Collection device for color correction and near-to-eye display module

Abstract

The invention discloses an acquisition device for color correction and a near-to-eye display module. The acquisition device comprises an image source, a scanning device, a lens and a photoelectric detector, the scanning image surface of the scanning device comprises an image display area and a non-display area, the photoelectric detector for feedback correction is placed between the scanning device and the lens, and the position of the photoelectric detector can just shield a detection signal of the non-display area without influencing an image light signal of the image display area. Therefore, the technical problems that in AR display in the prior art, detection signals provided in a non-display area can be obviously displayed on human eyes and interfere with the human eyes are solved, the interference of the detection signals on the human eyes can be eliminated, and the watching experience of a user is improved.

Description

Technical Field

[0001] The present invention relates to the field of projection display, and in particular to an acquisition device for color correction and a near-eye display module. Background Art

[0002] Fiber laser scanning display is a display method that changes the position of the laser imaging point by swinging the optical fiber. During use, due to problems such as heat dissipation, the output power of the laser light source itself or the coupling efficiency between the light source and the optical fiber will be unstable, further causing the white balance of the display to change, which is a relatively serious problem for the display.

[0003] To ensure the stability of the white balance, it is necessary to detect and correct the power of the laser in real time. As Figure 1 shown, for a general projection display scenario, the non-display area can be used to provide a detection signal to monitor the output optical power of the laser.

[0004] However, when this display source is used for AR (Augmented Reality) display, the detection signal will be clearly visible to the human eye, which makes there always be a flickering error signal in the image observed by the human eye, interfering with the human eye. Summary of the Invention

[0005] The object of the present invention is to provide an acquisition device for color correction and a near-eye display module, which are used to solve the technical problem in the prior art that in AR display, providing a detection signal in the non-display area will be clearly visible to the human eye and interfere with the human eye.

[0006] To achieve the above object of the invention, in the first aspect of the embodiments of the present invention, an acquisition device for color correction is provided. The acquisition device includes an image source, a scanning device, a lens, and a photodetector; the photodetector is located between the scanning image plane of the scanning device and the lens. The scanning image plane of the scanning device includes an image display area and a non-display area, and the position of the photodetector satisfies that the photodetector can receive and block all the detection light signals in the non-display area and will not block the image light signals in the image display area.

[0007] Optionally, when the scanning device scans the image display area, the image source outputs image light signals; when the scanning device scans the non-display area, the image source outputs detection light signals to form a detection area.

[0008] Optionally, in the image plane coordinate system xyz with the center of the detection area as the origin, the position of the photodetector satisfies:

[0009] In the yz plane, the area where the photodetector is located does not exceed a specific plane, which refers to the plane formed by the light rays at the edge of the image display area, and this plane is perpendicular to the yz plane;

[0010] The position of the photodetector in the z direction does not exceed the intersection point of the light rays emitted by the pixels in the display area and the light rays emitted by the pixels in the detection area;

[0011] In the xz plane, the area where the photodetector is located includes all the light rays corresponding to the detection optical signals in the detection area.

[0012] In the second aspect of the embodiments of the present invention, a near-eye display module is provided, which includes the aforementioned acquisition device for color correction and an optical waveguide. The image optical signal is projected onto the corresponding coupling-in area on the optical waveguide and is output through the corresponding coupling-out area on the optical waveguide after being transmitted through the optical waveguide.

[0013] In the third aspect of the embodiments of the present invention, an AR glasses is provided. The AR glasses include a glasses body and at least one group of near-eye display modules as described in the second aspect. The glasses body includes temple arms and a frame. The lens in the frame is a waveguide lens. The scanning device, the lens, and the photodetector are installed in the accommodation cavity of the temple arms; the image source is built in the accommodation cavity, or the image source is designed to be separated from the glasses body.

[0014] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0015] In the solution of the embodiments of the present invention, the scanning image plane of the scanning device includes an image display area and a non-display area. The photodetector for feedback correction is placed between the scanning device and the lens. The position of the photodetector can just block the detection signals in the non-display area without affecting the image optical signals in the image display area, thereby solving the technical problem in the prior art that in AR display, providing detection signals in the non-display area will be clearly visible to the human eye and cause interference to the human eye, and achieving the technical effect of eliminating the interference of the detection signals to the human eye and thus improving the user viewing experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts:

[0017] Figure 1 It is a schematic diagram of a projection display scenario provided for the embodiments of the present invention;

[0018] Figure 2 Schematic diagram of the scanning image plane provided by the embodiment of the present invention;

[0019] Figure 3 Schematic diagram of the light output analysis corresponding to the yz plane provided by the embodiment of the present invention;

[0020] Figure 4 Schematic diagram of the light output analysis corresponding to the xz plane provided by the embodiment of the present invention. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0022] In the embodiment of the present invention, in order to solve the problem that the detection signal will be clearly visible to the human eye, the embodiment of the present invention proposes an arrangement of the acquisition structure for acquiring the output power of the light source without affecting the viewing of the human eye. As Figure 2 shown, the photodetector is placed between the scanning device and the lens. The position of the photodetector can just block the detection signal without affecting the imaging area. In Figure 2 , the upper and lower figures are respectively the top view and the cross-sectional view of the acquisition device. From left to right, they are the scanning device, the scanning image plane of the scanning device, the photodetector, and the lens.

[0023] In the embodiment of the present invention, the position of the photodetector needs to satisfy that it can just block the detection signal without affecting the imaging area, and the position and size of the photodetector need to be accurately calculated.

[0024] As Figure 3 shown, a spatial coordinate system xyz, that is, an image plane coordinate system, is established. The center of the detection area is taken as the coordinate origin O, and the light output is analyzed in the yz plane. To ensure that it does not block the image in the display area, it can be obtained that the area where the photodetector is located shall not exceed the specific plane where the AB line segment is located, and this specific plane is perpendicular to the yz plane. Among them, point A is the edge point of the display area, and point B refers to the intersection point of the light rays emitted by the pixels at the edge of the image display area and the light rays emitted by the pixels located at the center of the detection area. In the z direction, the z-direction coordinate value of the photodetector shall not be greater than point B. Similarly, to ensure that the detection light can be completely blocked, the detector area needs to include all the detection light rays, and this area is the Figure 3 shaded part in. Assuming that the numerical aperture of the lens is NA, then the corresponding θ [rad] = 2sin-1 (NA), θ is the cone angle of the conical light beam emitted by the pixels on the scanned image plane; h' is the distance between the image display edge and the center of the detection area. Through calculation, the coordinates (y B , z B ) of point A in the yz plane are (h', 0), and the coordinates (y B , z B ) of point B in the yz plane are Therefore, the z-direction distance d (i.e., the vertical distance) of the photodetector from the origin needs to satisfy

[0025] Similarly, for the light output analysis in the xz plane, point O tangent to the scanning trajectory in the x direction is as shown in Figure 4 .

[0026] Through analysis, it can be concluded that the area where the detector is located must contain line segment CD. There is a direct relationship between line segment CD and d. Take the radius of curvature of the x-direction scanning trajectory as r, and the total length of the detection area trajectory as l'. Through calculation, the coordinates (x C , z C ) of point C can be obtained:

[0027]

[0028] z C = d

[0029] Similarly, the coordinates (x D , z D ) of point D can be calculated:

[0030]

[0031] z D = d.

[0032] The position and size of the photodetector after precise calculation can meet the above requirements, that is, it can block the detection signal without affecting the imaging area.

[0033] Based on the acquisition device described above, an embodiment of the present invention further provides a near-eye display module. This near-eye display module can be applied to AR glasses. The near-eye display module includes: the aforementioned acquisition device for color correction and an optical waveguide. The image optical signal is projected onto the corresponding coupling-in area on the optical waveguide, so that the image optical signal can be transmitted in the waveguide and coupled out through the corresponding coupling-out area on the optical waveguide and then enter the human eye.

[0034] For an AR glasses, which includes a glasses body and at least one group of near-eye display modules, the glasses body includes temple arms and a frame, the lens in the frame is a waveguide lens, and the scanning device, the lens and the photodetector are installed in the accommodation cavity of the temple arms; the image source can be built in the accommodation cavity or can be designed to be separated from the glasses body.

[0035] All features disclosed in this specification, or steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way.

[0036] Any feature disclosed in this specification (including any additional claims, abstract and drawings), unless specifically stated, can be replaced by other equivalent or similar-purpose alternative features. That is, unless specifically stated, each feature is only an example of a series of equivalent or similar features.

[0037] The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, as well as steps of any new method or process disclosed or any new combination.

Claims

1. An acquisition device for color correction, characterized in that, the acquisition device includes an image source, a scanning device, a lens, and a photodetector; the photodetector is located between the scanning image plane of the scanning device and the lens, the scanning image plane includes an image display area and a non-display area, and the position of the photodetector satisfies: the photodetector can receive and block all detection optical signals in the non-display area, and does not block the image optical signals in the image display area.

2. The device according to claim 1, characterized in that, when the scanning device scans the image display area, the image source outputs image optical signals; when the scanning device scans the non-display area, the image source outputs detection optical signals to form a detection area.

3. The acquisition device according to claim 1, characterized in that, in the image plane coordinate system xyz established with the center of the detection area as the origin, the position of the photodetector satisfies: in the yz plane, the area where the photodetector is located does not exceed a specific plane, and the specific plane refers to the plane formed by the edge light rays of the display area, and the plane is perpendicular to the yz plane; the z-direction position of the photodetector does not exceed the intersection point of the light rays emitted by the pixels in the image display area and the light rays emitted by the pixels in the detection area; in the xz plane, the area where the photodetector is located includes all the light rays corresponding to the detection optical signals in the detection area.

4. A near-eye display module, characterized in that, it includes the acquisition device according to any one of claims 1-3 and an optical waveguide, and the image optical signals are projected onto the corresponding coupling-in area on the optical waveguide and output through the corresponding coupling-out area on the optical waveguide after being transmitted through the optical waveguide.

5. An AR glasses, characterized in that, the AR glasses include a glasses body and at least one group of near-eye display modules according to claim 4, the glasses body includes temple arms and a frame, the lens in the frame is a waveguide lens, and the scanning device, the lens, and the photodetector are installed in the accommodation cavity of the temple arms; the image source is built in the accommodation cavity, or the image source is designed separately from the glasses body.

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