstances.

In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but they must be based on what can be achieved by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that this combination of technical solutions It does not exist and does not fall within the scope of protection required by the present invention.

The invention provides an optical system and a virtual reality device with the optical system.

1 to 3, the optical system includes a display unit 10, a reflective polarizer 20, and a mirror group 40 in sequence along the light transmission direction.

The center perpendicular of the display unit 10 intersects the extension line of the optical axis of the lens group 40;

The lens group 40 includes a first surface 41 close to the reflective polarizer 20 and a second surface 42 away from the reflective polarizer 20;

The optical system further includes a phase retarder 30, and the phase retarder 30 is provided on a side of the reflective polarizer 20 close to the display unit 10;

The first surface 41 or the second surface 42 is provided with a beam splitter;

The incident light emitted by the display unit 10 becomes the first linearly polarized light after passing through the phase retarder 30, and the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer 20, so The first linearly polarized light is reflected by the reflective polarizer 20 and then returns to the phase retarder 30 to become first circularly polarized light or first elliptically polarized light with the same rotation as the incident light. The polarized light or the first elliptically polarized light is directed to the mirror group 40, and is transmitted and reflected by the beam splitter. The transmitted light exits the mirror group 40 from the second surface 42 and is transmitted to the human eye; reflected light Becomes a second circularly polarized light or a second elliptically polarized light, the rotation of the second circularly polarized light is opposite to that of the first circularly polarized light, and the rotation of the second elliptically polarized light is the same as that of the The rotation of the first elliptically polarized light is opposite; the second circularly polarized light or the second elliptically polarized light becomes second linearly polarized light after passing through the phase retarder 30 again, and the second linearly polarized light changes from the The reflective polarizer 20 transmits and exits the optical system.

In the technical solution proposed in the present application, the optical system includes a display unit 10, a reflective polarizer 20, and a mirror group 40 in sequence along the light transmission direction. The mirror group 40 includes a first surface close to the reflective polarizer 20. 41 and the second surface 42 away from the reflective polarizer 20; the optical system further includes a phase retarder 30, the phase retarder 30 is provided on the reflective polarizer 20 near the display unit 10 Side; the incident light emitted by the display unit 10 passes through the phase retarder 30 and is reflected in the reflective polarizer 20, passes through the phase retarder 30 again, and becomes the first circularly polarized light and is directed toward In the mirror group 40, the first surface 41 or the second surface 42 is provided with a beam splitter, and the first circularly polarized light is reflected by the beam splitter as a second circularly polarized light. The rotation of the polarized light is opposite to the rotation of the first circularly polarized light. The second circularly polarized light passes through the phase retarder 30 and becomes the second linearly polarized light. The polarization direction of the second linearly polarized light is The direction of the transmission axis of the reflective polarizer 20 is the same, so the second linearly polarized light passes through the reflective polarizer 20. Therefore, it is avoided that the reflected light enters the human eye again to form a ghost, thereby solving the problem that the light passing through the optical system of the virtual reality device in the prior art is prone to ghosting and affecting the use of the virtual reality device by the user.

In a preferred embodiment, the spectroscope is a spectroscopic film, specifically, the spectroscopic film is a semi-reflective semi-transparent film, and the ratio of transmittance to reflectance of the semi-reflective semi-transparent film is 1:1, which is understandable Yes, the light splitting ratio of the beam splitter is not limited to this. In other embodiments, the ratio of the transmittance to the reflectance of the beam splitter may also be 4:6 or 3:7. It is understandable that the beam splitter may also be a beam splitting element, and the beam splitting element may be a beam splitter or other optical elements capable of splitting light.

1, in some optional embodiments, the phase retarder 30 includes a first phase retarder 31. Specifically, the first phase retarder 31 covers the reflective polarizer 20 close to the One side surface of the display unit 10 is provided, and the first surface 41 is provided with a beam splitter. The incident light emitted by the display unit 10 becomes first linearly polarized light after passing through the first phase retarder 31, and the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer 20 , The first linearly polarized light is reflected by the reflective polarizer 20 and then returns to the first phase retarder 31 to become first circularly polarized light or first elliptically polarized light with the same rotation as the incident light, so The first circularly polarized light or the first elliptically polarized light is directed to the mirror group 40, and is transmitted and reflected by the beam splitter. The transmitted light exits the mirror group 40 from the second surface 42 and is transmitted to the person. Eye; the reflected light becomes a second circularly polarized light or a second elliptically polarized light, the rotation of the second circularly polarized light is opposite to the rotation of the first circularly polarized light, and the rotation of the second elliptically polarized light Is opposite to that of the first elliptically polarized light; the second circularly polarized light or the second elliptically polarized light becomes second linearly polarized light after passing through the first phase retarder 31 again, due to the The polarization direction of the second linearly polarized light is the same as the transmission axis direction of the reflective polarizer 20, so the second linearly polarized light is transmitted through the reflective polarizer 20 and exits the optical system.

In a preferred embodiment, the angle between the reflection axis of the reflective polarizer 20 and the first phase retarder 31 is 45 degrees. Specifically, when the angle between the reflection axis of the reflective polarizer 20 and the first phase retarder 31 is 45 degrees, the first linearly polarized light reflected by the reflective polarizer 20 is After passing through the first phase retarder 31, the polarization state of the first linearly polarized light changes from linearly polarized light to circularly polarized light. When the reflection axis of the reflective polarizer 20 and the first phase retarder When the retardation axis of 31 is not 45 degrees, the polarization state of the first linearly polarized light changes from linearly polarized light to elliptically polarized light, and the elliptically polarized light returns to the reflective polarizer after being reflected by the beam splitter It becomes linearly polarized light again at 20 o'clock. Since the reflection axis of the reflective polarizer 20 and the retardation axis of the first phase retarder 31 are not 45 degrees, the linearly polarized light converted from elliptically polarized light cannot be completely transmitted. The reflective polarizer 20, therefore, there is a part of the light reflected by the reflective polarizer 20, and eventually it is easy to return to the mirror group 40 and form a ghost image, which affects the user's perception.

Preferably, the first phase retarder 31 is a first quarter-wave plate. In a specific embodiment, the center wavelength of the first quarter-wave plate is equal to the wavelength of the incident light, and the first The angle between the fast or slow axis of the quarter wave plate and the polarization direction of the incident light is 45 degrees. Specifically, the incident light is right-handed circularly polarized light, and the incident light passes through the first 1 After the /4 wave plate becomes the first linearly polarized light, the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer 20, so the first linearly polarized light is Reflected by the reflective polarizer 20, the first linearly polarized light passes through the first quarter-wave plate again and then becomes first circularly polarized light. The first circularly polarized light is right-handed circularly polarized light. After being reflected by the beam splitter, the first circularly polarized light becomes the second circularly polarized light, the second circularly polarized light is left-handed circularly polarized light, and the second circularly polarized light passes through the first 1/ After the 4-wave plate becomes the second linearly polarized light, the polarization direction of the second linearly polarized light and the polarization direction of the first linearly polarized light are perpendicular to each other and are the same as the transmission axis direction of the reflective polarizer 20 Therefore, the second linearly polarized light passes through the reflective polarizer 20 and does not transmit along the original optical path, thereby avoiding the problem of ghost images caused by the reflected light in the optical system.

Please refer to FIG. 2, in some alternative embodiments, the phase retarder 30 includes a first phase retarder 31 and a second phase retarder 32. Specifically, the first phase retarder 31 is provided on a surface of the reflective polarizer 20 close to the display unit 10 and is provided close to one end of the display unit 10. The second phase retarder 32 The reflective polarizer 20 is arranged on a side surface of the reflective polarizer 20 close to the display unit 10 and close to one end of the mirror group 40, and the second surface 42 is provided with a beam splitter.

The incident light emitted by the display unit 10 passes through the first phase retarder 31 and is reflected by the reflective polarizer 20, passes through the first phase retarder 31 again, and is directed to the mirror group 40, and is After being reflected by the beam splitter of the mirror group 40, the optical system is emitted from the reflective polarizer 20 through the second phase retarder 32.

In a preferred embodiment, the angles between the reflection axis of the reflective polarizer 20 and the first phase retarder 31 and the second phase retarder 32 are both 45 degrees. Specifically, the first phase retarder 31 and the second phase retarder 32 are both parallel to the reflective polarizer 20, when the reflection axis of the reflective polarizer 20 and the first phase retarder When the angle between 31 and the second phase retarder 32 is 45 degrees, the first linearly polarized light reflected by the reflective polarizer 20 passes through the first phase retarder 31, the The polarization state of the first linearly polarized light is changed from linearly polarized light to circularly polarized light. When the reflection axis of the reflective polarizer 20 and the retardation axis of the first phase retarder 31 are not 45 degrees, the first The polarization state of a linearly polarized light changes from linearly polarized light to elliptically polarized light. After being reflected by the beam splitter, the elliptically polarized light passes through the second phase retarder 32 and returns to the reflective polarizer 20. It is linearly polarized light. Since the reflection axis of the reflective polarizer 20 and the retardation axis of the first phase retarder 31 are not 45 degrees, the linearly polarized light converted from elliptically polarized light cannot completely pass through the reflective polarizer. The polarizer 20, therefore, there is a part of the light reflected by the reflective polarizer 20, and it is easy to eventually return to the lens group 40 and form ghost images, which affects the user's perception.

In a preferred embodiment, the first phase retarder 31 and the second phase retarder 32 are both quarter-wave plates. Specifically, the center wavelength of the first quarter wave plate is equal to the wavelength of the incident light, the center wavelength of the second quarter wave plate is equal to the wavelength of the incident light, and the first 1 The angle between the fast or slow axis of the /4 wave plate and the polarization direction of the incident light is 45 degrees, and the fast or slow axis of the second quarter wave plate and the polarization direction of the incident light are sandwiched between The angle is 45 degrees, and the first quarter wave plate and the second quarter wave plate are used to convert linearly polarized light into circularly polarized light.

In some optional embodiments, the angle between the reflective polarizer 20 and the display unit 10 is 45 degrees; the center perpendicular of the reflective polarizer 20 and the optical axis of the mirror assembly 40 The angle is 45 degrees; the display unit 10 and the lens group 40 are perpendicular to each other. In a specific embodiment, the incident angle and the reflection angle of the incident light emitted by the display unit 10 on the reflective polarizer 20 are both 45 degrees, and the light transmission direction of the first circularly polarized light is the same as that of the mirror. The optical axis directions of the groups 40 are the same, so it is ensured that when the first circularly polarized light is transmitted to the mirror group 40, it can be returned to the reflective polarizer 20 in the opposite direction by the beam splitter. When the angle between the reflective polarizer 20 and the display unit 10 is not 45, it is necessary to precisely adjust the relative positions of the display unit 10, the reflective polarizer 20, and the mirror group 40, thereby It is ensured that the incident light emitted by the display unit 10 can be transmitted to the mirror group 40 after being reflected by the reflective polarizer 20, which increases the difficulty of assembling the optical system.

1 to 3, in some alternative embodiments, the optical system further includes a delustering element 50, the delustering element 50 is provided on the side of the reflective polarizer 20 away from the lens group 40 Specifically, in order to prevent the second linearly polarized light from being reflected again through the reflective polarizer 20 after passing through the reflective polarizer 20, the reflective polarizer 20 is far away from the mirror One side of the group 40 is provided with the extinction element 50, and the extinction element 50 is used to absorb or scatter the second linearly polarized light passing through the reflective polarizer 20. In a preferred embodiment, the extinction element 50 is Black curtain. It is understandable that the matting element 50 is not limited to this. In other embodiments, the matting element 50 may be an absorbing film or anti-glare glass or a black coating.

3, in some optional implementation manners, the phase retarder 30 further includes a third phase retarder 33, the third phase retarder 33 is provided in the display unit 10 and the first phase Between the retarder 31. Specifically, when the incident light emitted by the display unit 10 is linearly polarized light, in order to ensure that the incident light can eliminate or reduce the influence of ghosts after passing through the optical system, the display unit 10 The third phase retarder 33 is arranged between the first phase retarder 31, and the third phase retarder 33 is used to convert the incident light emitted by the display unit 10 from linearly polarized light to circular light. Polarized light or elliptically polarized light, thereby ensuring the anti-ghost effect of the optical system. In a preferred embodiment, the angle between the retardation axis of the third phase retarder 33 and the polarization direction of the incident light is 45 degrees, so that the incident light is converted into circularly polarized light.

In some optional implementation manners, the third phase retarder is a third quarter wave plate. In specific implementations, the center wavelength of the third quarter wave plate is equal to the wavelength of the incident light. The angle between the fast axis or the slow axis of the third quarter wave plate and the polarization direction of the incident light is 45 degrees. When the incident light is linearly polarized light, the incident light passes through the first After three quarter wave plates, the incident light changes from linearly polarized light to circularly polarized light.

In some optional embodiments, the optical system further includes a beam splitter (not shown), which is arranged parallel to the reflective polarizer 20. Specifically, the beam splitter and the reflective polarizer 20 The polarizer 20 is connected, and the beam splitter is used to support the reflective polarizer 20 and position the reflective polarizer 20.

The present invention also provides a virtual reality device. The virtual reality device includes the optical system as described in any of the above embodiments. For the specific structure of the optical system, refer to the above embodiments. Because the optical system adopts all the above embodiments. All the technical solutions, therefore, at least have all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, and will not be repeated here.

The above descriptions are only the preferred embodiments of the present invention, and do not limit the scope of the present invention. Under the inventive concept of the present invention, equivalent structural transformations made by using the contents of the description and drawings of the present invention, or direct/indirect use Other related technical fields are included in the scope of patent protection of the present invention.

Claims (10)

An optical system, characterized in that the optical system sequentially includes a display unit, a reflective polarizer and a mirror group along the light transmission direction, The vertical line of the center of the display unit intersects the extension line of the optical axis of the lens group; The lens group includes a first surface close to the reflective polarizer and a second surface away from the reflective polarizer; The optical system further includes a phase retarder, the phase retarder includes a first phase retarder, and the first phase retarder is provided on a side of the reflective polarizer close to the display unit; The first surface or the second surface is provided with a beam splitter; The incident light emitted by the display unit becomes first linearly polarized light after passing through the first phase retarder, and the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer. The first linearly polarized light is reflected by the reflective polarizer and returns to the first phase retarder, and becomes the first circularly polarized light or the first elliptically polarized light with the same rotation as the incident light, and the first circularly polarized light The light or the first elliptically polarized light is directed to the lens group, and is transmitted and reflected by the beam splitter. The transmitted light exits the lens group from the second surface and is transmitted to the human eye; the reflected light becomes the second Circularly polarized light or second elliptically polarized light, the rotation of the second circularly polarized light is opposite to the rotation of the first circularly polarized light, and the rotation of the second elliptically polarized light is the same as that of the first elliptically polarized light The rotation of the light is opposite; the second circularly polarized light or the second elliptically polarized light becomes second linearly polarized light after passing through the first phase retarder again, and the second linearly polarized light changes from the reflective polarized light The sheet transmits and exits the optical system. 3. The optical system of claim 1, wherein the angle between the reflection axis of the reflective polarizer and the retardation axis of the first phase retarder is 45 degrees. 5. The optical system of claim 1, wherein the first phase retarder is a quarter wave plate. 3. The optical system of claim 1, wherein the phase retarder comprises a first phase retarder and a second phase retarder; the first phase retarder is arranged on the reflective polarizer near the One side surface of the display unit is disposed close to one end of the display unit, and the second phase retarder is disposed on a side surface of the reflective polarizer close to the display unit and close to one end of the mirror group Set up The incident light emitted by the display unit becomes first linearly polarized light after passing through the first phase retarder, and the polarization direction of the first linearly polarized light is the same as the reflection axis direction of the reflective polarizer. The first linearly polarized light is reflected by the reflective polarizer and returns to the first phase retarder, and becomes the first circularly polarized light or the first elliptically polarized light with the same rotation as the incident light, and the first circularly polarized light The light or the first elliptically polarized light is directed to the lens group, and is transmitted and reflected by the beam splitter. The transmitted light exits the lens group from the second surface and is transmitted to the human eye; the reflected light becomes the second Circularly polarized light or second elliptically polarized light, the rotation of the second circularly polarized light is opposite to the rotation of the first circularly polarized light, and the rotation of the second elliptically polarized light is the same as that of the first elliptically polarized light The rotation of the light is opposite; the second circularly polarized light or the second elliptically polarized light becomes second linearly polarized light after passing through the second phase retarder, and the second linearly polarized light changes from the reflective polarizer The optical system is transmitted and emitted. The optical system of claim 4, wherein the angles between the reflection axis of the reflective polarizer and the retardation axis of the first phase retarder and the retardation axis of the second phase retarder are both 45 degree. 8. The optical system of claim 4, wherein the first phase retarder and the second phase retarder are both quarter-wave plates. The optical system of claim 1, wherein the angle between the reflective polarizer and the display unit is 45 degrees; the center perpendicular of the reflective polarizer and the optical axis of the mirror group The included angle is 45 degrees; the display unit and the mirror group are perpendicular to each other. 8. The optical system of claim 1, wherein the optical system further comprises a third phase retarder, and the third phase retarder is provided between the display unit and the first phase retarder. 8. The optical system according to any one of claims 1-8, wherein the optical system further comprises a delustering element, and the delustering element is arranged on a side of the reflective polarizer away from the lens group. A virtual reality device, characterized in that, the virtual reality device comprises the optical system according to any one of claims 1-9.

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