Image acquisition system, image acquisition method thereof and near-to-eye display glasses

Abstract

The invention provides an image acquisition system, an image acquisition method thereof and near-to-eye display glasses, and relates to the field of near-to-eye display. In use, first imaging light from the eye side is reflected through the first coupling input optical element; transmitting the first imaging light or reflecting a second imaging light originating from the non-eye side through a second coupling input optical element; reflecting the first imaging light or the second imaging light through a coupling output optical element; therefore, different imaging light rays are transmitted to a camera sensor along corresponding optical paths, and corresponding target images are generated. On the basis, only a single camera sensor is utilized, and a reasonable optical path is designed, so that different image acquisition functions are ingeniously realized, the hardware design is simplified, and the requirement of light weight of the glasses is met.

Description

Technical Field

[0001] The present invention relates to the field of near-eye display, and in particular to an image acquisition system and an image acquisition method thereof and near-eye display glasses. Background Art

[0002] Near-eye display technology is an important technical support for realizing virtual reality (VR) and augmented reality (AR) experiences in the future. In recent years, it has received widespread attention and rapid development in both industry and academia.

[0003] At present, image acquisition technology has been widely used in near-eye display glasses. In summary: usually according to actual needs, imaging light from different directions is transmitted to corresponding camera sensors along respective preset optical paths inside the optical waveguide to generate corresponding target images respectively. However, since multiple camera sensors need to be set up, the glasses become bulky and the design cost increases. In view of this, it is necessary to provide a new image acquisition technology. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the present invention provides an image acquisition system and an image acquisition method thereof and near-eye display glasses, which solve the technical problems of needing to set up multiple camera sensors, resulting in bulky glasses and increased design costs.

[0006] (II) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] An image acquisition system, based on a geometric light waveguide lens, comprises a first coupling input optical element, a second coupling input optical element, a coupling output optical element and a camera sensor;

[0009] The first coupling-in optical element, the second coupling-in optical element, and the coupling-out optical element are all embedded in the geometric light waveguide lens, and the second coupling-in optical element is located between the first coupling-in optical element and the coupling-out optical element;

[0010] The camera sensor faces the geometric light waveguide lens and is close to the coupling output optical element;

[0011] Wherein, the incident area of ​​the first imaging light from the eye side on the geometrical light waveguide lens, the first coupling-in optical element, the second coupling-in optical element, the coupling-out optical element and the camera sensor constitute a first optical path;

[0012] The incident area of ​​the second imaging light from the non-eye side on the geometrical light waveguide lens, the second coupling-in optical element, the coupling-out optical element and the camera sensor constitute a second optical path.

[0013] Preferably, the first coupling input optical element is a first semi-transparent and semi-reflective coating.

[0014] Preferably, the first semi-transparent and semi-reflective coating is a first free-curved surface, and the opening direction is toward the eye side.

[0015] Preferably, the second coupling input optical element is a second semi-transmissive and semi-reflective coating.

[0016] Preferably, the second semi-transparent and semi-reflective coating is a second free-curved surface, and the opening direction faces the non-eye side.

[0017] Preferably, the coupling-out optical element is a total reflection coating.

[0018] Preferably, the total reflection coating is a planar coating.

[0019] An image acquisition method of the image acquisition system as described above, comprising:

[0020] The first imaging light originating from the eye side is reflected by the first coupling-in optical element and transmitted to the second coupling-in optical element along the first optical path;

[0021] The first imaging light is transmitted through the second coupling-in optical element and transmitted to the coupling-out optical element along the first optical path; or the second imaging light originating from the non-eye side is reflected through the second coupling-in optical element and transmitted to the coupling-out optical element along the second optical path;

[0022] Reflecting the first imaging light or the second imaging light through the coupling output optical element, and transmitting the light to the camera sensor along the first optical path or the second optical path accordingly;

[0023] After the camera sensor collects the first imaging light or the second imaging light, it generates a corresponding target image.

[0024] A pair of near-eye display glasses comprises the image acquisition system as described above.

[0025] Preferably, the camera sensor is located at an edge of a frame of the near-eye display glasses.

[0026] (III) Beneficial effects

[0027] The present invention provides an image acquisition system and an image acquisition method thereof and near-eye display glasses, which solve the problem of needing to set up multiple camera sensors. Compared with the prior art, it has the following advantages:

[0028] Beneficial effects:

[0029] The present invention is based on a geometric light waveguide lens, and includes a first coupling input optical element, a second coupling input optical element, a coupling output optical element, and a camera sensor. When in use, the first imaging light originating from the eye side is reflected by the first coupling input optical element; the first imaging light is transmitted or the second imaging light originating from the non-eye side is reflected by the second coupling input optical element; the first imaging light or the second imaging light is reflected by the coupling output optical element. This enables different imaging lights to be transmitted to the camera sensor along the corresponding optical path to generate the corresponding target image. Based on this, by using only a single camera sensor and designing a reasonable optical path, different image acquisition functions can be cleverly realized, simplifying the hardware design and meeting the lightweight requirements of glasses. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of the structure of a first image acquisition system provided by an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of the structure of a second image acquisition system provided by an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of the structure of a third image acquisition system provided by an embodiment of the present invention;

[0034] Figure 4 A flowchart of an image acquisition method of an image acquisition system provided by an embodiment of the present invention;

[0035] Figure 5 A partial schematic diagram of near-eye display glasses provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] The embodiments of the present application provide an image acquisition system and an image acquisition method thereof and near-eye display glasses, thereby solving the technical problem of needing to set up multiple camera sensors, resulting in bulky glasses and increased design costs. The embodiments of the present application simplify the hardware design and meet the requirements for lightweight glasses, as well as the requirements for beautiful and simple design.

[0038] The technical solution in the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows:

[0039] In some possible situations, for example, the eye image acquisition function for the purpose of judging fatigue status or iris ID recognition; another example is the eye tracking function achieved by light spot reflection positioning, crystal laser scanning (i.e. capturing the pupil black spot position) or retinal physiological characteristics imaging. At this time, the image acquisition technology applied to near-eye display glasses needs to collect the first imaging light from the eye side. Among them, the eye side refers to the side of the geometric light waveguide lens close to the user's eye.

[0040] In other possible situations, for example, the SLAM (Simultaneous Localization And Mapping) gesture interaction function is realized by capturing gesture images; another example is the RGB image acquisition function developed to meet the needs of daily photography or photography. At this time, the image acquisition technology applied to near-eye display glasses needs to collect the second imaging light from the non-eye side. The non-eye side refers to the side of the geometric light waveguide lens away from the user's eyes.

[0041] Therefore, it is of great significance to design a single camera to realize different image acquisition functions of near-eye display glasses. Accordingly, the image acquisition system provided by the embodiment of the present invention is based on a geometric light waveguide lens, including a first coupling input optical element, a second coupling input optical element, a coupling output optical element and a camera sensor.

[0042] When in use, the first imaging light from the eye side is reflected by the first coupling input optical element; the first imaging light is transmitted or the second imaging light from the non-eye side is reflected by the second coupling input optical element; the first imaging light or the second imaging light is reflected by the coupling output optical element. In this way, different imaging lights are transmitted to the camera sensor along the corresponding optical path to generate the corresponding target image.

[0043] Based on this, by using only a single camera sensor and designing a reasonable optical path, different image acquisition functions can be cleverly implemented, simplifying the hardware design and meeting the lightweight requirements of glasses.

[0044] In particular, the provided image acquisition system can be applied to but not limited to near-eye display glasses such as VR / AR. The camera sensor can be located at the edge of the frame of the near-eye display glasses, that is, the camera sensor is moved out of the eye's visual area. This hidden design meets the design requirements of beautiful and simple glasses.

[0045] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0046] Embodiment 1:

[0047] like Figure 1 As shown, an embodiment of the present invention provides an image acquisition system based on a geometric light waveguide lens, comprising a first coupling input optical element, a second coupling input optical element, a coupling output optical element and a camera sensor.

[0048] The first coupling-in optical element, the second coupling-in optical element and the coupling-out optical element are all embedded in the geometrical light waveguide lens, and the second coupling-in optical element is located between the first coupling-in optical element and the coupling-out optical element.

[0049] The camera sensor faces the geometric light waveguide lens and is close to the coupling output optical element;

[0050] Wherein, the incident area of ​​the first imaging light from the eye side on the geometrical light waveguide lens, the first coupling-in optical element, the second coupling-in optical element, the coupling-out optical element and the camera sensor constitute a first optical path;

[0051] The incident area of ​​the second imaging light from the non-eye side on the geometrical light waveguide lens, the second coupling-in optical element, the coupling-out optical element and the camera sensor constitute a second optical path.

[0052] Specifically:

[0053] When the first imaging light from the eye side needs to be collected, Figure 1 The first optical path shown by the solid arrow corresponds to:

[0054] First, the first imaging light is reflected to the second coupling input optical element through the first coupling input optical element; secondly, the first imaging light is transmitted to the coupling output optical element through the second coupling input optical element; thirdly, the first imaging light is reflected to the camera sensor through the coupling output optical element; finally, the camera sensor collects the first imaging light to generate a corresponding target image.

[0055] When it is necessary to collect the second imaging light from the non-eye side, Figure 1 The second optical path shown by the dashed arrow corresponds to:

[0056] First, the second imaging light is reflected to the coupling output optical element through the second coupling input optical element; secondly, the second imaging light is reflected to the camera sensor through the coupling output optical element; finally, the camera sensor collects the second imaging light to generate a corresponding target image.

[0057] visible, Figure 1 The two partially overlapping optical paths in the design do not interfere with each other and can form independent images. Based on this, the embodiment of the present invention only uses a single camera sensor and cleverly implements different image acquisition functions by designing the first and second optical paths, thereby simplifying the hardware design and meeting the lightweight requirements of the glasses.

[0058] In an optional embodiment, the first coupling input optical element is a first semi-transparent and semi-reflective coating; the first semi-transparent and semi-reflective coating is a first free-form surface, and the opening direction is toward the eye side. Thus, the field of view is increased in the geometric light waveguide lens with limited volume, so as to expand the field of view of the camera sensor when collecting the first imaging light.

[0059] In an optional embodiment, the second coupling input optical element is a second semi-transparent and semi-reflective coating. Since the transmittance and reflectance of the second semi-transparent and semi-reflective coating are 50% each, it can simultaneously transmit the first imaging light and reflect the second imaging light.

[0060] The second semi-transparent and semi-reflective coating is a second free-form surface, and the opening direction is toward the non-eye side. Thus, the field of view is increased in the geometric light waveguide lens with limited volume, so as to expand the field of view of the camera sensor when collecting the second imaging light.

[0061] In an optional implementation, the coupling-out optical element is a total reflection coating.

[0062] Since the coupling output optical element is close to the camera sensor, it can be considered that there is no need to increase the field of view in theory. Therefore, the total reflection coating can be directly selected as a flat coating.

[0063] Furthermore, it is understood that:

[0064] First, the embodiments of the present invention do not limit the mutual positional relationship between the above-mentioned coupling input optical element, the second coupling input optical element, the coupling output optical element, the camera sensor and the geometric light waveguide lens. Instead, it should be understood that all possible mutual positional relationship combinations that meet the above-mentioned functional requirements fall within the protection scope required by the embodiments of the present invention.

[0065] For example, Figure 1 The whole is flipped vertically to obtain Figure 2 The image acquisition system shown is one of the reasonable variations of the embodiment of the present invention.

[0066] For example, Figure 1 The coupled output optical element and camera sensor in the image are flipped horizontally to obtain Figure 3 The image acquisition system shown is also one of the reasonable variations of the embodiment of the present invention.

[0067] Second, for different image acquisition functions of near-eye display glasses, the corresponding camera sensor selection criteria are usually inconsistent. At this point, those skilled in the art should know that the embodiment of the present invention requires the selection of a camera sensor type that can take into account all image acquisition functions.

[0068] For example, the image acquisition system provided is specifically used to simultaneously realize the eye tracking function by positioning the infrared light spot reflected by the cornea, the SLAM gesture interaction function by capturing gesture images, and the RGB image acquisition function developed to meet daily photo or photography needs.

[0069] Among them, the eye tracking function requires the camera sensor to have an operating wavelength of 850nm and 160,000 pixels; the SLAM gesture interaction function requires the camera sensor to have an operating wavelength of 850nm and more than 3 million pixels; the RGB image acquisition function requires the camera sensor to have an operating wavelength of 380nm to 780nm (visible light), and the number of pixels depends on the requirements. At this time, it is necessary to take into account the above three requirements and select the appropriate camera sensor type (in fact, the existing sensor technology can also meet the combination of the above parameters).

[0070] Embodiment 2:

[0071] like Figure 4 As shown, the embodiment of the present invention provides an image acquisition method of the image acquisition system as described in Embodiment 1, comprising:

[0072] reflecting the first imaging light from the eye side through the first coupling-in optical element and transmitting the first imaging light along the first optical path to the second coupling-in optical element;

[0073] The first imaging light is transmitted through the second coupling-in optical element and transmitted to the coupling-out optical element along the first optical path; or the second imaging light originating from the non-eye side is reflected through the second coupling-in optical element and transmitted to the coupling-out optical element along the second optical path;

[0074] Reflecting the first imaging light or the second imaging light through the coupling output optical element, and transmitting the light to the camera sensor along the first optical path or the second optical path accordingly;

[0075] After the camera sensor collects the first imaging light or the second imaging light, it generates a corresponding target image.

[0076] Embodiment 3:

[0077] An embodiment of the present invention provides a near-eye display glasses, comprising the image acquisition system as described in Example 1.

[0078] In an optional embodiment, if Figure 5 As shown, the camera sensor can be designed to be located at the edge of the frame of the near-eye display glasses. By moving the camera sensor out of the eye's visual area, the hidden design meets the design requirements of the glasses for beauty and simplicity.

[0079] It is not difficult to understand that since Examples 2 to 3 all include the image acquisition system in Example 1, the explanations, examples and beneficial effects of the relevant contents can refer to the corresponding parts in the image acquisition system and will not be repeated here.

[0080] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0081] 1. The embodiment of the present invention is based on a geometric light waveguide lens, including a first coupling input optical element, a second coupling input optical element, a coupling output optical element and a camera sensor. When in use, the first imaging light originating from the eye side is reflected by the first coupling input optical element; the first imaging light is transmitted or the second imaging light originating from the non-eye side is reflected by the second coupling input optical element; the first imaging light or the second imaging light is reflected by the coupling output optical element. In this way, different imaging lights are transmitted to the camera sensor along the corresponding optical path to generate the corresponding target image. Based on this, only a single camera sensor is used, and by designing a reasonable optical path, different image acquisition functions can be cleverly realized, which simplifies the hardware design and meets the lightweight requirements of glasses.

[0082] 2. The image acquisition system provided in the embodiment of the present invention can be applied to but not limited to near-eye display glasses such as VR / AR. The camera sensor can be located at the edge of the frame of the near-eye display glasses, that is, the camera sensor is moved out of the eye's visual area. This hidden design meets the design requirements of beautiful and simple glasses.

[0083] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0084] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An image acquisition system, characterized in that: Based on a geometric light waveguide lens, it includes a first coupling input optical element, a second coupling input optical element, a coupling output optical element and a camera sensor; The first coupling-in optical element, the second coupling-in optical element, and the coupling-out optical element are all embedded in the geometric light waveguide lens, and the second coupling-in optical element is located between the first coupling-in optical element and the coupling-out optical element; The camera sensor faces the geometric light waveguide lens and is close to the coupling output optical element; Wherein, the incident area of ​​the first imaging light from the eye side on the geometrical light waveguide lens, the first coupling-in optical element, the second coupling-in optical element, the coupling-out optical element and the camera sensor constitute a first optical path; The incident area of ​​the second imaging light originating from the non-eye side on the geometrical light waveguide lens, the second coupling-in optical element, the coupling-out optical element and the camera sensor constitute a second optical path.

2. The image acquisition system according to claim 1, characterized in that: The first coupling input optical element is a first semi-transmissive and semi-reflective coating.

3. The image acquisition system according to claim 2, characterized in that: The first semi-transmissive and semi-reflective coating is a first free-curved surface, and the opening direction faces the eye side.

4. The image acquisition system according to claim 1, characterized in that: The second coupling input optical element is a second semi-transmissive and semi-reflective coating.

5. The image acquisition system according to claim 4, characterized in that: The second semi-transmissive and semi-reflective coating is a second free-curved surface, and the opening direction faces the non-eye side.

6. The image acquisition system according to claim 1, characterized in that: The coupling output optical element is a total reflection coating.

7. The image acquisition system according to claim 6, characterized in that: The total reflection coating is a planar coating.

8. An image acquisition method according to any one of claims 1 to 7, characterized in that: include: The first imaging light originating from the eye side is reflected by the first coupling-in optical element and transmitted to the second coupling-in optical element along the first optical path; The first imaging light is transmitted through the second coupling-in optical element and transmitted along the first optical path to the coupling-out optical element; or reflecting the second imaging light originating from the non-eye side through the second coupling-in optical element and transmitting the second imaging light along the second optical path to the coupling-out optical element; Reflecting the first imaging light or the second imaging light through the coupling output optical element, and transmitting the light to the camera sensor along the first optical path or the second optical path accordingly; After the camera sensor collects the first imaging light or the second imaging light, it generates a corresponding target image.

9. A near-eye display glasses, characterized in that: It comprises the image acquisition system as claimed in any one of claims 1 to 7.

10. The near-eye display glasses according to claim 9, characterized in that: The camera sensor is located at the edge of the frame of the near-eye display glasses.

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