A method and system for measuring the geometric center alignment of a near-eye display device

Abstract

This invention relates to a method and system for aligning the geometric center of a near-eye display device, comprising the following steps: placing the near-eye display device on a fixture; using a projector to capture images of the near-eye display device and a measuring instrument; and adjusting the position of the near-eye display device based on image analysis results, so that the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements. Since the fixture can fix the near-eye display device, and by capturing the contours of the near-eye display device and the measuring instrument through a projector, their relative positional relationship can be directly measured, guiding the adjustment of the near-eye display device's position so that the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements. This ensures that the measuring instrument is positioned at the spatial location of the near-eye display device's entry point into the eye, thus achieving accurate geometric center alignment between the measuring instrument and the near-eye display device.

Description

Technical Field

[0001] This invention relates to the field of optical measurement technology for near-eye display products, and particularly to a method and system for aligning the geometric center of a near-eye display device. Background Technology

[0002] Currently, NED (Near-eye display), also known as head-mounted display or wearable display, can create virtual images in the field of view of one or both eyes. NED is a technology that uses a display device placed within the non-visual distance of the human eye to render light field information to the eye, thereby reconstructing a virtual scene in front of the eyes. Therefore, AR, VR, MR, and XR products are all collectively referred to as NED at the technical level. Accurately measuring the performance of the reconstructed virtual scene naturally becomes a crucial aspect of NED product manufacturing. NED technology has a relatively complex optical path; while the measurement error is small, the resulting virtual image shows a significant difference. Therefore, it is essential to ensure the accurate geometrical relative position of the measuring instrument and the NED product.

[0003] In related technologies, the current technology of simply fixing NED products with fixtures cannot meet the requirements of measurement position accuracy. Therefore, it is necessary to propose a measurement geometric center alignment method and system for near-eye display devices to perform geometric center alignment before optical measurement of the product, so as to meet the geometric positional relationship between the eyeball and the NED product during actual wear. Summary of the Invention

[0004] This invention provides a method and system for aligning the geometric center of a near-eye display device, to solve the problem that simply fixing the NED product with a fixture in related technologies cannot meet the requirements for measurement position accuracy.

[0005] In a first aspect, a method for aligning the geometric center of a near-eye display device is provided, comprising the following steps: placing the near-eye display device on a fixture; using a projector to capture images of the near-eye display device and the measuring instrument; and adjusting the position of the near-eye display device based on the image analysis results, so that the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements.

[0006] In some embodiments, the step of using a projector to capture images of the near-eye display device and the measuring instrument includes: using two sets of projectors to capture images of the near-eye display device and the measuring instrument respectively, wherein the two sets of projectors are arranged perpendicularly.

[0007] In some embodiments, adjusting the position of the near-eye display device based on image analysis results so that the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements includes: determining whether the positional offset and relative angle between the near-eye display device and the measuring instrument in multiple directions meet threshold requirements based on the image; otherwise, adjusting the position of the near-eye display device so that the positional offset and relative angle between the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements.

[0008] In some embodiments, the step of determining whether the positional offset and relative angle between the near-eye display device and the measuring instrument in multiple directions meets threshold requirements based on the image, and otherwise adjusting the position of the near-eye display device to ensure that the positional offset and relative angle between the near-eye display device and the measuring instrument in multiple spatial directions meets the threshold requirements, includes: calculating the relative angle angle1 and positional offset offset1 between a first line segment and a second line segment based on the image, wherein the first line segment is the line segment formed by the projection of the end face of the measuring instrument in the X-axis direction, and the second line segment is the line segment formed by the projection of the end face of the near-eye display device in the X-axis direction; determining whether the relative angle angle1 meets a first angle threshold and whether the positional offset offset1 meets a first displacement threshold, and otherwise driving the near-eye display device according to the positional offset offset1 and the relative angle angle1. The display device moves along the Y-axis and rotates relative to the Y-axis until the relative angle angle1 meets the first angle threshold and the position offset offset1 meets the first displacement threshold. The relative angle angle2 and position offset offset2 between the third and fourth line segments are calculated based on the image. The third line segment is the line segment formed by the projection of the end face of the measuring instrument onto the Y-axis, and the fourth line segment is the line segment formed by the projection of the end face of the near-eye display device onto the Y-axis. It is determined whether the relative angle angle2 meets the second angle threshold and whether the position offset offset2 meets the second displacement threshold. Otherwise, the near-eye display device is driven to move along the X-axis and rotate relative to the X-axis based on the position offset offset2 and the relative angle angle2 until the relative angle angle2 meets the second angle threshold and the position offset offset2 meets the second displacement threshold.

[0009] In some embodiments, the step of determining whether the positional offset and relative angle between the near-eye display device and the measuring instrument in multiple directions meets the threshold requirements based on the image, and otherwise adjusting the position of the near-eye display device to make the positional offset and relative angle between the near-eye display device and the measuring instrument in multiple spatial directions meet the threshold requirements, further includes: calculating the distance between the third line segment and the fourth line segment, and the length of the fourth line segment; determining whether the difference between the distance and the preset entrance pupil distance meets the distance threshold and whether the length is the shortest, and otherwise driving the near-eye display device to move along the Z-axis and rotate relative to the Z-axis based on the distance and length, until the distance difference meets the distance threshold and the length is the shortest.

[0010] In some embodiments, after determining whether the difference between the distance and the preset entrance pupil distance meets a distance threshold and whether the length is the shortest, and otherwise driving the near-eye display device to move along the Z-axis and rotate relative to the Z-axis based on the distance and length until the distance difference meets the distance threshold and the length is the shortest, the method further includes: determining whether the relative angle 1 meets a first angle threshold and whether the position offset 1 meets a first displacement threshold. If yes, the geometric center alignment ends; otherwise, the position and angle of the near-eye display device along the Y, X, and Z axes are adjusted until the position offsets of the near-eye display device and the measuring instrument along the X, Y, and Z axes all meet the threshold requirements, and the relative angles of the near-eye display device and the measuring instrument along the X, Y, and Z axes all meet the threshold requirements.

[0011] In some embodiments, the near-eye display device is driven to rotate by a preset angle in two opposite directions relative to the Z-axis, and the length of the fourth line segment is calculated in each direction to determine whether the length is the shortest.

[0012] In some embodiments, adjusting the position of the near-eye display device based on image analysis results to make the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements includes: adjusting the position of the near-eye display device based on image analysis results to make the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet a first threshold requirement; and adjusting the position of the near-eye display device based on image analysis results to make the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet a second threshold requirement, wherein the range of the second threshold is smaller than the range of the first threshold.

[0013] Secondly, a measurement geometric center alignment system for a near-eye display device is provided, comprising: an adjustment mechanism with a clamp mounted thereon for placing the near-eye display device; a projector for capturing images of the near-eye display device and a measuring instrument; and a controller connected to the projector and the adjustment mechanism, wherein the controller performs calculations and analyses on the images acquired by the projector and controls the adjustment mechanism to adjust the position of the near-eye display device based on the analysis results, so that the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet threshold requirements.

[0014] In some embodiments, the measurement geometric center alignment system includes two sets of projectors arranged perpendicularly to each other.

[0015] The beneficial effects of the technical solution provided by this invention include:

[0016] This invention provides a method and system for aligning the geometric center of a near-eye display device. Since the fixture can fix the near-eye display device, the contours of the near-eye display device and the measuring instrument can be collected by a projector, and their relative positional relationship can be directly measured. This guides the adjustment of the position of the near-eye display device, so that the relative positions of the near-eye display device and the measuring instrument in multiple spatial directions meet the threshold requirements. This ensures that the measuring instrument is positioned at the spatial location of the near-eye display device's eye-viewing point. Therefore, accurate alignment of the geometric center of the measuring instrument and the near-eye display device can be achieved. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a method for aligning the geometric center of a near-eye display device according to an embodiment of the present invention;

[0019] Figure 2 A flowchart illustrating another method for aligning the geometric center of a near-eye display device according to an embodiment of the present invention;

[0020] Figure 3 A flowchart illustrating another method for aligning the geometric center of a near-eye display device, provided in an embodiment of the present invention;

[0021] Figure 4This is a schematic diagram of the measurement geometric center alignment system for a near-eye display device provided in an embodiment of the present invention.

[0022] In the picture:

[0023] 1. Adjustment mechanism; 2. Fixture; 3. Near-eye display device;

[0024] 4. Projector; 41. Projector A; 42. Projector B; 5. Measuring instrument. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] This invention provides a method and system for aligning the geometric center of a near-eye display device, which solves the problem in related technologies where simply fixing the NED product with a fixture cannot meet the requirements for measurement position accuracy.

[0027] See Figure 1 As shown, an embodiment of the present invention provides a method for aligning the geometric center of a near-eye display device, which may include the following steps:

[0028] S11: The near-eye display device 3 is placed on the clamp 2, and the clamp 2 is used to fix the near-eye display device 3. At the same time, the near-eye display device 3 can be moved to the mechanical positioning position.

[0029] S12: Use projector 4 to take pictures of the near-eye display device 3 and measuring instrument 5. Before step S2, projector 4 can be turned on and used to take pictures of the near-eye display device 3 and measuring instrument 5, ensuring that the near-eye display device 3 and measuring instrument 5 with their close-to-each other end faces are both in the field of view of projector 4.

[0030] S13: Adjust the position of the near-eye display device 3 according to the image analysis results, so that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet the threshold requirements. That is, the relative positional relationship between the near-eye display device 3 and the measuring instrument 5 can be analyzed from the image captured by the projector 4, whether there is any deviation and how much the deviation is, and then the position of the near-eye display device 3 can be adjusted according to the analysis results, so that the near-eye display device 3 and the measuring instrument 5 are aligned in multiple directions.

[0031] In this embodiment, since the clamp 2 can fix the near-eye display device 3, the near-eye display device 3 cannot be moved at will, which is conducive to subsequent precise adjustment. Then, the projector 4 captures the contours of the near-eye display device 3 and the measuring instrument 5 in real time, and can directly measure the relative positional relationship between the near-eye display device 3 and the measuring instrument 5. Based on the measurement and analysis results, the position of the near-eye display device 3 is adjusted so that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet the threshold requirements. Thus, the measuring instrument 5 is placed at the spatial position of the near-eye display device 3's eye-viewing point. Therefore, the geometric center alignment of the measuring instrument 5 and the near-eye display device 3 can be accurately achieved.

[0032] Furthermore, when adjusting the position of the near-eye display device 3, a six-axis robotic arm can be used to adjust the position of the clamp 2, thereby achieving the adjustment of the near-eye display device 3. The six-axis robotic arm can achieve adjustment in six degrees of freedom, namely, movement along the X, Y, and Z axes and rotation angles RX, RY, and RZ (i.e., rotation angles relative to the X, Y, and Z axes). Among them, the Y-axis direction can be vertical, the Z-axis direction can be horizontal and extend along the axis of the near-eye display device 3, and the X-axis direction is also horizontal and perpendicular to the Y and Z axes.

[0033] In some embodiments, see Figure 4 As shown, in step S12, the step of using projectors 4 to capture images of the near-eye display device 3 and the measuring instrument 5 may include: using two sets of projectors 4 to capture images of the near-eye display device 3 and the measuring instrument 5 respectively, wherein the two sets of projectors 4 are arranged perpendicularly. In this embodiment, one set of projectors 4 can be arranged along the X-axis direction, denoted as projector A41, and the other set of projectors 4 can be arranged along the Y-axis direction, with the projection directions of the two sets of projectors 4 perpendicular, denoted as projector B42. Of course, in other embodiments, the Z-axis can also be set as the up-down direction, and the projectors 4 can also be arranged in the Z-axis direction. There is no limitation here, and adjustments can be made according to the actual situation. Using two sets of projectors 4 in two directions to capture images of the near-eye display device 3 allows for the measurement of the position of the near-eye display device 3 from six degrees of freedom in space, controlling the relative positional relationship between the near-eye display device 3 and the measuring instrument 5.

[0034] In some optional embodiments, adjusting the position of the near-eye display device 3 based on image analysis results to ensure that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet threshold requirements may include: determining whether the positional offset and relative angle of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet the threshold requirements based on the image; otherwise, adjusting the position of the near-eye display device 3 to ensure that the positional offset and relative angle of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet the threshold requirements. Here, "multiple directions" includes at least two directions, and the adjustment involves not only determining and adjusting the positional offset in one direction but also determining and adjusting the relative angle between the near-eye display device 3 and the measuring instrument 5. This reduces the angular deviation between the near-eye display device 3 and the measuring instrument 5, effectively minimizing the deviation between their geometric centers.

[0035] Further, see Figure 3 As shown, the step of determining whether the positional offset and relative angle between the near-eye display device 3 and the measuring instrument 5 in multiple directions meet the threshold requirements based on the image, and otherwise adjusting the position of the near-eye display device 3 so that the positional offset and relative angle between the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet the threshold requirements, may include:

[0036] S21: Calculate the relative angle angle1 and position offset1 between the first line segment L1 and the second line segment L2 based on the image. The first line segment L1 is the line segment formed by the projection of the end face of the measuring instrument 5 in the X-axis direction, and the second line segment L2 is the line segment formed by the projection of the end face of the near-eye display device 3 in the X-axis direction. The end face here should be understood as the end faces of the near-eye display device 3 and the measuring instrument 5 that are close to each other. The image used in this step is the image acquired by the projector A41.

[0037] S22: Determine whether the relative angle angle1 satisfies the first angle threshold angle1_limit and whether the position offset offset1 satisfies the first displacement threshold offset1_limit. Otherwise, drive the near-eye display device 3 to move along the Y-axis and rotate relative to the Y-axis according to the position offset offset1 and the relative angle angle1 until the relative angle angle1 satisfies the first angle threshold and the position offset offset1 satisfies the first displacement threshold. If both are satisfied, proceed to step S23.

[0038] S23: Calculate the relative angle angle2 and position offset2 between the third line segment L3 and the fourth line segment L4 based on the image. The third line segment L3 is the line segment formed by the projection of the end face of the measuring instrument 5 in the Y-axis direction, and the fourth line segment L4 is the line segment formed by the projection of the end face of the near-eye display device 3 in the Y-axis direction. The image used in this step is the image acquired by the projector B42.

[0039] S24: Determine whether the relative angle angle2 satisfies the second angle threshold angle2_limit and whether the position offset offset2 satisfies the second displacement threshold offset2_limit. Otherwise, drive the near-eye display device 3 to move along the X-axis and rotate relative to the X-axis according to the position offset offset2 and the relative angle angle2 until the relative angle angle2 satisfies the second angle threshold and the position offset offset2 satisfies the second displacement threshold.

[0040] In step S21, the position offset 1 can be determined by measuring the offset of the midpoints of the first line segment L1 and the second line segment L2 along the Y-axis. Alternatively, other corresponding positions along the Y-axis can be selected, such as the positions of the two endpoints or any position between them. Steps S21 and S22 adjust the near-eye display device 3 so that its position offset along the Y-axis from the measuring instrument 5 is within a first displacement threshold, and the relative angle between the near-eye display device 3 and the measuring instrument 5 along the Y-axis is within a first angle threshold. In step S23, the position offset 1 is determined by... Set2 can measure the offset of the midpoints of the third line segment L3 and the fourth line segment L4 along the X-axis. Alternatively, other corresponding offsets along the X-axis can be selected, such as the positions of the two endpoints or any position between them. Steps S23 and S24 can adjust the near-eye display device 3 so that its positional offset along the X-axis from the measuring instrument 5 is within a second displacement threshold, and the relative angle between the near-eye display device 3 and the measuring instrument 5 along the X-axis is within a second angle threshold, thus ensuring that the geometric center of the near-eye display device 3 is aligned with the geometric center of the measuring instrument 5 as much as possible. Steps S23 and S24 can be interchanged with steps S21 and S22.

[0041] In some embodiments, see Figure 3As shown, the step of determining whether the positional offset and relative angle between the near-eye display device 3 and the measuring instrument 5 in multiple directions meet the threshold requirements based on the image, and adjusting the position of the near-eye display device 3 to make the positional offset and relative angle between the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet the threshold requirements, may further include: calculating the distance between the third line segment L3 and the fourth line segment L4, and the length of the fourth line segment. This step can be performed synchronously with step S23 or after step S23; determining whether the difference between the distance and the preset eye relife meets the distance threshold distance_limit and whether the length is the shortest, and driving the near-eye display device 3 to move along the Z-axis and rotate relative to the Z-axis based on the distance and length until the distance difference meets the distance threshold and the length is the shortest. This step can be performed synchronously with step S24 or after step S24.

[0042] In this embodiment, the distance can be the distance between the centers of the third line segment L3 and the fourth line segment L4. When the difference between the distance and the preset entrance pupil distance meets the distance threshold, it means that the centers of the near eye display device 3 and the measuring instrument 5 are aligned in the Z-axis direction. When the length is the shortest, it means that the end face of the near eye display device 3 is parallel to the end face of the measuring instrument 5. At this time, the relative angle between the near eye display device 3 and the measuring instrument 5 along the Z-axis direction meets the requirements.

[0043] In some optional embodiments, after determining whether the difference between the distance and the preset entrance pupil distance meets a distance threshold and whether the length is the shortest, and otherwise driving the near-eye display device 3 to move along the Z-axis and rotate relative to the Z-axis according to the distance and length until the distance difference meets the distance threshold and the length is the shortest, it may further include: determining whether the relative angle 1 meets a first angle threshold and whether the position offset 1 meets a first displacement threshold. If yes, the geometric center alignment ends; otherwise, the position and angle of the near-eye display device 3 along the Y, X, and Z axes are adjusted until the position offsets of the near-eye display device 3 and the measuring instrument 5 along the X, Y, and Z axes all meet the threshold requirements, and the relative angles of the near-eye display device 3 and the measuring instrument 5 along the X, Y, and Z axes all meet the threshold requirements.

[0044] That is, in this embodiment, after adjusting the X, Y, Z axis positions and RX, RY, RZ rotations of the near-eye display device 3, the relative angle angle1 and position offset1 are judged again to avoid the situation where the previously adjusted Y axis position and angle do not meet the requirements after adjusting the Z axis position and angle, and finally the relative position relationship of the six degrees of freedom is accurate.

[0045] Furthermore, when determining whether the length is the shortest, the near-eye display device 3 can be driven to rotate in two opposite directions relative to the Z-axis by a preset angle (that is, at least twice), and the length of the fourth line segment can be calculated respectively to determine whether the length is the shortest, so as to accurately determine the position of the minimum length.

[0046] In some embodiments, see Figure 2 As shown, adjusting the position of the near-eye display device 3 according to the image analysis results, so that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet threshold requirements, may include: adjusting the position of the near-eye display device 3 according to the image analysis results, so that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet a first threshold requirement; adjusting the position of the near-eye display device 3 according to the image analysis results, so that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet a second threshold requirement, wherein the range of the second threshold is smaller than the range of the first threshold. That is, coarse adjustment of the near-eye display device 3 can be achieved according to the first threshold, and fine adjustment of the near-eye display device 3 can be achieved according to the second threshold, so that the adjustment process can be divided into two parts: large-step coarse adjustment and small-step fine adjustment, gradually adjusting the center of the near-eye display device 3 and the center of the measuring instrument 5 to an aligned state. The first threshold for angles (RX, RY, RZ) can be denoted as the error threshold angle_pre, and the first threshold for displacements (X, Y, Z) can be denoted as the error threshold offset_pre; the second threshold for angles (RX, RY, RZ) can be denoted as the error threshold angle_end, and the second threshold for displacements (X, Y, Z) can be denoted as the error threshold offset_end.

[0047] The measurement geometric center alignment method for near-eye display devices provided by this invention uses a projector 4 to acquire the contours of the near-eye display device 3 and the measuring instrument 5, allowing direct measurement of their relative positional relationship. Furthermore, it analyzes the positional characteristics between the near-eye display device 3 and the measuring instrument 5 from a six-degree-of-freedom spatial perspective. The cross-shaped placement of the projector 4 not only obtains the relative positional relationship between the near-eye display device 3 and the measuring instrument 5 across the six degrees of freedom but also avoids interfering with the final measurement of the optical performance of the near-eye display device 3. This method can simulate the installation position of the NED module on the final product before assembly, thus accurately reflecting the true optical performance of the final assembled product. If simulated assembly and testing of the NED module before shipment can identify defective products, saving on round-trip transportation costs, and simulating performance testing before assembly can eliminate defective products, preventing the complex work of disassembly after assembly.

[0048] See Figure 4 As shown in the figure, a measurement geometric center alignment system for a near-eye display device provided in an embodiment of the present invention may include: an adjustment mechanism 1, on which a clamp 2 is mounted for placing the near-eye display device 3; wherein the adjustment mechanism 1 may be a six-axis manipulator capable of moving in six degrees of freedom; a projector 4 for capturing images of the near-eye display device 3 and the measuring instrument 5; and a controller connected to the projector 4 and the adjustment mechanism 1, wherein the controller performs calculation and analysis on the images acquired by the projector 4 and controls the adjustment mechanism 1 to adjust the position of the near-eye display device 3 according to the analysis results, so that the relative positions of the near-eye display device 3 and the measuring instrument 5 in multiple spatial directions meet threshold requirements.

[0049] In this embodiment, a high-precision projector 4 is used to capture images in real time. The algorithm built into the controller can analyze the geometric relative position relationship between the near-eye display device 3 and the measuring instrument 5 in real time. Furthermore, the six-axis control system of the adjustment mechanism 1 is used to guide the six-axis adjustment mechanism 1 to make adjustments in real time based on the results of the algorithm feedback, thereby controlling the geometric relative position relationship between the near-eye display device 3 and the measuring instrument 5 from six degrees of freedom in space.

[0050] In some embodiments, the measurement geometric center alignment system may include two sets of projectors 4, which are arranged perpendicularly. The two sets of projectors 4 are projector A41 and projector B42, with projector A41 arranged along the X-axis and projector B42 arranged along the Y-axis.

[0051] The measurement geometric center alignment system for near-eye display devices provided in this embodiment of the invention can use a projector 4 to capture the geometric positional relationship between the near-eye display device 3 and the measuring instrument 5 in real time, and guide the six-axis adjustment mechanism 1 to adjust the relative position between the near-eye display device 3 and the measuring instrument 5, so that the measuring instrument 5 is positioned at the spatial position of the near-eye display device 3 at the eye entrance point, and ultimately satisfy the geometric positional relationship between the eyeball and the near-eye display device 3 during actual wear.

[0052] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0053] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0054] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for aligning the geometric center of a near-eye display device, characterized in that, It includes the following steps: Place the near-eye display device (3) on the fixture (2); The near-eye display device (3) and the measuring instrument (5) are captured using a projector (4); Adjusting the position of the near-eye display device (3) based on the image analysis results, so that the relative positions of the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet threshold requirements, including: Based on the image, determine whether the positional offset and relative angle between the near-eye display device (3) and the measuring instrument (5) in multiple directions meet the threshold requirements; otherwise, adjust the position of the near-eye display device (3) so that the positional offset and relative angle between the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet the threshold requirements.

2. The measurement geometric center alignment method for a near-eye display device as described in claim 1, characterized in that, The process of using a projector (4) to capture images of the near-eye display device (3) and the measuring instrument (5) includes: Two sets of projectors (4) are used to take pictures of the near-eye display device (3) and the measuring instrument (5) respectively, wherein the two sets of projectors (4) are arranged vertically.

3. The measurement geometric center alignment method for a near-eye display device as described in claim 1, characterized in that, The step of determining whether the positional offset and relative angle between the near-eye display device (3) and the measuring instrument (5) in multiple directions meet the threshold requirements based on the image, and otherwise adjusting the position of the near-eye display device (3) so that the positional offset and relative angle between the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet the threshold requirements, includes: The relative angle angle1 and position offset offset1 between the first line segment and the second line segment are calculated based on the image. The first line segment is the line segment formed by the projection of the end face of the measuring instrument (5) in the X-axis direction, and the second line segment is the line segment formed by the projection of the end face of the near-eye display device (3) in the X-axis direction. Determine whether the relative angle angle1 meets the first angle threshold and whether the position offset offset1 meets the first displacement threshold. Otherwise, drive the near-eye display device (3) to move along the Y-axis and rotate relative to the Y-axis according to the position offset offset1 and the relative angle angle1 until the relative angle angle1 meets the first angle threshold and the position offset offset1 meets the first displacement threshold. The relative angle angle2 and position offset offset2 between the third line segment and the fourth line segment are calculated based on the image. The third line segment is the line segment formed by the projection of the end face of the measuring instrument (5) in the Y-axis direction, and the fourth line segment is the line segment formed by the projection of the end face of the near-eye display device (3) in the Y-axis direction. Determine whether the relative angle angle2 meets the second angle threshold and whether the position offset offset2 meets the second displacement threshold. Otherwise, drive the near-eye display device (3) to move along the X-axis and rotate relative to the X-axis according to the position offset offset2 and the relative angle angle2 until the relative angle angle2 meets the second angle threshold and the position offset offset2 meets the second displacement threshold.

4. The measurement geometric center alignment method for a near-eye display device as described in claim 3, characterized in that, The step of determining whether the positional offset and relative angle between the near-eye display device (3) and the measuring instrument (5) in multiple directions meet the threshold requirements based on the image, and otherwise adjusting the position of the near-eye display device (3) so that the positional offset and relative angle between the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet the threshold requirements, further includes: Calculate the distance between the third line segment and the fourth line segment, and the length of the fourth line segment; Determine whether the difference between the distance and the preset entrance pupil distance meets the distance threshold and whether the length is the shortest. Otherwise, drive the near-eye display device (3) to move along the Z-axis and rotate relative to the Z-axis according to the distance and length until the distance difference meets the distance threshold and the length is the shortest.

5. The measurement geometric center alignment method for a near-eye display device as described in claim 4, characterized in that, After determining whether the difference between the distance and the preset entrance pupil distance meets the distance threshold and whether the length is the shortest, and otherwise driving the near-eye display device (3) to move along the Z-axis and rotate relative to the Z-axis according to the distance and length until the distance difference meets the distance threshold and the length is the shortest, the method further includes: Determine whether the relative angle angle1 meets the first angle threshold and whether the position offset offset1 meets the first displacement threshold. If so, the geometric center alignment ends; otherwise, continue to adjust the position and angle of the near-eye display device (3) along the Y, X, and Z axes until the positional offset of the near-eye display device (3) and the measuring instrument (5) along the X, Y, and Z axes meets the threshold requirements, and the relative angle of the near-eye display device (3) and the measuring instrument (5) along the X, Y, and Z axes meets the threshold requirements.

6. The measurement geometric center alignment method for a near-eye display device as described in claim 4, characterized in that: Drive the near-eye display device (3) to rotate by a preset angle in two opposite directions relative to the Z-axis, and calculate the length of the fourth line segment respectively, and determine whether the length is the shortest.

7. The measurement geometric center alignment method for a near-eye display device as described in claim 1, characterized in that, The step of adjusting the position of the near-eye display device (3) based on the image analysis results, so that the relative positions of the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet the threshold requirements, includes: The position of the near-eye display device (3) is adjusted according to the image analysis results so that the relative positions of the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet the first threshold requirement; The position of the near-eye display device (3) is adjusted according to the image analysis results so that the relative positions of the near-eye display device (3) and the measuring instrument (5) in multiple spatial directions meet the second threshold requirements, wherein the range of the second threshold is smaller than the range of the first threshold.

8. A measurement geometric center alignment system for a near-eye display device, characterized in that, It includes: An adjustment mechanism (1) is provided, on which a clamp (2) is mounted, the clamp (2) being used to place a near-eye display device (3); Projector (4), the projector (4) is used to take pictures of the near-eye display device (3) and the measuring instrument (5); The controller is connected to the projector (4) and the adjustment mechanism (1). The controller is used to calculate and analyze the image acquired by the projector (4) and control the adjustment mechanism (1) to adjust the position of the near-eye display device (3) according to the analysis result, so that the relative position of the near-eye display device (3) and the measuring instrument (5) in multiple directions in space meets the threshold requirements.

9. The measurement geometric center alignment system for a near-eye display device as described in claim 8, characterized in that: The measurement geometric center alignment system includes two sets of projectors (4), and the two sets of projectors (4) are arranged perpendicularly.

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