WO2022048661A1 - Near-to-eye display device - Google Patents

Abstract

A near-to-eye display device, comprising an optical machine (105) and a light guide framework (101). The optical machine (105) is used for generating target light rays; the light guide framework (101) comprises two or more light guide plates; the target light ray generated by the optical machine (105) is divided into light rays of multiple fields of view (FOVs); and each light guide plate transmits light rays of some of the FOVs. The number of times that the incident light hits a grating is reduced by means of the multiple light guide plates, thereby reducing the energy loss.

Description

A near-eye display device

This application claims the priority of the Chinese patent application with the application number 202010933633.3 and the invention titled "A near-eye display device" filed with the State Intellectual Property Office of China on September 7, 2020, the entire contents of which are incorporated into this application by reference .

technical field

The embodiments of the present application relate to the field of optics, and in particular, to a near-eye display device.

Background technique

Vision is the most important sense for humans to obtain information from the outside world, and its importance is much greater than other perceptions. In recent years, a variety of near-eye display devices have appeared in academia and industry. Although the technical means are different, these solutions are optimized and evolved along the direction of user experience, including large field of view, high resolution, high color gamut, and large eye movement range.

From the perspective of improving user experience, the light guide needs to be able to provide a large field of view (FOV) range. The FOV range is the range of the virtual screen that the user can see. For energy loss, see Fig. 5, the transverse dimension w of the entrance pupil grating area is related to the distance h between the exit pupil of the optical machine and the wave entrance pupil and the scanning angle θ. Wherein, w=2*h*tan(θ), and the scanning angle θ is the included angle between the light ray emitted by the scanner and the mid-perpendicular line of the entrance pupil grating. Taking an ordinary scanning system as an example, h=3mm, θ=20°, then the width of the grating in the entrance pupil area is w=2.2mm. According to the refractive index of 2, the thickness of the substrate is 0.8mm, and the calculation is based on the critical angle of total reflection of 30°. If the grating is not repeatedly touched, the maximum lateral dimension (wmax) of the grating cannot exceed 2*0.8*tan(30°)= 0.924, and the actual lateral size w=2.2mm, which is greater than twice the wmax, that is, the light transmits in the substrate, and needs to encounter the entrance pupil grating twice, and each time it encounters the coupled grating, there may be energy coupled cause energy loss.

Under the condition that other conditions remain unchanged, the larger the FOV range, the more times the incident light hits the grating for many times, and the incident light hits the grating for many times, which brings a lot of energy loss.

SUMMARY OF THE INVENTION

A first aspect of the embodiments of the present application provides a near-eye display device, including:

Optical machine and light guide structure, in which the light machine is used to generate target light, the target light is the light that needs to be transmitted by the near-eye display device, the light guide structure includes two or more light guide plates, and the target light is divided into multiple fields of view FOV. Light, each light guide plate transmits part of the light of the FOV, and each light guide plate of the light guide structure contains gratings.

The light guide structure includes multiple light guide plates, and the grating of each light guide plate transmits light in a partial FOV range, that is, the FOV range is divided into multiple parts, and the incident light is transmitted through multiple light guide plates. The total FOV range remains unchanged, and each light guide plate is responsible for The FOV range is reduced, reducing the number of times the target light hits the grating multiple times, thereby reducing the energy loss of the target light transmission.

Based on the first aspect of the embodiment of the present application, in the first embodiment of the first aspect of the embodiment of the present application, the light guide structure includes a light guide plate containing a two-dimensional grating, and the light guide plate in this embodiment is called the first light guide plate, The first light guide plate includes an entrance pupil grating, an exit pupil grating and a left and right turning grating, wherein the first light guide plate receives the light of the first FOV through the entrance pupil grating, the first FOV is the FOV corresponding to the first light guide plate, and the exit pupil The grating is used to export light, and the left and right turning grating is used for light transmission between the entrance and exit pupil gratings.

In the embodiment of the present application, a light guide plate containing a two-dimensional grating can also be used, and the left and right turning grating and the exit pupil are combined into a two-dimensional grating, which can reduce the transmission path of light in the light guide and help improve the system efficiency. The size of the light guide can be reduced.

Based on the first implementation of the first aspect of the embodiments of the present application, in the second implementation of the first aspect of the embodiments of the present application, the first light guide plate is the light guide plate closest to the optical machine in the light guide structure.

In the embodiment of the present application, the light guide plate closest to the optical machine adopts a two-dimensional grating, which can make the area of the central field of view (near the 0° field of view) reach the central area of the eyebox and eliminate dark stripes in the central image area .

Based on any one of the first aspect to the second implementation manner of the first aspect of the embodiments of the present application, in the third implementation manner of the first aspect of the embodiments of the present application, the number of light guide plates of the light guide structure and the FOV range are positive Correlation, the larger the FOV range, the more the number of light guide plates, on the contrary, the smaller the FOV range, the less the number of light guide plates.

In the embodiment of the present application, the number of light guide plates of the light guide structure can be flexibly selected according to the FOV range.

Based on any one of the implementation manners of the first aspect to the second implementation manner of the first aspect of the embodiments of the present application, in the fourth implementation manner of the first aspect of the embodiments of the present application, the light guide structure includes three light guide plates.

Based on the fourth implementation of the first aspect of the embodiments of the present application, in the fifth implementation of the first aspect of the embodiments of the present application, the three light guide plates of the light guide structure are the first light guide plate, the second light guide plate and the third light guide plate, respectively. For three light guide plates, the FOV angle of the target light ranges from (-W) degrees to W degrees, and the multiple FOVs are respectively the first to fifth FOVs, wherein W is a rational number not equal to 0. The first light guide plate transmits the light of the first FOV, and the FOV angle of the light of the first FOV ranges from (-W/5) degrees to (W/5) degrees; the second light guide plate transmits the second FOV and the first FOV. For three FOV rays, the FOV angle range of the second FOV light is (W/5) degrees to [(W/5)*3] degrees, and the FOV angle range of the third FOV light is [(-W/5) *3] degrees to (-W/5) degrees; the third light guide plate transmits the light of the fourth FOV and the fifth FOV, and the FOV angle range of the light of the fourth FOV is [(W/5)*3] degrees To W degrees, the FOV angle of the ray of the fifth FOV ranges from (-W) degrees to [(-W/5)*3] degrees.

In the embodiment of the present application, a method is provided that divides the FOV range into multiple parts, and each of the three light guide plates undertakes the transmission of 1 or 2 parts of the target light.

Based on any one of the first aspect to the fifth implementation manner of the first aspect of the embodiments of the present application, in the sixth implementation manner of the first aspect of the embodiments of the present application, the optical machine includes a laser and a scanner, and the scanner uses The light emitted by the scanning laser is sent to the light guide structure.

In the embodiment of the present application, the optomechanical may be an optomechanical based on the principle of a laser scanning system, and the optomechanical has high contrast, small size, and low power consumption.

Based on any one of the first aspect to the sixth implementation manner of the first aspect of the embodiments of the present application, in the seventh implementation manner of the first aspect of the embodiments of the present application, the opto-mechanical is a liquid crystal-on-silicon LCOS opto-mechanical or digital Light processing optomechanics.

In the embodiments of the present application, various types of optical machines are provided, which improves the flexibility of the solution.

Based on any one of the first aspect to the seventh implementation manner of the first aspect of the embodiment of the present application, in the eighth implementation manner of the first aspect of the embodiment of the present application, the maximum clip between the target light rays generated by the optomechanical The angle can be from 20 degrees to 60 degrees.

Based on any one of the first aspect to the eighth implementation manner of the first aspect of the embodiments of the present application, in the ninth implementation manner of the first aspect of the embodiments of the present application, the near-eye display device is augmented AR glasses, or virtual Implement VR glasses.

In the embodiments of the present application, two possible specific devices of the near-eye display device are provided, which improves the flexibility and practicability of the solution.

Based on the ninth implementation of the first aspect of the embodiments of the present application, in the tenth implementation of the first aspect of the embodiments of the present application, the optical machine may be located in the mirror frame.

Based on any one of the embodiments from the first aspect to the tenth embodiment of the first aspect of the embodiments of the present application, in the eleventh embodiment of the first aspect of the embodiments of the present application, the distance between the optical machine and the light guide structure is 1 to 10 mm.

Based on any one of the implementation manners of the first aspect to the eleventh implementation manner of the first aspect of the embodiments of the present application, in the twelfth implementation manner of the first aspect of the embodiments of the present application, the target light rays are red, green, and blue RGB light.

A second aspect of the embodiments of the present application provides an optical information transmission method, including:

The light guide structure transmits the target light generated by the optical machine. The target light is the light that needs to be transmitted by the near-eye display device. The light guide structure includes two or more light guide plates. The target light is divided into multiple FOV lights. Each light guide plate To transmit part of the light of the FOV, each light guide plate of the light guide structure contains a grating.

The light guide structure includes multiple light guide plates, and the grating of each light guide plate transmits light in a partial FOV range, that is, the FOV range is divided into multiple parts, and the incident light is transmitted through multiple light guide plates. The total FOV range remains unchanged, and each light guide plate is responsible for The FOV range is reduced, reducing the number of times the target light hits the grating multiple times, thereby reducing the energy loss of the target light transmission.

Description of drawings

FIG. 1 is a schematic diagram of a near-eye display device in an embodiment of the present application;

FIG. 2 is another schematic diagram of a near-eye display device in an embodiment of the present application;

3 is another schematic diagram of a near-eye display device in an embodiment of the present application;

4 is a schematic diagram of an optical machine entrance pupil light spot with a non-shared exit pupil in an embodiment of the application;

5 is a schematic diagram of escaping rays of light from an entrance pupil region in the embodiment of the application;

6 is a schematic diagram of the division of a field of view in an embodiment of the present application;

FIG. 7 is a schematic diagram of a light guide structure in an embodiment of the present application;

8 is a schematic diagram of a one-dimensional grating and a two-dimensional grating in an embodiment of the present application;

9A is a schematic structural diagram of a light guide plate in an embodiment of the present application;

9B is another schematic structural diagram of the light guide plate in the embodiment of the present application;

9C is another schematic structural diagram of the light guide plate in the embodiment of the present application;

10A is another schematic diagram of K-space analysis in the embodiment of the present application;

10B is another schematic diagram of K-space analysis in the embodiment of the application;

10C is another schematic diagram of K-space analysis in the embodiment of the application;

11A is another schematic structural diagram of the light guide plate in the embodiment of the present application;

11B is another schematic structural diagram of the light guide plate in the embodiment of the present application;

11C is another structural schematic diagram of the light guide plate in the embodiment of the present application;

12A is another schematic structural diagram of the light guide plate in the embodiment of the present application;

12B is another schematic structural diagram of the light guide plate in the embodiment of the present application;

12C is another schematic structural diagram of the light guide plate in the embodiment of the present application;

13 is a schematic diagram of a path of light in the light guide plate according to the embodiment of the application;

14 is a schematic diagram of another path of light in the light guide plate according to the embodiment of the application;

FIG. 15 is a schematic structural diagram of a liquid crystal-on-silicon optical machine in an embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application. In this application, "at least one" means one or more, and "plurality" means two or more. "And/or", which describes the association relationship of the associated objects, indicates that there can be three kinds of relationships, for example, A and/or B, which can indicate: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A, B can be singular or plural. The character "/" generally indicates that the associated objects are an "or" relationship. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (a) of a, b or c, can represent: a, b, c, a and b, a and c, b and c or a and b and c, where a, b and c can be It can be single or multiple. It is worth noting that "at least one item(s)" can also be interpreted as "one item(s) or more(s)".

It should be noted that, in this application, words such as "exemplary" or "for example" are used to represent examples, illustrations or illustrations. Any embodiment or design described in this application as "exemplary" or "such as" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present the related concepts in a specific manner.

The descriptions of the first, second, etc. appearing in the embodiments of the present application are only used for illustration and distinguishing the description objects, and have no order. any limitations of the examples.

1 shows a near-eye display (NED) device, the near-eye display device may be augmented reality (AR) glasses, or virtual reality (VR) glasses, etc., The specific device is not limited here.

Figure 1 takes AR glasses as an example. The device includes:

The light guide structure 101, the optical machine 105, the temple 108 and the mirror frame 109, etc.

The optical machine 105 is used to generate the target light. In this embodiment, a laser scanning system is used as the projection light machine. The optical machine 105 includes a laser 106 and a scanner 107 . Using the laser scanning system as the projector has the advantages of high contrast, small size and low power consumption. It can be understood that the optomechanical 105 may also be other systems, which are not specifically limited here. As shown in FIG. 2 , the optomechanical 105 is a liquid crystal on silicon (LCOS) optomechanical.

Referring to Figure 3, it is a schematic diagram of the AR glasses, which have two similar optical machines and light guide structures. The distance between the light machines and the light guide structures can be 1 to 10 mm, and the common distance is 2-3 mm.

The optical machine 105 can be placed on the mirror frame. In order to make full use of the space position of the temple 108, the driving control system of the laser 106 and the scanner 107 can also be placed on the temple 108, which is not limited here.

In the prior art, the light guide structure 101 only includes one light guide plate. As shown in FIG. 4 , for an optical machine that does not share an exit pupil (such as an optical machine of a scanning system), the light emitted by the optical machine has different exit pupil angles and exits at different angles. The light spots do not overlap, so that the light guide plate needs a large entrance pupil grating area, and the angle between the light rays emitted by the optomechanical is generally 20° to 60°. It is understandable that for different visual experience requirements, the light emitted by the optomechanical The included angle between the light rays is not limited, for example, the included angle can also be 80°.

Referring to FIG. 5 , the lateral dimension w of the entrance pupil grating region is related to the distance h between the exit pupil of the optical machine and the wave entrance pupil and the scanning angle θ. Wherein, w=2*h*tan(θ), and the scanning angle θ is the included angle between the light ray emitted by the scanner and the mid-perpendicular line of the entrance pupil grating. Taking an ordinary scanning system as an example, h=3mm, θ=20°, then the width of the grating in the entrance pupil area is w=2.2mm. For the light incident on the leftmost side of the grating (such as large-angle beam 2), according to the refractive index 2, the thickness of the substrate is 0.8mm, and the calculation is based on the total reflection critical angle of 30°. If the grating is not repeatedly touched, the transverse direction of the grating The maximum size (wmax) cannot exceed 2*0.8*tan(30°)=0.924, and the actual lateral size w=2.2mm, which is greater than twice the wmax, that is, the light transmits in the substrate and needs to encounter the entrance pupil grating twice , and every time the coupled grating is encountered, 30% of the energy may be coupled out, resulting in energy loss. When using thinner substrates and larger angles of incidence, energy losses are more severe. The refractive index n of the medium is equal to the ratio of "speed of light in vacuum (c)" to "phase speed of light in medium (v)", namely: n=c/v, for example, the refractive index of water is 1.33. Indicates that light travels 1.33 times faster in a vacuum than in water. In the study of the phenomenon of total reflection, the incident angle when total reflection just occurs, that is, when the refraction angle is 90 degrees, is a very important physical quantity, called the critical angle. The incident angle is the angle between the incident ray and the normal to the incident surface.

In order to reduce the number of times the incident light hits the grating, referring to FIG. 1 , an embodiment of the present application provides a near-eye display device. The light guide structure 101 of the device includes two or more light guide plates. In this embodiment, three light guide plates are used. For example, the light guide structure includes light guide plates 102 to 104 .

It can be understood that the light guide structure 101 can include other numbers of light guide plates, such as two light guide plates, and the specific number can be determined according to the actual application scenario. For example, when the FOV range is large, more light guide plates can be used to reduce The number of times the incident light hits the grating.

The target light is divided into multiple FOV rays, and each light guide plate transmits a part of the FOV rays. Light board.

Taking the three light guide plates of the light guide structure as the first light guide plate, the second light guide plate and the third light guide plate as an example, the FOV angle of the target light is in the range of (-W) degrees to W degrees, and the FOV of the multiple fields of view includes the first light guide plate. To the fifth FOV, W is a rational number not equal to 0. The first light guide plate transmits the light of the first FOV, and the FOV angle of the light of the first FOV ranges from (-W/5) degrees to (W/5) degrees; the second light guide plate transmits the light of the second FOV and the third FOV , the FOV angle range of the light of the second FOV is (W/5) degrees to [(W/5)*3] degrees, and the FOV angle range of the light of the third FOV is [(-W/5)*3] degrees to (-W/5) degrees; the third light guide plate transmits the light of the fourth FOV and the fifth FOV, the FOV angle of the light of the fourth FOV ranges from [(W/5)*3] degrees to W degrees, the fifth FOV The FOV angle of the ray of the FOV ranges from (-W) degrees to [(-W/5)*3] degrees.

6, assuming that W is 40, that is, the optical machine 105 is in the lateral direction (the direction parallel to the mirror frame), the maximum angle of the light that the optical machine 105 can output is 80 degrees, and the first light guide plate is the light guide plate 102, The second light guide plate is the light guide plate 103 , and the third light guide plate is the light guide plate 104 . The light guide plate 102 transmits the light of the FOV area 1, and the FOV area 1 is an area from -8 degrees to 8 degrees; the light guide plate 103 transmits the light of the FOV area 2-1 and the FOV area 2-2, and the FOV area 2-1 is from 8 degrees to 8 degrees. The area of 24 degrees, the FOV area 2-2 is the area of -24 degrees to -8 degrees; the light guide plate 104 transmits the light of the FOV area 3-1 and the FOV area 3-2, and the FOV area 3-1 is 24 degrees to 40 degrees area, the FOV area 2-2 is the area from -40 degrees to -24 degrees.

The light guide plates 102 to 104 in the light guide structure 101 may be a one-dimensional grating light guide plate or a two-dimensional grating light guide plate, and the specific number of times is not limited.

Referring to FIG. 8 , it is a schematic diagram of a one-dimensional grating and a two-dimensional grating. According to the array form of diffraction units, the one-dimensional grating is in the form of parallel multi-slits, and the two-dimensional grating is in the form of a plane network.

This embodiment is described by taking a two-dimensional grating as an example. In this embodiment, the two-dimensional grating is a grating that combines the left and right turning grating and the exit pupil into one grating, which can reduce the transmission path of light in the light guide and help improve system efficiency. , and at the same time, the size of the light guide can be reduced. Generally speaking, the light guide plate closest to the light machine (the light guide plate 102 in this embodiment) can use a two-dimensional grating, so that the area of the central field of view (near the 0° field of view) reaches the central area of the eyebox, Remove dark bars from the central image area.

FIG. 7 shows that light from different angles after passing through the exit pupil of the optical machine enters the corresponding entrance pupil area of the light guide structure. With reference to FIG. 6 , for example, the light in the FOV area 1 corresponds to the entrance pupil area 1 and the FOV area in the light guide plate 102 The light of 2-1 corresponds to the entrance pupil area 2-1 in the light guide plate 103, and so on. Since each entrance pupil area is only responsible for a small part of the FOV area, the grating size of the entrance pupil area can be made smaller, reducing the risk of energy loss caused by the coupled light hitting the entrance pupil area.

9A to 9C correspond to the grating arrangements of different light guide plates, wherein each light guide plate takes a two-dimensional grating as an example, including an entrance pupil area (ie an entrance pupil grating), a left and right turning grating and an exit pupil grating, the entrance pupil area of which is Corresponding to different incident FOV areas, referring to the figure in conjunction with FIG. 6, for the light of FOV area 1, the entrance pupil area 1 of the light entering the light guide plate is located in the central area of the light guide plate, as shown in FIG. 9A; for FOV areas 2-1 and 2 For the light rays of -2, the gratings that enter the light guide plate are the entrance pupil areas 2-1 and 2-2, as shown in Figure 9B; for the light rays of the FOV areas 3-1 and 3-2, they enter the gratings of the light guide plate For the entrance pupil regions 3-1 and 3-2, as shown in Figure 9C.

Gratings are typically formed by periodic subwavelength-scale refractive index modulations. The physical form is not limited to common surface gratings, but can also be binary optical gratings, blazed gratings, metal gratings, holographic volume gratings, and the like.

来表征，可以定义为

为光栅周期。光线的射线行为也可以用三维空间矢量表示。在K空间，光栅引起的光线方向改变可以利用矢量相加相减来描述，也即： For convenience, people usually use k-space, or wave-vector space, to understand and quantify the deflection behavior of gratings to light. Diffraction gratings are usually used with grating vectors

to characterize, it can be defined as

is the grating period. The ray behavior of light can also be represented by a three-dimensional space vector. In K space, the change of light direction caused by grating can be described by vector addition and subtraction, that is:

和

分别为光线偏折前和偏折后的波矢，m为衍射级，取值可正可负。 in

and

are the wave vectors before and after the deflection of the light, respectively, m is the diffraction order, and the value can be positive or negative.

10A to 10C correspond to the K-space analysis diagrams of the light guide plates 102 to 104 . When the wave vector is in the ring composed of n1 and n2, it can be introduced into the light guide plate for transmission. Taking Figure 10.A as an example, the light located in the central area is projected into the ring, where the light vector of the short wavelength FOV is Near the n1 ring, the light with the long wavelength FOV is near the n2 ring.

In practical applications, the entrance pupil grating and the turning grating can also be combined into a two-dimensional grating, and the exit pupil grating can be replaced with a two-dimensional grating, see Figure 11A to Figure 11C, the same entrance pupil grating can use a one-dimensional grating, the exit pupil grating For using a two-dimensional grating, see FIGS. 12A to 12C , and the specific grating arrangement is not limited here.

Referring to FIG. 13 , the light guide plate may have multiple diffractive optical functional regions. For example, for the light guide plate 102 using a two-dimensional composite grating, the light guide plate 102 includes grating region 1 to grating region 4 .

Among them, the grating area 1 (entrance pupil grating) is the light coupling area, which is responsible for receiving the light from the FOV area of a part of the optical machine, and coupling it into the light guide plate for transmission. The size and position of different coupling regions of different light guide plates directly correspond to different incident FOV regions.

The grating area 2 and the grating area 3 (left and right turning gratings) are left and right light turning areas. The light passing through the entrance pupil grating can change the direction of light transmission through different turning areas and enter the light coupling out area.

The grating area 4 (exit pupil grating) is a light coupling-out area. The incident light is diffracted by the non-zero-order grating, and the light in the light guide plate is coupled out of the light guide plate. The sum of the grating vector of all the paths that the incident light passes through from the coupling area of the light guide to the exit pupil area is zero to ensure that the projection vector directions of the incident light and the outgoing light on the plane of the light guide plate are consistent.

It can be understood that, a plurality of gratings pointing in different directions may be located on the same side surface of the light guide plate, or may be located on different side surfaces of the light guide plate.

FIG. 14 shows a schematic diagram of the path of the light in the range of the FOV area 1 in the light guide plate 102 . For the right ray FOV1a of the FOV area 1, when it is projected to the entrance pupil grating area 1, the diffraction angle generated by the grating is greater than the total reflection angle of the light guide plate 102, so that it is confined in the light guide for transmission. As shown in Figure 13, for a grating region 1 having a vector of two dimensions (two-dimensional grating), the FOV1a can travel left, right and longitudinally within the light guide.

Referring to Fig. 14, considering the position of the human eye and the angular deflection of FOV1a, it is mainly transmitted according to the second path in Fig. 14: coupled into the light guide through the grating area 1, and then enters the grating area 3 to the left, superimposing the grating area 3 to the direction After downloading the vector, it then enters the grating area 4 and superimposes the corresponding vector, and then couples out of the light guide and enters the human eye. Similarly, FOV1c mainly follows path one: grating area 1 -> grating area 2 -> grating area 4, and finally to the human eye. The light FOV1b in the central area of the FOV will reach the human eye through paths 1, 2 and 3 due to the existence of the two-dimensional grating in the entrance pupil area.

The above mainly describes the laser scanning system as the projector light machine, and the following describes the plane image source such as the LCOS light machine or the digital light processing (DLP) light machine as the projector light machine. The embodiment of this application only uses the LCOS light machine as the light machine. Example to illustrate:

Referring to Fig. 15, Fig. 15 is a working principle diagram of an LCOS opto-mechanical. The light emitted by the backlight source 1501 of the light engine is single-polarized light (the polarization state is P state or S state). This part is a system. A typical LCOS light engine includes light emitting diode (LED) + condenser (Condenser) +Micro lens array (mico lens array, MLA) + polarizer (Polarizer). The solution does not limit its implementation, and the light source may be a light emitting diode (LED), a laser diode (LD), or the like.

The polarizing beam splitter 1503 reflects the light from the backlight source 1501 to the image source 1502; after the LCOS modulation, the polarization state changes, and the reflected light is transmitted through the polarizing beam splitter (PBS) 1503, Then it reaches the lens 1504, and the light is modulated in the lens 1504, and finally all the light parallel output is realized at the exit pupil 1505, that is to say, the focal plane of the lens is at infinity. In this architecture, the optomechanical is typically placed on the frame, so a prism 1507 is required to turn the image toward normal incidence into the different light guide layers.

When the optical engine 105 is an LCOS optical engine, after the light enters the light guide structure, its trajectory is similar to that in the above-mentioned embodiment (the embodiment in which the optical engine 105 includes the laser 106 and the scanner 107 ), and will not be repeated here.

The light transmitted by the near-eye display device in the embodiment of the present application may be red green blue (red green blue, RGB) light, or may be other types of light, such as monochromatic light.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system, device and unit described above may refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the present application can be embodied in the form of software products in essence, or the parts that contribute to the prior art, or all or part of the technical solutions, and the computer software products are stored in a storage medium , including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, read-only memory), random access memory (RAM, random access memory), magnetic disk or optical disk and other media that can store program codes .

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: The technical solutions recorded in the embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions in the embodiments of the present application.

Claims (13)

A near-eye display device, comprising: optomechanical and light guide architecture; The optical machine is used to generate target light; The light guide structure includes two or more light guide plates, the target light is divided into light rays located in multiple FOVs, each light guide plate transmits light of one or more FOVs, and each light guide plate contains grating. The device of claim 1, comprising: The light guide structure includes a first light guide plate containing a two-dimensional grating, the first light guide plate includes an entrance pupil grating, an exit pupil grating and a left-right turning grating, and the first light guide plate receives a first FOV through the entrance pupil grating The first FOV is the FOV corresponding to the first light guide plate, the exit pupil grating is used for exporting light, and the left and right turning gratings are used for light transmission between the entrance pupil grating and the exit pupil grating. The device according to claim 2, wherein the first light guide plate is the light guide plate closest to the optical machine in the light guide structure. The device according to any one of claims 1 to 3, wherein the number of light guide plates of the light guide structure is positively correlated with the FOV range. The device according to any one of claims 1 to 3, wherein the light guide structure comprises three light guide plates. The device according to claim 5, wherein the three light guide plates of the light guide structure are a first light guide plate, a second light guide plate and a third light guide plate, and the FOV angle range of the target light is (-W ) degrees to W degrees, the plurality of field of view FOVs include the first to fifth FOVs, and the W is a rational number not equal to 0; The first light guide plate transmits the light of the first FOV, and the FOV angle of the light of the first FOV ranges from (-W/5) degrees to (W/5) degrees; The second light guide plate transmits the light of the second FOV and the third FOV, and the FOV angle of the light of the second FOV ranges from (W/5) degrees to [(W/5)*3] degrees, so The range of the FOV angle of the light of the third FOV is [(-W/5)*3] degrees to (-W/5) degrees; The third light guide plate transmits the light of the fourth FOV and the fifth FOV, the FOV angle of the light of the fourth FOV ranges from [(W/5)*3] degrees to W degrees, and the fifth FOV The FOV angle of the ray ranges from (-W) degrees to [(-W/5)*3] degrees. The device according to any one of claims 1 to 6, wherein the optical machine comprises a laser and a scanner, and the scanner is used to scan the light emitted by the laser and send it to the light guide structure. The device according to any one of claims 1 to 6, wherein the optomechanical is a liquid crystal-on-silicon LCOS optomechanical or a digital light processing optomechanical. The device according to any one of claims 1 to 8, wherein the maximum included angle between the target rays generated by the optical machine is 20 degrees to 60 degrees. The device according to any one of claims 1 to 9, wherein the near-eye display device is augmented reality AR glasses or virtual reality VR glasses. The device according to claim 9, wherein the optomechanical is located in the mirror frame. The device of claim 11, wherein the distance between the optomechanical and the light guide frame is 1 to 10 mm. The device according to any one of claims 1 to 12, wherein the target light is red, green and blue RGB light.

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