CN217846782U

CN217846782U - Optical module and head-mounted display equipment

Info

Publication number: CN217846782U
Application number: CN202221344144.5U
Authority: CN
Inventors: 史柴源
Original assignee: Goertek Optical Technology Co Ltd
Current assignee: Goertek Optical Technology Co Ltd
Priority date: 2022-05-30
Filing date: 2022-05-30
Publication date: 2022-11-18
Anticipated expiration: 2032-05-30

Abstract

The embodiment of the utility model provides an optical module and a head-mounted display device; the optical module comprises a light splitting element, a first phase retarder, a polarization reflecting element and a polarization element, wherein the polarization reflecting element is positioned between the first phase retarder and the polarization element; the optical module further comprises a first lens and a second lens; wherein the first lens is located between the beam splitting element and the first phase retarder, the second lens is located between the polarization reflection element and the polarization element, and the first phase retarder and the polarization reflection element are located between the first lens and the second lens. The utility model discloses the scheme can carry out effectual control to stray light.

Description

Optical module and head-mounted display equipment

Technical Field

The embodiment of the utility model provides a near-eye display imaging technology field is related to, more specifically, the embodiment of the utility model relates to an optical module and head-mounted display equipment.

Background

In recent years, augmented Reality (AR) technology, virtual Reality (VR) technology, and the like have been applied to, for example, smart wearable devices and have been rapidly developed. The core components of the augmented reality technology and the virtual reality technology are optical modules. The quality of optical module display effect will directly decide the quality of intelligent wearing equipment.

Currently, optical films used in folded optics (pancake) are all composite films. Namely, films with different functions are overlapped and attached together to form a composite film layer. Thus, although the different film layers are on the same optical axis, the angles between the different film layers are all in accordance with the alignment angle at the time of bonding. In fact, there is a certain alignment error during the attachment, and the angle error may cause the light not to have theoretical phase retardation, so that stray light is introduced, and the imaging effect is finally affected.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an optical module and wear display device's new technical scheme.

In a first aspect, the present invention provides an optical module, which includes a beam splitting element, a first phase retarder, a polarization reflective element and a polarization element, wherein the polarization reflective element is located between the first phase retarder and the polarization element;

the optical module further comprises a first lens and a second lens;

wherein the first lens is located between the light splitting element and the first phase retarder, the second lens is located between the polarization reflecting element and the polarizing element, and the first phase retarder and the polarization reflecting element are located between the first lens and the second lens.

Optionally, the optical module further includes a display, and the light splitting element is located on a light emitting side of the display;

the ratio of the stray light energy of the optical module to the light energy emitted by the display is less than 1%.

Optionally, the optical module further includes a third lens, the second lens is located between the first lens and the third lens, and the third lens is configured to transmit the light exiting through the second lens.

Optionally, the first phase retarder is attached to the first lens, the polarization reflection element is attached to the second lens, and the polarization element is attached to the third lens.

Optionally, the first lens comprises a first surface and a second surface;

the second lens comprises a third surface and a fourth surface;

the third lens comprises a fifth surface and a sixth surface;

wherein the second surface is disposed adjacent to the third surface, and the fourth surface is disposed adjacent to the fifth surface;

the first phase retarder is attached to the second surface, the polarization reflection element is attached to the third surface, and the polarization element is attached to the fifth surface.

Optionally, the light splitting element is disposed on one side of the first surface; alternatively, the first and second electrodes may be,

the light splitting element is attached to the first surface.

Optionally, a center thickness T of the first lens ₁ Is 3mm < T ₁ < 8mm, center thickness T of said second lens ₂ T is more than 2.5mm ₂ ＜6mm。

Optionally, the optical power of the first lens

Is composed of

The focal power of the second lens

Is composed of

Optionally, a center thickness T of the third lens ₃ Is T of 2.5mm < T ₃ ＜6mm。

Optionally, the display is configured to be able to emit circularly polarized light or linearly polarized light;

when the light emitted from the light-emitting surface of the display is linearly polarized light, a second phase delay is arranged between the light-emitting surface of the display and the first lens, and the second phase delay is used for converting the linearly polarized light into circularly polarized light.

Optionally, the light splitting element has a reflectivity of 47% to 53%.

In a second aspect, the present invention provides a head-mounted display device, which includes:

a housing; and

an optical module as described above.

According to the utility model discloses an embodiment provides a folding light path scheme, lays polarization component, polarization reflecting element and phase delay ware independence respectively between a plurality of lenses in the light path structure, like this, through the angle between real-time regulation polarization component, polarization reflecting element, phase delay ware, can acquire the minimum condition of stray light to can carry out effective control to the stray light of optics module.

Other features of the present description and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the specification and together with the description, serve to explain the principles of the specification.

Fig. 1 is a schematic structural diagram of an optical module according to an embodiment of the present invention;

fig. 2 is a schematic partial structural view of an optical module according to an embodiment of the present invention;

fig. 3 is a second partial schematic structural diagram of an optical module according to an embodiment of the present invention;

fig. 4 is a second schematic structural diagram of an optical module according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a spot array of the optical module shown in FIG. 1;

FIG. 6 is a graph of MTF for the optical module shown in FIG. 1;

FIG. 7 is a field curvature distortion diagram of the optical module shown in FIG. 1;

FIG. 8 is a vertical axis chromatic aberration diagram of the optical module shown in FIG. 1;

fig. 9 is a third schematic structural diagram of an optical module according to an embodiment of the present invention.

Description of the reference numerals:

10. a first lens; 11. a first surface; 12. a second surface; 20. a second lens; 21. a third surface; 22. a fourth surface; 30. a third lens; 31. a fifth surface; 32. a sixth surface; 40. A light-splitting element; 50. a first phase retarder; 60. a polarizing reflective element; 70. a polarizing element; 80. A display; 81. protecting glass; 91. a first anti-reflection film; 92. a second anti-reflection film; 01. the human eye; 02. a camera.

Detailed Description

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

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be considered a part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

The optical module and the head-mounted display device provided by the embodiment of the invention are described in detail below with reference to fig. 1 to 9.

According to the utility model discloses an aspect provides an optical module, optical module is a folding light path optical structure design, and it can be fit for being applied to Head-mounted display device (Head mounted display, HMD). For example, VR headset, if can include VR glasses or VR helmet, etc., the embodiments of the present invention do not specifically limit this.

An embodiment of the present invention provides an optical module, as shown in fig. 1 to fig. 4 and fig. 9, the optical module includes a light splitting element 40, a first phase retarder 50, a polarization reflective element 60 and a polarization element 70, wherein the polarization reflective element 60 is located between the first phase retarder 50 and the polarization element 70; the optical module further comprises a lens group, which may include a first lens 10 and a second lens 20;

the first lens 10 is located between the beam splitter 40 and the first phase retarder 50, the second lens 20 is located between the polarization reflection element 60 and the polarization element 70, and the first phase retarder 50 and the polarization reflection element 60 are located between the first lens 10 and the second lens 20.

The embodiment of the utility model provides an in the embodiment, a folding light path scheme is provided, the design lays polarization component 70 in whole light path structure independently between a plurality of optical lens (lens) polarization reflecting element 60 and first phase delay ware 50, because polarization component 70, these blooming (or being called optical element) of polarization reflecting element 60 and first phase delay ware 50 are independent setting, thus, can be through adjusting polarization component 70 in real time, polarization reflecting element 60, the angle between first phase delay ware 50, can acquire the minimum condition of stray light, thereby can carry out effective control to optical module's stray light, finally can improve the quality of formation of image.

It should be noted that, in the embodiment of the present invention, each lens in the first phase retarder 50, the polarization reflection element 60, the polarization element 70 and the lens set is located on the same optical axis, and the angle that can be adjusted between the first phase retarder 50, the polarization reflection element 60 and the polarization element 70 means that these optical elements can rotate along the optical axis, so that the angles can be adjusted to suitable angles, and the three can be aligned, so that the three can achieve accurate alignment and matching, and the minimum stray light can be achieved.

In fact, in the related art, a polarizing film, a polarizing reflective film and a quarter-wave plate applied to a folding optical system (pancake) are generally stacked in a predetermined order to form a composite film layer, and then disposed in an optical path structure. In this case, however, the angles between the different film layers are all in accordance with the alignment angle at the time of bonding. Because alignment errors exist during attaching, the light cannot generate theoretical phase delay due to the angle errors, stray light is introduced, and the imaging effect is influenced finally.

The embodiment of the utility model provides a defect problem among the prior art has been overcome to the scheme, because for the mutually independent design between each blooming, can be through adjusting the angle between different blooming in real time to this acquires the minimum condition of stray light, just so can carry out effective control to the stray light of optical module, improves optical module's optical property, helps making the user obtain good visual experience.

The embodiment of the present invention provides an optical module, which includes a plurality of optical lenses, and further includes the above-mentioned light splitting element 40, the first phase retarder 50, the polarization reflecting element 60, and the polarization element 70.

The first phase retarder 50 may be used to change the polarization state of light in the folded optical path structure. For example, it is possible to convert linearly polarized light into circularly polarized light, or to convert circularly polarized light into linearly polarized light.

The polarization reflection element 60 can be used for transmitting P-polarized light and reflecting S-polarized light; alternatively, the polarizing reflective element 60 may be used to reflect P-polarized light through S-polarized light. The first phase retarder 50, in cooperation with the polarization reflective element 60, may be used to resolve and transmit light.

The polarizing element 70 transmits P-polarized light, and stray light can be reduced.

The beam splitter 40 is, for example, a transflective film, the first phase retarder 50 is a quarter-wave plate, the polarization reflector 60 is a polarization reflector, and the polarizer 70 is a polarizing film.

The embodiment of the utility model provides an optical module, it is a folding light path optical structure design, as shown in FIG. 1, FIG. 4 and FIG. 9, each optical lens piece and optical element in the optical module can arrange and be located same optical axis according to the mode of setting for. The size of the whole light path structure is small, and the whole light path structure does not occupy large space.

In some examples of the present invention, as shown in fig. 1, 4 and 9, the optical module further includes a display 80, and the light splitting element 40 is located on a side of the display 80 where light exits; the ratio of the stray light energy of the optical module to the light energy emitted by the display 80 is < 1%.

That is, the optical module provided by the present invention, in addition to the lens set and the plurality of optical films (optical elements), can further include a display 80, and the display 80 can emit circularly polarized light, for example.

The embodiment of the utility model provides an optical module can be with stray light ratio control < 1%.

The stray light ratio refers to a ratio of stray light energy of the optical module to light energy emitted by the display 80. The stray light ratio of the optical module is controlled within the range, so that the optical module has the characteristics of less stray light and better imaging quality.

In some examples of the present invention, as shown in fig. 1, 4 and 9, the optical module further includes a third lens 30, the second lens 20 is located between the first lens 10 and the third lens 30, and the third lens 30 is configured to transmit light emitted through the second lens 20.

That is, for example, three optical lenses may be included in the lens group of the optical module. Specifically, the lens group may include a first lens 10, a second lens 20, and a third lens 30. The three optical lenses can be used to separate the beam splitter 40, the first retarder 50, the polarization reflection element 60, and the polarization element 70 from each other and to arrange them independently, so that they can be adjusted independently.

In some examples of the present invention, the first phase retarder 50 is attached to the first lens 10, the polarization reflective element 60 is attached to the second lens 20, and the polarization element 70 is attached to the third lens 30.

That is, in the embodiment of the present invention, the first retarder 50, the polarization reflection element 60, and the polarization element 70 may be attached to the three different optical lenses, respectively, so as to separate the three optical elements. The three optical elements are not stacked together to form a layer structure. Thus, by adjusting the optical lenses, the alignment errors of the first retarder 50, the polarization reflecting element 60, and the polarization element 70 can be adjusted, and the introduction of stray light can be avoided as much as possible, thereby minimizing the stray light.

As shown in fig. 4, a schematic diagram of the optical module with minimal stray light is shown. The camera 02 is located at the left side of the optical module, and the stray light ratio of the optical module can be captured by the camera 02. During assembly, the first lens 10, the second lens 20, and the third lens 30 in the optical module are assembled to a predetermined angle, the first retarder 50 is attached to the first lens 10, the polarization reflection element 60 is attached to the second lens 20, and the polarization element 70 is attached to the third lens 30, on the basis, a certain angle (e.g., 0.1 °) is provided between the first lens 10, the second lens 20, and the third lens 30, a ghost ratio can be captured by rotation within a certain angle range (e.g., plus or minus 2 °), and finally the lenses are fixed in a state of minimum ghost, and the order of lens rotation may be that the first lens 10 and the third lens 30 are rotated, the second lens 20 is fixed, the case of minimum stray light is found, the first lens 10 is rotated to the angle, and the third lens 30 is rotated again, and the case of minimum stray light is found finally.

In some examples of the present invention, as in fig. 1-4, and fig. 9, the first lens 10 includes a first surface 11 and a second surface 12; the second lens 20 includes a third surface 21 and a fourth surface 22; the third lens 30 includes a fifth surface 31 and a sixth surface 32;

wherein the second surface 12 is disposed adjacent to the third surface 21, and the fourth surface 22 is disposed adjacent to the fifth surface 31; as shown in fig. 2 and 3, the first retarder 50 is attached to the second surface 12, the polarization reflective element 60 is attached to the third surface 21, and the polarization element 70 is attached to the fifth surface 31.

Optionally, as shown in fig. 2, a first anti-reflection film 91 may be further attached to the second surface 12 of the first lens 10, that is, the surface on which the first phase retarder 50 is attached, and on the basis of this, the first anti-reflection film 91 and the first phase retarder 50 are stacked to form a film structure on the second surface 12.

Alternatively, as shown in fig. 3, a second anti-reflection film 92 may be attached to the fifth surface 31 of the third lens 30, i.e., the surface on which the polarizer 70 is attached, and then the second anti-reflection film 92 and the polarizer 70 may be stacked to form a film structure on the fifth surface 31.

Furthermore, the antireflection film may be respectively attached on the fourth surface 22 of the second lens 20 and the sixth surface 32 of the third lens 30, and for this, a person skilled in the art may flexibly adjust the antireflection film according to needs, which is not limited in the embodiment of the present invention.

For example, antireflection films are disposed on both optical surfaces of the third lens 30, so that light incident through the second lens 20 can be transmitted through the third lens 30 and completely enter the human eye 01.

In some examples of the present invention, as shown in fig. 1, 4 and 9, the light splitting element 40 is disposed on one side of the first surface 11; alternatively, the light splitting element 40 is attached to the first surface 11.

The light splitting element 40 may be located at a suitable position between the first surface 11 of the first lens 10 and the light emitting surface of the display 80; alternatively, the light splitting element 40 is located at an appropriate position near the first surface 11 side of the first lens 10.

Of course, the light splitting element 40 may also be directly attached to the first surface 11 of the first lens 10, as shown in fig. 1, 4 and 9.

The position of the light splitting element 40 can be flexibly set by those skilled in the art according to the needs.

In the optical module of the embodiment of the present invention, the first phase retarder 50, the polarization reflective element 60 and the polarization element 70 are disposed at an interval, and the angle can be adjusted.

In some examples of the present invention, the center thickness T of the first lens 10 ₁ Is 3mm < T ₁ < 8mm, the center thickness T of the second lens 20 ₂ T is more than 2.5mm ₂ ＜6mm。

In some examples of the present invention, the optical power of the first lens 10

Is composed of

The focal power of the second lens 20

Is composed of

In some examples of the present invention, the third lens 30 has a center thickness T ₃ T is more than 2.5mm ₃ ＜6mm。

The embodiment of the present invention provides an optical module, for example, which can include three optical lenses, i.e. the first lens 10, the second lens 20 and the third lens 30. The first lens 10 is disposed at a suitable position on the side of the display 80 where the light is incident, i.e., on the side of the display. The incident light may first enter the first lens 10. The second lens 20 is located at a suitable position between the first lens 10 and the third lens 30. The first lens 10 and the second lens 20 may be used to fold incident light. The third lens 30 is located at a side close to the human eye 01, and the third lens 30 lenses the light passing through the second lens 20, and finally the light can be emitted and enter the human eye 01 to display an image.

The first surface 11 of the first lens 10 is aspheric, and the dispersing element 40 can be mounted thereon, and the second surface 12 is planar or aspheric, and the first phase retarder 50 and the first anti-reflection film 91 can be mounted on the second surface 12.

The third surface 21 of the second lens 20 is aspheric, and a polarization reflective element 60 can be attached thereon, and the fourth surface 22 of the second lens 20 is planar or aspheric, and an anti-reflection film can be attached on the fourth surface 22.

The fifth surface 31 of the third lens 30 is a plane or an aspheric surface, on which the polarizer 70 and the second anti-reflection film 92 can be attached, and the sixth surface 32 of the third lens 30 is an aspheric surface, on which another anti-reflection film can be attached.

In some examples of the present invention, the display 80 is configured to be capable of emitting circularly polarized light or linearly polarized light; when the light emitted from the light emitting surface of the display 80 is linearly polarized light, a second phase retarder is disposed between the light emitting surface of the display 80 and the first lens 10, and the second phase retarder is configured to convert the linearly polarized light into circularly polarized light.

In an embodiment of the present invention, the optical module may include a display 80, the light-emitting surface of the display 80 is provided with a protective glass 81, and the light-emitting surface of the display 80 may emit light toward the first lens 10.

In the embodiment of the present invention, the second phase retarder may be disposed on the light emitting surface of the display 80, or disposed at a suitable position between the display 80 and the first lens 10, or disposed at a suitable position near the light emitting surface of the display 80.

In some examples of the present invention, the reflectance of the light splitting element 40 is 47% to 53%.

For example, the light splitting element 40 may be a transflective film.

In some examples of the present invention, the refractive index n of the first lens 10, the second lens 20, and the third lens 30 is: n is more than 1.4 and less than 1.7; the first lens element 10, the second lens element 20, and the third lens element 30 have an abbe number v of: v is more than 20 and less than 75.

For example, the refractive index n of the first lens 10 ₁ Is 1.54, coefficient of dispersion v ₁ Is 56.3; refractive index n of second lens 20 ₂ Is 1.54, coefficient of dispersion v ₂ Is 56.3; refractive index n of third lens 30 ₃ Is 1.54, coefficient of dispersion v ₃ Is 56.3.

According to the utility model provides an optical module, the propagation of light is as follows:

as shown in fig. 1, the display 80 emits circularly polarized light, and after the circularly polarized light is transmitted through the protective glass 81 on the light emitting surface of the display 80, the circularly polarized light is transmitted through the first lens 10, reflected by the polarization reflective element 60 on the third surface 21 of the second lens 20, and then converted into linearly polarized light by the first phase retarder 50 on the second surface 12 of the first lens 10, reflected by the light splitting element 40 on the first surface 11, and transmitted through the second surface 12, the second lens 20, and the third lens 30, and then the light is incident into the human eye 01.

The optical module provided by the embodiment of the present invention is explained by two embodiments below.

Example 1

The utility model provides an optical module, as shown in fig. 1, the optical module includes beam splitting element 40, first phase retarder 50, polarization reflecting element 60 and polarization element 70, wherein, polarization reflecting element 60 is located between first phase retarder 50 and polarization element 70;

the optical module further comprises a first lens 10, a second lens 20, a third lens 30 and a display 80, wherein the second lens 20 is located between the first lens 10 and the third lens 30;

the first lens 10 includes a first surface 11 and a second surface 12, the second lens 20 includes a third surface 21 and a fourth surface 22, and the third lens 30 includes a fifth surface 31 and a sixth surface 32; wherein the second surface 12 is disposed adjacent to the third surface 21, and the fourth surface 22 is disposed adjacent to the fifth surface 31;

the beam splitting element 40 is attached to the first surface 11, the first phase retarder 50 is attached to the second surface 12, the polarization reflecting element 60 is attached to the third surface 21, and the polarization element 70 is attached to the fifth surface 31;

the ratio of the stray light energy of the optical module to the light energy emitted by the display 80 is less than 1%, that is, the stray light ratio of the optical module is less than 1%.

In the optical module provided in this embodiment 1, the optical parameters of the first lens element 10, the second lens element 20 and the third lens element 30 can be specifically as shown in table 1 below.

TABLE 1

Example 2

The utility model provides an optical module, as shown in fig. 9, the optical module includes beam splitting element 40, first phase retarder 50, polarization reflecting element 60 and polarization element 70, wherein, polarization reflecting element 60 is located between first phase retarder 50 and polarization element 70;

the beam splitting element 40 is attached to the first surface 11, the first phase retarder 50 is attached to the second surface 12, the polarization reflecting element 60 is attached to the third surface 21, and the polarization element 70 is attached to the fifth surface 31.

In the optical module provided in embodiment 2, the optical parameters of the first lens element 10, the second lens element 20 and the third lens element 30 can be specifically listed in table 2 below.

TABLE 2

The above-described embodiment 1 is different from the embodiment 2 in the optical parameters shown in the above-described tables 1 and 2.

Also, as shown in fig. 5 to 8, for embodiment 1 and embodiment 2:

fig. 5 is a schematic view of a dot array diagram of an optical module according to

embodiments

1 and 2 of the present invention, fig. 6 is a MTF curve graph of an optical module according to

embodiments

1 and 2 of the present invention, fig. 7 is a distortion graph of a field curvature according to

embodiments

1 and 2 of the present invention, and fig. 8 is a vertical axis chromatic aberration diagram according to

embodiments

1 and 2 of the present invention.

The point diagram is that after a plurality of light rays emitted by one point pass through the optical module, the intersection points of the light rays and the image plane are not concentrated on the same point any more due to aberration, so that a dispersion pattern scattered in a certain range is formed, and the imaging quality of the optical module can be evaluated. As shown in fig. 5, in example 1 and example 2, the maximum value of the image point in the dot array image was less than 10 μm, and the image was clearly formed.

The MTF graph is a modulation transfer function graph, and the imaging definition of the optical module is represented by the contrast of black and white line pairs. As shown in fig. 6, MTF >0.25 at 45lp/mm in example 1 and example 2, the imaging was clear.

The field curvature distortion map reflects the image plane position difference of clear images of different fields, and in the embodiment 1 and the embodiment 2, as shown in fig. 7, the maximum value of the field curvature occurs near the fields of 0.6 and 0.8, and the maximum value is less than 0.2mm; the distortion occurred at the maximum in 1 field of view in examples 1 and 2, with a maximum value of less than 30% (absolute).

The vertical axis chromatic aberration is also called as magnification chromatic aberration, and mainly refers to the difference of focal positions of blue light and red light on an image surface when a polychromatic main light of an object side is emitted to an image side and becomes a plurality of light rays due to chromatic dispersion of a refraction system. In example 1 and example 2, as shown in fig. 8, the maximum dispersion is 1 field position of the system, and the maximum chromatic aberration value of the optical module is less than 222 μm.

According to the utility model discloses on the other hand, still provide a wear display device, wear display device includes the casing to and as above-mentioned optical module.

Wear display device for example for VR head-mounted apparatus, including VR glasses or VR helmet etc. the embodiment of the utility model provides a do not do specific restriction to this.

The utility model discloses wear display device's concrete implementation can refer to above-mentioned each embodiment of display module assembly, no longer gives unnecessary details here.

In the above embodiments, the differences between the embodiments are described in emphasis, and different optimization features between the embodiments can be combined to form a better embodiment as long as the differences are not contradictory, and further description is omitted here in consideration of brevity of the text.

Although some specific embodiments of the present invention have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. An optical module, comprising a beam splitting element (40), a first phase retarder (50), a polarization reflective element (60) and a polarization element (70), wherein the polarization reflective element (60) is located between the first phase retarder (50) and the polarization element (70);

the optical module further comprises a first lens (10) and a second lens (20);

wherein the first lens (10) is located between the beam splitting element (40) and the first phase retarder (50), the second lens (20) is located between the polarizing reflective element (60) and the polarizing element (70), and the first phase retarder (50) and the polarizing reflective element (60) are located between the first lens (10) and the second lens (20).

2. The optical module according to claim 1, further comprising a display (80), wherein the light-splitting element (40) is located at a side of the display (80) from which light exits;

the ratio of stray light energy of the optical module to light energy emitted by the display (80) is less than 1%.

3. Optical module according to claim 1, characterized in that it further comprises a third lens (30), the second lens (20) being located between the first lens (10) and the third lens (30), the third lens (30) being configured for transmitting the light rays exiting through the second lens (20).

4. The optical module of claim 3, wherein the first retarder (50) is attached to the first lens (10), the polarizing reflective element (60) is attached to the second lens (20), and the polarizing element (70) is attached to the third lens (30).

5. The optical module according to claim 4, characterized in that said first lens (10) comprises a first surface (11) and a second surface (12);

the second lens (20) comprises a third surface (21) and a fourth surface (22);

the third lens (30) comprises a fifth surface (31) and a sixth surface (32);

wherein the second surface (12) is arranged adjacent to the third surface (21) and the fourth surface (22) is arranged adjacent to the fifth surface (31);

the first phase retarder (50) is attached to the second surface (12), the polarizing reflective element (60) is attached to the third surface (21), and the polarizing element (70) is attached to the fifth surface (31).

6. The optical module according to claim 5, characterized in that said light-splitting element (40) is arranged on one side of said first surface (11); alternatively, the first and second liquid crystal display panels may be,

the light splitting element (40) is attached to the first surface (11).

7. Optical module according to claim 1, in which the first lens (10) has a central thickness T ₁ Is 3mm < T ₁ < 8mm, the center thickness T of the second lens (20) ₂ T is more than 2.5mm ₂ ＜6mm。

8. Optical module according to claim 1, in which the optical power of the first lens (10)

Is composed of

The focal power of the second lens (20)

Is composed of

9. Optical module according to claim 3, characterized in that the third lens (30) has a central thickness T ₃ Is T of 2.5mm < T ₃ ＜6mm。

10. Optical module according to claim 2, in which the display (80) is configured so as to be able to emit circularly or linearly polarized light;

when the light emitted from the light-emitting surface of the display (80) is linearly polarized light, a second phase delay is arranged between the light-emitting surface of the display (80) and the first lens (10), and the second phase delay is used for converting the linearly polarized light into circularly polarized light.

11. An optical module according to claim 1, characterised in that the light-splitting element (40) has a reflectivity of 47% to 53%.

12. A head-mounted display device, comprising:

a housing; and

the optical module of any one of claims 1-11.