阅读说明：本技术 消色差透镜、光学模组及vr佩戴设备 (Achromatic lens, optical module and VR wearing equipment ) 是由 刘明欢 麦英强 冯东洋 刘风雷 于 2019-09-20 设计创作，主要内容包括：本发明提供一种消色差透镜、光学模组及VR佩戴设备,属于光学显示成像技术领域,能够有效的减轻出光的色差缺陷,提高显示效果。消色差透镜包括第一透镜,第一透镜包括垂直于主光轴且相对设置的折射表面和二元光学表面,二元光学表面包括环带结构面以及在环带结构面上二元化形成的多个环阶,环阶的深度T满足：T＝h/2<Sup>n</Sup>；式中,h为环带的层厚,n为环阶的级次。(The invention provides an achromatic lens, an optical module and VR (virtual reality) wearing equipment, belongs to the technical field of optical display imaging, and can effectively alleviate the chromatic aberration defect of emergent light and improve the display effect. The achromatic lens comprises a first lens, the first lens comprises a refraction surface and a binary optical surface which are perpendicular to a main optical axis and are oppositely arranged, the binary optical surface comprises an annular belt structural surface and a plurality of annular steps formed in a binary mode on the annular belt structural surface, and the depth T of the annular steps meets the following requirements: t ═ h/2 n (ii) a In the formula, h is the thickness of the girdle, and n is the order of the ring steps.)

1. An achromatic lens, comprising a first lens including a refractive surface and a binary optical surface which are perpendicular to a main optical axis and are oppositely disposed, the binary optical surface including an annular zone structural surface and a plurality of annular steps dually formed on the annular zone structural surface, a depth T of the annular steps satisfying: t ═ h/2ⁿ；

In the formula, h is the thickness of the girdle, and n is the order of the ring steps.

2. An achromatic lens according to claim 1, wherein the annular structured surface comprises a plurality of annular zones concentrically arranged, the width of the plurality of annular zones gradually decreasing from the center to the edge so that the phase difference between two adjacent annular zones is an integral multiple of 2 pi.

3. An achromatic lens as in claim 1, wherein the annular structured surface is a fresnel diffractive annular surface.

4. An achromatic lens according to claim 1, characterised in that the refractive surface is convex.

5. An optical module comprising an achromatic lens according to any one of claims 1 to 4.

6. The optical module of claim 5, further comprising a beam splitter group comprising a first beam splitter and a second beam splitter arranged in sequence along a near-light source side of the achromatic lens, wherein a beam splitter layer is coated on a surface of the first beam splitter opposite to a surface of the second beam splitter, and wherein a distance between the first beam splitter and the second beam splitter is 2mm to 15 mm.

7. The optical module of claim 5 further comprising a polarizer assembly including a polarizer layer, a first 1/4 waveplate and a second 1/4 waveplate disposed in sequence on a near-source side of the achromatic lens, the polarizer layer having a transmission axis direction perpendicular to a polarization direction of the light source.

8. The optical module of claim 7 further comprising a first beam splitter disposed on a side of the polarizer group near the light source, wherein a surface of the first beam splitter is coated with a beam splitting film.

9. The optical module according to claim 7, further comprising a beam splitter group, the beam splitter group comprising a first beam splitter and a second beam splitter arranged in sequence, wherein the surfaces of the first beam splitter and the second beam splitter opposite to each other are respectively coated with a beam splitting film layer, and the beam splitter group is arranged on the near-light source side of the polarization layer of the polarizer group.

10. VR wearing apparatus comprising an optical module according to any of claims 5 to 9.

Technical Field

The invention relates to the technical field of optical display imaging, in particular to an achromatic lens, an optical module and VR (virtual reality) wearing equipment.

Background

Disclosure of Invention

The invention aims to provide an achromatic lens, an optical module and VR (virtual reality) wearing equipment, which can effectively alleviate the chromatic aberration defect of emergent light and improve the display effect.

The embodiment of the invention is realized by the following steps:

in one aspect of the embodiments of the present invention, an achromatic lens is provided, including a first lens, where the first lens includes a refractive surface perpendicular to a main optical axis and disposed opposite to the refractive surface, and a binary optical surface, the binary optical surface includes an annular band structure surface and a plurality of annular steps dualized on the annular band structure surface, and a depth T of the annular steps satisfies: t ═ h/2ⁿ(ii) a In the formula, h is the thickness of the girdle, and n is the order of the ring steps.

Optionally, the annular band structure surface comprises a plurality of annular bands concentrically arranged, and the widths of the annular bands are gradually reduced from the center to the edge, so that the phase difference between two adjacent annular bands is an integral multiple of 2 pi.

Optionally, the annulus structured surface is a fresnel diffractive annulus.

Optionally, the refractive surface is convex.

In another aspect of the embodiments of the present invention, an optical module is provided, which includes: the achromatic lens of any of the above.

Optionally, the optical module in the embodiment of the present invention further includes a beam splitter group, where the beam splitter group includes a first beam splitter and a second beam splitter that are sequentially disposed along a side of the achromatic lens close to the light source, and surfaces of the first beam splitter and the second beam splitter that are opposite to each other are respectively plated with a beam splitting film layer; wherein the distance between the first spectroscope and the second spectroscope is 2-15 mm.

Optionally, the optical module according to the embodiment of the present invention further includes a polarizer group, where the polarizer group includes a polarizing layer, a first 1/4 wave plate, and a second 1/4 wave plate sequentially disposed on a side of the achromatic lens near the light source, and a transmission axis direction of the polarizing layer is perpendicular to a polarization direction of the light source.

Optionally, the optical module according to the embodiment of the present invention further includes a first light splitter disposed on a side of the polarizing layer of the polarizer set, where a surface of one side of the first light splitter is plated with a light splitting film layer.

Optionally, the optical module of the present invention further includes a beam splitter group, the beam splitter group includes a first beam splitter and a second beam splitter arranged in sequence, the surfaces of the first beam splitter and the second beam splitter opposite to each other are respectively coated with a beam splitting film layer, and the beam splitter group is arranged on the light source side of the polarization layer of the polarizer group.

In another aspect of the embodiments of the present invention, there is provided a VR wearing apparatus including: the optical module of any of the above.

The embodiment of the invention has the beneficial effects that:

the achromatic lens provided by the embodiment of the invention comprises a first lens, wherein the first lens comprises a refraction surface and a binary optical surface which are vertical to a main optical axis and are oppositely arranged, the binary optical surface comprises an annular band structure surface and a plurality of annular steps formed on the annular band structure surface in a binary mode, and the depth T of the annular steps meets the following requirements: t ═ h/2ⁿ(ii) a In the formula, h is the thickness of the girdle, and n is the order of the ring steps. The refraction surface and the binary optical surface are respectively arranged on two opposite sides of the first lens, and the imaging is subjected to integrated correction of positive dispersion and negative dispersion, so that the chromatic aberration of the system can be effectively eliminated only through the structure of the single lens, and the emergent light display effect is improved.

The optical module provided by the embodiment of the invention adopts the achromatic lens, can effectively eliminate the chromatic aberration of the system through the refraction surface of the single lens structure and the binary optical surface, and improves the emergent light display effect.

The VR wearing equipment provided by the embodiment of the invention adopts the optical module, has better achromatism capability, better display effect, compact light path structure, smaller integral structure volume and convenient wearing and use, and can improve the film watching experience of users.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

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

FIG. 2 is a schematic diagram of an imaging position of each color light after the RGB three-color mixed white light passes through a refraction lens for achromatic color;

FIG. 3 is a schematic diagram of the imaging position of each color light after the RGB three-color mixed white light is achromatic by the diffraction lens;

FIG. 4 is a diagram of the position of the color light after the RGB three-color mixed white light passes through the achromatic lens according to the embodiment of the present invention;

FIG. 5 is a schematic diagram of a simulated optical path of an achromatic lens provided in an embodiment of the present invention;

fig. 6 is a simulation diagram of the superposition effect of each color spot at each view field position after the color difference is eliminated by the achromatic lens provided by the embodiment of the present invention;

FIG. 7 is a graph illustrating the shift of various colors of light after chromatic aberration is removed by the achromatic lens according to the embodiment of the present invention;

fig. 8 is a schematic diagram of a simulated optical path of an optical module according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of an exemplary simulated optical path of another optical module according to an embodiment of the present invention;

FIG. 10 is a schematic diagram of an exemplary simulated optical path of another optical module according to an embodiment of the present invention;

fig. 11 is a schematic diagram of a simulated optical path of another optical module according to an embodiment of the present invention.

Icon: 10-a first lens; 11-a refractive surface; 12-a binary optical surface; 121-annulus structural plane; 122-ring step; 20-a beam splitter group; 21-a first beam splitter; 22-a second beam splitter; 30-a polarizer group; 31-a polarizing layer; 32-first 1/4 wave plate; 33-a second 1/4 wave plate; r-red light; g-green light; b-blue light; t-the depth of the ring step 122; d-the width of the annulus; h-layer thickness of the annulus; n-order of the ring steps 122.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

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, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships conventionally found to be used in products of the present invention, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Fig. 1 is a schematic structural diagram of an achromatic lens provided by the present invention, and referring to fig. 1, an embodiment of the present invention provides an achromatic lens, including: a first lens 10, the first lens 10 including a refractive surface 11 and a binary optical surface 12 perpendicular to a main optical axis and disposed opposite to each other, the binary optical surface 12 including an annular zone structure surface 121 and a plurality of annular steps 122 dually formed on the annular zone structure surface 121, a depth T of the annular step 122 satisfying:

T＝h/2ⁿ (1)；

where h is the thickness of the girdle and n is the order of the steps 122.

First, the schematic structural diagram of the achromatic lens in the embodiment of the present invention shown in fig. 1 is a cross-sectional view of the first lens 10, and in a general case, the first lens 10 is circular, the refractive surface 11 shown in fig. 1 is a plane, and the annular zone structure surface 121 is a fresnel diffraction annular surface composed of fresnel diffraction rings, which are all exemplified in a specific realizable manner, and in the achromatic lens in the embodiment of the present invention, the refractive surface 11 and the annular zone structure surface 121 of the first lens 10 can only adopt the structure shown in fig. 1. The sectional shape of the annular zone constituting the annular zone structured surface 121 may be, for example, a triangular shape, a sinusoidal shape, or the like, in addition to the structure of the fresnel diffraction ring as shown in fig. 1. The ring-shaped structure surface 121 formed by the fresnel diffraction ring is described below as an example and illustrated.

Secondly, in the embodiment of the present invention, the specific form of the annular zone is not limited, and the annular zone structure surface 121 is a surface on which the annular structure is formed on the surface of the first lens 10. The binary optical surface 12 is a structure in which a plurality of annular steps 122 are formed on the annular band structure surface 121 in a binary manner, the annular steps 122 can be clearly defined by setting the names of the annular steps, the annular steps are annular stepped structures which are concentrically sleeved on the annular band structure surface 121, the depth of the steps gradually decreases from the center to the outer periphery, wherein the depth T of the annular steps 122 needs to satisfy the equation relation of the formula (1), h is the layer thickness of the annular band, n is the order of the annular steps 122, and n is counted from the center of the first lens 10 to the outer periphery in sequence.

For the refraction and diffraction integrated achromat lens of the embodiment of the invention, the optical power phi of the optical path system_totComprises the following steps:

Φ_tot＝Φ_r+Φ_d (2)

wherein phi_rAnd phi_dThe powers of the refractive element (refractive surface 11) and the diffractive element (binary optical surface 12), respectively.

If with D color light (lambda)_D0.587nm) as dominant wavelength, in F color (lambda)_F0.486nm) and C-color light (λ)_C0.656nm) to correct the chromatic aberration of the system, then:

wherein f 'is focal length with D color light as dominant wavelength in the system, and f'_r,Andthe focal length F 'of the D, F and C light beams of the refractive element'_d,Andthe focal lengths of the diffraction elements in the D color light, the F color light and the C color light are respectively.

The power distribution formula of the achromatic lens (first lens 10) is:

wherein, V_dAnd V_rThe abbe numbers of the diffractive element (binary optical surface 12) and the refractive element (refractive surface 11), respectively, are physical quantities that characterize the dispersive power of the optical element, i.e., the dispersion coefficients.

Thus, achromatic lens designs using both refraction and diffraction integration can theoretically eliminate chromatic aberration. The diffraction element with positive focal power (the binary optical surface 12) has negative dispersion, provides freedom for correcting chromatic aberration of the optical path system, can share the positive focal power of the optical path system, is favorable for reducing monochromatic aberration of the optical path system, and further improves image quality. For the binary optical surface 12 working based on diffraction, the depth T of the ring step 122 and the quantization order of the ring step 122 provide abundant degrees of freedom for the design of the optical path system, and provide a greater possibility for correcting chromatic aberration of the optical path system.

Specifically, taking the commonly used RGB (red, green, blue) three-color mixed white light source in the prior art as an example, the light source is incident from one side of the lens:

1. if the lens is only a refractive lens, as shown in fig. 2, the light source enters from the left side in the direction indicated by the arrow, and passes through the refractive lens, since the abbe number of the refractive optical element is a positive value, the positive dispersion coefficient causes different refraction angles of different colored lights in the emergent light, the blue light imaging position is closest to the refractive lens, the green light is secondly, and the red light imaging position is farthest from the refractive lens. The imaging positions of RGB are different, so that the color difference of emergent light imaging is obvious.

2. If the lens is only a diffractive lens, as shown in fig. 3, the light source enters from the left side in the direction indicated by the arrow, passes through the diffractive lens, and since the abbe number of the diffractive optical element is a negative value, the negative dispersion coefficient causes different diffraction angles of different colored lights in the emergent light, the imaging position of red light is closest to the diffractive lens, and then green light is located, and the imaging position of blue light is farthest from the diffractive lens. The imaging positions of RGB are different, so that the color difference of emergent light imaging is obvious.

The achromatic lens of the embodiment of the present invention adopts a single lens structure, two opposite surfaces of the first lens 10 perpendicular to the main optical axis are the refractive surface 11 and the binary optical surface 12, respectively, and the binary optical surface 12 functions as a diffraction surface by forming the annular step 122 on the annular zone structure surface 121 in a binary manner.

As shown in fig. 4, the light source is incident from the left side in the direction shown by the arrow, and by combining the refractive surface with positive dispersion coefficient and the diffractive surface with negative dispersion coefficient, the imaging positions of the different color lights on the image plane in the light passing through the achromatic lens according to the embodiment of the present invention are as close as possible, such as RGB imaging on the same position of the image plane in fig. 4, so as to perform a better achromatic effect.

The achromatic lens provided by the embodiment of the invention comprises a first lens 10, wherein the first lens 10 comprises a refraction surface 11 and a binary optical surface 12 which are perpendicular to a main optical axis and are oppositely arranged, the binary optical surface 12 comprises an annular band structure surface 121 and a plurality of annular steps 122 dualized on the annular band structure surface 121, and the depth T of the annular steps 122 satisfies that: t ═ h/2ⁿ(ii) a Where h is the thickness of the girdle and n is the order of the steps 122. The refraction surface 11 and the binary optical surface 12 which are respectively arranged on the two opposite sides of the first lens 10 are used for carrying out integrated correction of positive dispersion and negative dispersion on imaging, so that the chromatic aberration of the system can be effectively eliminated only through the structure of a single lens, and the emergent light display effect is improved.

Alternatively, as shown in fig. 1, the annular band structure surface 121 includes a plurality of annular bands concentrically arranged, and the widths d of the plurality of annular bands gradually decrease from the center to the edge, so that the phase difference between two adjacent annular bands is an integral multiple of 2 pi.

As shown in fig. 1, the width d of the ring zone refers to the width of the cross section of each ring zone, and the widths of the plurality of ring zones concentrically arranged in the ring zone structure surface 121 are different, wherein the width d of the ring zone closer to the center is larger, and the width of the ring zone closer to the edge is smaller, and the trend of gradually decreasing is shown, and the difference of the ring zone width d is based on the fact that the phase difference between two adjacent ring zones is an integral multiple of 2 pi. Therefore, all the annular zones concentrically arranged on the annular zone structural surface 121 satisfy that the phase difference between two adjacent annular zones is an integral multiple of 2 pi, and all the annular zones concentrically arranged are continuously changed from the center to the edge, and when a light source passes through the first lens 10, theoretically, incident light can be considered to be completely diffracted to the annular zone of the same order, so that the optimal diffraction capability is achieved. Alternatively, as shown in FIG. 1, the annulus structured surface 121 is a Fresnel diffractive annulus.

The Fresnel diffraction ring surface is an optical surface formed by a plurality of Fresnel diffraction rings on the surface of an optical element, the Fresnel diffraction ring surface is formed on the surface of the optical element, a basic Fresnel lens structure can be formed, the Fresnel lens has the function of correcting chromatic aberration, the ring-shaped structure surface 121 is set to be the Fresnel diffraction ring surface, the Fresnel diffraction ring surface has the function of correcting chromatic aberration to a certain degree, a plurality of ring steps 122 are further formed on the ring-shaped structure surface 121 which is the Fresnel diffraction ring surface in a binary mode, and the depth T of the ring steps 122 meets the following requirements: t ═ h/2ⁿThe achromatic effect of the binary diffractive surface formed is better.

Alternatively, as shown in fig. 5, in the achromatic lens according to the embodiment of the present invention, the refractive surface 11 of the first lens 10 is a convex surface.

As shown in fig. 5, the refractive surface 11 of the first lens element 10 is a convex surface structure, and the bending of the light due to the refraction provided by the convex surface structure is opposite to the dispersion of the light diffraction effect caused by the binary optical surface 12, so that the bending and the dispersion can be well offset, and compared with the refractive surface 11 with a planar structure, the chromatic aberration and the monochromatic aberration can be better corrected, thereby better achieving the correction effect.

Optionally, the refractive surface 11 and/or the binary optical surface 12 of the first lens 10 are coated with an antireflection film layer (not shown in fig. 1).

The antireflection film, also called an antireflection film, is plated on the optical surface of the optical element, and can reduce or eliminate the reflected stray light on the surface of the optical element, thereby increasing the light transmission amount of the optical element, reducing or eliminating the stray light of the system, and improving the light emitting display effect of the optical element.

The antireflection film layer is plated on the refraction surface 11 and/or the binary optical surface 12 of the first lens 10, so that the light energy utilization rate of the first lens 10 can be improved, stray light is reduced, ghost images in imaging are reduced, and the display effect is improved. The antireflection film layer is plated on the optical surface of the first lens 10, and an evaporation method, or physical vapor deposition, chemical vapor deposition, or the like may be adopted.

For example, as shown in fig. 5, a schematic diagram of a simulated optical path structure of an achromatic lens according to an embodiment of the present invention is shown, in fig. 5, a single lens structure of a first lens 10 is adopted, where the first lens 10 includes a refractive surface 11 and a binary optical surface 12, a light source enters the first lens 10 from the left side of fig. 5, and is imaged on a right image plane after exiting, where a diagonal field of view reaches 100 °, a total axial length (total axial length) of the system is 46.3 mm, and an antireflection film layer is plated on both the refractive surface 11 and the binary optical surface 12 of the first lens 10, so that an optical energy utilization rate of the optical path system is improved, and generation of ghost images is reduced.

In the achromatic lens according to the embodiment of the present invention, the light source should be incident from the right side as shown in fig. 5, the left side in fig. 5 is the near-eye side in the actual optical path, and both the near-light source side and the near-eye side defined in the present invention are defined in the actual optical path direction. For ease of understanding, the following description will be made in detail with reference to the drawings of the simulated optical path, and still to the direction of the simulated optical path.

As shown in fig. 6, it is found from the software simulation test results that when the diagonal field of view is 100 °, the color flare overlap at each field of view position is good, and the chromatic aberration correction effect is also good.

As shown in fig. 7, which is a graph showing the optical drift variation of each color (different wavelength bands) simulated by software, it can be seen from fig. 7 that the maximum focus drift is 113.0 μm, the diffraction limit value is 86.8 μm, and is very close to the theoretical limit value, and it can be seen that a better system chromatic aberration correction effect can be obtained by using the achromatic lens of the embodiment of the present invention, thereby effectively improving the display effect.

In another aspect of the embodiments of the present invention, an optical module is provided, which includes: the achromatic lens of any of the above.

The optical module provided by the embodiment of the invention adopts the achromatic lens, can effectively eliminate the chromatic aberration of the system through the refraction surface of the single lens structure and the binary optical surface, and improves the emergent light display effect.

Optionally, as shown in fig. 8, the optical module according to the embodiment of the present invention further includes a beam splitter group 20, where the beam splitter group 20 includes a first beam splitter 21 and a second beam splitter 22 sequentially disposed along a near light source side of the achromatic lens, and surfaces of the first beam splitter 21 and the second beam splitter 22 opposite to each other are respectively coated with a beam splitting film layer; wherein, the distance between the first spectroscope 21 and the second spectroscope 22 is between 2mm and 15 mm.

As shown in fig. 8, the optical module according to the embodiment of the present invention includes an achromatic lens (first lens 10), and a first beam splitter 21 and a second beam splitter 22 sequentially disposed on a low-beam side of the achromatic lens, wherein a light incident surface of the first beam splitter 21 and a light incident surface of the second beam splitter 22 are respectively coated with a beam splitting film layer (not shown in fig. 8), so that the first beam splitter 21 and the second beam splitter 22 can realize the function of light splitting transmission, the first beam splitter 21 and the second beam splitter 22 are arranged at intervals to form a beam splitter group 20, by the arrangement of the spectroscope group 20, the total length of the optical path of the optical module of the embodiment of the invention can be further shortened by further compressing the optical path on the basis that the achromatic lens is of a single lens structure (the first lens 10) so as to make the total length of the optical path shorter, thereby meeting the miniaturization requirement of the optical module and the optical product required by the optical module.

The distance between the first spectroscope 21 and the second spectroscope 22 in the spectroscope group 20 is set to be 2mm-15mm, so that the total length of the optical path of the optical module can be well adjusted, the total length of the optical path can be effectively shortened, the compactness of the optical module structure is improved, and the optical module provided by the embodiment of the invention is favorably applied to small-sized wearable display equipment. If the distance between the first beam splitter 21 and the second beam splitter 22 is smaller than 2mm, the difficulty in assembling and adjusting the first beam splitter 21 and the second beam splitter 22 in the optical module is increased, which affects the yield and the production efficiency of the optical module, and if the distance between the first beam splitter 21 and the second beam splitter 22 is larger than 15mm, the effect of the compression optical path of the beam splitter group 20 is weaker.

On the basis, more preferably, the distance between the first spectroscope 21 and the second spectroscope 22 in the spectroscope group 20 can be set to be 5mm-10mm, so that the total optical path length of the optical module according to the embodiment of the invention can be better shortened on the premise of not increasing the difficulty in assembly and adjustment, and the structural compactness of the optical module is improved.

Optionally, the transmittance of the light splitting film layer is between 10% and 90%.

The light splitting film layer can divide an incident light beam into two parts according to a certain characteristic requirement (such as wavelength, light intensity, incident angle and the like), wherein one part is transmitted by the light splitting film layer, and the other part is reflected or absorbed by the light splitting film layer. According to the proportion of the transmission light of the light splitting film layer in the incident light, the light splitting film layer can be set to different transmission proportions, the transmissivity of the light splitting film layer in the embodiment of the invention can be between 10% and 90%, and the skilled person can reasonably select the light splitting film layer within the range according to the specific requirements and corresponding limitations of the light path system in actual use.

Alternatively, as shown in fig. 8, the optical surfaces of the first spectroscope 21 and the second spectroscope 22 are respectively plated with antireflection film layers (not shown in fig. 8).

Similarly, because of the stray light inhibition capability of the antireflection film, the antireflection film may be plated on the light exit surface of the first beam splitter 21 and the light exit surface of the second beam splitter 22, so as to reduce or eliminate stray light in the optical module, reduce ghost images in imaging, and improve the light exit display effect of the optical module.

Note that, since the surfaces of the first spectroscope 21 and the second spectroscope 22 that face each other are plated with the spectroscopic film layer, in general, the antireflection film layer is plated on the surface of the side where the first spectroscope 21 and the second spectroscope 22 are away from each other.

Alternatively, as shown in fig. 9, the optical module of the present invention further includes a polarizer assembly 30, the polarizer assembly 30 includes a polarizing layer 31, a first 1/4 wave plate 32, and a second 1/4 wave plate 33, which are sequentially disposed on the near-light source side of the achromatic lens (first lens 10), and the transmission axis direction of the polarizing layer 31 is perpendicular to the polarization direction of the light source.

As shown in fig. 9, a polarizer assembly 30 is added on the low beam source side of the achromatic lens (the first lens 10), the polarizer assembly 30 includes a polarizing layer 31, a first 1/4 wave plate 32 and a second 1/4 wave plate 33 which are sequentially arranged, after chromatic aberration correction of the achromatic lens, light of a simulated light path first passes through the polarizing layer 31, the transmission axis direction of the polarizing layer 31 is perpendicular to the polarization direction of the light source, polarized light in the light source, which is perpendicular to the transmission axis direction, passes through the polarizing layer 31, so that the polarizing layer 31 filters the incident light into linearly polarized light with the same polarization direction, the linearly polarized light passes through the first 1/4 wave plate 32 to generate a phase delay, thereby changing the polarization state of the incident light, for example, converting the linearly polarized light into elliptically polarized light, the elliptically polarized light passes through the second 1/4 wave plate 33 again, and the transmitted light generates a phase delay again, therefore, the elliptically polarized light is converted back to linearly polarized light, the polarization direction of the converted linearly polarized light is 90 degrees different from that of the linearly polarized light before the linearly polarized light enters the first 1/4 wave plate 32, and the converted linearly polarized light is emitted to an image surface for imaging. Therefore, in the optical module according to the embodiment of the present invention, the stray light generated by multiple reflections between the polarizer set 30 is converted into the polarization direction by the phase retardation of the first 1/4 wave plate 32 and the second 1/4 wave plate 33, and cannot be emitted, so that the ability of the optical module according to the embodiment of the present invention to eliminate the stray light is further improved, the adverse effect of the stray light on the imaging display is reduced, and the display effect is improved.

Optionally, as shown in fig. 10, the optical module according to the embodiment of the present invention further includes a first beam splitter 21 disposed on a side of the polarizing layer 31 of the polarizer set 30 close to the light source, and a surface of one side of the first beam splitter 21 is plated with a beam splitting film layer.

The first beam splitter 21 is disposed on the low-beam source side of the polarization layer 31 of the polarizer set 30, for example, as shown in fig. 10, the first beam splitter 21 is disposed between the first 1/4 wave plate 32 and the second 1/4 wave plate 33 on the low-beam source side of the polarization layer 31, stray light is reflected between the polarization layer 31 and the first beam splitter 21, the reflected light beam is converted in polarization direction by the phase retardation of the first 1/4 wave plate 32 and is blocked by the polarization layer 31, and the stray light can be reduced or even eliminated, so that the ability of the optical module according to the embodiment of the present invention to eliminate the stray light is further improved, the adverse effect of the stray light on imaging display is reduced, and the display effect is improved.

In the optical module according to the embodiment of the present invention, as for the first beam splitter 21 disposed on the side of the polarizing layer 31 of the polarizer group 30 close to the light source, which side surface of the first beam splitter 21 the beam splitting film is plated on is not particularly limited, as long as the surface of one side thereof is plated on so that the first beam splitter 21 can split the light beam, and it is relatively preferable that the beam splitting film is plated on the near-to-eye side of the first beam splitter 21 close to the actual light path.

Optionally, as shown in fig. 11, the optical module according to the embodiment of the present invention further includes a beam splitter group 20 on the basis of the polarizer group 30, where the beam splitter group 20 includes a first beam splitter 21 and a second beam splitter 22 that are sequentially disposed, the surfaces of the first beam splitter 21 and the second beam splitter 22 that are opposite to each other are respectively coated with a beam splitting film, and the beam splitter group 20 is disposed on the near light source side of the polarizing layer 31 of the polarizer group 30.

In the optical module according to the embodiment of the present invention, the polarizer group 30 is provided on the low-beam source side of the achromatic lens (first lens 10), and the spectroscope group 20 is further provided on the low-beam source side of the polarizing layer 31 of the polarizer group 30. For example, as shown in fig. 11, the first beam splitter 21 and the second beam splitter 22 of the beam splitter 20 are disposed between the first 1/4 wave plate 32 and the second 1/4 wave plate 33, and the beam splitter 20 can compress the total length of the optical path of the optical module, the optical module according to the embodiment of the present invention can effectively eliminate the chromatic aberration defect of the optical path system in the achromatic lens, and through the arrangement of the polarizer set 30, the stray light in the optical path system is weakened or removed, the display effect of the optical module is improved, and at the same time, on the basis that the total length of the optical path is shorter because the achromatic lens is a single lens structure (the first lens 10), the total length of the optical path of the optical module of the embodiment of the invention is further shortened by further compressing the optical path through the arranged beam splitter group 20, thereby meeting the miniaturization requirement of the optical module and the optical product required by the optical module.

In another aspect of the embodiments of the present invention, there is provided a VR wearing apparatus including: the optical module of any of the above.

The VR (Virtual Reality in English) visual equipment comprises display equipment such as VR helmets, VR eyecups and VR glasses for presenting vivid Virtual images, covers the view of users to the outside, guides the users to enjoy the Virtual images and generates a sense of being in a Virtual environment. For example, in 3D display, different images are displayed on left and right eye screens of a display device, and after the human eyes acquire the information with the difference, stereoscopic vision is generated in the brain.

Taking the head-mounted VR glasses as an example, the appearance of the glasses is substantially the structure of the glasses, and after the user wears the head-mounted VR glasses, different display pictures can be presented on both eyes of the user, so that a real picture feeling and an immersion feeling are generated. Because adopt the wear-type other wearing formula structures, VR wears equipment when guaranteeing display effect, needs to reduce the size and the weight of its module as far as possible. The display effect is poor, the user is difficult to generate a sense of trust and a sense of immersion when using the device, and if the whole volume of the device is too large or the weight of the device is too heavy, the use experience of the user is also poor.

By adopting the optical module, the VR wearing equipment provided by the embodiment of the invention has the advantages that the optical module has better achromatic capability, so that the display effect of the image displayed by the optical module is better, the optical path structure of the optical module is compact, the whole volume is smaller, and the volume and the weight of the VR wearing equipment can be effectively reduced when the optical module is applied to the VR wearing equipment, so that the VR wearing equipment provided by the embodiment of the invention is convenient to wear and use, the display effect is good, and the use experience of a user can be effectively improved.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.