CN215117019U

CN215117019U - Optical lens group and near-to-eye display device

Info

Publication number: CN215117019U
Application number: CN202120730203.1U
Authority: CN
Inventors: 程德文; 汪希萌; 陈海龙; 王其为; 倪栋伟
Original assignee: Beijing Ned+ Ar Display Technology Co ltd
Current assignee: Beijing Ned+ Ar Display Technology Co ltd
Priority date: 2021-04-12
Filing date: 2021-04-12
Publication date: 2021-12-10
Anticipated expiration: 2031-04-12

Abstract

The utility model discloses an optical lens group, include: the PBS prism comprises a light incidence surface, a light collimation surface and a light emergence surface, and also comprises a polarization selection beam splitter which is positioned on a plane obliquely intersected with the light incidence surface in the PBS prism; image light enters the PBS prism from the light incidence surface; a reflecting mirror located at one side of the light collimating surface for reflecting and collimating the image light emitted from the light collimating surface; the image light reflected by the reflector passes through the PBS prism and then is emitted from the light emergent surface; at least one lens is located on a transmission path of the image light. The utility model provides an optical lens group combines the PBS prism through using the speculum, can the correction system aberration, improves the imaging quality. The near-to-eye display device using the optical lens group has a good imaging effect and is easy to popularize and use.

Description

Optical lens group and near-to-eye display device

Technical Field

The utility model relates to an optical lens group relates to the near-to-eye display device who uses above-mentioned optical lens group simultaneously, belongs to the optical display equipment field.

Background

As the concept of Virtual Reality (VR) and Augmented Reality (AR) has been proposed, the market of near-eye display devices based on VR or AR modes has also been greatly developed. Among the hardware implementations that apply AR or VR technology, head-Mounted Display (HMD) and Near-Eye Display (NED) are the most efficient implementations that bring the best experience to the user in the prior art.

A near-eye display is a head-mounted display that can project an image directly into the eye of a viewer. The display screen of the NED is very close to human eyes and is smaller than the photopic vision distance, and the human eyes cannot directly distinguish the image content on the display screen. The image can be enlarged to a far distance through the NED optical system and is refocused on the retina of human eyes, so that the picture seen by the human eyes is as if the picture is beyond a few meters, and the display effect of AR and VR technology is achieved.

Since the near-eye display needs to be worn on the head of a person, it is important to have a small size and a good display effect. Waveguide display systems are one of the solutions for realizing near-eye display, but the size and weight of the projection system are too large due to the limitation of the size of the coupling end of the geometric waveguide.

Disclosure of Invention

The utility model aims to solve the first technical problem that provides an optical lens group.

Another object of the present invention is to provide a near-to-eye display device using the above optical lens assembly.

In order to realize the technical purpose, the utility model adopts the following technical scheme:

according to the utility model discloses an aspect provides an optical lens group, include:

a PBS prism comprising a light entrance surface, a light collimation surface, and a light exit surface, the PBS prism further comprising a polarization-selective beam splitter located within the PBS prism on a plane obliquely intersecting the light entrance surface; image light enters the PBS prism from the light incident surface;

a mirror positioned at one side of the light collimating surface for reflecting and collimating image light emitted from the light collimating surface; the image light reflected by the reflector passes through the PBS prism and then is emitted from the light emergent surface;

at least one lens located on a transmission path of the image light; the at least one lens includes a first lens located at one side of the light exit surface.

Preferably, the reflector is a spherical surface, an aspherical surface or a free-form surface.

Preferably, the at least one lens is a single lens, a cemented positive-negative lens, or a lens group formed by a plurality of lenses arranged in sequence.

Wherein preferably, the surface shape of the at least one lens is spherical or aspherical.

Preferably, the at least one lens further includes a second lens and/or a third lens, the second lens being located between the PBS prism and the mirror, and the third lens being located on one side of the light incident surface.

Wherein preferably, the mirror, the PBS prism, and the at least one lens are each rectangular in shape with a surface perpendicular to the optical axis of the image light, the rectangle having an aspect ratio greater than 3: 1.

preferably, the optical lens further comprises a diaphragm arranged at the exit pupil position of the optical lens group, and the diaphragm is used for limiting the rectangular exit pupil shape.

According to a second aspect of the embodiments of the present invention, there is provided a near-eye display device, comprising the above optical lens assembly, further comprising a micro-display and a waveguide system, wherein the micro-display is located at one side of the light incident surface and is used for emitting the image light; the waveguide system is vertical to a visual axis of a user, and the optical lens group and the micro display are sequentially arranged at the coupling end of the waveguide system; the waveguide system comprises an optical waveguide, the optical lens group is obliquely arranged relative to the optical waveguide, and an included angle between the optical axis of the first lens and the extension line of the optical waveguide is an acute angle.

Preferably, the waveguide system includes a prism and an optical waveguide, and the coupling end of the optical waveguide is coupled to the exit pupil of the optical lens group through the prism.

Preferably, the optical lens group is located on the same side of the extension line of the optical waveguide.

The volume of the optical lens group provided by the utility model can be reduced by adopting the PBS prism; through making PBS prism and speculum cooperation use, further rectify the aberration, improve the imaging quality, easily promote and use. The near-to-eye display device using the optical lens group is light in shape, small in size, good in display effect and wide in application range.

Drawings

Fig. 1 is a schematic structural diagram of an optical lens assembly provided in a first embodiment;

FIG. 2 is a schematic top view of the optical lens assembly shown in FIG. 1;

FIG. 3 is a schematic structural diagram of an optical lens assembly according to a second embodiment;

FIG. 4 is a schematic diagram of a near-eye display device including the optical lens assembly of FIG. 1;

fig. 5 is a schematic structural diagram of a near-eye display device including the optical lens group shown in fig. 3.

Detailed Description

The technical solution of the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It is obvious that the described embodiments are only some of the embodiments of the present invention, and not all of them. It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

The utility model provides an optical lens group, including PBS prism, speculum and at least one lens. Wherein the PBS prism is formed of a light wave transmissive material having a plurality of outer surfaces (including a light entrance surface, a collimating surface, a light exit surface, and other surfaces). The PBS prism also includes a polarization-selective beam splitter disposed within the PBS prism and located on a plane obliquely intersecting the light-entry surface. The polarization selective beam splitter can be implemented by plating a reflective film reflecting light of a specific polarization on the inclined surface inside the PBS prism.

In the following description, the arrangement of the PBS prism, the reflecting mirror, and the at least one lens is described in the optical axis direction of the image light. For ease of understanding, the entire lens group will be described with the image light traveling in a direction parallel to the paper as the viewing angle. However, the above arrangement is only used to illustrate the relative position of each optical element, and is not used to limit the arrangement and application of the lens set. It will be appreciated that in practical applications, the optical lens assembly as a whole may be rotated with respect to the orientation described below.

An image light source (e.g., using a microdisplay) is disposed on one side of the light-incident surface for emitting image light that enters the PBS prisms from the light-incident surface. According to different light path designs, different surfaces of the PBS prism correspondingly become a light emergent surface and a light collimation surface.

The reflector is arranged on one side of the light collimation surface and used for reflecting and collimating the image light emitted from the light collimation surface and eliminating aberration. The image light emitted from the light collimating surface may be p-type polarized light transmitted through the polarization selective beam splitter, or s-type polarized light reflected by the polarization selective beam splitter, depending on the specific optical path design. The mirror may be spherical, aspherical or free-form. Preferably, the mirror has an aspherical surface. The image light reflected by the mirror enters the PBS prism, passes through the PBS prism (which may be transmitted through or reflected by the polarization selective beam splitter), and then exits the light exit surface.

At least one lens is located on a transmission path of the image light. The at least one lens at least comprises the first lens positioned on one side of the light emergent surface of the PBS prism, and the imaging quality of the large-size exit pupil image can be remarkably improved by arranging the first lens. Meanwhile, the first lens is arranged to adjust the focal power of the optical lens group, so that the transmission path of the image light from the PBS prism to the optical waveguide system can be prolonged. On the basis, the other lenses can be arranged on the whole transmission path of the image light according to the requirement of the light path to carry out aberration correction. For example, the at least one lens may further include a second lens positioned between the PBS prism and the mirror and/or a third lens positioned on the side of the light incident surface between the PBS prism and the image light source.

By arranging at least one lens in the optical lens group, aberration can be further eliminated, and imaging quality is improved. At least one lens may be a single lens, a cemented positive-negative lens, or a lens group formed by sequentially arranging a plurality of lenses. Using cemented positive-negative lenses, the color can be made achromatic. The profile of at least one lens may be spherical or aspherical.

The following embodiments provide two typical implementations of the optical lens group, which can present better imaging effect.

First embodiment

As shown in fig. 1, the entire optical lens group will be described by taking as an example the case where image light is incident from above and transmitted in a direction parallel to the paper surface, and the optical axes of the image light are all located in a vertical plane, which is denoted as a plane p. The orientation in this embodiment is only used to understand the relative position relationship of each optical element in the optical lens group, and does not limit the actual position of the entire optical lens group.

The optical lens group provided in this embodiment includes a first lens 21, a PBS prism 22, a reflecting mirror 23, and a second lens 24. Wherein, the image source 100 (specifically, a micro display) is arranged above the PBS prism 22, and the upper surface of the PBS prism 22 is a light incident surface 221; the right surface of the PBS prism 22 is taken as a light collimation surface 222, and the reflecting mirror 23 is arranged at the right side of the PBS prism 22; the left surface of the PBS prism 22 is a light exit surface 223, and the first lens 21 is disposed on the left side of the PBS prism 22.

In the present embodiment, among others, the first lens 21 is formed by positive-negative lens gluing; the lens 211 located on the left side is a positive lens formed of a material having a lower refractive index and a large abbe number than the negative lens; the lens 212 on the right side is a negative lens and is formed of a material having a larger refractive index and a smaller abbe number than the positive lens. To precondition the image light entering PBS prism 22, a second lens 24 is also provided between image light source 100 and PBS prism 22. The second lens 24 is formed by positive-negative lens gluing; the lens 241 on the lower side is a positive lens formed of a material having a lower refractive index and a large abbe number than the negative lens; the lens 242 located on the upper side is a negative lens and is formed of a material having a larger refractive index and a smaller abbe number than the positive lens. Therefore, the effects of correcting paraxial spherical aberration and reducing chromatic aberration are achieved.

The PBS prism 22 is a polarization splitting prism in which a light collimating surface (i.e., the right surface of the PBS prism 22 in fig. 1) is attached with a polarization-converting polarizer or a polarization-converting film. The reflective surface of the PBS prism 22 (i.e., the inclined surface 204 in the PBS prism 22 in fig. 1) is coated with a reflective film that reflects light of a particular polarization.

In the optical lens group shown in fig. 1, image light emitted from the image light source 100 enters the PBS prism 22 from the light incident surface 221 after passing through the second lens 24, and reaches the polarization selective beam splitter at the position of the inclined surface 204; the image light reflected by the polarization-selective beam splitter exits from the light collimating surface 222 to reach the mirror 23; the image light reflected by the reflecting mirror 23 enters the PBS prism 22, passes through the polarization selective beam splitter, and exits from the light exit surface 223; then, the optical lens passes through the first lens 21 to reach the exit pupil position.

In fig. 1, the surfaces of the cemented first lens 21 are, in order from left to right: a front surface 201, a bonding surface 202, and a back surface 203; the tilted surface of PBS prism 22 is surface 204; the reflective surface of mirror 23 is surface 205; the surfaces of the cemented second lens 24, from bottom to top, are: a lower surface 206, an adhesive surface 207, and an upper surface 208. The focal length f of the optical lens group satisfies: 5mm < f <20 mm.

The surface shapes of the first lens 21 and the second lens 24 may be spherical or aspherical. The mirror 23 may be spherical, aspherical or free-form.

Tables 1 and 2 show the design parameters of the optical surfaces of the lenses in the optical lens assembly, wherein the first lens 21 and the second lens 24 are both spherical, and the reflecting surface of the reflecting mirror 23 is aspheric.

TABLE 1 optical surface parameters of various surfaces in the first embodiment

TABLE 2 values of coefficients in the aspherical equation of the reflecting surface 205 of the mirror 23

Wherein, the aspheric equation is:

where c is the inverse of the radius of curvature, r is the radial distance of a point on the surface, k is the conic constant, and Ai is the high order term coefficient. The values of the various coefficients of the reflecting surface 205 of the mirror 23 are shown in table 2.

Fig. 2 shows a top view of the optical lens assembly shown in fig. 1, wherein the second lens element 24 is omitted. The image light is transmitted in a plane perpendicular to the paper surface, and at this time, the plane where the optical axis of the image light is located is a plane P perpendicular to the paper surface. With respect to the paper direction, the image light enters the inside of the PBS prism 22 from the light entrance surface 221, exits from the light collimating surface 222 on the right side after being reflected by the surface 204, then enters the inside of the PBS prism 22 again after being reflected by the mirror 23, exits from the light exit surface 223 of the PBS prism 22 through the surface 204, and finally reaches the exit pupil position through the first lens 21.

In the transmission process of the image light, the image light passes through the light incident surface 221, the inclined surface 204, the light collimating surface 222, the surface 205, the light collimating surface 222, the inclined surface 204, the light exiting surface 223, the surface 203, the surface 202, and the surface 201 in this order.

In order to obtain a rectangular exit pupil shape, all surfaces of each optical element (including the first lens 21, the PBS prism 22, the reflecting mirror 23, and the second lens 24) in the optical lens group perpendicular to the optical axis of the image light are rectangular in shape. The aspect ratio of the rectangle is at least greater than 3: 1.

as can be seen from the plan view shown in fig. 2, with a plane on which the transmission path of the image light is located as a reference plane (i.e., a horizontal plane shown in fig. 2, and a plane P indicated by a chain line), among the surfaces perpendicular to the optical axis of the image light, a side perpendicular to the reference plane P is taken as a long side L, and a side parallel to the reference plane P is taken as a wide side H. Wherein, the value range of the wide side H is preferably not more than 5.5 mm.

In fig. 2, the shape of the light entrance surface 221 can be seen, and a rectangular schematic is given by taking the light entrance surface 221 as an example. Wherein, preferably, the ratio of the long side L to the wide side H is 6: 1-9: 1. It will be appreciated that the PBS prism 22 is a rectangular solid with a smaller cross-section and a longer length. Wherein two side lengths of the cross section respectively correspond to the wide sides H of the light incident surface 221; the length of the PBS prism 22 is equal to the long side L of the light incident surface 221.

Corresponding to the PBS prism 22, in the image shown in fig. 2, the mirror 23 and the first lens 21 have a length close to the length of the PBS prism 22 in the plane shown in fig. 2, and a length that can cover all the rays of the image light; the mirror 23 and the first lens 21 have a width close to the side length of the cross section of the PBS prism 22 in the direction perpendicular to the paper surface, and a width that can cover all the rays of the image light.

Preferably, the optical lens group further comprises a diaphragm 26, the diaphragm 26 is disposed at an exit pupil position of the optical lens group, and the diaphragm 26 is used for defining a rectangular exit pupil shape.

Second embodiment

As shown in fig. 3, the entire optical lens group will be described by taking as an example the case where image light is incident from above and transmitted in a direction parallel to the paper surface. The orientation in this embodiment is only used to understand the relative position relationship of each optical element in the optical lens group, and does not limit the actual position of the entire optical lens group.

The optical lens group provided in this embodiment includes a first lens 31, a PBS prism 32, a reflecting mirror 33, a second lens 34, and a third lens 35. Wherein, the image source 100 (specifically, a micro display) is arranged above the PBS prism 32, and the upper surface of the PBS prism 32 is a light incident surface 321; the right surface of the PBS prism 32 is taken as a light collimation surface 322, and the reflecting mirror 33 is arranged at the right side of the PBS prism 32; the left surface of the PBS prism 32 is a light exit surface 323, and the first lens 31 is disposed on the left side of the PBS prism 32. Second lens 34 is disposed over PBS prism 34 between PBS prism 34 and image light source 100.

In the present embodiment, unlike the first embodiment, on the right side of the PBS prism 32, a third lens 35 is further provided, and the third lens 35 is disposed between the PBS prism 32 and the reflecting mirror 33. Air gaps are present between the PBS prism 32, the third lens 35, and the mirror 33. In the prior art, a structure exists in which a lens is arranged on one side of the light collimation surface of the PBS prism 32 only, and the surface of one side of the lens, which is far away from the PBS prism, is used as a reflection surface. For this reason, in this embodiment, by providing the third lens 35 and the reflecting mirror 33 at the same time on the light collimating surface side of the PBS prism 32, the reflecting mirror 33 is set to an aspherical surface type, and the above-described problem is overcome.

Wherein the first lens 31 is a positive lens, and the first lens 31 is formed of a material having a lower refractive index and a large abbe number than the negative lens. The second lens 34 is a positive lens formed of a material having a lower refractive index and a large abbe number than the negative lens; therefore, the effects of correcting paraxial spherical aberration and reducing chromatic aberration are achieved. The third lens 35 is a negative lens and is formed of a material having a larger refractive index and a smaller abbe number than the positive lens.

In the optical lens group shown in fig. 3, image light emitted from the image light source 100 enters the PBS prism 32 from the light incident surface 321 after passing through the second lens 34, and reaches the polarization selective beam splitter located at the inclined surface 303; the image light reflected by the polarization-selective beam splitter exits from the light collimating surface 322, passes through the third lens 35, and reaches the mirror 33; the image light reflected by the reflecting mirror 33 passes through the third lens 35 again, passes through the light collimating surface 322, and enters the PBS prism 32; then, the image light passes through the polarization-selective beam splitter, exits from the light exit surface 323, and passes through the first lens 31 to reach the exit pupil position.

In fig. 3, the surface of the first lens 31 is a front surface 301 and a rear surface 302 in order from left to right, the inclined surface of the PBS prism 32 is a surface 303, the surface of the third lens 35 is a front surface 304 and a rear surface 305 in order from left to right, the reflecting surface of the reflector 33 is a surface 306, and the surface of the second lens 34 is a lower surface 307 and an upper surface 308 in order from bottom to top.

The surface shapes of the first lens 31, the second lens 34 and the third lens 35 can be spherical or aspherical. The mirror 33 may be spherical, aspherical, or free-form. Focal length f of the optical lens group: 15mm < f <25 mm.

The present application provides a set of design parameters for each lens in the second embodiment. As shown in table 3, in this design, the surfaces of the first lens 31, the second lens 34, and the third lens 35 are all spherical, and the reflecting surface of the reflecting mirror 33 is aspherical.

TABLE 3 optical surface parameters of various surfaces in the second embodiment

	Type (B)	Radius of curvature	Thickness of	Refractive index	Abbe number
							301	Spherical surface	77.82	3.75	1.78	25.72
302	Spherical surface	-165.42
						303	Spherical surface	∞		1.72	29.51
304	Spherical surface	-45.82	1.5	1.92	18.90
						305	Spherical surface	-70.21
306	Aspherical surface	-58.20
						307	Spherical surface	20.38	4	1.68	55.6
308	Spherical surface	∞

TABLE 4 values of coefficients in the aspherical equation of the reflecting surface 306 of the mirror 33

Wherein the equation for the aspheric surface is:

where c is the inverse of the radius of curvature, r is the radial distance of a point on the surface, k is the conic constant, and Ai is the high order term coefficient. The values of the various coefficients of the reflecting surface 205 of the mirror 33 are shown in table 2.

Similarly, in the second embodiment, in order to obtain a rectangular exit pupil shape, all surfaces of each optical element (including the first lens 31, the PBS prism 32, the reflecting mirror 33, the second lens 34, and the third lens 35) in the optical lens group that are perpendicular to the optical axis of the image light are rectangular in shape. The description of the specific shape of the optical element is the same as that of the first embodiment, and is not repeated herein.

As will be understood in conjunction with the above two embodiments, in the optical lens group, the light incident surface and the light exit surface of the PBS prism are adjacent surfaces, so that the arrangement distance between the PBS prism and the optical waveguide system in the optical lens group is increased by arranging the first lens on the light exit surface side to change the optical power of the entire optical lens group.

In the above embodiments, the structure of the optical lens group provided in the present application is illustrated by taking the arrangement manner of the light collimating surface adjacent to the light incident surface as an example. The light collimating surface may also be arranged as a surface opposite the light entrance surface, depending on the specific light path design. In this case, a mirror is provided opposite to the image light source, and the image light transmitted through the polarization selective beam splitter is reflected by the mirror, enters the PBS prism, is reflected by the polarization selective beam splitter, and is emitted from the light exit surface. In the transmission process of the image light, the polarization type of the polarized light needs to be converted according to the light path design, and details are not described here.

The application also provides a near-eye display device using the optical lens group. Fig. 4 and 5 show two near-eye display devices, respectively.

Third embodiment

The embodiment provides a near-eye display device suitable for being used by glasses type near-eye display equipment. For convenience of description, the near-eye display device will be described below in a top view angle in actual use.

The near-to-eye display device shown in fig. 4 comprises a microdisplay 100 and the optical mirror assembly 200 of fig. 1, and further comprises a waveguide system 400. The microdisplay 100 is positioned on one side of the light incident surface 201 and the microdisplay 100 may use an OLED, LCOS, LCD type display. The waveguide system 400 is perpendicular to the user's visual axis, and the optical lens assembly 200 and the microdisplay 100 are sequentially arranged at the coupling end of the waveguide system 400. The waveguide system 400 comprises a light guide 401, the optical lens assembly 200 is arranged obliquely with respect to the light guide 401, and an angle between an optical axis of the first lens 21 and an extension of the light guide 401 is acute. Wherein the waveguide system 400 is disposed in the frame and the microdisplays 100 and the optical lens assembly 200 are disposed at the locations where the frame and temple are joined.

Preferably, the waveguide system 400 includes an optical waveguide 401 and a triangular prism 402. The optical waveguide 401 is an array optical waveguide, the optical coupling end of the optical waveguide 401 is a plane obliquely intersecting with the length direction of the optical waveguide, and image light is incident from the optical coupling end, then is totally reflected inside the optical waveguide 401, and is reflected out of the optical waveguide 401 by the plurality of semi-transparent and semi-reflective films. The light incoupling end of the light guide 401 is coupled to the optical mirror group 200 by a triangular prism 402. The light incident surface of the prism 402 is disposed at the exit pupil of the optical lens group to couple in the image light.

In the above structure, the matching angle of the triangular prism 402 can be selected according to the actual requirement of the near-eye display device, so that the whole optical lens group can be deflected relative to the optical waveguide. At this time, by controlling the vertex angle range of the triangular prism 402 and combining with the focal power control of the optical lens group, the optical lens group can be located on the same side of the extension line of the optical waveguide, and the outline of the outermost side of the optical lens group does not exceed the extension line of the optical waveguide 401.

Specifically, the deflection of the optical mirror group with respect to the optical waveguide 401 is realized by the triangular prism 402; by disposing the light entrance surface 221 and the light exit surface 223 of the PBS prism 22 as adjacent surfaces, the microdisplay 100 is positioned in a region between the PBS prism 22 and the extension line of the light guide 401; the distance between the PBS prism 22 and the optical waveguide system 400 is lengthened by the first lens 21, so that the PBS prism 22 and the microdisplay 100 are farther away from the extension line of the optical waveguide, and the optical lens group can be ensured to be located on the same side of the extension line of the optical waveguide 401 as a whole. Preferably, by disposing the second lens 24 between the light incident surface 221 of the PBS prism 22 and the microdisplay 100, the disposition distance of the microdisplay 100 is adjusted so that the profile of the microdisplay 100 does not exceed the extension line of the light guide 401.

Meanwhile, through the arrangement, the distance between the whole optical lens group and the visual center position (namely the visual axis) of the optical waveguide is further increased, and the adaptive distance of the optical lens group is increased. The distance S between the lowest end of the outer contour of the entire optical lens group on the side close to the optical axis of the optical waveguide (i.e. the position of the optical lens group on the side close to the optical axis and farthest from the optical waveguide) and the visual center position of the optical waveguide in fig. 1 is taken as the adaptive distance of the optical lens group, and the distance corresponds to the distance between the glasses legs and the glasses. The preferable value range of the distance S is 40-50 mm, and the distance can meet the use requirement of the near-eye display device in glasses near-eye display equipment.

In the near-eye display device shown in fig. 4, preferably, the distance between the microdisplay 100 and the optical mirror group 200 should be controlled within a small size range.

Fourth embodiment

The embodiment provides a near-eye display device suitable for being used by a head-mounted near-eye display device. For convenience of description, the near-eye display device will be described below in terms of a side view angle in actual use.

The near-to-eye display device shown in fig. 5 comprises the microdisplay 100 and the optical mirror assembly 300 of fig. 3, and further comprises a waveguide system 400'. Similar to fig. 4, the microdisplay 100 is positioned on one side of the light incident surface 301, and the microdisplay 100 may use an OLED, LCOS, LCD type display. The waveguide system 400 ' is perpendicular to the user's visual axis, and the optical lens assembly 300 and the microdisplay 100 are sequentially arranged at the coupling end of the waveguide system 400 '. Wherein the waveguide system 400 is placed in front of the eye and the microdisplay 100 and the optical lens assembly 300 are placed above the waveguide system 400, in an overhead position.

Preferably, the waveguide system 400 ' includes a light waveguide 401 ' and a triangular prism 402 ', and the light-coupling end of the light waveguide 401 ' is coupled to the exit pupil position of the optical lens group 300 through the triangular prism 402 ', so as to couple in the image light. The optical lens group 300 is disposed obliquely with respect to the optical waveguide 401 ', and an angle between an optical axis of the first lens 31 and an extension line of the optical waveguide 401' is an acute angle.

In the near-eye display device shown in fig. 5, depending on the specific structure of the optical waveguide, the human eye can see an image from the left side of the optical waveguide. When the optical waveguide is replaced so that the image is coupled out of the transflective film to the right side, the image can be seen by the human eye from the right side of the optical waveguide.

As can be understood from the foregoing embodiments, in the optical lens assembly provided in the present invention, on one hand, in order to obtain a rectangular exit pupil shape, the surfaces of the optical elements in the optical lens assembly perpendicular to the optical axis are rectangular, and the optical elements having a strip shape as a whole are designed; on the other hand, the transmission path of the image light is folded by combining the PBS prism and the reflecting mirror, and an optical lens group with extremely small volume is designed. The optical lens group is particularly suitable for near-eye display equipment of the glasses type.

Furthermore, the utility model provides a near-to-eye display device, including optical lens group and waveguide system, through using the exit pupil shape to cooperate for rectangular optical lens group and waveguide system, utilize the less optical lens group of volume, combine the ability of waveguide system one-dimensional expanding pupil, obtained great eyebox (eye movement district, eyebox district), for example: 10 mm. To sum up, the optical lens group provided by the present invention comprises a PBS prism and a reflector, wherein the volume of the optical system can be reduced by using the PBS prism; by using the PBS prism and the reflecting mirror in a matching way, aberration is further corrected, and imaging quality is improved. The near-to-eye display device using the optical lens group is light in shape, small in size, good in display effect and wide in application range.

The optical lens assembly and the near-to-eye display device provided by the present invention have been described in detail above. Any obvious modifications thereto, which would occur to one skilled in the art and which would not depart from the essence of the invention, would constitute a violation of the patent rights and would bear corresponding legal obligations.

Claims

1. An optical lens assembly, comprising:

2. The optical lens assembly of claim 1, wherein:

the surface of the reflector is a spherical surface, an aspherical surface or a free-form surface.

3. The optical lens assembly of claim 1, wherein:

the at least one lens is a single lens, a cemented positive-negative lens or a lens group formed by a plurality of lenses arranged in sequence.

4. The optical lens assembly of claim 1, wherein:

the surface shape of the at least one lens is spherical or aspherical.

5. The optical lens assembly of claim 1, wherein:

the at least one lens further includes a second lens positioned between the PBS prism and the mirror and/or a third lens positioned at a side of the light incident surface.

6. The optical lens assembly of claim 1, wherein:

the reflector, the PBS prism, and the at least one lens are all rectangular in shape on a surface perpendicular to an optical axis of the image light, and an aspect ratio of the rectangle is greater than 3: 1.

7. the optical lens assembly of claim 1, wherein:

the optical lens group further comprises a diaphragm arranged at the exit pupil position of the optical lens group, and the diaphragm is used for limiting the rectangular exit pupil shape.

8. A near-eye display device comprising the optical lens assembly of any one of claims 1 to 7, further comprising a waveguide system, the coupling end of the waveguide system being arranged in series with the optical lens assembly; the waveguide system comprises an optical waveguide, the optical lens group is obliquely arranged relative to the optical waveguide, and an included angle between the optical axis of the first lens and the extension line of the optical waveguide is an acute angle.

9. The near-eye display device of claim 8, wherein:

the waveguide system comprises a prism and an optical waveguide, and the coupling end of the optical waveguide is coupled with the exit pupil position of the optical lens group through the prism.

10. The near-eye display device of claim 9, wherein:

the optical lens group is positioned on the same side of the extension line of the optical waveguide.