Camera module applied to eyeball tracking, manufacturing method thereof and head-mounted device

Abstract

The invention discloses a camera module applied to eyeball tracking, a manufacturing method of the camera module and head-mounted equipment. The camera module applied to eyeball tracking is installed on a head-mounted device, and the camera module comprises an optical lens which faces an eyeball of a user of the head-mounted device and receives detection light reflected by the eyeball; the photosensitive chip is positioned on the image side of the optical lens and is used for imaging the detection light projected to the photosensitive chip through the optical lens; wherein the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip. By optimizing the structure of the camera module, the effect of the image shot by the camera module in a microspur and inclined manner can be optimized, so that the accuracy of eyeball recognition and tracking through the image can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of smart device technology, and in particular to a camera module for eye tracking, a manufacturing method thereof, and a head-mounted device. Background Art

[0002] At present, the eye tracking technology used in augmented reality (AR) and virtual reality (VR) devices mainly projects infrared detection light to the eyeballs of the device user through an infrared light source, and shoots the user's eyeballs through an infrared camera module to confirm the visual axis direction of the eyeball through the center of the pupil in the image. Limited by the structure and volume of AR and VR head-mounted display devices, the infrared camera module is usually installed at the nose pads or the side of the eyes of AR and VR head-mounted display devices, so the infrared camera module shoots the eyeballs in macro and oblique shots.

[0003] However, macro and tilted shooting will affect the effect of the image captured by the infrared camera module, thereby affecting the accuracy of eye recognition and tracking through the image. Summary of the invention

[0004] The camera module for eye tracking, the manufacturing method thereof, and the head-mounted device provided in the embodiments of the present application can solve or partially solve the above-mentioned deficiencies in the prior art or other deficiencies in the prior art.

[0005] According to the first aspect of the present application, a camera module for eye tracking is provided, which is installed on a head-mounted device. The camera module includes: an optical lens facing the eyeball of a user of the head-mounted device, receiving detection light reflected by the eyeball; and a photosensitive chip, located on the image side of the optical lens, imaging the detection light projected to the photosensitive chip through the optical lens; wherein the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

[0006] In one embodiment of the present application, there is a first inclination angle between the lens plane of the optical lens and the eyeball plane of the eyeball; when the lens plane of the optical lens is parallel to the photosensitive surface, the optical center of the optical lens is offset from the center of the photosensitive surface by a first distance so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

[0007] In one embodiment of the present application, the first distance is determined according to the first inclination angle and the size of the photosensitive surface.

[0008] In one embodiment of the present application, the first inclination angle is between 0° and 15°, and the first distance is between 120um and 200um.

[0009] In one embodiment of the present application, the first inclination angle is 7°, and the first distance is 150 um.

[0010] In one embodiment of the present application, the head-mounted device includes a virtual reality head-mounted display device, and the camera module is installed at the nose pad or the side of the eye of the virtual reality head-mounted display device.

[0011] In one embodiment of the present application, there is a second inclination angle between the lens plane of the optical lens and the eyeball plane of the eyeball; there is a non-zero first angle between the lens plane of the optical lens and the photosensitive surface, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip; wherein the photosensitive surface, the lens plane and the eyeball plane intersect in a straight line.

[0012] In one embodiment of the present application, the first angle is determined according to the second inclination angle and parameters of the optical lens.

[0013] In one embodiment of the present application, the second inclination angle is between 15° and 75°, and the first angle is between 3.5° and 10°.

[0014] In one embodiment of the present application, the second inclination angle is 46°, and the first included angle is 3.7°.

[0015] In one embodiment of the present application, there is a third inclination angle between the lens plane of the optical lens and the eyeball plane of the eyeball; the optical center of the optical lens is offset from the center of the photosensitive surface by a second distance, and there is a non-zero second angle between the lens plane of the optical lens and the photosensitive surface, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip; wherein the photosensitive surface, the lens plane and the eyeball plane intersect in a straight line.

[0016] In one embodiment of the present application, the second distance is determined according to the third inclination angle and the size of the photosensitive surface; the second angle is determined according to the third inclination angle, the second distance and parameters of the optical lens.

[0017] In one embodiment of the present application, the third inclination angle is between 15° and 75°, the second distance is between 50um and 120um, and the second angle is between 1° and 3.5°.

[0018] In one embodiment of the present application, the third inclination angle is 39°, the second distance is 100 um, and the second angle is 3°.

[0019] In one embodiment of the present application, the head-mounted device includes an augmented reality head-mounted display device, and the camera module is installed at the nose pad or the side of the eye of the augmented reality head-mounted display device.

[0020] According to the second aspect of the present application, a method for manufacturing a camera module for eye tracking is provided, wherein the camera module is installed on a head-mounted device, and the manufacturing method comprises: processing an optical lens array with a non-zero preset inclination angle on a glass wafer based on a semiconductor manufacturing process; cutting the optical lens array to obtain a single optical lens with the preset inclination angle; and for each optical lens with the preset inclination angle, assembling it with a photosensitive chip based on an active alignment process to obtain a camera module with the preset inclination angle as an included angle between the lens plane of the optical lens and the photosensitive surface of the photosensitive chip, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

[0021] In one embodiment of the present application, an optical lens array having a non-zero preset inclination angle is processed on a glass wafer based on a semiconductor manufacturing process, comprising: processing a first optical lens array having the preset inclination angle on a first glass wafer based on a semiconductor manufacturing process; processing a second optical lens array having the preset inclination angle on a second glass wafer based on a semiconductor manufacturing process; and splicing the first optical lens array and the second optical lens array based on alignment of a single first optical lens and a single second optical lens to obtain the optical lens array having the preset inclination angle.

[0022] According to a third aspect of the present application, a head-mounted device is provided, comprising: a device body; and a camera module for eye tracking according to the first aspect, wherein the camera module is installed on the device body.

[0023] According to the camera module used for eye tracking, its manufacturing method and head-mounted device provided in the embodiments of the present application, by making the optical center of the optical lens deviate from the center of the photosensitive surface of the photosensitive chip and optimizing the structure of the camera module based on the principle of axis-shift optics, the effect of the image taken at macro and tilt by the camera module can be optimized, thereby improving the accuracy of eye recognition and tracking through images.

[0024] The content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other features, purposes and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments made with reference to the following drawings. The drawings are used to better understand the present solution and do not constitute a limitation of the present application. Among them:

[0026] Figure 1 A schematic diagram of the positional relationship between a camera module used for eye tracking in an existing head-mounted display device and a human eye;

[0027] Figure 2 is a schematic structural diagram of a camera module applied to eye tracking according to an embodiment of the present application;

[0028] Figure 3 is a structural schematic diagram of a camera module applied to eye tracking according to another embodiment of the present application;

[0029] Figure 4 is a flow chart of a method for manufacturing a camera module for eye tracking according to an embodiment of the present application;

[0030] Figure 5 A flow chart of processing an optical lens array on a glass wafer according to an embodiment of the present application;

[0031] Figure 6 The present invention is a process flow chart for processing and cutting a glass wafer to obtain a single optical lens according to an embodiment of the present application. DETAILED DESCRIPTION

[0032] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0033] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0034] At present, in augmented reality (AR) and virtual reality (VR) head-mounted display devices, the eye tracking technology is mainly used to detect the line of sight of the human eye, so as to adjust the display position of the virtual image according to the line of sight of the human eye to ensure that the human eye can observe the virtual image. The eye tracking technology used in AR and VR head-mounted display devices mainly projects infrared detection light to the eyeballs of the device user through an infrared light source, and photographs the user's eyeballs through an infrared camera module to confirm the direction of the eye's visual axis through the center of the pupil in the image. Due to the structure and volume of AR and VR head-mounted display devices, the infrared camera module is usually installed on the nose pads or the sides of the eyes of the AR and VR head-mounted display devices, so the infrared camera module shoots the eyeballs in macro and oblique shots. Such as Figure 1 As shown, the infrared camera module 100 is installed at the nose pad of the AR or VR head-mounted display device (not shown), the distance d between the infrared camera module 100 and the eyeball 200 of the user of the AR or VR head-mounted display device (not shown) is about 3.5 cm, and the inclination angle β between the infrared camera module 100 and the eyeball 200 of the user of the AR or VR head-mounted display device (not shown) is about 25°.

[0035] In a conventional camera module, such as the infrared camera module 100, the lens plane of the optical lens is parallel to the photosensitive surface of the photosensitive chip, and the optical center of the optical lens is aligned with the center of the photosensitive surface, and the focal plane of the optical lens is parallel to the lens plane and the photosensitive surface. Figure 1 As shown, when macro and tilted shooting is performed, the eyeball plane 211 of the eyeball 200 is not parallel to the lens plane and photosensitive surface of the optical lens of the infrared camera module 100, that is, there is an inclination angle β, so that the focal plane of the optical lens of the infrared camera module 100 does not overlap with the eyeball plane 211 of the eyeball 200, that is, there is an inclination angle β. In this case, the image captured by the infrared camera module 100 will have the problem of too narrow image depth of field, which will cause the image to be out of focus and the edge field of view blurred. At the same time, the image captured by the infrared camera module 100 at an angle will also have the problem of image perspective deformation, which will cause the image to present a deformation effect of being larger at the bottom and smaller at the top. Therefore, macro and tilted shooting will affect the effect of the image captured by the infrared camera module 100, thereby affecting the accuracy of eye recognition and tracking through images.

[0036] In order to solve the above problems, an embodiment of the present application provides a camera module 300 for eye tracking.

[0037] Figure 2 Schematic diagram of the structure of a camera module 300 used for eye tracking according to an embodiment of the present application. Figure 3FIG. 3 is a schematic diagram of the structure of a camera module 300 for eye tracking according to another embodiment of the present application. The camera module 300 for eye tracking in the embodiment of the present application is installed in a head-mounted device, such as an AR and VR head-mounted display device, etc., and the embodiment of the present application is not limited to this. Figure 2 and Figure 3 As shown, the camera module 300 for eye tracking of the embodiment of the present application may include: an optical lens 310 and a photosensitive chip 320. The optical lens 310 faces the eyeball of the user of the head-mounted device and receives the detection light reflected by the eyeball. The photosensitive chip 320 is located on the image side of the optical lens 310 and images the detection light projected to the photosensitive chip 320 through the optical lens 310, wherein the optical center O of the optical lens 310 deviates from the center O' of the photosensitive surface 321 of the photosensitive chip 320. The optical center O of the optical lens 310 may be deviated from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by making a preset non-zero angle between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320, and / or by making the optical center O of the optical lens 310 offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by a preset distance.

[0038] The camera module 300 for eye tracking provided in the embodiment of the present application can optimize the effect of the image taken at a macro and tilted position by the camera module 300, expand the depth of field of the image taken at a macro and tilted position by the camera module 300, obtain a clear image, and / or improve the perspective deformation problem of the image taken at an angle by the camera module 300, avoid the deformation effect of the image being larger at the bottom and smaller at the top, thereby improving the accuracy of eye recognition and tracking through images.

[0039] It should be understood that the embodiments of the present application do not limit the composition and implementation of the optical lens 310, and the number and type of optical lenses included in the optical lens 310 can be determined according to the accuracy requirements of eye tracking, etc. For example, the optical lens 310 can include two optical lenses, one is a plano-convex lens, and the other is a concave-convex lens. The optical lenses can also be coated with an optical film with specific functions. The optical lens 310 can be manufactured using a semiconductor manufacturing process and is a wafer-level optical element (Wafer Level Optics, referred to as WLO).

[0040] It should be understood that the embodiment of the present application does not limit the type of the photosensitive chip 320, and the type of the photosensitive chip 320 can be determined according to the accuracy requirements of eye tracking, etc. For example, the photosensitive chip 320 can be a charge coupled device (CCD) chip, or a complementary metal-oxide semiconductor (CMOS) chip.

[0041] It should be understood that the camera module 300 in the embodiments of the present application refers to a device that has an imaging function for light in the infrared band, and it may include but is not limited to a camera, a camcorder, a camera, a photographic module, a camera module, etc.

[0042] In some embodiments of the present application, Figure 2 As shown, in the camera module 300, there is a non-zero first angle α1 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320, there is a first inclination angle β1 between the lens plane 311 of the optical lens 310 and the focal plane 312, and the photosensitive surface 321, the lens plane 311 and the focal plane 312 intersect at a straight line a. In this embodiment, the optical center O of the optical lens 310 is deviated from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by making the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 have a non-zero first angle α1. When the camera module 300 is installed on the head-mounted device, the first inclination angle β1 is the inclination angle between the camera module 300 and the eyeball of the user of the head-mounted device, and is also the inclination angle between the lens plane 311 of the optical lens 310 and the eyeball plane of the eyeball of the user of the head-mounted device. At this time, the photosensitive surface 321, the lens plane 311 and the eyeball plane intersect at the straight line a.

[0043] In this embodiment, the optical lens 310 and the photosensitive chip 320 are assembled in such a way that a non-zero first angle α1 is formed between the lens plane 311 and the photosensitive surface 321, so as to obtain a camera module 300 in which the optical center O of the optical lens 310 deviates from the center O' of the photosensitive surface of the photosensitive chip 320. When the camera module 300 is installed on the head-mounted device at the first inclination angle β1, the focal plane 312 of the optical lens 310 can be made to coincide with the eyeball plane of the eyeball of the user of the head-mounted device based on the principle of axis-shift optics. Thus, the depth of field of the image taken at a macro distance and at an angle by the camera module 300 can be changed from a front-to-back relationship to a left-to-right relationship, thereby expanding the depth of field of the image taken at a macro distance and at an angle by the camera module 300, and thereby obtaining an overall clear image including the edge field of view.

[0044] Optionally, in the camera module 300, the size of the first angle α1 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 can be determined according to the size of the first inclination angle β1 of the camera module 300 installed on the head mounted device and the parameters of the optical lens 310. For example, the parameters of the optical lens 310 may include the effective focal length of the optical lens 310, the field of view of the optical lens 310, etc., which is not limited in the embodiments of the present application.

[0045] Optionally, the first inclination angle β1 of the camera module 300 installed on the head mounted device may be between 15° and 75°, and the first angle α1 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 may be between 3.5° and 10°. In an optional example, the distance between the camera module 300 and the eyeball of the user of the head mounted device is 13 mm, the first inclination angle β1 of the camera module 300 installed on the head mounted device is 46°, and the first angle α1 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 is 3.7°, as shown in FIG. Figure 2 As shown, the focal plane 312 of the optical lens 310 of the camera module 300 forms an angle of 46° with the lens plane 311 and coincides with the eyeball plane of the eyeball of the user of the head mounted device.

[0046] Optionally, due to Figure 2 The camera module 300 shown in the figure optimizes the structure of the camera module 300 by changing the angle between the optical lens 310 and the photosensitive chip 320, thereby optimizing the effect of the image captured by the camera module 300 at a macro distance and at an angle. Figure 2 The camera module 300 shown is relatively small in size and can be applied to head-mounted devices with a small installation space, such as augmented reality glasses. Figure 2 The camera module 300 shown can be installed at the nose pad of the augmented reality glasses. In another optional example, Figure 2 The camera module 300 shown can be installed on the side of the eye of the augmented reality glasses.

[0047] In other embodiments of the present application, Figure 3As shown, in the camera module 300, the lens plane 311 of the optical lens 310 is parallel to the photosensitive surface 321 of the photosensitive chip 320, the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by a first distance d1, and the lens plane 311 of the optical lens 310 is parallel to the focal plane 312. In this embodiment, when the lens plane 311 of the optical lens 310 is parallel to the photosensitive surface 321 of the photosensitive chip 320, the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by a first distance d1. When the camera module 300 is installed on the head-mounted device, the camera module 300 can have a very small second inclination angle β2 (not shown) between the camera module 300 and the eyeball of the user of the head-mounted device. The second inclination angle β2 is also the inclination angle between the lens plane 311 of the optical lens 310 and the eyeball plane of the eyeball of the user of the head-mounted device. At this time, the photosensitive surface 321 and the lens plane 311 are almost parallel to the eyeball plane.

[0048] In this embodiment, the optical lens 310 and the photosensitive chip 320 are assembled in such a way that the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 by a first distance d1, thereby obtaining a camera module 300 in which the optical center O of the optical lens 310 deviates from the center O' of the photosensitive surface 321 of the photosensitive chip 320. When the camera module 300 is mounted on the head mounted device at a very small second tilt angle β2, the camera module 300 can be placed in a state of almost non-tilted shooting based on the principle of axis-shift optics, and the entire eyeball of the user of the head mounted device can be imaged on the photosensitive surface 321 of the photosensitive chip 320, thereby improving the perspective deformation problem of the image taken by the camera module 300 at an angle, avoiding the deformation effect of the image being larger at the bottom and smaller at the top, and at the same time, the camera module 300 does not need to be assembled at an angle, which can reduce the difficulty of assembling the camera module 30.

[0049] Optionally, in the camera module 300, the first distance d1 of the optical center O of the optical lens 310 offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 can be determined according to the size of the second inclination angle β2 of the camera module 300 installed on the head mounted device and the size of the photosensitive surface 321 of the photosensitive chip 320. The first distance d1 can be obtained by directional offsetting the optical center O of the optical lens 310 from the center O' of the photosensitive surface 321 along the long side or short side of the photosensitive surface 321.

[0050] Optionally, the second inclination angle β2 of the camera module 300 installed on the head-mounted device can be between 0° and 15°, and the first distance d1 of the optical center O of the optical lens 310 offsetting the center O' of the photosensitive surface 321 of the photosensitive chip 320 can be between 120um and 200um. In an optional example, the second inclination angle β2 of the camera module 300 installed on the head-mounted device is 7°, the first distance d1 of the optical center O of the optical lens 310 offsetting the center O' of the photosensitive surface 321 of the photosensitive chip 320 is 150um, and the center of the eyeball of the user of the head-mounted device is imaged at the center of the photosensitive surface 321 of the photosensitive chip 320.

[0051] Optionally, due to Figure 3 The camera module 300 shown in the figure optimizes the structure of the camera module 300 by changing the position between the optical lens 310 and the photosensitive chip 320, thereby optimizing the effect of the image captured by the camera module 300 at a macro distance and at an angle. Figure 3 The camera module 300 shown is relatively large in size and can be applied to head-mounted devices with a large installation space, such as virtual reality helmets. Figure 3 The camera module 300 shown can be installed at the nose pad of the virtual reality helmet. In another optional example, Figure 2 The camera module 300 shown can be installed on the side of the eye of the virtual reality helmet.

[0052] In some other embodiments of the present application, Figure 2 and Figure 3 As shown, in the camera module 300, the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by a second distance d2, a non-zero second angle α2 is provided between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320, a third inclination angle β3 is provided between the lens plane 311 of the optical lens 310 and the focal plane 312, and the photosensitive surface 321, the lens plane 311 and the focal plane 312 intersect at a straight line a. In this embodiment, the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 by a second distance d2, and a non-zero second angle α2 is provided between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320, so as to make the optical center O of the optical lens 310 deviate from the center O' of the photosensitive surface 321 of the photosensitive chip 320. When the camera module 300 is installed on the head-mounted device, the third inclination angle β3 is the inclination angle between the camera module 300 and the eyeball of the user of the head-mounted device, and is also the inclination angle between the lens plane 311 of the optical lens 310 and the eyeball plane of the eyeball of the user of the head-mounted device. At this time, the photosensitive surface 321, the lens plane 311 and the eyeball plane intersect at the straight line a.

[0053] In this embodiment, the optical lens 310 and the photosensitive chip 320 are assembled in such a way that the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 by a second distance d2, and a non-zero second angle α2 is formed between the lens plane 311 and the photosensitive surface 321, thereby obtaining a camera module 300 in which the optical center O of the optical lens 310 deviates from the center O' of the photosensitive surface of the photosensitive chip 320. When the camera module 300 is installed on the head-mounted device at a third inclination angle β3, based on the principle of axis-shift optics, the third inclination angle β3 of the camera module 300 installed on the head-mounted device can be reduced, and the second angle α2 between the lens plane 311 and the photosensitive surface 321 can be reduced while making the focal plane 312 of the optical lens 310 coincide with the eyeball plane of the user of the head-mounted device. This can expand the depth of field of the image taken at a macro and tilted angle by the camera module 300, thereby obtaining an overall clear image including the edge field of view, and at the same time improve the perspective deformation problem of the image taken at an angle by the camera module 300, avoid the deformation effect of the image being larger at the bottom and smaller at the top, and compensate the second angle α2 with the second distance d2, which can reduce the difficulty of designing the optical lens 310.

[0054] Optionally, in the camera module 300, the size of the second distance d2 by which the optical center O of the optical lens 310 is offset from the center O' of the photosensitive surface 321 of the photosensitive chip 320 can be determined according to the size of the third inclination angle β3 of the camera module 300 installed on the head mounted device and the size of the photosensitive surface 321 of the photosensitive chip 320. The size of the second angle α2 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 can be determined according to the size of the third inclination angle β3 of the camera module 300 installed on the head mounted device and the parameters of the optical lens 310.

[0055] Optionally, the third inclination angle β3 of the camera module 300 installed on the head-mounted device can be between 15° and 75°, the second distance d2 of the optical center O of the optical lens 310 offsetting the center O' of the photosensitive surface 321 of the photosensitive chip 320 can be between 50um and 120um, and the second angle α2 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 can be between 1° and 3.5°. In an optional example, the distance between the camera module 300 and the eyeball of the user of the head-mounted device is 13mm, the third inclination angle β3 of the camera module 300 installed on the head-mounted device is 39°, the second distance d2 of the optical center O of the optical lens 310 offsetting the center O' of the photosensitive surface 321 of the photosensitive chip 320 is 100um, and the second angle α2 between the lens plane 311 of the optical lens 310 and the photosensitive surface 321 of the photosensitive chip 320 is 3°.

[0056] Optionally, combined Figure 2 and Figure 3The obtained camera module 300 optimizes the structure of the camera module 300 by simultaneously changing the position and angle between the optical lens 310 and the photosensitive chip 320, thereby optimizing the effect of the image captured by the camera module 300 at a macro distance and at an angle. Figure 2 and Figure 3 The volume of the obtained camera module 300 is still relatively small, and can be applied to head-mounted devices with small installation space, such as augmented reality glasses. In an optional example, Figure 2 The camera module 300 shown can be installed at the nose pad of the augmented reality glasses. In another optional example, Figure 2 The camera module 300 shown can be installed on the side of the eye of the augmented reality glasses.

[0057] The embodiments of the present application also provide a method 1000 for manufacturing a camera module for eye tracking. Figure 4 The flowchart of the manufacturing method 1000 of the camera module for eye tracking according to the embodiment of the present application is shown. The camera module manufactured by the method 1000 of the embodiment of the present application is installed in a head-mounted device, such as an AR and VR head-mounted display device, etc., and the embodiment of the present application is not limited to this. Figure 4 As shown, the manufacturing method 1000 of the camera module applied to eye tracking according to the embodiment of the present application may include the following steps:

[0058] S410, processing an optical lens array having a non-zero preset tilt angle on a glass wafer based on a semiconductor manufacturing process.

[0059] S420, cutting the optical lens array to obtain a single optical lens having a non-zero preset inclination angle.

[0060] S430, for each optical lens with a non-zero preset inclination angle, assemble it with a photosensitive chip based on an active alignment process to obtain a camera module with a non-zero preset inclination angle between the lens plane of the optical lens and the photosensitive surface of the photosensitive chip, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

[0061] The manufacturing method 1000 of the camera module for eye tracking provided in the embodiment of the present application adopts the semiconductor manufacturing process of wafer-level optical elements to directly process an optical lens with a non-zero preset inclination angle on a glass wafer. After the optical lens and the photosensitive chip are assembled based on the active alignment (AA) process, the lens plane of the optical lens in the assembled camera module and the photosensitive surface of the photosensitive chip can have a consistent angle, thereby ensuring the consistency of the direction of the final camera module product and meeting the needs of small-size and rapid mass production of camera modules.

[0062] It should be understood that the steps shown in method 1000 are not exclusive, and other steps may be performed before, after, or between any of the steps shown. In addition, some of the steps shown may be performed simultaneously, or may be performed in different steps. Figure 4 Executed in the order shown.

[0063] In some embodiments of the present application, Figure 5 and Figure 6 As shown, Figure 5 A flow chart of processing an optical lens array on a glass wafer according to an embodiment of the present application is shown. Figure 6 The process flow chart of processing and cutting a glass wafer to obtain a single optical lens according to an embodiment of the present application is shown. Step S410 of this embodiment may include the following steps:

[0064] S510, processing a first optical lens array having a non-zero preset tilt angle on a first glass wafer based on a semiconductor manufacturing process.

[0065] S520, processing a second optical lens array having a non-zero preset tilt angle on a second glass wafer based on a semiconductor manufacturing process.

[0066] S530, based on the alignment of a single first optical lens and a single second optical lens, the first optical lens array and the second optical lens array are spliced ​​to obtain an optical lens array with a non-zero preset inclination angle.

[0067] The optical lens lens of this embodiment is a 2p lens including two lenses, each of which has a non-zero preset tilt angle α. First, a first optical lens array wafer-1 with a tilt angle α is processed on a glass wafer using a semiconductor manufacturing process of wafer-level optical elements. Then, a second optical lens array wafer-2 with a tilt angle α is processed on another glass wafer using a semiconductor manufacturing process of wafer-level optical elements. Since the first optical lens array wafer-1 is parallel to the second optical lens array wafer-2, and the single first optical lens and the single second optical lens in the first optical lens array wafer-1 and the second optical lens array wafer-2 are tilted at a tilt angle α, based on the alignment of the single first optical lens and the single second optical lens, the two optical lens arrays, namely the first optical lens array wafer-1 and the second optical lens array wafer-2, are spliced ​​to obtain a wafer-level optical lens array wafer-3. Finally, the wafer-level optical lens array wafer-3 is cut to obtain a single optical lens lens with a tilt angle α.

[0068] The embodiments of the present application also provide a head-mounted device. The head-mounted device of the embodiments of the present application may include: a device body and a camera module 300 for eye tracking in the above embodiments, and the camera module 300 is installed on the device body. Optionally, the head-mounted device may be an AR and VR head-mounted display device, such as AR glasses, VR helmets, etc., which is not limited in the embodiments of the present application.

[0069] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A camera module for eye tracking, characterized in that: The camera module is installed on the head mounted device, and the camera module includes: an optical lens, facing an eyeball of a user of the head mounted device, and receiving the detection light reflected by the eyeball; and A photosensitive chip, located at the image side of the optical lens, for imaging the detection light projected onto the photosensitive chip through the optical lens; Wherein, the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

2. The camera module according to claim 1, wherein: There is a first inclination angle between the lens plane of the optical lens and the eyeball plane of the eyeball; When the lens plane of the optical lens is parallel to the photosensitive surface, the optical center of the optical lens is offset from the center of the photosensitive surface by a first distance so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

3. The camera module according to claim 2, wherein: The first distance is determined according to the first inclination angle and the size of the photosensitive surface.

4. The camera module according to claim 1, wherein: There is a second inclination angle between the lens plane of the optical lens and the eyeball plane of the eyeball; A non-zero first angle is formed between the lens plane of the optical lens and the photosensitive surface, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip; Wherein, the photosensitive surface, the lens plane and the eyeball plane intersect on a straight line.

5. The camera module according to claim 4, wherein: The first angle is determined according to the second inclination angle and parameters of the optical lens.

6. The camera module according to claim 1, wherein: There is a third inclination angle between the lens plane of the optical lens and the eyeball plane of the eyeball; The optical center of the optical lens is offset from the center of the photosensitive surface by a second distance, and a non-zero second angle is formed between the lens plane of the optical lens and the photosensitive surface, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip; Wherein, the photosensitive surface, the lens plane and the eyeball plane intersect on a straight line.

7. The camera module according to claim 6, wherein: The second distance is determined according to the third inclination angle and the size of the photosensitive surface; The second angle is determined according to the third inclination angle, the second distance and parameters of the optical lens.

8. A method for manufacturing a camera module for eye tracking, characterized in that: The camera module is installed on a head mounted device, and the manufacturing method comprises: An optical lens array having a non-zero preset tilt angle is processed on a glass wafer based on a semiconductor manufacturing process; Cutting the optical lens array to obtain a single optical lens having the preset inclination angle; and For each optical lens with the preset inclination angle, it is assembled with a photosensitive chip based on an active alignment process to obtain a camera module with the preset inclination angle as the included angle between the lens plane of the optical lens and the photosensitive surface of the photosensitive chip, so that the optical center of the optical lens deviates from the center of the photosensitive surface of the photosensitive chip.

9. The manufacturing method according to claim 8, wherein: An optical lens array having a non-zero preset tilt angle is manufactured on a glass wafer based on a semiconductor manufacturing process, including: Processing a first optical lens array having the preset inclination angle on a first glass wafer based on a semiconductor manufacturing process; Processing a second optical lens array having the preset inclination angle on a second glass wafer based on a semiconductor manufacturing process; Based on the alignment of a single first optical lens and a single second optical lens, the first optical lens array and the second optical lens array are spliced ​​to obtain the optical lens array with a preset inclination angle.

10. A head mounted device, characterized in that: include: Equipment body; as well as According to any one of claims 1 to 7, the camera module used for eye tracking is installed on the device body.

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