TW202024752A - near-eye augmented reality device - Google Patents

Abstract

This invention provides a near-eye augmented reality device, which includes an imaging unit, a lighting unit, and a polarization control unit. The imaging unit comprises a plurality of imaging part which has birefringence property and positive diopter. The lighting unit is spaced from the imaging unit, which comprises a transparent substrate and a plurality of pixel group that are disposed on the transparent substrate and can produce an imaging light. The polarization control unit can control the polarization state of the imaging light and an ambient light.

Description

Near-eye augmented reality device

The invention relates to an imaging device, in particular to a near-eye augmented reality device.

The augmented reality (AR) device can combine and interact with the virtual world on the screen and the real world scene. In order to provide users with environmental images, the augmented reality device must be equipped with a suitable optical path to generate optical transmission. Optical see-through (OST) images are generally divided into two types: projection type and waveguide type.

The projection-type augmented reality device focuses on lightness, so it is hoped that the internal optical system can achieve the best effect with the smallest structure. The principle is to use a micro projector and a micro display to project the image of the virtual world, and then half reflection With a half-penetrating optical combiner, it directly reflects the light source projected from the micro-projector to the user's eyes to produce an enlarged virtual image, and the real world light enters the user directly through the optical combiner In the eyes, the virtual image and the real image can be superimposed to achieve the augmented reality effect.

However, the optical synthesizer is usually a free-form optical element with refractive power, which is prone to aberration. Therefore, an additional freeform corrector (freeform corrector) is required to solve the distortion effect of the optical synthesizer on the environmental image. In addition, the field of view (FOV) of the projected augmented reality device is inseparable from the overall system volume. According to geometric optics, it is assumed that the eye-relief (eye-relief) is D, the field of view (FOV) is α, and the optical The diameter of the synthesizer must be greater than or equal to 2Dtan(α/2). Therefore, if the projection-type augmented reality device is required to be light and convenient, the field of view (FOV) will not be large enough, resulting in insufficient immersion experience.

Another waveguide type augmented reality device, the principle is that the light emitted by a micro display enters the waveguide from an optical element, and after a certain distance of reflection and propagation in the waveguide, it then passes through another optical element to converge. The waveguide itself is penetrative, so the environment image can penetrate the waveguide and be seen directly by the user. Among them, the aforementioned optical element can be a geometrical optical reflector, a diffractive optical element (diffractive optical element). element, DOE), or holographic optical element (HOE).

However, the field of view (FOV) of the waveguide-type augmented reality device is limited by the working principle of the aforementioned optical element and the formation condition of total reflection in the waveguide. In other words, the diffraction efficiency of the diffractive optical element (DOE) will decrease with the field of view (FOV). Therefore, the field of view of the waveguide type augmented reality device of the diffractive optical element (DOE) or holographic optical element (HOE) (FOV) is restricted by this physical principle and cannot be too large. In addition, if continuous total reflection is to occur in the waveguide, basic geometric relationships must also be observed. Various restrictions make it difficult for the existing waveguide-type augmented reality device to have a field of view (FOV) exceeding 50° diagonal.

From the shortcomings of the aforementioned two technical architectures, it can be seen that the field of view (FOV) of the projection-type augmented reality device is inseparable from the system volume; the field of view (FOV) of the waveguide-type augmented reality device is restricted by the working principle of the optical element And the conditions for total reflection in the waveguide. Therefore, neither the projection AR device nor the waveguide AR device can simultaneously have a high field of view (FOV) and be thin and light.

Therefore, the purpose of the present invention is to provide a near-eye augmented reality device.

Therefore, one embodiment of the near-eye augmented reality device of the present invention includes an imaging unit, a light-emitting unit, and a polarization control unit.

The imaging unit includes a plurality of imaging sections with birefringence properties and positive refractive power.

The light emitting unit is spaced apart from the imaging unit, and includes a transparent substrate and a plurality of pixel groups. The transparent substrate has a first surface adjacent to the imaging unit and a second surface opposite to the first surface. The pixel groups are respectively arranged on the first surface at intervals corresponding to the imaging parts, and can generate image light traveling toward the imaging unit.

The polarization control unit includes a plurality of first polarizers and a second polarizer. The first polarizers are respectively arranged on the pixel groups, and the second polarizer is arranged on the second surface. When the image When light passes through the first polarizers, it will be converted into a polarized light with polarization in the first direction and deflected by the imaging unit. When an external ambient light passes through the second polarizer, it will be converted into a polarized light with the first polarization. The polarized light polarized in the second direction perpendicular to the direction is not deflected by the imaging unit.

In addition, another embodiment of the near-eye augmented reality device of the present invention includes an imaging unit, a light-emitting unit, and a polarization control unit.

The imaging unit includes a plurality of imaging sections with birefringence properties and positive refractive power.

The light-emitting unit is spaced apart from the imaging unit, and includes a light-transmitting substrate, and a plurality of pixels arranged on the light-transmitting substrate, and can generate image light traveling toward the imaging unit.

The polarization control unit and the imaging unit are spaced apart and located on the side opposite to the light-emitting unit, and include an electrically controlled adjustment layer and a polarizer, and the electrically controlled adjustment layer is located between the imaging unit and the polarizer The image light or an external ambient light is split into a polarized light with a polarization in the first direction and a polarized light with a polarization in the second direction by the imaging unit. When a voltage is applied to the electrically controlled adjustment layer, a second The polarization state of the polarized light of the direction polarization is unchanged, and when no voltage is applied to the electric control adjustment layer, the polarized light having the polarization in the first direction is changed to the polarized light having the polarization in the second direction.

The effect of the present invention is that image light is generated through the light-emitting unit and the ambient light can be directly penetrated, and the imaging unit has the characteristics of birefringence and positive refractive power, and the image light can be deflected and extended to form a virtual image and converge The light has the magnifying effect, thereby taking into account both high light transmittance and high field of view, and the polarization control unit controls the image light deflected by the imaging unit to enter the user's eyes, and controls the ambient light not to be deflected by the imaging unit. Enter the eyes of the user, so that the user can see the normal and undistorted image of the external environment, and through the imaging parts, the individual points of the image light can be focused on planes of different depths, thereby generating depth 3D images with angle information.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are represented by the same numbers.

1 to 2, a first embodiment of the near-eye augmented reality device of the present invention is suitable for a user to wear in front of his eye E, and the near-eye augmented reality device includes an eye adjacent to the user The imaging unit 2 of E, and a light-emitting unit 3 and a polarization control unit 4 that are spaced apart from the imaging unit 2. Wherein, FIG. 2 is a partial front view of FIG. 1 from the perspective of the user's eye E. In this embodiment, the surfaces of the imaging unit 2 and the light-emitting unit 3 are flat, but the overall shape is not smaller than that of the user. It has a curved structure suitable for the curvature of the eye relief, but it is not limited to this, and it may also be a flat shape without curvature.

The imaging unit 2 includes two plane substrates 21 arranged at intervals, and a birefringent material 22 arranged between the substrates 21. One of the substrates 21 has a plurality of penetration regions 210 arranged in an array. The birefringent material 22 is twisted and arranged to have positive refractive power under a voltage. Therefore, the penetrating regions 210 and the birefringent material 22 together form a plurality of imaging parts 20, so that the imaging parts 20 have birefringence Nature and positive refractive power.

In detail, in this embodiment, the substrates 21 are made of transparent glass with a transparent conductive layer, and the birefringent material 22 is selected from liquid crystals as an example. On the surface of one of the substrates 21 A plurality of arrays are scribed and arranged in a hexagonal structure to form the light-transmitting regions 210. Each light-transmitting region 210 in a hexagonal structure is matched with a liquid crystal material with birefringence properties, and applied to the substrate 21 The voltage causes the liquid crystals to be aligned to have positive refractive power, thereby constituting the imaging unit 20.

The light-emitting unit 3 is spaced apart from the imaging unit 2, and includes a light-transmitting substrate 31 and a plurality of pixel groups 32. The light-transmitting substrate 31 has a first surface 311 adjacent to the imaging unit 2 and an opposite first surface 311. On the second surface 312 of a surface 311, the pixel groups 32 are respectively arranged on the first surface 311 at intervals corresponding to the imaging portions 20, and can generate a light penetrating the imaging unit 2 and projecting into the user The image light I in the eye E (each pixel group 32 emits light, FIG. 1 only uses a single pixel group 32 as an example), the user can see through the light-transmitting area 210 and the light-transmitting substrate 31 Ambient light to the outside world.

In detail, each pixel group 32 is set corresponding to each light-transmitting area 210, that is, the orthographic projection of each light-transmitting area 210 to the light-emitting unit 3 will cover a pixel group 32. The pixel groups 32 are not penetrated by ambient light A. Therefore, in this embodiment, the area of the orthographic projection of each pixel group 32 to the light-transmitting area 210 (imaging part 20) is not It is larger than 25% of the area of the light-transmitting area 210 (the imaging part 20). More preferably, the area ratio of the pixel group 32 to the hexagonal light-transmitting area 210 is about 25% to 75%, and the pixel groups 32 can be selected from micro LEDs, Organic light-emitting diodes (OLED), or thin-film transistors with liquid crystals (that is, thin-film transistors liquid crystal display TFT-LCD), in this embodiment, a micro-light-emitting diode is taken as an example for illustration, so that the light-emitting unit 3 A curved micro-light-emitting diode display is formed.

The polarization control unit 4 includes a plurality of first polarizers 41 and a second polarizer 42. The first polarizers 41 are respectively disposed on the pixel groups 32, and the second polarizer 42 is disposed on the transparent plate. On the second surface 312 of the optical substrate 31, when the image light I passes through the first polarizers 41, it is converted into a polarized light having a polarization in the first direction. When an ambient light A passes through the second polarizer 42 , Will be converted into a polarized light with polarization in the second direction perpendicular to the first direction, and will not pass through the first polarizers 41. In this embodiment, the first polarizer 41 and the second polarizer 42 are linear polarizers with directions perpendicular to each other, and the polarized light with the first direction polarization is p-polarized light, and the second polarizer is polarized light. This polarized light is s-polarized light.

In detail, the directions of the first polarizers 41 and the second polarizers 42 are perpendicular, so that the first polarizers 41 can generate s-polarized light from the light passing through, and the second polarizers 42 can pass through The light produces p-polarized light (relative to the horizontal plane). Therefore, by allowing the imaging parts 20 of the imaging unit 2 to have a positive refractive power and set close to the user's eye E, and to allow an appropriate separation distance between the imaging unit 2 and the light emitting unit 3 to match the polarization The control unit 4 thus uses the principle of spatial multiplexing to work.

In more detail, since the imaging unit 2 has birefringence characteristics, the pixel groups 32 generate unpolarized image light I, which is first polarized by the first polarizers 41 before being projected to the imaging unit 2 Converted into p-polarized light, and then deflected by the imaging unit 2 to enter the user's eye E, where the area of each pixel group 32 is reduced to the penetration area 210 in consideration of the light transmittance of the overall device 25% of that, the effective light-emitting area of the pixel group 32 is also reduced at the same time, but the imaging parts 20 passing through the imaging unit 2 are arranged in an array and have a positive refractive power with a magnifying effect, and the adjacent imaging parts 20 The virtual images generated by the image light I projected by the pixel group 32 are spliced with each other to form a virtual image of a curved surface structure with a large viewing angle, thereby taking into account high light transmittance and high field of view (FOV). In addition, when the external environment is unbiased and polarized The light A passes through the second polarizer 42 and is polarized into s-polarized light, and then enters the user's eye E without being deflected by the imaging unit 2, so that the user can see normal without being Distorted image of the external environment.

It should be particularly noted here that the imaging unit 2 and the light-emitting unit 3 of this embodiment have a curved structure as a whole and are not less than the curvature radius of the eye-fitting distance. At different viewing angles, the image light I emitted by the light-emitting unit 3 is The part of the imaging unit 2 that enters the user's eye E after being deflected is closer to the paraxial light. Therefore, the imaging aberration can be greatly reduced, the field of view (FOV) will be increased due to this, and the entire system volume can be compressed smaller. . In addition, the imaging unit 2 includes a plurality of imaging parts 20 arranged in an array with positive refractive power, which can focus individual points of the image light I through the imaging parts 20 arranged in the array on planes of different depths, thereby generating a depth 3D images with angle information.

Referring to FIG. 3, the structure of a second embodiment of the near-eye augmented reality device of the present invention is substantially the same as that of the first embodiment, except for the aspect of the imaging unit 2. Specifically, in the second embodiment, the imaging unit 2 is not a plane, but directly allows the substrate 21 to have a plurality of protrusions 23 arranged in an array, and a birefringent material is arranged in the protrusions 23 22. The projections 23 and the birefringent material 22 inside constitute the imaging parts 2. In detail, the protrusions 23 are in the form of lenses with positive refractive power, and the birefringent material 22 is selected from quartz, and directly constitutes the imaging portion 20 with birefringent properties and positive refractive power, without the need for the One embodiment applies voltage.

4 and 5, the structure of a third embodiment of the near-eye augmented reality device of the present invention is substantially the same as that of the first embodiment, except that the light emitting unit 3 and the polarization control unit 4 are different. Specifically, the light-emitting unit 3 includes a plurality of pixels 321 directly arranged and covered with the light-transmitting substrate 31. In other words, each of the light-transmitting regions 210 is orthographically projected to the light-emitting unit 3. 321 is used to cover each of the light-transmitting areas 210. In the third embodiment, each of the pixels 321 is a micro LED for illustration, and each pixel 321 It has partial light transmission and partial opacity (i.e. light-emitting place) (as shown in Figure 5). The polarization control unit 4 is spaced apart from the imaging unit 2 and is located on the side opposite to the light-emitting unit 3, and includes an electrically controlled adjustment layer 43 and a polarizer 44. The electrically controlled adjustment layer 43 is located on the imaging unit 2 and the polarizer 44, the image light I or the ambient light A is split into a polarized light having a polarization in the first direction (that is, the aforementioned p-polarized light) and a polarized light having a polarization in the second direction by the imaging unit 2. When a voltage is applied to the electrically controlled adjustment layer 43, the polarization state of the polarized light (s-polarized light) with the second direction polarization (s-polarized light) remains unchanged. When the electrically controlled adjustment layer 43 When no voltage is applied, the polarized light having the polarization in the second direction (s-polarized light) is changed to the polarized light having the polarization in the first direction (p-polarized light).

The electrically controlled adjustment layer 43 suitable for this embodiment is a twisted nematic (TN) liquid crystal module; and the aspect of the imaging unit 2 is also the same as that of the first and second embodiments. For the same example, two flat substrates 21 may be sandwiched with liquid crystal material, or protrusions 23 may be formed on the substrate 21 and a quartz material may be used to form the imaging section 20 with birefringence and positive refractive power. .

In detail, the near-eye augmented reality device of the third embodiment mainly uses the time multiplexing principle of two time states to work. In the first time state, the electronic control adjustment layer 43 (TN liquid crystal module) When a voltage is applied, the s-polarized light passing through it can not be changed, so that the light-emitting unit 3 produces unpolarized image light I, which is split into s-polarized light and p-polarized light after passing through the imaging unit 2, and only p-polarized light Light can pass through the polarizer 44 and enter the user's eyes E, and the unpolarized ambient light A will not be deflected by the imaging unit 2, and will not be deflected by the electronic control adjustment layer 43 (TN liquid crystal module ) Changes the polarization state, but cannot pass through the polarizing plate 44, so as not to be seen by the user; in the second time state, when no voltage is applied to the electric control adjustment layer 43 (TN liquid crystal module), the The light-emitting unit 3 does not emit light. When the unpolarized ambient light A passes through the light-emitting unit 3 and the imaging unit 2, there are still p-polarized light and s-polarized light, but because the imaging unit 2 has birefringence properties, it will Polarized light is focused instead of s-polarized light. When the focused p-polarized light and unfocused s-polarized light enter the electronic control adjustment layer 43 (TN liquid crystal module), the unfocused s-polarized light Will be changed to p-polarized light, and the focused p-polarized light will be converted into s-polarized light. When the converted p-polarized light and s-polarized light pass through the polarizer 44, only p-polarized light will pass and be blocked s-polarized light, so that the unfocused s-polarized light is converted into p-polarized light by the electronic control adjustment layer 43 and penetrates the polarizer 44 to be seen by the user. By quickly switching between the first time state and the second time state, the user can merge the two time states to see a smooth augmented reality fusion image.

In summary, in the near-eye augmented reality device of the present invention, the light-emitting unit 3 generates virtual image light I and allows ambient light A to directly penetrate, and has birefringence and positive refractive power characteristics through the imaging unit 2 The image light I is deflected and extended to form a virtual image and converge the light, and the polarization control unit 4 is used to control the image light I deflected by the imaging unit 2 to enter the user's eye E, and the ambient light A is controlled not to be imaged The unit 2 deflects and enters the user's eye E, so that the user can see a normal and undistorted image of the external environment; in addition, the imaging parts 20 with positive refractive power can individually point the image light I The imaging parts 20 arranged in these arrays are focused on planes of different depths, thereby generating 3D images with depth and angle information; further, the imaging unit 2 and the light-emitting unit 3 are formed into a curved structure as a whole, and at different viewing angles, The image light I emitted by the light-emitting unit 3 is deflected by the imaging unit 2 and enters the part of the user's eye E, which is closer to the paraxial light, the imaging aberration can be greatly reduced, and the field of view (FOV) will increase as a result. The volume of the entire system can also be compressed to be smaller, thereby improving the problems of insufficient field of view of the existing projection-type and waveguide-type augmented reality devices, and the size is not light enough, so it can indeed achieve the purpose of the invention.

However, the foregoing are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, all simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification still belong to Within the scope of the patent of the present invention.

2: imaging unit 32: Pixel Group 20: Imaging Department 321: Pixel 21: Substrate 4: Polarization control unit 210: penetration zone 41: The first polarizer 22: Birefringent material 42: second polarizer 23: protrusion 43: Electronic control adjustment layer 3: Light-emitting unit 44: Polarizer 31: Transparent substrate A: Ambient light 311 First Surface E: eyes 312: second surface I: image light

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: 1 is a schematic cross-sectional side view illustrating a first embodiment of the near-eye augmented reality device of the present invention; Figure 2 is a schematic front view, assisting Figure 1 to illustrate the first embodiment of the present invention; 3 is a schematic cross-sectional side view illustrating a second embodiment of the near-eye augmented reality device of the present invention; 4 is a schematic cross-sectional side view illustrating a third embodiment of the near-eye augmented reality device of the present invention; and Figure 5 is a schematic front view, assisting Figure 4 to illustrate the third embodiment of the present invention

2: imaging unit

20: Imaging Department

21: Substrate

210: penetration zone

22: Birefringent material

3: Light-emitting unit

31: Transparent substrate

311: First Surface

312: second surface

32: Pixel Group

4: Polarization control unit

41: The first polarizer

42: second polarizer

A: Ambient light

E: eyes

I: image light

Claims (7)

A near-eye augmented reality device, including: An imaging unit including a plurality of imaging units arranged in an array and having birefringence properties and positive refractive power; A light emitting unit, which is arranged spaced apart from the imaging unit, includes a light-transmitting substrate, and a plurality of pixels arranged on the light-transmitting substrate, and can generate image light traveling in the direction of the imaging unit, and each imaging unit The orthographic projection of the light-emitting unit covers a plurality of the pixels; and A polarization control unit, which is spaced apart from the imaging unit and located on the side opposite to the light-emitting unit, and includes an electrically controlled adjustment layer and a polarizer, the electrically controlled adjustment layer being located between the imaging unit and the polarizer At the same time, the image light or an external ambient light is split into a polarized light with a polarization in the first direction and a polarized light with a polarization in the second direction by the imaging unit. When a voltage is applied to the electrically-controlled adjustment layer, the first The polarization state of the polarized light polarized in the two directions remains unchanged, and when no voltage is applied to the electrically controlled adjustment layer, the polarized light having the polarization in the second direction is changed to the polarized light having the polarization in the first direction. The near-eye augmented reality device according to claim 1, wherein the imaging unit includes two substrates arranged at intervals, and a birefringent material arranged between the substrates, and the birefringent material can be subjected to a voltage The twist is arranged to have positive refractive power. The near-eye augmented reality device according to claim 2, wherein the birefringent material is selected from liquid crystal. The near-eye augmented reality device according to claim 1, wherein the imaging unit includes a substrate having a plurality of protrusions arranged in an array, and a birefringence disposed on the substrate and located in the protrusions Materials, the protrusions and the birefringent material in them constitute the imaging parts. The near-eye augmented reality device according to claim 4, wherein the birefringent material is selected from quartz or liquid crystal. The near-eye augmented reality device according to claim 1, wherein the electrically controlled adjustment layer is a twisted nematic liquid crystal module. The near-eye augmented reality device according to claim 1, wherein the polarized light having the polarization in the first direction is p-polarized light, and the polarized light having the polarization in the second direction is s-polarized light.

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