CN115728942A - Optical system with augmented reality - Google Patents

Abstract

An optical system with augmented reality comprises a display screen for emitting light; and the light guide element comprises an incident surface and a plurality of reflecting surfaces, the incident surface is arranged at the top end of the light guide element and is adjacent to one emergent reflecting surface of the reflecting surfaces, the emergent reflecting surface is a surface opposite to one human eye, the display screen is arranged opposite to the incident surface so as to lead the light to enter the light guide element from the incident surface, and the light is led into the human eye from the emergent reflecting surface after being reflected for three times by the reflecting surfaces in the light guide element. The display screen is arranged above the light guide element, and the lens has the effects of correcting the diopter of eyes and enhancing the reality through two times of total reflection and one time of partial penetrating partial reflection, so that the thickness of the optical system is reduced, and the light and thin effect is achieved.

Description

Optical system with augmented reality

technical field

The invention relates to an optical structure, in particular to an optical system with augmented reality.

Background technique

Wearable devices are considered to be one of the electronic products with the greatest market growth potential after smartphones. Wearable devices can be classified into glasses type, watch type, wearing type, wearable type and attachment type according to different wearing types. The application of wearable devices combined with virtual reality (Virtual Reality, VR), mixed reality (Mixed Reality, MR) or augmented reality (Augmented Reality, AR) is gradually increasing. Taking augmented reality glasses as an example, how to make the lenses light and thin, so that the glasses can also have the effect of augmented reality without changing the shape of the frame and the weight of the glasses as much as possible, is an important issue in this field.

At present, most augmented reality glasses place the display screen on both sides of the lens, which is convenient for installing the display screen, but the distance from the light to the position where the human eye looks directly will increase, and a thicker lens is needed to achieve a good viewing angle. Aberration correction. In order to switch the transparent optical state of the lens (used by general glasses) and the augmented reality state (activate the display screen, emit image light), most of the current light is introduced into the human eye by means of diffraction or grating, but this will make the optical system More complicated and defeats the purpose of being thin and light.

Therefore, the present invention proposes an augmented reality optical system aiming at the above-mentioned deficiencies in the prior art and future demands. The specific architecture and its implementation will be described in detail below:

Contents of the invention

The main purpose of the present invention is to provide an optical system with augmented reality, which allows the lens to simultaneously correct the diopter of the eye and Augmented reality effect.

Another object of the present invention is to provide an augmented reality optical system, which arranges the display screen above the light guide element, shortens the distance from the incident surface to the second reflective surface, so as to achieve the effect of thinning the lens.

In order to achieve the above purpose, the present invention provides an optical system with augmented reality, comprising: a display screen emitting light; The top is adjacent to one of the reflective surfaces, the outgoing reflective surface, wherein the outgoing reflective surface is the surface opposite to a human eye, and the incident surface is set corresponding to the display screen, so that light enters the light guide element from the incident surface, and the light guide element After being reflected three times by the reflective surface, the light is guided into human eyes from the outgoing reflective surface.

According to an embodiment of the present invention, the incident surface is an inclined surface.

According to an embodiment of the present invention, the reflective surface further includes a first reflective surface and a second reflective surface, the first reflective surface is disposed opposite to the outgoing reflective surface, wherein the outgoing reflective surface is a surface close to the human eye, and the first reflective surface is The surface away from human eyes, the second reflective surface is arranged at the bottom of the light guide element.

According to the embodiment of the present invention, after the light passes through the incident surface, it is reflected by the first reflective surface, the outgoing reflective surface and the second reflective surface in sequence, and then guides into human eyes.

According to an embodiment of the present invention, the upper half of the outgoing reflective surface is used to reflect the light reflected by the first reflective surface to the second reflective surface, and the light reflected by the second reflective surface is emitted from the lower half of the outgoing reflective surface light guide element.

According to the embodiment of the present invention, the light is totally reflected by the first reflective surface to the outgoing reflective surface, and the outgoing reflective surface totally reflects the light totally reflected by the first reflective surface again.

According to an embodiment of the present invention, the second reflective surface is provided with a partially penetrating and partially reflective coating, and the light reflected from the outgoing reflective surface is partially penetrating and partially reflected through the second reflective surface, wherein the light partially reflected by the second reflective surface The light will pass through the exit reflective surface to reach the human eye.

According to an embodiment of the present invention, the second reflective surface is an inclined surface.

According to an embodiment of the present invention, the first reflective surface and the outgoing reflective surface are axisymmetric curved surfaces, and the symmetry axes of the first reflective surface and the outgoing reflective surface are arranged coaxially.

According to an embodiment of the present invention, the incident surface and the reflective surface are one of spherical, aspheric or flat.

其中C为曲率半径的倒数。According to an embodiment of the present invention, when the incident surface and the reflecting surface are spherical,

where C is the reciprocal of the radius of curvature.

其中A、B、C、D、E等为非球面公式中的参数，C为曲率半径的倒数，K为圆锥系数。According to an embodiment of the present invention, when the incident surface and the reflecting surface are aspherical,

Among them, A, B, C, D, E, etc. are the parameters in the aspheric formula, C is the reciprocal of the radius of curvature, and K is the conic coefficient.

According to an embodiment of the present invention, when the incident plane and the reflecting plane are planes, Z=0.

According to the embodiment of the present invention, the combination of the curvature of the first reflective surface and the outgoing reflective surface makes the light guide element have a diopter, and the range of the diopter is between plus and minus 8 degrees.

According to the embodiment of the present invention, the included angle between the display screen and a Y axis is θ _p , the incident angle of light incident on the first reflective surface from the center of the display screen is θ _S1 , and the optical system conforms to

According to an embodiment of the present invention, the refractive index of the light guide element is n ₁ , the radius of curvature of the first reflective surface is R _S1 , the radius of curvature of the outgoing reflective surface is R _S2 , and the optical system conforms to

According to the embodiment of the present invention, the height of light incident on the first reflective surface at the center of the display screen is H _S1 , the curvature radius of the first reflective surface is R _S1 , and the optical system conforms to

According to an embodiment of the present invention, the light guide element and an auxiliary lens are combined into a lens, and the second reflective surface is adjacent to the auxiliary lens.

According to an embodiment of the present invention, the shape of the lens conforms to the frame of an augmented reality glasses.

Description of drawings

1 and 2 are perspective views of a lens with an augmented reality optical system according to the present invention.

3 and 4 are schematic diagrams of optical paths and angles of the optical system with augmented reality of the present invention.

FIG. 5 is a schematic diagram of the application of the augmented reality optical system in glasses according to the present invention.

6 and 7 are schematic diagrams of wearing the glasses of FIG. 5 on a human face.

8 to 11 are schematic diagrams of other embodiments of the optical system with augmented reality of the present invention.

List of reference signs: 10—optical system with augmented reality; 12—display screen; 14—mirror; 142—light guide element; 144—auxiliary lens; 168-the second reflective surface; 18-human eyes; 20-frame.

Detailed ways

The present invention provides an optical system with augmented reality, which can be applied to myopia glasses, plano glasses or hyperopia glasses, so that these three kinds of glasses can have the effect of augmented reality, making it convenient for users to wear them. In addition, through the design of setting the display screen above the lens, the thickness of the light guide element can still achieve the effect of augmented reality, making the overall optical system thinner and lighter.

Please refer to Fig. 1, Fig. 2, Fig. 3 and Fig. 4 at the same time, wherein Fig. 1 and Fig. 2 are perspective views of lenses 14 of the optical system 10 with augmented reality of the present invention, Fig. 3 and Fig. 4 are optical systems with augmented reality of the present invention Schematic diagram of the optical paths and angles of the system 10. The optical system 10 with augmented reality of the present invention includes a display screen 12 and a light guide element 142, wherein the display screen 12 is used to emit light, especially image light including images; the light guide element 142 is sheet-shaped, including an incident Surface 162 and a plurality of reflective surfaces, the incident surface 162 is arranged on the top of the light guide element 142, the display screen 12 is arranged opposite to the incident surface 162, emits light from the top of the incident surface 162, and the light enters the light guide element from the incident surface 162 downwards 142. After being reflected three times in the light guide element 142 , the light is guided into the human eye 18 by the light guide element 142 .

More specifically, the incident surface 162 is an inclined surface, and the display screen 12 is parallel to the incident surface 162 . The reflective surface includes a first reflective surface 164 , an outgoing reflective surface 166 and a second reflective surface 168 . Wherein, the first reflective surface 164 is opposite to the outgoing reflective surface 166 , the outgoing reflective surface 166 is a surface close to the human eye 18 , and the first reflective surface 164 is a surface away from the human eye 18 . The incident surface 162 is adjacent to the first reflective surface 164 and the outgoing reflective surface 166 . Furthermore, the first reflective surface 164 and the outgoing reflective surface 166 are axisymmetric curved surfaces, and the symmetry axes of the first reflective surface 164 and the outgoing reflective surface 166 are arranged coaxially. The outgoing reflective surface 166 is divided into two parts, the upper half is the reflective surface, and the lower half is the outgoing surface. The second reflective surface 168 is disposed at the bottom of the light guide element 142 and is an inclined surface. After passing through the incident surface 162 , the light is reflected by the first reflective surface 164 , the outgoing reflective surface 166 , and the second reflective surface 168 in sequence, and then enters the human eye 18 .

The reason why the present invention provides three reflective surfaces is that if there are only two reflections, the thickness of the light guide element 142 needs to be thicker to achieve good aberration correction. If it is reflected three times, the light guide element 142 can be thinner to achieve a good aberration correction effect.

The second reflective surface 168 is provided with a partly penetrating and partially reflective coating (not shown in the figure), so the second reflective surface 168 has the effect of partially penetrating and partially reflecting. When the display screen 12 emits light, the light reaching the second reflective surface 168 will partly pass through the second reflective surface 168 and be directed forward, while part of the light will be reflected toward the human eye 18 . When the display screen 12 is not activated, the human eyes 18 can directly see external images through the first reflective surface 164 or the second reflective surface 168 .

The detailed path of the light is as follows: after the light passes through the incident surface 162 , it is totally reflected by the first reflective surface 164 to the upper half of the outgoing reflective surface 166 . Since the upper half of the outgoing reflective surface 166 is a reflective surface, the light totally reflected by the first reflective surface 164 will be totally reflected again by the upper half of the outgoing reflective surface 166 and reflected to the second reflective surface 168 . When the light reflected by the upper half of the outgoing reflective surface 166 passes through the second reflective surface 168, it will partially penetrate and partially reflect, wherein the light partially reflected by the second reflective surface 168 will pass through the lower part of the outgoing reflective surface 166. The half part reaches the human eye 18, so that the human eye 18 can see the image displayed on the display screen 12 and see the external image at the same time, so as to achieve the purpose of augmented reality.

The light guide element 142 and an auxiliary lens 144 are combined into a lens 14 , the second reflective surface 168 at the bottom of the light guide element 142 is adjacent to the auxiliary lens 144 , and combined with the bottom of the light guide element 142 by bonding, bonding or other means. The purpose of providing the auxiliary lens 144 is to make the shape of the lens 14 conform to the frame of an augmented reality glasses. And because the user can also see external images through the auxiliary lens 144 , therefore, the auxiliary lens 144 will be consistent with the light guide element 142 in terms of material selection. Because if the materials of the auxiliary lens 144 and the light guide element 142 are inconsistent, the refractive index is also different, and the user sees the external scene through the lens, and the scene will be discontinuous due to the difference in the optical path difference of the lens. The user can directly wear the glasses including the augmented reality optical system 10 of the present invention without switching between the original myopia glasses or hyperopia glasses and the augmented reality glasses.

其中C为曲率半径的倒数。当入射面162、第一反射面164、出射反射面166及第二反射面168为非球面时，具增强现实的光学系统10符合公式

其中A、B、C、D、E等为非球面公式中的参数，C为曲率半径的倒数，K为圆锥系数。当入射面162、第一反射面164、出射反射面166及第二反射面168为平面时，具增强现实的光学系统10符合公式Z＝0。In the present invention, the incident surface 162 , the first reflective surface 164 , the outgoing reflective surface 166 and the second reflective surface 168 are one of a spherical surface, an aspherical surface or a plane. When the incident surface 162, the first reflective surface 164, the outgoing reflective surface 166 and the second reflective surface 168 are spherical, the optical system 10 with augmented reality satisfies the formula

where C is the reciprocal of the radius of curvature. When the incident surface 162, the first reflective surface 164, the outgoing reflective surface 166 and the second reflective surface 168 are aspherical, the optical system 10 with augmented reality satisfies the formula

Among them, A, B, C, D, E, etc. are the parameters in the aspheric formula, C is the reciprocal of the radius of curvature, and K is the conic coefficient. When the incident surface 162 , the first reflective surface 164 , the outgoing reflective surface 166 and the second reflective surface 168 are planes, the optical system 10 with augmented reality conforms to the formula Z=0.

In the present invention, in order to enable the human eye 18 to see the external image through the light guide element 142, that is, the external light will first pass through the first reflective surface 164 and then pass through the outgoing reflective surface 166 to reach the human eye 18, thereby enabling an augmented reality optical system 10's glasses have the effect of augmented reality glasses and myopia, farsightedness or plano glasses. Therefore, by utilizing the curvature matching between the first reflective surface 164 and the outgoing reflective surface 166 , the light guide element 142 has a diopter, and the range of the diopter is between plus and minus 8 degrees.

可达到良好的像差畸变修正。In addition, since the display screen 12 is inclined, it is also necessary to define the inclination angle of the display screen 12 and the included angle between the incident on the first reflective surface 164 . Assuming that the angle between the display screen 12 and the Y-axis is θ _p , and the incident angle of light incident on the first reflective surface 164 from the center of the display screen 12 is θ _S1 , the optical system 10 with augmented reality complies with

Good aberration distortion correction can be achieved.

可达到良好的屈光度矫正。In addition, since the light is refracted and reflected inside the light guide element 142 , it is necessary to define the relationship between the refractive index of the light guide element 142 and the curvature radii of the first reflective surface 164 and the outgoing reflective surface 166 . Assuming that the refractive index of the light guiding element 142 is n ₁ , the radius of curvature of the first reflective surface 164 is R _S1 , and the radius of curvature of the outgoing reflective surface 166 is R _S2 , the optical system 10 with augmented reality complies with

Good diopter correction can be achieved.

时，为可达到较大视角及轻薄化的较佳范围。Furthermore, the distance (height) between the first surface that the light touches after entering the light guide element 142, that is, the position that touches the first reflective surface 164, and the human eye 18 is also an important parameter, which represents the height of the light guide element. Whether the longitudinal length of 142 is short enough, can not exceed the longitudinal length of general spectacle lens. To adjust the height H _S1 of the light incident on the first reflective surface 164 at the center of the display screen 12 , it is also necessary to adjust the radius of curvature of the first reflective surface to R _S1 . In the present invention, when the optical system 10 with augmented reality conforms to

, it is a better range that can achieve a larger viewing angle and thinner.

FIG. 5 is a schematic diagram of the application of the augmented reality optical system in glasses according to the present invention. As shown in the figure, the lens 14 is a combination of the light guide element 142 and the auxiliary lens 144 , and the combined size conforms to the size of the frame 20 . The left and right sides of the mirror frame 20 are respectively provided with a display screen 12 . Wear the glasses shown in FIG. 5 on the human face, as shown in FIG. 6 and FIG. 7 . When the user wears the glasses, if the display screen 12 is not activated, they can generally be used as plain glasses, nearsighted glasses or farsighted glasses. When the display screen 12 emits image light, the user can see the augmented reality image.

8 to 11 are different embodiments of the lens 14, wherein FIG. 8 is the first embodiment, and the lens 14 is a lens of plano glasses. Fig. 9 is a second embodiment, and its lens 14 is also a lens of plano glasses. Fig. 10 is the third embodiment, and its eyeglass 14 is the eyeglass of the myopic glasses of-2.25 degree. Fig. 11 is the fourth embodiment, and its eyeglass 14 is the eyeglass of the hyperopic glasses of +2.75 degree. The parameters of each embodiment are shown in Table 1, and the optimal values of the corresponding formulas are shown in Table 2:

parameter first embodiment second embodiment third embodiment Fourth embodiment 1 θ_p 48.6° 55.0° 53.2° 30.44° 2 θ_S1 54.2° 57.45° 55.4° 48.8° 3 n₁ 1.543 1.543 1.543 1.543 4 R_S1 -200 unlimited -400 -65 4 R_S2 -200 unlimited -151 -98 6 H_S1 20.55 20.64 19.65 20.6

Table I

Table II

To sum up, the optical system with augmented reality provided by the present invention can be applied to myopia glasses, plain vision glasses or hyperopia glasses, so that these three kinds of glasses can also have the effect of augmented reality, making it easy for users to wear them. In addition, because the general display screen is longer horizontally and shorter vertically, the design of the present invention arranges the display screen above the lens, shortens the height of the light guide element, makes the height and thickness of the light guide element light and thin, and can still achieve the effect of augmented reality , making augmented reality glasses thinner and lighter. Furthermore, the optical system does not have any diffraction or interference elements or free-form surfaces, and only uses aspheric surfaces, spherical surfaces or flat surfaces. Therefore, the structure is simple and can achieve good aberration correction, and the manufacturability is high. In terms of functionality, the augmented reality glasses using the optical system of the present invention can meet the requirements of refractive correction at the same time.

The above-mentioned ones are only preferred embodiments of the present invention, and are not intended to limit the implementation scope of the present invention. Therefore, all equivalent changes or modifications based on the features and spirit described in the scope of the application of the present invention shall be included in the scope of the patent application of the present invention.

Claims (19)

1. An optical system with augmented reality, comprising:

a display screen for emitting light; and

the light guide element comprises an incident surface and a plurality of reflecting surfaces, wherein the incident surface is arranged at the top end of the light guide element and is adjacent to one emergent reflecting surface of the plurality of reflecting surfaces, the emergent reflecting surface is a surface opposite to one eye of a person, the incident surface is arranged corresponding to the display screen so as to enable the light to enter the light guide element from the incident surface, and after the light is reflected for three times by the plurality of reflecting surfaces in the light guide element, the light is guided into the eye of the person from the emergent reflecting surface.

2. The optical system of claim 1, wherein the incident surface is an inclined surface.

3. The optical system of claim 1, wherein the plurality of reflective surfaces further includes a first reflective surface and a second reflective surface, the first reflective surface is disposed opposite to the exit reflective surface, the exit reflective surface is a surface close to the human eye, the first reflective surface is a surface far away from the human eye, and the second reflective surface is disposed at a bottom of the light guide element.

4. The optical system of claim 3, wherein the light beam is guided to the human eye after passing through the incident surface and being reflected by the first reflecting surface, the exit reflecting surface and the second reflecting surface in sequence.

5. The optical system of claim 4, wherein the upper half of the exit reflective surface is used to reflect the light reflected by the first reflective surface to the second reflective surface, and the light reflected by the second reflective surface exits the light guide element from the lower half of the exit reflective surface.

6. The optical system of claim 3, wherein the light beam is totally reflected by the first reflecting surface to the exit reflecting surface, and the exit reflecting surface totally reflects the light beam totally reflected by the first reflecting surface again.

7. The optical system of claim 4, wherein the second reflective surface is provided with a partially transmissive and partially reflective coating, and the light reflected by the exit reflective surface is partially transmissive and partially reflective via the second reflective surface, wherein the light partially reflected by the second reflective surface passes through the exit reflective surface to reach human eyes.

8. The optical system of claim 3, wherein the second reflecting surface is an inclined surface.

9. The optical system of claim 3, wherein the first reflective surface and the exit reflective surface are axisymmetric curved surfaces, and the symmetry axes of the first reflective surface and the exit reflective surface are coaxially disposed.

10. The optical system of claim 1, wherein the incident surface and the reflective surfaces are one of spherical, aspherical, or planar.

11. The optical system of claim 10, wherein the incident surface and the plurality of reflecting surfaces are spherical surfaces,

where C is the inverse of the radius of curvature.

12. The optical system of claim 10, wherein when the incident surface and the reflective surfaces are aspheric,

a, B, C, D, E is the parameter in the aspheric surface formula, C is the reciprocal of the curvature radius, and K is the conic coefficient.

13. The optical system of claim 10, wherein Z =0 when the incident surface and the plurality of reflecting surfaces are planar.

14. The optical system of claim 3, wherein the curvature of the first reflective surface and the curvature of the exit reflective surface are matched to provide a diopter for the light guide element, wherein the diopter ranges between plus or minus 8 degrees.

15. The optical system of claim 3, wherein the display screen is disposed at an angle θ to a Y-axis _p The incident angle of the light incident on the first reflecting surface from the center of the display screen is theta _S1 The optical system is in accordance with

16. The optical system of claim 3, wherein the refractive index of the light guide element is n ₁ The radius of curvature of the first reflecting surface is R _S1 The radius of curvature of the exit reflecting surface is R _S2 The optical system is in accordance with

17. The optical system of claim 3, wherein the height of the light incident on the first reflecting surface from the center of the display screen is H _S1 The radius of curvature of the first reflecting surface is R _S1 The optical system is in accordance with

18. The optical system of claim 3, wherein the light guide element and an auxiliary lens are combined into a lens, and the second reflective surface is adjacent to the auxiliary lens.

19. The optical system of claim 18, wherein the shape of the lens conforms to a frame of an augmented reality glasses.

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