Display device and near-eye display equipment

Abstract

The utility model relates to a display device and near-to-eye display equipment, and the display device comprises a display assembly which is used for emitting visible light; the modulation assembly is arranged on the light emitting side of the display assembly; the cholesteric liquid crystal element is arranged on the side, away from the display assembly, of the modulation assembly, and the cholesteric liquid crystal element has a reflection wavelength bandwidth range and is used for reflecting circularly polarized light in the corresponding reflection wavelength bandwidth range and transmitting circularly polarized light in other polarization states and light in other reflection wavelength bandwidth ranges; and the eye movement tracking assembly comprises an infrared light source and an infrared camera and is used for receiving the infrared light reflected by the human eyes. According to the display device, the cholesteric liquid crystal element is used for replacing a polarization reflecting film, the characteristic that the cholesteric liquid crystal element can transmit infrared light is utilized, so that the infrared light emitted by the infrared light source is not affected, the infrared light transmittance can be effectively improved, and the imaging quality of an infrared camera is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of eye tracking, in particular to a display device and a near-eye display equipment. Background Art

[0002] In augmented reality (AR) / virtual reality (VR) devices, eye tracking technology is an important emerging technology. AR / VR devices can transfer the mode of human-computer interaction from gesture recognition to eye movement recognition by capturing the movement of human eyes in real time, making the entire system more practical in terms of interaction logic. At present, the eye tracking system adopts infrared light to recognize eye movement. The infrared light emitted by the infrared light source is reflected by the human eye and then received by a special infrared camera, thereby generating an image with infrared light spots. The system calculates the movement of the human eye through the position of specific infrared light spots, thereby realizing interaction.

[0003] Polarized reflective film (RP film) can reflect light in a linear polarization state and transmit light in another linear polarization state orthogonal to it. Existing AR / VR devices use this property of RP film to form a folded optical system with lenses, quarter-wave plates and beam splitters, which can image the visible light emitted by the display screen. However, due to space limitations, the existing eye tracking system solutions often need to place the infrared light source and infrared camera behind the polarized reflective film (RP film). After the infrared light is emitted from the infrared light source, it needs to pass through the RP film to reach the human eye, and the infrared light reflected by the human eye also needs to pass through the RP film to be received by the infrared camera. Since the RP film itself has a strong reflective effect on infrared light (reflectivity is about 40%), only about 36% of the infrared light is received by the infrared camera, so that when the light source power is fixed, the imaging brightness of the infrared camera decreases due to the weak light energy; in addition, the strong reflection of the RP film is also prone to form serious stray light. Under the combined effect of the two factors, the imaging effect of the infrared camera will be seriously reduced, which will eventually affect the eye tracking effect. Utility Model Content

[0004] Based on this, it is necessary to provide a display device and a near-eye display device to address the problem that the RP film in the eye tracking system of the existing AR / VR equipment has a strong reflective effect.

[0005] A display device, comprising:

[0006] A display component, the display component is used to emit visible light;

[0007] A modulation component, the modulation component is arranged on the light-emitting side of the display component, and is used to modulate the visible light into a first circularly polarized light and reflectively modulate the first circularly polarized light into a second circularly polarized light;

[0008] a cholesteric liquid crystal element, wherein the cholesteric liquid crystal element is arranged on a side of the modulation component away from the display component, the cholesteric liquid crystal element having a reflection wavelength bandwidth range, and used for reflecting the first circularly polarized light in the corresponding reflection wavelength bandwidth range, and transmitting the second circularly polarized light and light in other reflection wavelength bandwidth ranges; and

[0009] An eye tracking component includes an infrared light source disposed between the display component and the cholesteric liquid crystal element and used for emitting infrared light, and an infrared camera disposed between the display component and the cholesteric liquid crystal element and used for receiving the infrared light reflected by the human eye.

[0010] In one embodiment, the cholesteric liquid crystal element includes a plurality of reflective layers arranged in sequence in a direction away from the display component, the reflective layers having different reflection wavelength bandwidth ranges, and being used to respectively reflect the first circularly polarized light within the corresponding wavelength bandwidth ranges and transmit the second circularly polarized light and the infrared light.

[0011] In one embodiment, the reflective layer of the cholesteric liquid crystal element includes a red light reflective layer, a green light reflective layer and a blue light reflective layer arranged in sequence along a direction away from the display component, the red light reflective layer is used to reflect visible light with a central wavelength of red, the green light reflective layer is used to reflect visible light with a central wavelength of green, and the blue light reflective layer is used to reflect visible light with a central wavelength of blue.

[0012] In one of the embodiments, the reflective layer includes an orientation layer and a liquid crystal film layer, and the cholesteric liquid crystals in the liquid crystal film layer are arranged along the orientation direction of the orientation layer.

[0013] In one embodiment, the liquid crystals in the liquid crystal film layer are arranged in a spiral along the normal direction of the alignment layer to form a cholesteric liquid crystal reflection grating.

[0014] In one embodiment, the eye tracking component further includes an optical metasurface element, and the optical metasurface element is arranged on the light emitting side of the infrared light source.

[0015] In one of the embodiments, the modulation component includes a linear polarizer, a quarter wave plate, a beam splitter and a focusing lens group which are sequentially arranged in a direction away from the display component.

[0016] In one embodiment, the eye tracking component is arranged between the cholesteric liquid crystal element and the focusing lens group; or the eye tracking component is arranged between the focusing lens group and the beam splitter; or the eye tracking component is arranged between the beam splitter and the quarter wave plate; or the eye tracking component is arranged between the quarter wave plate and the linear polarizer; or the eye tracking component is arranged between the linear polarizer and the display component.

[0017] In one of the embodiments, the eye tracking component further includes an infrared anti-reflection film, and the infrared anti-reflection film is arranged on a side of the infrared light source and the infrared camera away from the display component.

[0018] A near-eye display device, comprising:

[0019] A display device as described in any one of the above;

[0020] The display device is installed on the device body.

[0021] The above-mentioned display device utilizes the characteristic that cholesteric liquid crystal elements can reflect visible light in a specific band, replaces the polarized reflective film with cholesteric liquid crystal elements, and forms a folded optical system with the modulation component to image the visible light emitted by the display screen. And by utilizing the characteristic that cholesteric liquid crystal elements can transmit infrared light, the infrared light emitted from the infrared light source is not affected, which can effectively improve the infrared light transmittance and improve the imaging quality of the infrared camera. In addition, after using the cholesteric liquid crystal element, the infrared light source in the display device does not need to consider the reflection loss of the polarized reflective film, so the power of the infrared light source of the display device of the present application is lower than that of the existing eye tracking system, which reduces the power consumption of the entire display device and helps to improve the battery life of the near-eye display device. In addition, the cost of cholesteric liquid crystal elements is lower than that of polarized reflective films, and the production process is autonomous and controllable, which can reduce the cost of the display device in the near-eye display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic plan view of a display device provided in accordance with an embodiment of the present application;

[0023] Figure 2 A reflection bandwidth curve diagram of a cholesteric liquid crystal element of a display device according to the above embodiment of the present application is shown;

[0024] Figure 3 A schematic diagram showing a multilayer structure of a cholesteric liquid crystal element of a display device according to the above embodiment of the present application is shown;

[0025] Figure 4 It shows that Figure 3A reflection bandwidth curve of the multilayer cholesteric liquid crystal element shown;

[0026] Figure 5 A schematic diagram of a cholesteric liquid crystal grating of a display device according to the above embodiment of the present application is shown;

[0027] Figure 6 A schematic diagram showing the orientation of the orientation layer of the cholesteric liquid crystal grating of the display device according to the above embodiment of the present application is shown;

[0028] Figure 7 A schematic diagram showing the position of an eye tracking component of a display device according to the above embodiment of the present application is shown.

[0029] Figure numerals: 10, display component; 11, visible light; 111, red light; 112, green light; 113, blue light; 20, modulation component; 21, linear polarizer; 22, quarter-wave plate; 23, beam splitter; 24, focusing lens group; 25, infrared anti-reflection film; 30, cholesteric liquid crystal element; 31, red light reflection layer; 32, green light reflection layer; 33, blue light reflection layer; 34, orientation layer; 35, liquid crystal film layer; 40, eye tracking component; 41, infrared light source; 411, infrared light; 42, infrared camera; 43, optical metasurface element. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0035] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0036] Based on the problem that the RP film in the eye tracking system of the existing AR / VR device has a strong reflective effect, the present application provides a display device and a near-eye display device. The display device uses a cholesteric liquid crystal element 30 (CLC film) instead of the RP film. Based on the high transmittance of the CLC film, the transmittance of the infrared light 411 can be effectively improved, thereby improving the imaging quality of the infrared camera 42.

[0037] For details, please refer to Figure 1, the display device may include a display component 10, a modulation component 20, a cholesteric liquid crystal element 30 and an eye tracking component 40. The display component 10 is used to emit visible light 11. The modulation component 20 is arranged on the light-emitting side of the display component 10, and is used to modulate the visible light 11 into a first circularly polarized light and reflectively modulate the first circularly polarized light into a second circularly polarized light. The cholesteric liquid crystal element 30 is arranged on a side of the modulation component 20 away from the display component 10. The cholesteric liquid crystal element 30 has a reflection wavelength bandwidth range, and is used to reflect the first circularly polarized light in the corresponding reflection wavelength bandwidth range, and transmit the second circularly polarized light and light in other reflection wavelength bandwidth ranges. The cholesteric liquid crystal element 30 and the modulation component 20 cooperate to form a folded optical system, which can modulate the visible light 11 emitted by the display component 10 into an image. The eye tracking component 40 includes an infrared light source 41 and an infrared camera 42, which are arranged between the display component 10 and the cholesteric liquid crystal element 30. The infrared light source 41 is used to emit infrared light 411, and the infrared camera 42 is used to receive the infrared light 411 reflected by the human eye to form an eye diagram containing infrared light spots, and the eye diagram can record human eye information.

[0038] It can be understood that the cholesteric liquid crystal element 30 can achieve greater reflection for incident light of a specific wavelength band and a specific polarization state, and achieve greater projection for incident light of other wavelength bands or other polarization states. Figure 2 As shown, it is a reflection bandwidth curve of an exemplary cholesteric liquid crystal element 30, and the cholesteric liquid crystal element 30 can transmit light in the infrared band, and can reflect light in the band of 600nm to 680nm with a central wavelength of 639nm. Therefore, by utilizing the characteristic that the cholesteric liquid crystal element 30 can reflect visible light 11 in a specific band, the cholesteric liquid crystal element 30 can be used to replace the polarizing reflective film, and form a folded optical system with the modulation component 20 to image the visible light 11 emitted by the display screen. And by utilizing the characteristic that the cholesteric liquid crystal element 30 can transmit infrared light 411, the infrared light 411 emitted from the infrared light source 41 is not affected, and the transmittance of the infrared light 411 can be effectively improved, and the imaging quality of the infrared camera 42 can be improved. In addition, after using the cholesteric liquid crystal element 30, the infrared light source 41 in the display device does not need to consider the reflection loss of the polarizing reflective film, so the power of the infrared light source 41 of the display device of the present application has lower power than the existing eye tracking system, which reduces the power consumption of the entire display device and helps to improve the battery life of the near-eye display device. Furthermore, the cost of the cholesteric liquid crystal element 30 is lower than that of the polarizing reflective film, and the production process is autonomous and controllable, which can reduce the cost of the display device in the near-eye display device.

[0039] More specifically, without interfering with the high transmittance of the cholesteric liquid crystal element in the near-infrared band, the design of the cholesteric liquid crystal element itself is relatively flexible. In one embodiment, the cholesteric liquid crystal element 30 can be designed as a multilayer structure. The cholesteric liquid crystal element 30 includes a plurality of reflective layers arranged in sequence in a direction away from the display component 10, and the reflective layers have different reflection wavelength bandwidth ranges, which are used to respectively reflect the first circularly polarized light within the corresponding wavelength bandwidth range, transmit the second circularly polarized light and the infrared light. By designing a combination of multiple reflective layers with different reflection wavelength bandwidth ranges, the wavelength bandwidth range of the modulated visible light 11 that can be reflected by the cholesteric liquid crystal element 30 can be increased to support some AR / VR optical machine systems with wide spectrum display. And the combination structure of multiple reflective layers does not affect the transmission performance of the infrared light 411, so that the eye tracking component 40 can still work normally.

[0040] For example, Figure 3 As shown, in one embodiment, the reflection layer of the cholesteric liquid crystal element 30 includes a red light reflection layer 31, a green light reflection layer 32 and a blue light reflection layer 33 arranged in sequence in a direction away from the display component 10, the red light reflection layer 31 is used to reflect the visible light 11 with a central wavelength of red, the green light reflection layer 32 is used to reflect the visible light 11 with a central wavelength of green, and the blue light reflection layer 33 is used to reflect the visible light 11 with a central wavelength of blue. It can be seen from the figure that the infrared light 411 can sequentially pass through the red light reflection layer 31, the green light reflection layer 32 and the blue light reflection layer 33, the red light 111 is reflected by the red light reflection layer 31, the green light 112 is reflected by the green light reflection layer 32 after passing through the red light reflection layer 31, and the blue light 113 is reflected by the blue light reflection layer 33 after passing through the red light reflection layer 31 and the green light reflection layer 32.

[0041] like Figure 4 As shown, the cholesteric liquid crystal element 30 can reflect visible light 11 in the wavelength range of 440 nm to 660 nm, while maintaining a relatively high transmittance for infrared light 411 , and the reflectance for infrared light 411 is less than 5%.

[0042] Optionally, in one embodiment, the infrared light source 41 is an infrared LED light source, which can reduce power consumption and save energy consumption of the display device.

[0043] Furthermore, the orientation layer 34 of the cholesteric liquid crystal element 30 can be made into an orientation mode in which the orientation direction is arranged according to a certain rule. In this way, after the cholesteric liquid crystal is coated and solidified, the cholesteric liquid crystal is affected by the orientation layer 34, and the orientation of the liquid crystal optical axis in the same plane changes accordingly, so that the cholesteric liquid crystal can add a phase to the specific rotational polarization light within the wavelength band range that can be reflected and modulated by the cholesteric liquid crystal element 30.

[0044] Therefore, if Figure 5 As shown, in one embodiment, the reflective layer includes an orientation layer 34 and a liquid crystal film layer 35, and the cholesteric liquid crystal in the liquid crystal film layer 35 is arranged along the orientation direction of the orientation layer 34. In this way, the orientation layer 34 can fix the orientation of the cholesteric liquid crystal in the liquid crystal film layer 35, so that the liquid crystal film layer 35 can cooperate with the modulation component 20 to modulate the incident visible light 11 multiple times, forming a more complex optical system for the visible light 11, while the traditional polarized reflective film cannot achieve the above function. In addition, the liquid crystal film layer 35 solidified by the orientation layer 34 does not modulate the infrared light 411 of the eye tracking component 40, so the introduction of the phase modulation function will not affect the normal operation of the eye tracking component 40.

[0045] For example, Figure 5 As shown, in one embodiment, the liquid crystal in the liquid crystal film layer 35 is arranged in a spiral along the normal direction of the orientation layer 34 to form a cholesteric liquid crystal reflection grating. The cholesteric liquid crystal reflection grating can reflect and diffract the light within the wavelength band that can be reflected and modulated by the cholesteric liquid crystal element 30 to the +1 order, while directly transmitting the infrared light 411 outside the modulation wavelength band.

[0046] Alternatively, if Figure 6 Shown is a structural diagram of the reflective layer with different orientation directions in some embodiments of the present application, wherein the orientation direction of the orientation layer 34 includes but is not limited to a direction parallel to the normal direction of the incident surface of the cholesteric liquid crystal element, a direction having an inclined angle with the normal direction of the incident surface of the cholesteric liquid crystal element, or an arrangement direction parallel to the normal direction of the incident surface of the cholesteric liquid crystal element.

[0047] In particular, in order to reduce the size of the equipment, reduce the camera inclination angle, etc., the current existing eye tracking solutions usually need to place the infrared light source inside the AR / VR imaging module. Therefore, the light emitted by the infrared light source needs to be transmitted through one or more lenses to the human eye and then transmitted through one or more lenses to be received by the infrared camera. The infrared light is transmitted through multiple lenses, resulting in the weakening of the light spot energy. At the same time, since the divergence angle of the infrared light source is too large, the light with a large divergence angle is refracted multiple times in the system, resulting in more serious stray light in the eye tracking system. Therefore, in some traditional optical path systems, it is generally necessary to add beam shaping optical elements close to the light source to solve the above problems. Limited by the size and weight of the AR / VR system optical machine, it is difficult for the current existing eye tracking system to add traditional lenses or lens groups for beam shaping.

[0048] Therefore, if Figure 1As shown, in one embodiment, the eye tracking component 40 further includes an optical metasurface element 43, which is arranged on the light-emitting side of the infrared light source 41. The optical metasurface element 43 is a new type of planar optical element that can accurately control parameters such as the amplitude and phase of light. Compared with traditional optical elements, the optical metasurface element 43 has the advantages of being lighter, thinner, low cost of large-scale manufacturing, and stronger light wave control ability. The optical metasurface element 43 can replace traditional lenses or lens groups and be embedded in the eye tracking system, which meets the volume restrictions of the optical-mechanical system on beam shaping devices. The optical metasurface element 43 can beam shape the infrared light 411 emitted by the infrared light source 41, reduce the stray light in the eye diagram captured by the infrared camera 42, and improve the eye tracking performance of the display device. In addition, the optical element surface area of ​​the optical metasurface element 43 is small, the processing is relatively simple, and the batch processing cost is low.

[0049] Furthermore, if Figure 1 As shown, in one embodiment, the modulation component 20 includes a linear polarizer 21, a quarter wave plate 22, a beam splitter 23, and a focusing lens group 24, which are sequentially arranged in a direction away from the display component 10. The linear polarizer 21 is used to modulate the visible light 11 emitted by the display component 10 into a first linear polarized light, the quarter wave plate 22 is used to convert the first linear polarized light into a first circularly polarized light, the beam splitter 23 is used to reflect and modulate the first circularly polarized light into a second circularly polarized light, and the focusing lens group 24 is used to focus the first circularly polarized light and the second circularly polarized light.

[0050] The visible light 11 emitted by the display component 10 is incident on the linear polarizer 21, and the linear polarizer 21 modulates the visible light 11 into a first linear polarized light. The first linear polarized light is incident on the quarter wave plate 22, and the quarter wave plate 22 converts the first linear polarized light into a first circularly polarized light. The first circularly polarized light is incident on the beam splitter 23, and the beam splitter 23 transmits the first circularly polarized light. The first circularly polarized light is refracted by the focusing lens group 24 and incident on the cholesteric liquid crystal element 30. The cholesteric liquid crystal element 30 reflects the first circularly polarized light back to the focusing lens group. The first circularly polarized light reflected by the cholesteric liquid crystal element 30 is refracted by the focusing lens group 24 and enters the beam splitter 23. The beam splitter 23 modulates the first circularly polarized light into a second circularly polarized light and reflects it back to the focusing lens group 24. The focusing lens group 24 refracts the second circularly polarized light and transmits it through the cholesteric liquid crystal element 30, focusing the second circularly polarized light to the human eye, so that the human eye can see the displayed image clearly.

[0051] Alternatively, if Figure 7As shown, in the display device, the positions of the infrared light source 41, the optical metasurface element 43 and the infrared camera 42 in the eye tracking component 40 are also relatively flexible. In some embodiments, the eye tracking component 40 is disposed between the cholesteric liquid crystal element 30 and the focusing lens group 24; or the eye tracking component 40 is disposed between the focusing lens group 24 and the beam splitter 23; or the eye tracking component 40 is disposed between the beam splitter 23 and the quarter wave plate 22; or the eye tracking component 40 is disposed between the quarter wave plate 22 and the linear polarizer 21; or the eye tracking component 40 is disposed between the linear polarizer 21 and the display component 10. In this way, the design and installation of the display device will be more flexible and can be placed according to the actual situation of the AR / VR system.

[0052] In addition, in some embodiments, the infrared light source 41 and the infrared camera 42 do not need to be arranged between two identical elements. For example, when the infrared light source is arranged between the cholesteric liquid crystal element 30 and the focusing lens group 24, the infrared camera can be arranged between the focusing lens group 24 and the beam splitter 23, between the beam splitter 23 and the quarter-wave plate 22, between the quarter-wave plate 22 and the linear polarizer 21, or between the linear polarizer 21 and the display component 10.

[0053] Preferably, if Figure 7 As shown, in some embodiments, the eye tracking component 40 further includes an infrared anti-reflection film 25, which is disposed on a side of the infrared light source 41 and the infrared camera 42 away from the display component. In other words, the infrared anti-reflection film 25 can be disposed on the linear polarizer 21, the quarter-wave plate 22, the beam splitter 23 or the focusing lens group 24. In this way, the infrared anti-reflection film 25 can reduce the reflection of the infrared light 411 by the beam splitter 23, thereby reducing stray light in the display device.

[0054] In particular, in one of the embodiments, the infrared anti-reflection function of the infrared anti-reflection film 25 can also be achieved by designing the film system of the beam splitter 23 to have a structure that can simultaneously achieve visible light semi-transmission and semi-reflection and infrared anti-reflection.

[0055] Furthermore, the present application also provides a near-eye display device, which includes a device body and a display device as described in any one of the above, and the display device is installed on the device body. The device body can recognize an eye diagram containing infrared light spots formed by the display device to realize an eye tracking function. The near-eye display device can recognize the movement of the human eye, so that the near-eye display device can interact according to the movement of the human eye, which is easier and more convenient to use.

[0056] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0057] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A display device, characterized in that: include: A display component, the display component is used to emit visible light; A modulation component, the modulation component is arranged on the light-emitting side of the display component, and is used to modulate the visible light into a first circularly polarized light and reflectively modulate the first circularly polarized light into a second circularly polarized light; A cholesteric liquid crystal element, which is arranged on a side of the modulation component away from the display component, and has a reflection wavelength bandwidth range, and is used to reflect the first circularly polarized light in the corresponding reflection wavelength bandwidth range, and transmit the second circularly polarized light and light in other reflection wavelength bandwidth ranges; as well as An eye tracking component includes an infrared light source disposed between the display component and the cholesteric liquid crystal element and used for emitting infrared light, and an infrared camera disposed between the display component and the cholesteric liquid crystal element and used for receiving the infrared light reflected by the human eye.

2. The display device according to claim 1, characterized in that The cholesteric liquid crystal element comprises a plurality of reflective layers sequentially arranged in a direction away from the display component, wherein the reflective layers have different reflective wavelength bandwidth ranges and are used for respectively reflecting the first circularly polarized light within the corresponding wavelength bandwidth ranges and transmitting the second circularly polarized light and the infrared light.

3. The display device according to claim 2, characterized in that: The reflective layer of the cholesteric liquid crystal element includes a red light reflective layer, a green light reflective layer and a blue light reflective layer arranged in sequence along a direction away from the display component, the red light reflective layer is used to reflect visible light with a central wavelength of red, the green light reflective layer is used to reflect visible light with a central wavelength of green, and the blue light reflective layer is used to reflect visible light with a central wavelength of blue.

4. The display device according to claim 2, characterized in that: The reflective layer includes an orientation layer and a liquid crystal film layer, and the cholesteric liquid crystals in the liquid crystal film layer are arranged along the orientation direction of the orientation layer.

5. The display device according to claim 4, characterized in that: The liquid crystals in the liquid crystal film layer are arranged in a spiral along the normal direction of the alignment layer to form a cholesteric liquid crystal reflection grating.

6. The display device according to any one of claims 1 to 5, characterized in that: The eye tracking component further includes an optical metasurface element, which is arranged on the light-emitting side of the infrared light source.

7. The display device according to any one of claims 1 to 5, characterized in that: The modulation component comprises a linear polarizer, a quarter wave plate, a beam splitter and a focusing lens group which are sequentially arranged in a direction away from the display component.

8. The display device according to claim 7, characterized in that: The eye tracking component is arranged between the cholesteric liquid crystal element and the focusing lens group; or the eye tracking component is arranged between the focusing lens group and the beam splitter; or the eye tracking component is arranged between the beam splitter and the quarter wave plate; or the eye tracking component is arranged between the quarter wave plate and the linear polarizer; or the eye tracking component is arranged between the linear polarizer and the display component.

9. The display device according to claim 7, characterized in that: The eye tracking component further includes an infrared anti-reflection film, which is arranged on a side of the infrared light source and the infrared camera away from the display component.

10. A near-eye display device, characterized in that: include: The display device according to any one of claims 1 to 9; The display device is installed on the device body.

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