RU2719568C1 - Augmented reality device and method of its operation - Google Patents

Abstract

FIELD: augmented reality device.

SUBSTANCE: invention relates to display methods and augmented reality devices based on diffraction and holographic optical elements and enables to increase the visible field of view, compactness and reproduction efficiency. Display method comprises steps of: A) radiation from the projection system falls on the first diffraction grating expanding; B) diffraction of each of beams falling on the first grid, forms negative first diffraction order, zero diffraction order and first diffraction order; C) the zero diffraction order comes out of the spreading first waveguide and falls on the second waveguide; D) minus the first diffraction order and the first diffraction order are propagated in the first waveguide by total internal reflection (TIR), returning to the first grid, falling on it in different points that do not coincide with each other; diffraction is again undergone, each forming a new minus first diffraction order, a new zero diffraction order, a new first diffraction order; E) for each new minus first diffraction order, a new zero diffraction order, a new first diffraction order, steps (C)–(D) are repeated; F) each zero diffraction order falling on the second waveguide passes through the second waveguide to the second diffraction grating, wherein diffraction of each of beams falling on the second grid, forms a minus first diffraction order, a zero diffraction order and a first diffraction order, wherein the first diffraction order experiences the airfoil from the wall of the second waveguide opposite the wall of the second waveguide facing the eye, re-enters the second grid, forms a new minus first diffraction order, a new zero diffraction order and a new first diffraction order, at that said new zero diffraction order leaves waveguide in direction to eye.

EFFECT: disclosed is augmented reality device and method of its operation.

28 cl, 12 dwg

Description

Technical field

The present invention relates to augmented reality devices made on the basis of diffraction and holographic optical elements, and to methods for their functioning.

Description of the Related Art

Wearable augmented reality glasses (AR) are a personal device that can be used as an additional screen, for example, for smartphones or other electronic devices. For the mass consumer, it is necessary to develop augmented reality glasses devices with a wide field of view (FOV), low weight and cost, compactness and high resolution, such wearable devices can replace TVs and smartphones to the user.

The following requirements are imposed on augmented reality glasses systems:

- a wide field of view so that the human eye can cover the entire area that he sees, the possibility of superimposing virtual images on a large area;

- low weight;

- low cost;

- high resolution, high contrast, etc.

When such requirements are achieved, problems arise, for example, due to the fact that a wide field of view requires providing a wide area inside which the eye can see the entire image without loss. There are different approaches to achieve the requirements. Some approaches can provide a wide field of view, but cannot provide a wide area inside which the eye can see the entire image without loss. Other approaches can provide a wide area within which the eye can see the entire image without loss, but cannot provide a wide field of view.

It should be noted that classical systems in which multiplication of the exit pupil is not used have an input and output lattice (holographic (HOE) or diffraction (DOE)). Schematically, such systems work as follows. The projector forms an image at infinity, forming parallel beams, while an input hologram or an input diffraction element located on the waveguide is placed in the exit pupil of the projector, due to diffraction by such an element, parallel beams are introduced into the waveguide without violating their parallelism, due to the complete internal Reflection beams propagate in the waveguide and fall on the output diffraction element (HOE / DOE). In the prior art, only one diffraction order of radiation transmitted through the diffraction grating is used, in addition, in the known devices the input and output gratings are used only in one plane, therefore, the wide input field at the output turns into a narrow picture, which is not quite comfortable to consider, because, if the pupil of the eye is looking forward, only the central field of the image is clearly visible, while the parts of the image located at the edges represent a dark area, and if the pupil of the eye is displaced tsya in the vertical direction, the central part on the contrary will be presented dark area. That is, in known classical systems, the user can see only a narrow strip of the image.

The prior art Microsoft 'Hololens' solution system (available on the Internet: https://en.wikipedia.org/wiki/Microsoft_HoloLens) is known for augmented reality glasses, which solves the problem of a narrow field of view. In the first version of such a known system, each eye uses its own projection system, which uses an input diffraction grating, a rotary grating (or the first propagating grating) that propagates the radiation, partially rotates into the area of the output grating, then the radiation propagates along the propagating grating and reaches output diffraction grating, where a wide field of the image is formed, due to which the eye perceives the image not in a narrow area, but has a more comfortable wide field when moving and looking. However, the known system has a complex structure, since three diffraction gratings are used. In addition, the propagating diffraction grating is difficult to manufacture, that is, the system as a whole is difficult to manufacture, since the angle of inclination of the strokes of the propagating grating should be exactly 45 ° relative to the input and output diffraction gratings. The manufacturing process of the known system is complex and expensive, since in the manufacture of such systems there is a large percentage of the output of defective products.

The second version of the famous Microsoft 'Hololens' solution system (available on the Internet at https://www.microsoft.com/en-us/hololens/hardware and https://en.wikipedia.org/wiki/HoloLens_2) differs from the first version in that only one common projector for two eyes is used, which the user places between the eyes. In such an implementation of the known system, the field of view has limitations in two directions, since the strokes of the input and output diffraction gratings should be perpendicular to each other. Therefore, when the radiation is input, the field of view is limited horizontally, and when the radiation is output, the field of view is limited vertically, that is, the original image is cut off both on the sides, and above, and below.

A prior art system for dilating the exit pupil is described in US Pat. No. 7,764,413 B2 (NOKIA CORPORATION), published July 27, 2010. The known system comprises: an introductory diffraction grating having strokes arranged vertically; two propagating rotary diffraction gratings for the left and right eyes, the strokes of which are tilted at an angle of 60 ⁰ ; two output diffraction gratings having strokes arranged vertically. Such diffraction gratings with different slopes of strokes are difficult to combine with each other. The known system has large overall dimensions, since the input region and the radiation propagation region are not used for the eyes, that is, these regions must occupy a place outside the eyes.

The prior art system for expanding the exit pupil is described in US 8160411 B2 (NOKIA CORPORATION), published 04/17/2017. The document describes a modification of the previous system, in which it is proposed to use a different arrangement of diffraction gratings, the principle of operation remains the same. Among the disadvantages of this known system, one can also note the high cost, the difficulty in manufacturing, input and output of the image have different directions, as a result of which the device has large dimensions.

An optical waveguide device that dilates the exit pupil is described in the prior art, as described in US 20190004321 A1 (WAVE OPTICS LTD), published January 3, 2019. In the known device on three sides of the waveguide there are three diffraction gratings. One diffraction grating is an introductory diffraction grating, two other diffraction gratings are located on opposite parts of the waveguide and their strokes are crossed relative to each other. The radiation incident on the first diffraction grating partially diffracts at an angle to this grating and partially passes on. Once on the second grating, the radiation diffracts in the other direction and partially propagates along the waveguide. That is, diffraction gratings located on opposite sides of the waveguide propagate radiation in different directions. Such a system is also difficult to manufacture, since there are two diffraction gratings, whose grooves are inclined at an angle to each other.

In the prior art, diffraction / holographic gratings are located in the same plane or in parallel planes. In order to ensure both the propagation (expansion) of radiation, as well as the input and output of radiation, in the prior art, the input grating is usually rotated 90 ^° relative to the output grating ^, in addition, the propagating grating is always located between the input and output gratings, which complicates the production technique such devices.

SUMMARY OF THE INVENTION

A device for displaying augmented reality, which contains a projection system; an expanding first waveguide, on the first surface of which rays from the projection system are incident, wherein the expanding first waveguide comprises an expanding first diffraction grating; a second waveguide containing a second diffraction grating. Moreover, the expanding first diffraction grating and the second diffraction grating are located in different planes relative to each other so that the zero diffraction order emerging from the expanding first waveguide falls on the second waveguide. The angle at which the rays from the projection system fall on the expanding first waveguide and fall on the expanding first diffraction grating is in the range from 0 ° to 90 ° with respect to the normal to the surface of the expanding first waveguide. The strokes of the expanding first diffraction grating should be located along the projection onto the expanding first diffraction grating of the rays from the projection system. The acute angle between the projection of the main beam of the projection system onto the plane of the first waveguide and the line of strokes is in the range of ± 30 °. The expanding first diffraction grating may be located on a second surface of the expanding first waveguide, opposite the first surface of the expanding first waveguide, onto which radiation from the projection system is incident. Moreover, the expanding first diffraction grating may be reflective. The expanding first diffraction grating may be located on the first surface of the expanding first waveguide. The expanding first diffraction grating may be transmissive. The second surface of the expanding first waveguide, opposite to the first surface of the expanding first waveguide, onto which the radiation from the projection system is incident, may have a mirror coating. The expanding first diffraction grating may be located on the second surface of the expanding first waveguide, wherein the second surface of the expanding first waveguide may be a reflective surface. The second waveguide may include a radiation input region, an intermediate region from which the emitted radiation does not enter the pupil of the eye, an effective radiation output region from which radiation can enter the pupil of the eye when moving the pupil of the eye during viewing. In the intermediate region of the second waveguide, diffraction may not occur. In the second waveguide, the radiation input region can be performed with high diffraction efficiency, the intermediate region can be performed with low diffraction efficiency, and the useful radiation output region can be performed with low diffraction efficiency. In the second waveguide, the input region of radiation can be performed with high diffraction efficiency, the intermediate region can be performed with average diffraction efficiency, the area of useful output radiation can be performed with average diffraction efficiency. Moreover, in the second waveguide, the radiation input region can be performed with high diffraction efficiency, the intermediate region and the useful output region can be performed with gradient diffraction efficiency, that is, the low diffraction efficiency is gradually increasing. In the second waveguide, the radiation input region can be performed with high diffraction efficiency, the intermediate region can be performed with low diffraction efficiency, the useful output region can be performed with gradient diffraction efficiency, that is, the low diffraction efficiency is gradually increasing. The expanding first waveguide and the second waveguide can be made together in the form of a monolithic curved waveguide. The expanding first diffraction grating and the second diffraction gratings may be diffractive optical elements. The expanding first diffraction grating may be a diffractive optical element, the second diffraction grating may be a holographic element. The expanding first diffraction grating may be a holographic element, the second diffraction grating may be a diffractive optical element. The first and second diffraction gratings can be holographic elements. The boundary of the region of the expanding first waveguide, within which the expanding first diffraction grating is located, can be made in the form of a geometric figure, which is one of a rectangle, a polygon, or any geometric figure with indirect arcuate sides and can be symmetric or asymmetric.

Augmented reality glasses are proposed comprising an element for the left eye and an element for the right eye, each element for the left and right eye being a device for displaying augmented reality. Moreover, the element for the left eye is located separately from the element for the right eye, the second waveguide of the element for the left eye is located on a separate left frame of glasses, located above the left eye, and the second waveguide of the element for the right eye is located on a separate right frame of glasses, located above the right eye. Moreover, the element for the left eye can be combined with the element for the right eye, and the second waveguide of the element for the left eye is the second waveguide for the element for the right eye and is located on the common frame of the glasses located above the left eye and above the right eye. Moreover, the expanding first waveguide of each of the elements for the left and right eyes can be located on the side of the left and right eyes, respectively. Moreover, the projection system and the expanding first waveguide of the element for the left eye are the projection system and the expanding first waveguide for the element for the right eye, said projection system and the expanding first waveguide can be located on the side of the left or right eye.

A device for displaying augmented reality, comprising a projection system; a waveguide containing a diffraction grating, wherein the waveguide includes a radiation input region, an intermediate region from which the output radiation does not enter the pupil of the eye, an effective radiation output region from which radiation can enter the pupil of the eye when moving the pupil of the eye during viewing.

The method of the proposed device for displaying augmented reality is proposed, comprising stages in which:

A) the radiation from the projection system falls on the expanding first diffraction grating;

B) the diffraction of each of the rays incident on the expanding first diffraction grating forms minus the first diffraction order, the zero diffraction order and the first diffraction order;

C) the zero diffraction order leaves the expanding first waveguide and enters the second waveguide;

D) minus the first diffraction order and the first diffraction order propagate in the expanding first waveguide due to total internal reflection,

return to the expanding first diffraction grating, hitting it at various points that do not coincide with each other,

undergo diffraction again, each forming a new minus the first diffraction order, a new zero diffraction order, a new first diffraction order,

E) for each new minus the first diffraction order, the new zero diffraction order, the new first diffraction order, steps (B) - (D) are repeated;

E) each zero diffraction order incident on the second waveguide passes through the second waveguide to the second diffraction grating, and the diffraction of each of the rays incident on the second diffraction grating forms minus the first diffraction order, zero diffraction order and the first diffraction order, the first order diffraction experiences total internal reflection from the wall of the second waveguide, opposite to the wall of the second waveguide facing the eye, re-hits the second diffraction grating, forms a new minus the first th diffraction order, a new zero-order diffraction and the new first-order diffraction, wherein the said new zero diffraction order emerges from the waveguide in the direction of the eye.

Brief Description of the Drawings

The above and other features and advantages of the present invention are explained in the following description, illustrated by the drawings, in which the following is presented:

FIG. 1 shows an embodiment of an augmented reality display device in which an expanding first diffraction grating is deposited on a second surface of an expanding first waveguide, opposite to a first surface of an expanding first waveguide onto which radiation from a projection system is incident.

FIG. 2 depicts device options for displaying augmented reality.

FIG. Figure 3 shows a second waveguide with a second diffraction grating, conventionally divided into regions; the distribution of diffraction efficiency over regions is shown.

FIG. 4 depicts one embodiment of a device for displaying augmented reality, in which the second waveguide has an area in which diffraction does not occur.

FIG. 5 shows an embodiment of the invention in the form of a single curved monolithic waveguide.

FIG. 6 shows an embodiment of the invention in the form of a parallel expanding first waveguide and a second waveguide.

FIG. 7 (a, b, c) illustrates options for implementing augmented reality glasses.

FIG. 8a, 8b illustrate the operation of the expanding first waveguide with the expanding first diffraction grating.

FIG. 9 illustrates the arrangement of the cone of rays from the projection system relative to the strokes and the normal to the expanding first diffraction grating and the expanding first waveguide.

FIG. 10a illustrates an augmented reality device known in the art.

FIG. 10b illustrates the augmented reality device of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

This application describes: augmented reality device with a wide field of view and augmented reality glasses, made on the basis of the proposed device. The present invention allows to get rid of the limitations of the field of view when viewing the image both vertically and horizontally, that is, it allows to increase the visible field of view, field of eye movement, playback efficiency, in addition, the eyeglass system is compact and easy to manufacture, therefore, cheaper . This is achieved by the fact that the input and output diffraction gratings are combined into a single diffraction grating, and the planes of the diffraction grating for propagating (expanding) the radiation from the projection system and the diffraction grating for input / output into the waveguide are spatially separated.

It should be noted that holographic diffraction gratings can be used as diffraction gratings.

The following terms are used to describe the invention.

The field of the eye movement (Eye motion box (EMB)) is the area within which the eye, moving, can see the entire virtual image completely, without loss.

An expanding first waveguide containing an expanding first diffraction grating is a system that multiplies the exit pupil, that is, at the output from the expanding first waveguide, not one exit pupil is formed, but several that are located relative to each other either closely or at a distance. This formation of multiplied pupils provides a wide field of eye movement, allowing you to see the entire virtual image completely, without loss. By expanding or propagating a radiation beam is meant an increase in the width (transverse dimensions of the beam) without introducing distortions (aberrations).

The exit pupil (or the pupil of the optical system) is a paraxial image of the aperture diaphragm in the image space formed by the subsequent part of the optical system in the direct course of the rays. This term is well-established in optics. The main property of the exit pupil is that at any point there is an entire image field. By multiplying the exit pupil, thereby increasing its size, without resorting to increasing the longitudinal dimensions of the optical system. Classical optics allows you to increase the size of the exit pupil, but the longitudinal dimensions of the optical system increase, waveguide optics due to the multiple reflection of beams of rays inside the waveguide allows you to do this without increasing the longitudinal dimensions. The expanding first waveguide is essentially a conventional waveguide, and the expanding first diffraction grating is essentially a conventional diffraction grating, and the expanding properties are manifested when the conventional waveguide and dashes of a conventional diffraction grating are located at certain angles to the incident radiation, which will be discussed below.

Diffraction efficiency is a property of the diffraction grating, measured in percent or fractions of a unit, diffraction efficiency is the ratio of the energy contained in one of the diffraction orders relative to the energy incident on the diffraction grating. This term is established in the prior art.

In the present invention, the projection system is inclined at an angle relative to the expanding first waveguide with the expanding first diffraction grating. Moreover, the strokes of the expanding first diffraction grating when applied to the expanding first waveguide are oriented in such a way that part of the received diffraction orders of the incident radiation is directed along the waveguide, undergoing complete internal reflection. That is, radiation, having fallen on such an expanding diffraction grating, propagates in 3 directions, while “0”, “-1” and “+1” diffraction orders are formed. There are a lot of methods for creating diffraction gratings and all of them are well known from the prior art, for example, in the case of relief diffraction gratings, they can be applied by etching through masks or nanoimprinting, in the case of holographic diffraction gratings, they can be recorded by an interference pattern.

As an example, the theoretical range of angles between the waveguides (between the expanding first waveguide and the second waveguide) and the corresponding diffraction gratings (between the expanding first diffraction grating and the second grating) is ± 90 ° relative to the normal to the second waveguide. The range of surface periods of the expanding first diffraction grating is 1200-400 nm for visible color. The range of surface periods of the second diffraction grating is 700-200 nm. For the manufacture of the proposed device, you can use any suitable materials, such as, for example, glasses, polymers, crystals. It should be noted that for the present invention, the materials and parameters are not limited to those listed, which is obvious to any person skilled in the art, and listing all the options is not the purpose of the invention, since all options are obvious to a person skilled in the art.

In one embodiment of the invention, there is provided a device for displaying augmented reality, designed for one eye, schematically depicted in figure 1. The proposed device for displaying augmented reality can be used as a standalone device for one eye (monocular). When combining two such devices, for the right and left eye, a system is formed that allows the user to see the stereo image. Such a system can be used, for example, in augmented reality glasses, in helmets of augmented reality, etc.

The proposed device for displaying augmented reality contains (see figure 1):

projection system 1;

expanding the first waveguide 2, on the first surface of which the radiation from the projection system 1, formed by many rays,

moreover, the expanding first waveguide 2 contains an expanding first diffraction grating 2a;

a second waveguide 3 containing a second diffraction grating 3a, wherein the expanding first diffraction grating 2a and the second diffraction grating 3a, and therefore expanding the first waveguide and the second waveguide, are located in different planes relative to each other, at an angle from 0 ° to 180 ° relative to each other , the zero diffraction order leaves the expanding first waveguide at the same angle at which the rays hit the expanding first waveguide 2.

It should be noted that in the General case, the first and second waveguides are transparent to the user.

The same image can be used for each eye if a projection system is used with one on both eyes. In another case, each projection system can project its own image for each eye if separate projection systems and separate waveguides for each eye are used.

The projection system can be located both from the side of the first surface of the expanding first waveguide, and from the side of the second surface of the expanding first waveguide, which is opposite to the first surface of the expanding first waveguide.

Using the two proposed devices for displaying augmented reality, respectively, for the right and left eye, you can create glasses for displaying augmented reality.

Also, in one embodiment, a device for displaying augmented reality is proposed, which comprises an element for the right eye and an element for the left eye, each of which includes: a projection system, a waveguide containing a diffraction grating, the waveguide including a radiation input region, an intermediate the area from which the outgoing radiation does not enter the eye, the area of useful radiation output from which the radiation can enter the pupil of the eye when moving the pupil of the eye during viewing but images.

In one embodiment of the invention, the expanding first diffraction grating 2a may be located on a second surface of the expanding first waveguide, opposite the first surface of the expanding first waveguide onto which radiation from the projection system is incident, while the expanding first diffraction grating is placed on a reflective surface deposited on the second surface expanding first waveguide.

The expanding first diffraction grating 2a may be located on a first surface of the expanding first waveguide 2 onto which radiation from the projection system 1 is incident, as shown in FIG. 2, wherein the expanding first diffraction grating 2a is transmission. In this case, the second surface of the expanding first waveguide, opposite to the first surface of the expanding first waveguide, can have a mirror (reflective) coating 4. The mirror coating 4 can improve the efficiency of the expanding first waveguide 2 and the whole device. This embodiment of the expanding first waveguide avoids the loss of radiation that occurs when the diffraction grating is located on the second surface of the expanding first waveguide, opposite the first surface of the expanding first waveguide.

The expanding first diffraction grating 2a can be arranged in the expanding first waveguide (or on the surface of the expanding first waveguide depending on the method of forming the diffraction structure) so that the boundary of the region of the expanding first waveguide 2, within which the expanding first diffraction grating 2a is located, can form various geometric figures representing, for example, a rectangle, a polygon, or any geometric figure with indirect (arched) sides, and may be symmetric or asymmetric. Different border profiles affect the performance of the image and the uniformity of the image for the eye. The border profile can be selected depending on the tasks, for example, obtaining a given picture of the distribution of the image intensity in different places or compensating for uneven brightness of the image from the projection system over the field of view.

The second diffraction grating 3a may have different efficiencies in different areas. In combination with all elements of the device for displaying augmented reality, various configurations of diffraction efficiency can compensate for the unevenness of brightness in the field of view and increase the uniformity of the image that the eye sees.

As shown in figure 3, the entire region of the second waveguide, on which there is one input / output second diffraction grating 3a, can be arbitrarily divided into several areas: radiation input region (I); the intermediate region (II) from which the emerging radiation does not enter the eye; the area of useful output of radiation (III), from which radiation can enter the pupil of the eye when moving the pupil of the eye while viewing in the field of eye movement. In each of the embodiments of the invention shown in FIG. 3, said regions of the second diffraction grating are performed with different diffraction efficiencies.

The distribution of diffraction efficiency of each region of the second waveguide is shown schematically in the graphs (see figure 3).

Option (a) corresponds to:

in region I, the maximum diffraction efficiency (for the type of diffraction grating that is used) in the region of radiation input into the second diffraction grating, due to which the radiation emerging from the expanding first waveguide is introduced into the second waveguide using the second diffraction grating with the lowest losses (maximum diffraction efficiency provides high image brightness and, accordingly, a wide range of brightness settings for the user),

in region II, the minimum diffraction efficiency (in the ideal case, zero) in the intermediate region,

in region III, low diffraction efficiency in the field of useful radiation output, which ensures uniform image output (that is, uniform image brightness is ensured).

Option (b) corresponds to:

in region I, the maximum diffraction efficiency in the region of radiation input into the second diffraction grating, due to which the radiation emerging from the expanding first waveguide is introduced into the second diffraction grating with the lowest losses (maximum diffraction efficiency provides a high image brightness and a correspondingly wide range of brightness settings for user)

in regions II and III - the average diffraction efficiency (average relative to the maximum for the type of grating to be used, average means the intermediate value between the maximum and minimum) in the intermediate region and in the field of useful radiation output.

Option (s) corresponds to:

in region I, the maximum diffraction efficiency in the region of radiation input into the second diffraction grating, due to which the radiation emerging from the expanding first waveguide is introduced into the second diffraction grating with the lowest losses (maximum diffraction efficiency provides a high image brightness and a correspondingly wide range of brightness settings for user)

and in the intermediate region and the region of useful conclusion (in regions II and III) - gradient diffraction efficiency is ensured, that is, low diffraction efficiency in region II gradually increases in region III, such a distribution of diffraction efficiency increases the overall efficiency of the device, compared to option ( and).

Option (d) corresponds to:

in region I, the maximum diffraction efficiency in the field of introducing radiation into the second diffraction grating, due to which the radiation emerging from the expanding first waveguide is introduced into the second waveguide using the second diffraction grating with the lowest losses (maximum diffraction efficiency provides high image brightness and, accordingly, a wide range brightness settings for the user),

in region II - the minimum diffraction efficiency in the intermediate region,

in region III - in the field of useful output, gradient diffraction efficiency is ensured, that is, low diffraction efficiency is gradually increasing.

It was experimentally found that the implementation of the second waveguide according to option (d) is the most efficient, and option (b) is the easiest to manufacture.

Figure 4 shows one embodiment of the invention in which diffraction does not occur on the intermediate region II of the second waveguide 3, that is, on the intermediate region II of the second waveguide, the second diffraction grating is absent or has zero efficiency. This part does not carry any functional load for outputting radiation, in other words, the radiation in this part of the second waveguide does not exit the waveguide at all, and through full internal reflection passes further along the waveguide. Due to this, radiation losses are reduced, and accordingly, the efficiency of the device is increased, compared with the examples shown in figures 1 and 2, because all the same the radiation coming from this region of the second waveguide in the variants shown in figures 1 and 2 does not get into the eye user.

Figure 5 shows an embodiment of the invention in the form of one curved waveguide, that is, the expanding first waveguide 2 with the expanding first diffraction grating 2a is a part of the waveguide curved in one direction, and the second waveguide 3 with the second diffraction grating 3a is part of the same waveguide which is curved the other way. This option is very convenient in the manufacture of glasses based on a device for displaying augmented reality. The principle of operation of this embodiment is exactly the same as described above.

Figure 6 shows an embodiment of the invention in the form of a parallel expanding first waveguide 2 with an expanding first diffraction grating 2a and a mirror coating 4, and a second waveguide 3 with a second diffraction grating 3a. Such an arrangement of waveguides can be convenient when performing helmet-mounted systems of augmented reality.

The proposed device for displaying augmented reality can be used to implement augmented reality glasses, as shown in figure 7 (a, b, c).

In one of the configurations of augmented reality glasses (Fig. 7 a), the system for generating and transmitting the invention for the left eye (first element) is located separately from the system for generating and transmitting the invention for the right eye (second element), each of which contains its own projection system 1 and its expanding first waveguide 2 with an expanding first diffraction grating, the second waveguide 3 and the second diffraction grating 3a of the first element (for the left eye) are located on a separate left frame of glasses located al left eye and the second waveguide 3 and the second diffraction grating of the second element 3a (right-eye) are arranged on a separate frame the right points, located over the right eye. In such an embodiment, it is possible to provide a stereo image.

In one configuration of augmented reality glasses (FIG. 7 b), the first element (for the left eye) is combined with the second element (for the right eye). The second waveguide 3 of the first element (for the left eye) is the second waveguide for the second element (for the right eye), that is, it is the common second waveguide 3. The common second waveguide 3 with the input / output second diffraction grating 3a common for the left and right eyes on the common frame of glasses located above the left eye and above the right eye and combining the field of view for the left and right eye. In the embodiment (Fig. 7 b), each of the first element (for the left eye) and the second element (for the right eye) contains its own projection system 1 and the expanding first waveguide 2 with the expanding first diffraction grating, located on the side of the left and right eyes, respectively. It should be noted that in this embodiment, two projection systems 1 have one common driver for synchronizing their work, but in this embodiment it is not possible to provide a stereo image.

In one configuration of augmented reality glasses (FIG. 7 c), the first element (for the left eye) is also combined with the second element (for the right eye). The second waveguide 3 of the first element (for the left eye) is also the second waveguide for the second element (for the right eye), that is, it is a common second waveguide 3. A common second waveguide 3 with an input / output second diffraction grating 3a are located on a common frame of glasses, located above the left eye and above the right eye. In the embodiment (Fig. 7 c), the first element (for the left eye) and the second element (for the right eye) contain one projection system 1 and one expanding first waveguide 2 with an expanding first diffraction grating, located respectively on the side (from the temporal part) left or right eye, respectively.

Since the invention uses all significant diffraction orders - minus the first and first order for expansion, radiation loss does not occur. And due to the fact that the first and second diffraction gratings are located in different planes, and the radiation is output at the same angle at which it is introduced, the image that the eye sees is not limited by any of the coordinate axes, in addition, the image is bright and The field of eye movement is wider and more comfortable for the user.

As a projection system, any compact projector can be selected, for example, such as DMD projectors, LCoS projectors, SLM projectors, laser scanner projectors, etc.

Figures 8 a, b show how the expansion (propagation) of radiation occurs in the expanding first waveguide with the expanding first diffraction grating in the embodiment when the expanding first diffraction grating is made on the first surface of the expanding first waveguide onto which radiation from the projection system is incident. The expanding first waveguide 2, containing the expanding first diffraction grating 2a, as shown in FIGS. 8a and 8b, is located in the region of the exit pupil of the projection system 1. The expanding first waveguide 2 consists of a transparent waveguide, which can be made of any suitable material (for example, glass , plastic, crystalline material, etc.) by traditional methods, and by expanding the first diffraction grating on the first flat surface of the waveguide onto which radiation from the projection system is incident.

It should be noted that it is important how the strokes of the expanding first diffraction grating are located relative to the incident radiation. Figure 9 shows the necessary relative arrangement of the strokes of the expanding first diffraction grating and the incident radiation, in the case of such an arrangement, all diffraction orders will be useful. That is, a necessary condition for the expansion (reproduction) of radiation incident from the projection system to occur is the location of the strokes of the expanding second diffraction grating precisely along the direction of propagation of the center of the field of the projection system (not across). It is necessary to clarify that a specialist in the art knows such concepts as an angular field and a linear field, in this application we are talking about angular fields, as well as a specialist in the art understands the terms center of field and field edge. In other words, the strokes of the expanding first diffraction grating should be located along the projection of the incident radiation onto the diffraction grating. That is, the acute angle between the projection of the main beam of the projection system onto the plane of the first waveguide and the line of strokes should be in the range of ± 30 °.

Let us return to Figures 8a and 8b, getting from the projection system 1 onto the beam expanding the first diffraction grating 2a, as a result of diffraction, it is divided into several rays (diffraction orders) that propagate at certain angles relative to the incident one. Of these several rays, a zero order of "0" diffraction is distinguished, which does not change the direction of propagation relative to the incident one, and also minus the first diffraction order of "-1" and the first diffraction order of "+1". Minus the first diffraction order “-1” and the first diffraction order “+1” propagate symmetrically at angles relative to the incident beam. Zero diffraction order 6 passes through the waveguide and leaves the expanding first waveguide 2 without changing the direction with respect to the incident beam, and falls on the second diffraction grating 3a of the second waveguide 3. The minus first diffraction order “-1” and the first diffraction order “+1” remain in the expanding first waveguide, propagating in the expanding first waveguide, they fall on its opposite surface (on the surface opposite to the expanding first diffraction grating), experience total internal reflection (TIR) and the ova fall onto the expanding first diffraction grating 2a of the expanding first waveguide 2. Next, minus the first diffraction order “-1” and the first diffraction order “+1”, each experiences diffraction, as a result of which each one again forms its own “0” and “-1 "And" +1 "diffraction orders. Each “0” diffraction order leaves the expanding first waveguide and enters the second diffraction grating 3a of the second waveguide 3, and each of “-1” and “+1” propagate in the expanding first waveguide 2, as already described above, and produce new “0”, “-1” and “+1” diffraction orders, as a result of which the pupil 5 multiplies or multiplies (Figure 8a), relative to the radiation that has fallen into the expanding first waveguide 2.

After the rays of zero diffraction orders fall from the expanding first waveguide 2 onto the second waveguide 3, the rays of zero diffraction orders fall on the second diffraction grating 3a, made in the second waveguide 3, which faces the eye, and zero diffraction orders of zero “0” are formed, minus first "-1" and first "+1". Minus the first “-1” diffraction order extends away from the eye and becomes useless. Zero “0” diffraction order passes through the second waveguide and leaves the second waveguide in the same direction as the initial beam incident from the projection system. And only the “+1” diffraction order, propagating at an angle to the zero diffraction order, experiences complete internal reflection from the wall of the second waveguide, opposite the wall of the second waveguide facing the eye, remains in the second waveguide, re-enters the second diffraction grating from the inside of the second waveguide, it is also divided into "0", "+1", "-1" diffraction orders, and already this new "0" zero diffraction order leaves the second waveguide 3 towards the eye and enters the eye. And new plus first orders of “+1” diffraction propagate further along the waveguide, then everything repeats: air defense, diffraction, etc., and each zero diffraction order will fall into the eye, as described above. Since, due to the expansion of radiation described above, there are many emission exit points 5, and they are spaced apart in space, a field is formed in which the eye can move, that is, a field of eye movement in which the image does not disappear from the field of view of the eye. Thus, a wide field of eye movement is formed. Due to such a system for expanding radiation and using all diffraction orders, the proposed device minimizes radiation losses from the projection system in all directions.

If the expanding first diffraction grating is located on the first surface of the waveguide onto which radiation from the projection system is incident, the radiation from the projection system is incident on the expanding first diffraction grating, diffracts to the first, zero, and minus first diffraction orders and if the expanding first diffraction grating is located on the first side of the expanding first waveguide, onto which the radiation from the projection system is incident, then the zeroth diffraction order leaves the second side of the expanding first farmers and gets on the second diffraction grating. Moreover, if the second surface of the expanding first waveguide, opposite to the first surface of the expanding first waveguide, onto which the radiation from the projection system falls, has a mirror coating, and the expanding first diffraction grating is located on the first surface of the expanding first waveguide, then the zeroth order together with the first and minus first diffraction order hits the mirror surface, is reflected and leaves the first surface of the expanding first waveguide.

If the expanding first diffraction grating is located on the second surface of the waveguide, opposite the first surface onto which radiation from the projection system falls, the radiation from the projection system enters the waveguide, passes to the expanding first diffraction grating, diffracts by the first, zero, and minus first diffraction orders, zero the diffraction order leaves the second side of the expanding first waveguide and enters the second diffraction grating.

As noted above, for the effective expansion of radiation, the projection system must be located so that the angle at which the radiation from the projection system falls on the expanding first waveguide and falls on the expanding first diffraction grating should be in the range from 0 ° to 90 ° with respect to the normal to the surface of the expanding first waveguide (see Fig. 9), and all radiation must fall on the expanding first waveguide relative to the normal to the surface of the expanding first waveguide from the side opposite to the second waveguide, in other words, the cone of incoming rays should not go beyond the aforementioned it is normal for all incident radiation to expand symmetrically. Moreover, as mentioned above, the sharp angle between the projection of the main beam of the projection system onto the plane of the first waveguide and the line of strokes should be in the range of ± 30 °.

As mentioned above, one of the features of the invention is that the second diffraction grating deposited on the second waveguide is used both to introduce radiation incident from the expanding first waveguide, and to output radiation into the eye region. That is, the same direction of strokes of the diffraction grating is used both for introducing radiation into the second waveguide and for outputting radiation from the second waveguide into the eye region, due to the location of the expanding first waveguide with the expanding first diffraction grating and the second waveguide with the second diffraction grating in different planes.

For clarity, the advantages of the present invention, in comparison with the prior art, are schematically shown in figures 10a and 10b. Figure 10a shows an augmented reality device element typical of the prior art, and figure 10b shows an inventive device for displaying augmented reality. As can be seen from figure 10a from the projection system only a narrow region of radiation (a) enters the waveguide. After passing through the input diffraction grating, only one diffraction order enters the waveguide, and there is no intersection of different areas of the field of view in the area of radiation output to the eye. The extreme part of the field of view extends along the waveguide at an angle downward (b) and does not enter the pupil of the eye if the eye is looking at the central or upper part of the field of vision, only a narrow area of the output beams (c) of radiation from the central part of the field of vision enters the pupil if the eye looks at the central part of the field of view, as a result, only a narrow strip of the image is visible to the eye. On the contrary, as shown in figure 10b, when using the present invention, the radiation region (a) is expanded in the expanding first waveguide 2, the expanded radiation enters the second waveguide 3, and all the expanded radiation (b) and (c), intersecting, enters the pupil of the eye , providing a wide field of eye movement while maintaining the lower part of the image and the side parts of the image.

In solutions known from the prior art, when there are restrictions on the width of the field of view, the edges of the image are clear, because the total internal reflection is violated and the radiation responsible for the edges of the image does not go into the field of eye movement. In the proposed device, the user can see the entire image, and at the edges of the image, the brightness decreases.

Thanks to the invention, a large field of view, providing the user with a wide field of eye movement, gives an exciting sense of presence, for example, in a game or in a film. High resolution provides a realistic presence, the user can see all the details almost like in the real world. Watching a movie with glasses that use the proposed device to display augmented reality, the user will be completely immersed in the virtual world.

The present invention can be used in any AR / VR, HUD, HMD devices, where it is necessary to have a high-resolution image and a wide field of view.

In bright ambient lighting, including sunlight, in augmented reality glasses using the proposed device to display augmented reality, a bright and clear image will be provided.

Although the invention has been described in connection with some illustrative embodiments, it should be understood that the invention is not limited to these specific embodiments. On the contrary, it is assumed that the invention includes all alternatives, corrections and equivalents that may be included in the essence and scope of the claims.

In addition, the invention retains all equivalents of the claimed invention, even if the claims change during the review process.

Claims (40)

1. A method of displaying augmented reality, comprising stages in which: A) the radiation from the projection system falls on the expanding first diffraction grating; B) the diffraction of each of the rays incident on the expanding first diffraction grating forms minus the first diffraction order, the zero diffraction order and the first diffraction order; C) the zero diffraction order leaves the expanding first waveguide and enters the second waveguide; D) minus the first diffraction order and the first diffraction order propagate in the expanding first waveguide due to total internal reflection, return to the expanding first diffraction grating, hitting it at various points that do not coincide with each other, undergo diffraction again, each forming a new minus the first diffraction order, a new zero diffraction order, a new first diffraction order, E) for each new minus the first diffraction order, the new zero diffraction order, the new first diffraction order, steps (B) - (D) are repeated; E) each zero diffraction order incident on the second waveguide passes through the second waveguide to the second diffraction grating, and the diffraction of each of the rays incident on the second diffraction grating forms minus the first diffraction order, zero diffraction order and the first diffraction order, the first order diffraction experiences total internal reflection from the wall of the second waveguide, opposite to the wall of the second waveguide facing the eye, re-hits the second diffraction grating, forms a new minus the first th diffraction order, a new zero-order diffraction and the new first-order diffraction, wherein the said new zero diffraction order emerges from the waveguide in the direction of the eye. 2. A device for displaying augmented reality, the method according to claim 1, comprising: projection system; an expanding first waveguide, on the first surface of which rays from the projection system are incident, wherein the expanding first waveguide comprises an expanding first diffraction grating; a second waveguide comprising a second diffraction grating; moreover, the expanding first diffraction grating and the second diffraction grating are located in different planes relative to each other so that the zero diffraction order emerging from the expanding first waveguide falls on the second waveguide. 3. The device according to claim 2, in which the angle at which the rays from the projection system fall on the expanding first waveguide and fall on the expanding first diffraction grating, is in the range from 0 ° to 90 ° with respect to the normal to the surface of the expanding first waveguide. 4. The device according to claim 2, in which the strokes of the expanding first diffraction grating should be located along the projection onto the expanding first diffraction grating of rays from the projection system. 5. The device according to claim 2, in which the acute angle between the projection of the main beam of the projection system onto the plane of the first waveguide and the line of strokes is in the range of ± 30 °. 6. The device according to any one of paragraphs. 2-5, in which the expanding first diffraction grating is located on the second surface of the expanding first waveguide, opposite the first surface of the expanding first waveguide, onto which radiation from the projection system is incident. 7. The device according to claim 6, in which the expanding first diffraction grating is reflective. 8. The device according to any one of paragraphs. 2-5, in which the expanding first diffraction grating is located on the first surface of the expanding first waveguide. 9. The device of claim 8, in which the expanding first diffraction grating is transmission. 10. The device according to claim 8, in which the second surface of the expanding first waveguide, opposite to the first surface of the expanding first waveguide, onto which radiation from the projection system is incident, has a mirror coating. 11. The device according to any one of paragraphs. 2-5, in which the expanding first diffraction grating is located on the second surface of the expanding first waveguide, wherein the second surface of the expanding first waveguide is a reflective surface. 12. The device according to any one of paragraphs. 2-5, 7, 9, 10, in which the second waveguide includes a radiation input region, an intermediate region from which the output radiation does not enter the pupil of the eye, an effective radiation output region from which radiation can enter the pupil of the eye when the pupil is moved eyes while watching. 13. The device according to item 12, in which in the intermediate region of the second waveguide diffraction does not occur. 14. The device according to p. 12, in which in the second waveguide the radiation input region is made with high diffraction efficiency, the intermediate region is made with low diffraction efficiency, the useful radiation output region is made with low diffraction efficiency. 15. The device according to p. 12, in which in the second waveguide the input region of radiation is made with high diffraction efficiency, the intermediate region is made with average diffraction efficiency, the area of useful output of radiation is made with average diffraction efficiency. 16. The device according to p. 12, in which in the second waveguide the radiation input region is made with high diffraction efficiency, the intermediate region and the useful output region is made with gradient diffraction efficiency, that is, the low diffraction efficiency is gradually increasing. 17. The device according to p. 12, in which in the second waveguide the radiation input region is made with high diffraction efficiency, the intermediate region is made with low diffraction efficiency, the useful output region is made with gradient diffraction efficiency, that is, the low diffraction efficiency is gradually increasing. 18. The device according to any one of paragraphs. 2-5, 7, 9, 10, 13-17, in which the expanding first waveguide and the second waveguide together are made in the form of a monolithic curved waveguide. 19. The device according to any one of paragraphs. 2-5, 7, 9, 10, 13-17, in which the expanding first diffraction grating and the second diffraction gratings are diffractive optical elements. 20. The device according to any one of paragraphs. 2-5, 7, 9, 10, 13-17, in which the expanding first diffraction grating is an optical diffraction element, the second diffraction grating is a holographic element. 21. The device according to any one of paragraphs. 2-5, 7, 9, 10, 13-17, in which the expanding first diffraction grating is a holographic element, the second diffraction grating is an optical diffraction element. 22. The device according to any one of paragraphs. 2-5, 7, 9, 10, 13-17, in which the first and second diffraction gratings are holographic elements. 23. The device according to any one of paragraphs. 2-5, 7, 9, 10, 13-17, in which the boundary of the region of the expanding first waveguide, within which the expanding first diffraction grating is located, can be made in the form of a geometric figure, which is one of a rectangle, a polygon, or any geometric a figure with indirect arcuate sides and can be symmetric or asymmetric. 24. Glasses of augmented reality, containing an element for the left eye and an element for the right eye, each of the elements for the left and right eye is a device for displaying augmented reality according to any one of paragraphs. 2-23. 25. Glasses according to claim 24, in which the element for the left eye is located separately from the element for the right eye, the second waveguide of the element for the left eye is located on a separate left frame of glasses located above the left eye, and the second waveguide of the element for the right eye is located on a separate the right frame of the glasses, located above the right eye. 26. Glasses according to paragraph 24, in which the element for the left eye is combined with the element for the right eye, and the second waveguide of the element for the left eye is the second waveguide for the element for the right eye and is located on the common frame of the glasses located above the left eye and above right eye. 27. Glasses according to claim 24, in which the expanding first waveguide of each of the elements for the left and right eye is located on the side of the left and right eye, respectively. 28. Glasses according to claim 24, in which the projection system and the expanding first waveguide of the element for the left eye are the projection system and the expanding first waveguide for the element for the right eye, said projection system and the expanding first waveguide located to the side of the left or right eye.

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