A portable short focal near-eye display system

Abstract

The utility model provides a kind of portable short-focus near-eye display system, it is related to near-eye display technical field, solve the contradiction between optical performance and volume in existing AR technology, the system includes micro display, inner side lens and concave partial mirror;It is inner side lens close to eye pupil position, and it is concave partial mirror far from eye pupil position;Micro display is rotating linear display or transparent display.Light path is folded by multiple reflections, the distance between convex part mirror and concave partial mirror is shortened, the thickness of glasses can be reduced to maximum amplitude, and thinness is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of near-eye display, in particular to a light and short-focus near-eye display system. BACKGROUND

[0002] Near-eye display can provide users with a huge 3D picture, and the displayed image can be integrated with the real environment, which has very wide application in daily life and industrial field.

[0003] At present, the most promising is the optical waveguide AR glasses, which can realize the appearance similar to ordinary glasses, but due to the constraints of refractive index, diffraction efficiency, etc., the field of view angle is difficult to break through, generally about 50° on the diagonal, and the biggest disadvantage is that the ultra-low energy efficiency will cause the whole system to consume a lot of power. The present application solves the above problems by using spherical symmetry. Based on the spherical symmetry technology, the series of patent technologies (patent number: 202020742439, 202120312789.X, 202110154039) previously applied by the inventor have achieved very ideal optical effects, but the total thickness is large, and the present application further reduces the thickness of the system. By making the light reflect between the two spherical surfaces multiple times, the thickness is further reduced, the exit pupil distance is increased, and the thinness is realized. At the same time, the present application proposes a new type of linear display structure, which can realize unobstructed display, and further improves the use effect. Thirdly, due to the use of multiple reflections, the mutual position between the lenses is more sensitive, the moving amount of zoom is reduced, and the zoom function is easy to realize. SUMMARY

[0004] The present application provides a light and short-focus near-eye display system to solve the problem of large thickness of the existing display system near-eye display system, which cannot realize thinness.

[0005] A light and short-focus near-eye display system, comprising a micro display, an inner lens and a concave partial reflector; the inner lens is close to the eye pupil position, and the concave partial reflector is placed away from the eye pupil position, the micro display is a rotating linear array micro display or a transparent micro display, and the inner lens is a convex reflector;

[0006] The micro display is arranged between the inner lens and the eye pupil position, or between the inner lens and the concave partial reflector, or on the convex side of the concave partial reflector;

[0007] When the micro display is arranged between the inner lens and the eye pupil position, the micro display emits light away from the eye pupil position, and the number of reflections of the light emitted by the micro display between the inner lens and the concave partial reflector is greater than or equal to 3;

[0008] The micro display is arranged between the inner lens and the concave partial mirror, and the micro display emits light away from or towards the eye pupil position, and the light emitted by the micro display is reflected between the inner lens and the concave partial mirror for more than or equal to three times.

[0009] The micro display is arranged on the convex side of the concave partial mirror, and the micro display emits light towards the eye pupil position, and the light emitted by the micro display is reflected between the inner lens and the concave partial mirror for more than or equal to four times.

[0010] Further, the concave or convex surface of the inner lens is arranged as a polarized reflection surface, a phase retardation plate is arranged between the inner lens and the concave partial mirror, and an ambient light circular polarizer is arranged on the convex side of the concave partial mirror, which is used to change the natural ambient light into first circular polarized ambient light, and the first circular polarized ambient light becomes s-type linear polarized ambient light after passing through the phase retardation plate and enters the human eye.

[0011] Further, the light emitted by the micro display is reflected between the inner lens and the concave partial mirror for three times, the concave or convex surface of the inner lens is arranged as a polarized reflection surface, and a phase retardation wave plate is arranged between the micro display and the inner lens when the micro display is arranged between the inner lens and the concave partial mirror.

[0012] When the micro display is arranged between the inner lens and the eye pupil position, a phase retardation wave plate is arranged between the inner lens and the concave partial mirror.

[0013] Further, the linear array display includes light emitting pixels, transparent wires and a display driving chip, the transparent wires are connected to the light emitting pixels and the display driving chip, and the distance between the light emitting pixels and the display driving chip is greater than 1 mm.

[0014] The light emitting pixels are arranged in one row, 1 / 2 row, two rows in cross shape or four rows in rice grain shape.

[0015] Further, the two side regions of the light emitting pixels are arranged as transparent regions, partial reflection surfaces or polarized reflection surfaces; when the two side regions are partial reflection surfaces, the concave partial mirror is replaced; and when the two side regions are polarized reflection surfaces, the inner lens is replaced.

[0016] The light emitted by the micro display is reflected between the inner lens and the concave partial mirror for three times, the concave partial mirror is arranged as a strip-shaped partial mirror, the strip-shaped partial mirror is synchronously rotated with the linear array micro display, and an outer protective lens is arranged on one side of the strip-shaped partial mirror.

[0017] Further, the light emitted by the micro display is reflected between the inner lens and the concave partial mirror for 4 times, the inner lens is provided with a polarized reflection surface, the inner lens is provided with a strip shape in line with the pixel arrangement direction of the linear array micro display, and the concave partial mirror is provided with a strip shape partial mirror, and the inner lens, the strip shape partial mirror and the linear array micro display are synchronously rotated.

[0018] A strip shape central total reflection film is coated on the center of the inner lens, and the width of the central total reflection film is smaller than the pupil diameter of the human eye.

[0019] A phase delay wave plate is arranged between the inner lens and the concave partial mirror, and a polarized film layer is arranged in front of the light emitting pixel of the linear array micro display.

[0020] Further, two side areas of the light emitting pixel of the linear array micro display are provided with a partial reflection surface, instead of the strip shape partial mirror, the linear array micro display is synchronously rotated with the inner lens, an inner protection lens is arranged on the left side of the inner lens, and an outer protection lens is arranged on the side far from the eye pupil of the linear array micro display, and a rotating shaft is arranged on the inner protection lens and the outer protection lens.

[0021] Further, when the light emitted by the micro display is reflected between the inner lens and the concave partial mirror for more than 4 times, one surface of the inner lens is provided with a polarized reflection surface, a phase delay wave plate is arranged between the inner lens and the concave partial mirror, the partial reflection surface of the concave partial mirror is provided with a surface capable of dynamically adjusting the circular polarization reflection direction, the micro display emits pulsed circular polarization light, the concave partial mirror is provided with a state of keeping the reflected circular polarization direction unchanged, when the reflection times reach the designed times, the partial reflection surface of the concave partial mirror is provided with an ordinary mirror surface, and the light is reflected by the ordinary mirror surface and then enters the human eye.

[0022] Further, when the light emitted by the micro display is reflected between the inner lens and the concave partial mirror for more than 4 times, one surface of the inner lens is provided with a switch mirror surface, the micro display emits pulsed light, the switch mirror surface reflects the light when the reflection times do not reach the designed times, and the switch mirror surface becomes a transmission state when the reflection times reach the designed times, and the light is transmitted into the human eye.

[0023] Further, the inner lens and the concave partial mirror are combined into an integrated lens, the micro display is arranged to emit light to one side of the integrated lens, and the inner surface of the integrated lens is provided with a switch mirror surface.

[0024] The light emitted by the micro display is reflected between the inner surface of the integrated lens and the outer surface of the integrated lens, and the light is transmitted into the human eye after the reflection times reach the designed times.

[0025] The beneficial effects of the present application are:

[0026] The display system, the inner lens and the concave partial mirror have three times of reflection, the light path is folded, the lens thickness is thinned, the system is more compact, the exit pupil distance is further increased, the phase delay wave plate and the reflective polarizer are added to realize high energy efficiency display, the reflection is four times, the thickness is further reduced, the size of the micro display is increased, and the micro display is easy to manufacture.

[0027] The portable short focal near-eye display system provided by the present application can shorten the overall thickness of the glasses, increase the exit pupil distance, and make the user wear more comfortable and more beautiful through multiple reflection and folding of the light path.

[0028] The present application can reduce the light energy loss caused by the center blockage by special design of the linear array micro display, and can eliminate the blockage problem of the center axis by using a transparent rotating shaft.

[0029] By synchronously rotating the linear array display and the strip-shaped concave mirror, the transmittance of ambient light can be greatly improved, and the ambient brightness can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The light path diagram of the portable short focal near-eye display system with three reflections and the micro display on the right side of the inner lens is provided.

[0031] Figure 2 Unlike Figure 1 The light path diagram of another portable short focal near-eye display system with three reflections and the micro display on the left side of the inner lens is provided.

[0032] Figure 3 The light path diagram of the portable short focal near-eye display system with three reflections and the micro display on the right side of the inner lens is provided.

[0033] Figure 4 The light path diagram of the portable short focal near-eye display system with three reflections and the micro display on the left side of the inner lens is provided.

[0034] Figure 5 The schematic diagram of the present application is provided by adding circular polarization outside the concave partial mirror to eliminate ambient stray light.

[0035] Figure 6A structure diagram of a linear array micro display according to the present application; (a) is a schematic diagram of the linear array micro display in the yx plane with lower part mirror symmetry; (b) is a schematic diagram of the linear array micro display in the yx plane with lower part symmetry;

[0036] Figure 7 A structure diagram of a cross-shaped linear array display according to the present application;

[0037] Figure 8 A cross-sectional schematic diagram of the linear array micro display in the xz plane;

[0038] Figure 9 A light path and mounting structure diagram of the linear array micro display without a reflective film layer on both sides;

[0039] Figure 10 A light path and mounting structure diagram of the linear array micro display with a reflective film layer;

[0040] Figure 11 A light path and structure diagram of the linear array micro display and the strip-shaped concave mirror synchronously rotating;

[0041] Figure 12 A three-dimensional structure diagram of the linear array micro display and the strip-shaped concave mirror synchronously rotating;

[0042] Figure 13 A light path diagram of a portable short-focus near-eye display system with four reflections according to the present application, and the micro display is on the right side of the concave partial mirror;

[0043] Figure 14 A light path diagram of a portable short-focus near-eye display system with four reflections according to the present application, and the micro display is on the left side of the concave partial mirror;

[0044] Figure 15 A principle diagram of a portable short-focus near-eye display system with four reflections according to the present application, and the micro display is on the left side of the concave partial mirror;

[0045] Figure 16 A light path assembly diagram of a portable short-focus near-eye display system with four reflections according to the present application; (a) is a light path and assembly schematic diagram of the micro display on the left side of the concave partial mirror, (b) is a cross-sectional schematic diagram of the linear array micro display in the xz plane;

[0046] Figure 17 A light path polarization change schematic diagram of a portable short-focus near-eye display system with more than four reflections according to the present application, and the micro display is on the left side of the concave partial mirror; (a) is a light path diagram of a portable short-focus near-eye display system with more than four reflections according to the present application, and the micro display is on the left side of the concave partial mirror; (b) is a partial enlarged view of the light path among the inner lens, the concave partial mirror, and the micro display;

[0047] Figure 18A light path diagram of a portable short focal length near-eye display system with more than 4 reflections according to the present application;

[0048] Figure 19 A light path diagram of a portable short focal length near-eye display system with more than 4 reflections according to the present application, using an integrated lens and a micro display placed on the left side of the integrated lens; (a) is a schematic diagram of the micro display placed on the left side of the integrated lens; (b) is a partial enlarged view of the light path.

[0049] Figure 20 A light path diagram of a portable short focal length near-eye display system with more than 4 reflections according to the present application, using an integrated lens and a micro display placed on the right side of the integrated lens; (a) is a schematic diagram of the micro display placed on the right side of the integrated lens; (b) is a partial enlarged view of the light path.

[0050] In the figure: 1, eye pupil position, 2, inner lens, 2-1, concave surface, 2-2, convex surface, 2-3, inner lens extension end, 2-4, rotation shaft, 3, concave partial mirror, 3-1, inner surface, 3-2, outer surface, 3a, strip-shaped partial mirror, 4, micro display, 4a, linear array micro display, 4b, transparent micro display, 4a-1, linear array micro display light emitting pixel, 4a-2, transparent wire, 4a-3, linear array display driving chip, 4a-4, area on both sides of the light emitting pixel, 4a-5, front film layer of the light emitting pixel, 4a-6, linear array micro display extension end, 4a-7, inner magnetic ring of the linear array micro display, 4a-8, rotating concave ring, 5, ambient light, 5-1, natural ambient light, 5-2, s-type linear polarized ambient light, 5-3, first circular polarized ambient light, 6, phase delay wave plate, 7, light, 7-1, s-type linear polarized light, 7-2, p-type linear polarized light, 7-3, first circular polarized light, 7-4, second circular polarized light, 7-5, non-limited polarized light, 8, binding magnetic ring, 9, supplementary function board, 10, inner protective lens, 10-1, inner protective lens rotation shaft, 10-2, inner protective lens extension end, 11, outer protective lens, 11-1, outer protective lens rotation shaft, 12, frame, 13, center total reflection film, 14, integrated lens, 14-1, inner surface of the integrated lens, 14-2, outer surface of the integrated lens, 15, ambient light circular polarizer. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0052] It should be noted that when a component is referred to as being "connected" with another component, it can be directly connected with the other component or there can be intervening components present; when a component is referred to as being "fixed" with another component, it can be directly fixed with the other component or there can be intervening components present. "Left side" refers to the side facing the eye pupil position, and "right side" refers to the side facing away from the eye pupil towards the environment.

[0053] Unless otherwise defined, all technical and scientific terms used in the present embodiments have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application.

[0054] In combination Figures 1 to 11 In the present embodiment, an ultra-thin short-focus near-eye display optical system includes a micro display 4, an inner lens 2, and a concave partial mirror 3. The micro display 4 is located on the left side of the inner lens 2 or between the inner lens 2 and the concave partial mirror 3. The inner lens 2 is close to the eye pupil position 1, and the concave partial mirror 3 is placed away from the eye pupil position 1. The inner lens 2 is a convex mirror.

[0055] In combination Figure 1 When the micro display 4 is located between the inner lens 2 and the concave partial mirror 3, the micro display 4 emits light away from the eye pupil position 1. The light emitted by the micro display is reflected three times between the inner lens 2 and the concave partial mirror 3.

[0056] The light emitted by the micro display 4 is reflected by the concave partial mirror 3. Since the micro display 4 is a linear array or transparent, part of the reflected light can pass through the micro display 4 to reach the inner lens 2. The concave surface 2-1 or convex surface 2-2 of the inner lens 2 has a certain reflectivity, which can reflect the light. The reflected light passes through the micro display 4 again and reaches the concave partial mirror 3. The concave partial mirror 3 reflects the light again, and the reflected light passes through the inner lens 2 to reach the human eye.

[0057] In combination Figure 2 When the micro display 4 is located on the left side (concave surface 2-1) of the inner lens 2, the micro display 4 emits light away from the eye pupil position 1. The light is reflected three times between the inner lens 2 and the concave partial mirror 3.

[0058] The light emitted by the micro display first passes through the inner lens 2, and then is reflected by the concave partial mirror 3. The reflected light reaches the inner lens 2 again. The concave surface 2-1 or convex surface 2-2 of the inner lens 2 has a certain reflectivity, which can reflect the light. The reflected light reaches the concave partial mirror 3, which reflects the light again. The reflected light passes through the inner lens 2 and the micro display 4 to reach the human eye.

[0059] In this embodiment, the micro display 4 is a rotating linear array micro display 4a or a transparent micro display 4b; the transparent micro display 4b has pixels distributed on a spherical surface. The inner lens 2 is close to the eye pupil position 1, and the concave partial mirror 3 is away from the eye pupil position 1; one of the surfaces of the concave partial mirror 3, i.e. the inner surface 3-1 or the outer surface 3-2, has a certain reflectivity, such as 50%, and a certain transmittance, such as 50%, and for a certain wavelength, such as the visible light range, the sum of the transmittance and the reflectivity is close to or equal to 1.

[0060] In combination Figure 3 And Figure 4 In this embodiment, due to the back and forth folding of the light, the light energy is continuously lost, and there is a certain stray light. In order to optimize this problem, one of the surfaces of the inner lens 2, i.e. the concave surface 2-1 or the convex surface 2-2, is set as a polarized reflection surface, which has the characteristics of reflecting one polarization light and transmitting the polarization light perpendicular to the reflected light, for example, a metal wire grid polarizing film has the above characteristics, which can be attached to the surface of the optical lens. And a phase retardation plate 6 is added to the system to improve the light energy efficiency. Preferably, the phase retardation plate 6 is a quarter-wave plate.

[0061] According to the position of the micro display 4, there are two different cases, as shown in Figure 3 (a) When the micro display 4 is located between the inner lens 2 and the concave partial mirror 3, a phase retardation plate 6 is placed between the micro display 4 and the inner lens 2, which can be attached to the convex surface 2-2 of the inner lens, as shown in Figure 3 (b) The light path and polarization change diagram is shown, the micro display 4 emits first circularly polarized light 7-3, which is reflected by the concave partial mirror 3, and the rotation direction changes, such as left rotation to right rotation, becoming second circularly polarized light 7-4, the second circularly polarized light 7-4 passes through the phase retardation plate 6 and becomes p-type linearly polarized light 7-2, which is completely reflected by the polarized reflection film attached to one of the surfaces of the inner lens 2, and the p-type linearly polarized light 7-2 passes through the phase retardation plate 6 again and becomes second circularly polarized light 7-4, which is reflected by the concave partial mirror 3 and the rotation direction changes, becoming first circularly polarized light 7-3, which passes through the phase retardation plate 6 and becomes s-type linearly polarized light 7-1, which can pass through the polarized reflection film and reach the eye pupil position 1. Thus, a high-energy and low-stray light display effect is achieved. The p-type and s-type linearly polarized light are named for convenience of description, and are not limited to the direction.

[0062] As shown in Figure 4As shown in (a), when the microdisplay 4 is located to the left of the inner lens 2, a phase delay plate 6 is placed between the inner lens 2 and the concave partial reflector 3. It can also be attached to the convex surface 2-2 of the inner lens or the inner surface 3-1 of the concave partial reflector 3. Figure 4 (b) shows the optical path and polarization change diagram. The microdisplay 4 emits unrestricted polarized light 7-5. The unrestricted polarized light 7-5 is light without a restricted polarization form, such as natural light, circularly polarized light, elliptically polarized light, or linearly polarized light. However, when it is linearly polarized light, the polarization direction should not be perpendicular to the transmission direction of the polarization reflective film, otherwise it will not be able to pass through the polarization reflective film. Unrestricted polarized light 7-5 passes through the polarization reflection film attached to the inner lens 2 and becomes S-shaped linearly polarized light 7-1. After passing through the phase retardation plate 6, it becomes first circularly polarized light 7-3. The first circularly polarized light 7-3 is reflected by the concave part of the reflector 3, and its rotation direction changes (e.g., from left to right), becoming second circularly polarized light 7-4. The second circularly polarized light 7-4 passes through the phase retardation plate 6 and becomes P-shaped linearly polarized light 7-2. It is completely reflected by the polarization reflection film attached to one surface of the inner lens 2. The reflected P-shaped linearly polarized light 7-2 passes through the phase retardation plate 6 and becomes second circularly polarized light 7-4 again. The second circularly polarized light 7-4 is reflected by the concave part of the reflector 3, and its rotation direction changes, becoming first circularly polarized light 7-3. The first circularly polarized light 7-3 passes through the phase retardation plate 6 and becomes S-shaped linearly polarized light 7-1. The S-shaped linearly polarized light 7-1 can completely pass through the polarization reflection film and reach the pupil position 1. This achieves a high-energy-efficiency, low-stray-light display effect. This method is well-suited for cases where the microdisplay is a transparent display 4b, as there are no specific requirements regarding the polarization of the light emitted by the microdisplay. However, to reduce the amount of light emitted directly from the transparent display 4b towards the human eye, a dynamic light-blocking layer can be added to block it.

[0063] In this embodiment, to achieve uniformity in the clarity of the displayed image, the inner lens 2, the concave reflector 3, and the microdisplay 4 are distributed on a concentric sphere, with the center of the sphere being the center of the pupil position 1. Since the human eye has a zoom adjustment function, a certain degree of movement or surface deformation of each component is allowed. This movement additionally serves to adapt to the degree of myopia and achieve dynamic zoom. For example, the relative distance between the inner lens 1 and the concave reflector 3 can be dynamically adjusted to achieve dynamic zoom, which is generally achieved by using a voice coil motor.

[0064] The table below lists the optical design parameters for the microdisplay 4 when it is positioned between the inner lens 2 and the concave reflector 3, with one of the reflections occurring three times. These parameters are listed only once, starting from the virtual image position, since the position and shape of the device do not change during the folding process.

[0065]

[0066]

[0067] The following table lists the optical design parameters for one of the micro-displays 4 on the left side of the inner lens 2. The parameters are listed once from the virtual image position, as the position and shape of the device does not change during the folding process.

[0068] Surface markings and surface type Radius of curvature (mm) Thickness (mm) Material virtual image ∞ -1500 - Exit pupil position ∞ 21.6 Air 2-1 spherical -21.6 1 BK7 2-2 spherical -22.6 6.4 Reflective coating, air 3-1 spherical -29 1 BK7 3-2 spherical -30 -8.75 Reflective coating 4 spherical -21.25 - -

[0069] If one of the surfaces of the inner lens 2 is involved in the generation of the virtual image, the curvature of the other surface can be varied as a surface for myopia correction to adapt to the user's prescription. The same can be done for both surfaces of the concave partial mirror 3 to adjust the prescription.

[0070] In order to improve the energy utilization, one of the surfaces of the concave partial mirror 3 can be coated with a reflective filter film designed according to the light emitting wavelength of the micro-display 4. The reflective filter film has high reflectivity, such as greater than 90% reflectivity, for the central wavelength of the light emitted by the micro-display 4, and high transmittance, such as greater than 90% transmittance, for wavelengths other than the central wavelength. Such a design can simultaneously improve the brightness of the ambient light and the virtual image. The reflective filter film can be a dielectric film layer, a dielectric-metal combined film layer, a holographic film layer, and a microstructure film layer.

[0071] In combination Figure 5 In this embodiment, after the polarization reflection film is added to the inner lens 2, a portion of the ambient light is reflected, and the reflected ambient light is reflected again by the concave partial mirror 3, passes through the phase delay film 6, and becomes stray light after passing through the inner lens 2. In order to eliminate the stray light, an ambient light circular polarizer 15 can be placed on the right side of the concave partial mirror 3 to change the ambient light into first circularly polarized light 7-3, so that it becomes s-type linearly polarized light 7-1 after passing through the phase delay film 6 again, thereby directly entering the human eye. In this way, the ambient light can be prevented from forming stray light. When the concave partial mirror 3 is coated with a reflective filter film for the light emitting wavelength of the micro-display, the ambient light circular polarizer 15 does not need to be placed outside the concave partial mirror 3, because the light reflected by the polarization reflection film on the inner lens 2 will pass through the concave partial mirror 3 and will not form stray light.

[0072] In combination Figures 6 to 8 In this embodiment, when the micro-display 4 is a linear array display, the width of the linear array display is preferably as thin as possible, such as less than 1 mm, and a driving chip can be placed under the light emitting pixel when the linear array screen is manufactured using a silicon substrate. When it is difficult to manufacture a linear array screen with a relatively thin width, the overall width can be widened by a transparent wire without blocking the line of sight. For example, Figure 6As shown, a new linear array display structure is proposed in this embodiment, transparent wires 4a-2 are used to connect the linear array micro display light emitting pixels 4a-1 and the linear array display driving chip 4a-3, the distance between the light emitting pixels 4a-1 and the display driving chip 4a-3 is greater than 1mm;

[0073] When the number of pixels is large, such as more than 1000, multiple linear array display driving chips 4a-3 can be used to control part of the pixels, such as 200, so as to reduce the size of a single control chip and reduce the wiring difficulty. Of course, a structure in which a single chip drives all the pixels is not excluded. Since the linear array display driving chip 4a-3 is usually opaque, the distance between the linear array micro display light emitting pixels 4a-1 and the linear array display driving chip 4a-3 can be increased to 5mm through the transparent wires 4a-2. At this time, the linear array display driving chip 4a-3 is not in the middle position, and due to the visual persistence effect, the linear array display driving chip 4a-3 will disappear from the vision when rotating, avoiding the shielding effect. Figure 6 (a) is an arrangement mode that is mirror symmetrical on the light emitting pixels 4a-1, Figure 6 (b) is an arrangement mode that is symmetrical on the light emitting pixels 4a-1, and since it is a rotating display, 1 / 2 of a rotation can also form a complete image. For example, Figure 7 As shown, the linear array display is arranged in a cross shape, and the linear array display driving chip 4a-3 can be placed on the side edge to avoid shielding by using the transparent wires 4a-2. The cross arrangement can improve the brightness of the rotating image and reduce the required rotation speed. By the same principle, it can be arranged in a four-line arrangement. Here, it is not repeated.

[0074] Figure 8 It is a cross-sectional view of the xz plane of the linear array micro display, and the two side areas 4a-4 of the light emitting pixels can be non-functional transparent areas, or can be used as the function of the inner side lens 2, that is, they are set as polarized reflection surfaces. It can replace the inner side lens 2.

[0075] In order to improve the energy efficiency and reduce stray light, referring to Figure 3 and Figure 4 , the front film layer 4a-5 of the light emitting pixel can be a circular polarized film or a linear polarized film, which is used to change the characteristics of the emitted light, and its size is generally greater than the length covered by the light emitting angle corresponding to the diameter of the system exit pupil. A rotating concave ring 4a-8 is arranged at the back side of the center of the light emitting pixel for rotation.

[0076] In combination with Figure 9 and Figure 10 , it is explained that when the micro display 4 is a linear array display, Figure 9One of the assembly diagrams is shown, the inner lens 2 center can be provided with a rotating shaft 2-4, to limit the radial movement of the linear array micro display 4a, the center rotating shaft can be transparent to reduce the center block, but also can be opaque, but the smaller the better, such as diameter 0.5mm. The fixed position of the rotating shaft can be on the inner lens 2, or on the linear array micro display 4a, similar to the jewel bearing in the watch, the rotating position material can use jewels to improve the life and accuracy. The edge of the linear array micro display 4a is the linear array micro display extension end 4a-6, which is arranged with a permanent magnet as a rotor driven to rotate; a wireless power supply receiving coil is arranged to receive power to power the light emitting device and the driving circuit; a photoelectric position detector such as an encoder is arranged to obtain the accurate position of rotation in real time, and other required peripheral electronic devices such as capacitors and inductors need to be arranged. On the outside of the linear array micro display extension end 4a-6, a linear array micro display inner magnetic ring 4a-7 can be fixed, and outside the linear array micro display inner magnetic ring 4a-7, a restraining magnetic ring 8 is fixed on the frame 12, and the restraining magnetic ring 8 is non-contact with the linear array micro display inner magnetic ring 4a-7, and the axial movement of the micro display 4 is constrained by the magnetic force. The driving coil, wireless power supply coil and position calibration ring can be arranged on the extension end 2-3 of the inner lens, and the above-mentioned devices can also be placed separately on the supplementary function board 9, which is arranged with one or all of the driving coil, wireless power supply coil and position calibration ring. The supplementary function board 9 is fixed on the frame 12.

[0077] As shown in Figure 10 When the light emitting pixels of the linear array micro display 4a are arranged on both sides of the area 4a-4 as a partial reflection surface or a polarized reflection surface, it can reflect light, at this time the reflection film replaces the role of the inner lens 2 reflecting light, therefore, the inner lens 2 can become a non-reflective inner protective lens 10 to protect the rotating structure, and provide rotating support through the inner protective lens rotating shaft 10-1 in the middle.

[0078] In combination Figure 11 And Figure 12 The embodiment is described, the concave partial mirror 3 is arranged as a strip-shaped partial mirror 3a, the width of which determines the exit pupil diameter, which generally needs to be greater than the pupil of the human eye, and the preferred range is 6-15mm. The strip-shaped partial mirror 3a rotates synchronously with the linear array micro display 4a. At this time, the rotating structure at the linear array micro display 4a can be selected Figure 9 And Figure 10One type. An outer protective lens 11 is placed on the right side of the strip-shaped reflector 3a. An outer protective lens pivot 11-1 can also be set at the center of the outer protective lens 11 to support rotation. Similarly, it can be made of transparent material. Since rotational pivots are set at both the front and rear, rotational stability is improved. At this time, the axial magnetic fixing structure formed by the binding magnetic ring 8 and the magnetic rings 4a-7 inside the linear array microdisplay can be eliminated, but maintaining this structure can further improve stability, especially when the user moves, causing a change in the angular momentum of the rotating component. The magnetic force of the outer ring easily generates a large torque to change the angular momentum of the rotating structure. For example... Figure 12 The diagram shows a three-dimensional structure of a linear array microdisplay 4a and a strip-shaped concave mirror 3a rotating synchronously.

[0079] Combination Figure 13-16 This implementation method is described as follows: Figure 13 As shown, when the microdisplay 4 is located to the right of the concave part of the reflector 3, the microdisplay 4 emits light toward the pupil position 1, and the light is reflected 4 times between the inner lens 2 and the concave part of the reflector 3.

[0080] The light emitted from the microdisplay 4 first passes through the concave reflector 3 and reaches one of the surfaces of the inner lens 2. This surface, either the concave surface 2-1 or the convex surface 2-2, has a certain reflectivity and can reflect the light. The reflected light then reaches the concave reflector 3 again, which reflects it once more. The light is then reflected again by one of the surfaces of the inner lens 2, and finally, after being reflected once more by the concave reflector 3, it passes through the inner lens 2 and reaches the human eye. The light undergoes a total of four reflections between the inner lens 2 and the concave reflector 3.

[0081] like Figure 14 As shown, when the microdisplay 4 is located between the inner lens 2 and the concave part of the reflector 3, the microdisplay 4 emits light towards the pupil position 1, and the light is reflected 4 times between the inner lens 2 and the concave part of the reflector 3.

[0082] The light emitted by the microdisplay 4 first reaches one of the surfaces of the inner lens 2. This surface, either the concave surface 2-1 or the convex surface 2-2, has a certain reflectivity and can reflect the light. The reflected light passes through the microdisplay 4 and then reaches the concave partial reflector 3, which reflects it again. After passing through the microdisplay 4, the light is reflected again by one of its surfaces, then passes through the microdisplay 4 again and is reflected by the concave partial reflector 3. Finally, the light passes through the microdisplay 4 and the inner lens 2 again before reaching the human eye. The light undergoes a total of four reflections between the inner lens 2 and the concave partial reflector 3.

[0083] Due to the back and forth folding of light, the light energy is constantly lost, and there will be a certain stray light. In order to optimize this problem, as shown in Figure 15 (a), because the pupil of the human eye is generally larger than 3mm, when there is a gap smaller than the pupil in the center, part of the light will also reach the human eye imaging. Based on the above principle, the inner lens 2 is set as a strip shape consistent with the pixel arrangement direction of the linear array micro display 4a, and it rotates synchronously with the linear array micro display 4a. The center of the inner lens 2 is coated with a strip-shaped center total reflection film 13, and the width of the center total reflection film 13 should be smaller than the diameter of the pupil of the human eye, and the preferred range is 0.5mm-1.5mm.

[0084] As shown in Figure 15 (b), on both sides of the center total reflection film 13, one surface of the inner lens 2, i.e. the concave surface 2-1 or the convex surface 2-2, is set as a polarized reflection surface. The polarized reflection surface has the characteristics of reflecting one polarized light and transmitting the polarized light perpendicular to the reflected light, for example, the metal wire grid polarizing film has the above characteristics, which can be attached to the surface of the optical lens. And add a phase delay plate 6 in the system to improve the light energy efficiency. Preferably, the phase delay wave plate 6 is a quarter wave plate.

[0085] Figure 15 (b) is a schematic diagram of polarization change when the linear array micro display 4 is located between the inner lens 2 and the concave partial reflector 3. The micro display 4 emits s-type linearly polarized light 7-3, which is reflected by the strip-shaped center total reflection film 13, and the polarization property remains unchanged. The reflected light becomes second circularly polarized light 7-4 after passing through the phase delay wave plate 6, and the circularly polarized direction changes after being reflected by one of the surfaces of the concave partial reflector 3, becoming first circularly polarized light 7-3. After passing through the phase delay wave plate 6 again, it becomes p-type linearly polarized light 7-2, which is then fully reflected by the polarized reflection film attached to one surface of the inner lens 2, and the polarization property remains unchanged. The reflected light passes through the phase delay wave plate 6 again, becomes first circularly polarized light 7-3, and the circularly polarized direction changes after being reflected by one of the surfaces of the concave partial reflector 3, becoming second circularly polarized light 7-4. After passing through the phase delay wave plate 6 again, it becomes s-type linearly polarized light 7-1, which can fully pass through the polarized reflection film to reach the eye pupil position 1. Thus, a high-energy and low-stray-light display effect is achieved.

[0086] In this embodiment, when the linear array micro display 4a is located on the right side of the concave partial reflector 3, only a polarized film layer needs to be placed in front of the linear array micro display 4a, so that the light reaching the center total reflection film 13 position is s-type linearly polarized light. The width of the polarized film layer should be relatively narrow to prevent a large amount of light reflected by the center total reflection film 13 from passing through, so that the light energy entering the human eye is reduced.

[0087] In combination with Figure 16The present embodiment is described below, Figure 16 (a) shows a schematic diagram of the assembly of the light rays through the four-reflection system described in this embodiment when a linear micro-display 4a is used. Since the linear micro-display 4a needs to be rotated synchronously with the inner side lens 2 in a strip shape, an inner side protective lens 10 needs to be added near the human eye side, and an outer side protective lens 11 needs to be added away from the human eye side, Figure 16 (b) shows an xz cross-sectional view of a linear micro-display 4a. The areas 4a-4 on both sides of the light-emitting pixels can be set as partially reflective surfaces, thereby replacing the function of the concave partial mirror 3. The inner side protective lens 10 and the outer side protective lens 11 can each be provided with a rotation shaft to improve stability. The rotation shaft can be made of transparent material to avoid obstruction.

[0088] In the present embodiment, in order to achieve uniformity of the display image definition, the inner side lens 2, the concave partial mirror 3, and the micro-display 4 are distributed on concentric spherical surfaces, and the center of the sphere is the center of the eye pupil position 1. Since the human eye has a zoom adjustment function, a certain degree of movement of the positions of the components or deformation of the surface shape is allowed. Such movement has the additional effect of being able to adapt to myopia degrees and achieve dynamic zooming. For example, the relative distance between the inner side lens 1 and the concave partial mirror 3 can be dynamically adjusted to achieve dynamic zooming. This zooming function can generally be achieved by setting a voice coil electrode.

[0089] The following table lists the optical design parameters when one of the micro-displays 4 is between the inner side lens 2 and the concave partial mirror 3, and the number of reflections is four. The parameters are listed from the virtual image position. During the folding process, the positions and shapes of the devices do not change, so only one set of parameters is listed.

[0090] Surface markings and surface type Radius of curvature (mm) Thickness (mm) Material virtual image ∞ -1500 - Exit pupil position ∞ 21.2 Air 2-1 spherical -21.2 1 PMMA 2-2 spherical -22.2 5.06 Reflective coating, air 3-1 spherical -27.26 1 PMMA 3-2 spherical -28.26 -1.2 Reflective coating 4 spherical -27.06 - -

[0091] The following table lists the optical design parameters when one of the micro-displays 4 is on the right side of the concave partial mirror 3 and the number of reflections is four. The parameters are listed from the virtual image position. During the folding process, the positions and shapes of the devices do not change, so only one set of parameters is listed.

[0092] Surface markings and surface type Radius of curvature (mm) Thickness (mm) Material virtual image ∞ -1500 - Exit pupil position ∞ 22.1 Air 2-1 spherical -22.1 1 Reflective coating, PMMA 2-2 spherical -23.1 4.146 Air 3-1 spherical -27.25 1 PMMA 3-2 spherical -28.25 0.2 Reflective coating 4 spherical -28.45 - -

[0093] If one of the surfaces of the inner side lens 2 participates in the generation of the virtual image, the curvature of the other surface can be changed as a surface for myopia correction to adapt to the user's degree. The same treatment can be applied to the two surfaces of the concave partial mirror 3 to adjust the degree.

[0094] To improve energy efficiency, one side of the concave reflector 3 can be coated with a reflective filter film, which is designed according to the emission wavelength of the microdisplay 4. This reflective filter film has high reflectivity (greater than 90%) for the center wavelength of the emission from the microdisplay 4, while having high transmittance (greater than 90%) for wavelengths outside the center wavelength. This design can simultaneously improve the brightness of ambient light and virtual images. The reflective filter film can be a dielectric film, a dielectric-metal composite film, a holographic film, or a microstructure film.

[0095] Combination Figures 17 to 20 This implementation method is described as follows: Figure 17 As shown, the light emitted by the microdisplay 4 is reflected back and forth between the concave part reflector 3 and the inner lens 2 at least 5 times before passing through the inner lens 2 and reaching the human eye. When the microdisplay 4 is positioned between the inner lens 2 and the pupil position 1, the microdisplay 4 emits light away from the pupil position, and the number of reflections of the light emitted by the microdisplay 4 between the inner lens 2 and the concave part reflector 3 is an odd number ≥ 5, such as 7, 9, or 11.

[0096] When the microdisplay 4 is positioned between the inner lens 2 and the concave part of the reflector 3, the microdisplay 4 can emit light either away from or towards the pupil position 1. When emitting light away from the pupil position 1, the number of reflections of the light emitted by the microdisplay 4 between the inner lens 2 and the concave part of the reflector 3 is an odd number of ≥5, such as 7, 9, or 11. When emitting light towards the pupil position 1, the number of reflections of the light emitted by the microdisplay 4 between the inner lens 2 and the concave part of the reflector 3 is an even number of ≥6, such as 6, 8, or 10.

[0097] When the microdisplay 4 is positioned to the right of the concave part of the reflector 3, the microdisplay 4 emits light toward the pupil position 1. The light emitted by the microdisplay 4 is reflected between the inner lens 2 and the concave part of the reflector 3 an even number of times, such as 6, 8, or 10, with a reflection number ≥ 6.

[0098] One surface of the inner lens 2 is designated as a switchable mirror, controlling the microdisplay 4 to emit pulsed light. When the number of reflections has not reached the designed number (e.g., 8 times), the switchable mirror reflects the light. When the designed number of reflections is reached, the switchable mirror becomes a transmission state, transmitting the light into the human eye. This optical method can further reduce the thickness.

[0099] In this embodiment, when the number of reflections between the inner lens 2 and the concave partial reflector 3 is greater than 4, one of the surfaces of the inner lens 2 can be set as a polarizing reflective surface. A phase delay plate 6 is added between the inner lens 2 and the concave partial reflector 3. Part of the reflective surface of the concave partial reflector 3 is set as a surface whose circular polarization reflection direction can be dynamically adjusted. The microdisplay 4 is controlled to emit pulsed circularly polarized light. The concave partial reflector 3 is set to maintain the circular polarization direction of the reflected light unchanged. When the number of light reflections reaches the designed number, part of the reflective surface of the concave partial reflector 3 becomes a normal mirror surface. After being reflected by the normal mirror surface, the light enters the human eye.

[0100] like Figure 18 The diagram shows the optical path and polarization changes when a portion of the reflective surface of the concave mirror 3 is configured to dynamically adjust the circularly polarized reflection direction. Currently, the function of dynamically adjusting the circularly polarized reflection direction can be achieved through metasurface technology. The microdisplay 4 emits a short pulse of first circularly polarized light 7-3. At this time, the concave mirror 3 is configured to maintain the circularly polarized direction of the reflected light. After being reflected, the light passes through the phase delay plate 6 and becomes p-type linearly polarized light 7-2. It is then totally reflected by the polarization reflection film on the inner lens 2. After passing through the phase delay plate 6, it is still the first circularly polarized light 7-3. After such back-and-forth reflections are repeated 8 times, the portion of the reflective surface of the concave mirror 3 becomes a normal mirror surface. After reflection, the circular polarization direction is reversed, becoming second circularly polarized light 7-4. Finally, after passing through the phase delay plate 6, it becomes s-type linearly polarized light, passes through the inner lens 2, and enters the human eye.

[0101] The following table lists Figure 17 The table shows the optical design parameters of the multiple reflection system. The parameters correspond to the position of the microdisplay 4 between the inner lens 2 and the concave reflector 3. These parameters are listed only once during the folding process, as the position and shape of the device do not change.

[0102] Surface markings and surface type Radius of curvature (mm) Thickness (mm) Material virtual image ∞ -1500 - Exit pupil position ∞ 24.764 Air 2-1 spherical -24.764 1 PMMA, with reflective coating 2-2 spherical -25.764 1.236 Air 3-1 spherical -27 1 PMMA 3-2 spherical -28 -0.2 Reflective coating 4 spherical -27.385 - -

[0103] Combination Figure 19 and 20 In this embodiment, as the number of folds increases, the distance between the inner lens 2 and the concave reflector 3 becomes very small, allowing them to be combined into a single integrated lens 14. The microdisplay 4 can be placed on the left or right side of the integrated lens 14. Light is reflected back and forth between the inner surface 14-1 and the outer surface 14-2 of the integrated lens a set number of times, such as 8 times, before passing through the inner surface 14-1 and entering the human eye.

[0104] In this embodiment, to achieve uniformity in the clarity of the displayed image, the integrated lens 14 and the microdisplay 4 are distributed on a concentric spherical surface, with the center of the sphere being the center of the pupil position 1. Since the human eye has a zoom adjustment function, a certain degree of movement or surface deformation of the components is allowed. This movement additionally enables adaptation to myopia and achieves dynamic zoom. This zoom function is generally achieved by setting voice coil electrodes.

[0105] The following table lists Figure 19 The optical design parameters of the system are shown. The data in the table indicates that the microdisplay 4 is located to the left of the integrated lens 14. These parameters are listed only once during the folding process because the position and shape of the device do not change.

[0106] Surface markings and surface type Radius of curvature (mm) Thickness (mm) Material virtual image ∞ -1500 - Exit pupil position ∞ 26.005 Air 13-1 spherical -26.005 2.014 PMMA 13-2 spherical -28.019 -2.514 Reflective coating 4 spherical -25.504 - -

[0107] To improve energy efficiency and reduce stray light after multiple folds, the inner surface 14-1 of the integrated lens can be configured as a switchable mirror. This switchable mirror can be electronically controlled to either transmit or reflect light. The microdisplay 4 emits pulsed light. When the number of reflections has not reached the designed number, the switchable mirror reflects the light. When the designed number of reflections is reached, the switchable mirror switches to a transmission state, transmitting the light into the eye. This achieves a high-efficiency, low-stray-light effect.

[0108] In this application, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a system, product, or device that includes a series of units is not necessarily limited to those units that are explicitly listed, but may include other units that are not explicitly listed or that are inherent to such products or devices.

[0109] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0110] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A portable short-focus near-eye display system, comprising a micro display (4), an inner lens (2) and a concave partial mirror (3); the inner lens (2) is close to the eye pupil position (1), and the concave partial mirror (3) is away from the eye pupil position (1); the micro display (4) is a rotating linear array micro display (4a) or a transparent micro display (4b); and the inner lens (2) is a convex mirror; the inner lens (2), the concave partial mirror (3) and the micro display (4) are distributed on a concentric sphere, and the center of the sphere is the center of the eye pupil position (1); characterized in that: the micro display (4) is arranged on the convex side of the concave partial mirror (3), the micro display (4) emits light towards the eye pupil position, and the light emitted by the micro display (4) is reflected between the inner lens (2) and the concave partial mirror (3) for more than or equal to 4 times.

2. The portable short-focus near-eye display system according to claim 1, characterized in that: when the light emitted by the micro display (4) is reflected between the inner lens (2) and the concave partial mirror (3) for more than 4 times, one surface of the inner lens (2) is arranged as a switch mirror, and the micro display (4) emits pulsed light; when the number of reflections does not reach the designed number of times, the switch mirror reflects the light; and when the number of reflections reaches the designed number of times, the switch mirror becomes a transmission state and transmits the light into the human eye.

3. The portable short-focus near-eye display system according to claim 2, characterized in that: the inner lens (2) and the concave partial mirror (3) are combined into an integrated lens (14), the micro display (4) is arranged to emit light towards one side of the integrated lens (14), and the inner surface (14-1) of the integrated lens is arranged as a switch mirror; the light emitted by the micro display (4) is reflected between the inner surface (14-1) of the integrated lens and the outer surface (14-2) of the integrated lens; and when the number of reflections reaches the designed number of times, the light transmits through the inner surface (14-1) of the integrated lens into the human eye. ​ ​ ​ ​ ​ ​

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