Detection module and near-to-eye display module

Abstract

The embodiment of the invention discloses a detection module and a near-to-eye display module. The detection module comprises an optical waveguide and a detection unit, wherein the optical waveguide at least comprises a coupling-in region and a coupling-out region; the coupling-in area enables image light to be coupled into the optical waveguide and enables a part of the image light to be transmitted to the coupling-out area; the coupling-out area is used for expanding and propagating the image light and coupling out a part of the expanded image light; the detection unit performs detection based on the image light propagating within the optical waveguide.

Description

Technical Field

[0001] The present application relates to the field of scanning display technology, and specifically to a detection module and a near-eye display module. Background Art

[0002] Augmented reality (AR) devices, such as AR glasses, have become a research hotspot in the display industry. Light engines combined with optical waveguides have become a mainstream optical solution for AR glasses.

[0003] Some existing solutions add corresponding detection devices to AR glasses to detect whether the image output by the light engine is abnormal. For example, the detection device is placed opposite the light engine's light output position (located outside the waveguide lens), so that some light is transmitted through the waveguide and received by the detection device, or a corresponding spectroscopic structure is set to deflect part of the light output from the light engine to the detection device's target surface. However, these methods will increase the local size of the AR glasses (such as the thickness of the frame and the diameter of the temples). Moreover, to ensure the accuracy of the detection results, especially for scanning light engines, the detection device usually amplifies the differences in motion amplitude and phase as much as possible. Amplifying the differences often requires a larger detection device, which is also not conducive to the local miniaturization of AR glasses. Summary of the Invention

[0004] Based on the above content, the present application provides a detection module and a near-eye display module to facilitate the miniaturization of the local volume of AR glasses while providing detection functions.

[0005] Based on one aspect of the present application, an embodiment of the present application provides a detection module, which includes an optical waveguide and a detection unit; wherein,

[0006] The optical waveguide at least comprises an incoupling region and an outcoupling region;

[0007] The coupling-in region couples the image light into the optical waveguide and propagates a portion of the image light toward the coupling-out region;

[0008] The outcoupling region is used to expand and propagate the image light and couple out a portion of the expanded image light;

[0009] The detection unit performs detection based on the image light propagating in the optical waveguide.

[0010] Optionally, the optical waveguide further includes a detection outcoupling region, and the detection unit is arranged in conjunction with the detection outcoupling region.

[0011] Optionally, the detection outcoupling region is arranged on the optical path of the image light that continues to propagate in the waveguide matrix after passing through the outcoupling region, and the detection target surface of the detection unit is arranged toward the detection outcoupling region.

[0012] Optionally, the detection outcoupling area is symmetrically arranged based on the optical path of the image light corresponding to the central field of view of the image.

[0013] Optionally, the detection outcoupling area includes at least two independent sub-areas, and the sub-areas are based on the optical path distribution of the image light corresponding to the central field of view of the image;

[0014] The detection unit includes a detection subunit corresponding to the sub-area, and a detection target surface of the detection subunit is arranged toward the sub-area.

[0015] Optionally, the detection outcoupling area includes a first detection outcoupling area and a second detection outcoupling area, wherein:

[0016] The first detection outcoupling region is arranged on an optical path of the image light that continues to propagate in the waveguide matrix after passing through the outcoupling region, and the first detection outcoupling region deflects a portion of the image light to the second detection outcoupling region;

[0017] The second detection outcoupling region is arranged on the optical path of the image light deflected by the first detection outcoupling region;

[0018] The detection unit includes a first detection unit and a second detection unit;

[0019] The first detection unit is matched with the first detection outcoupling area, and the second detection unit is matched with the second detection outcoupling area.

[0020] Optionally, the first detection unit is arranged at a position such that a detection target surface in the first detection unit receives image light coupled out by the first detection outcoupling area and corresponding to the upper and lower parts of the image field of view;

[0021] The second detection unit is arranged at a position such that the detection target surface in the second detection unit receives the image light coupled out by the second detection outcoupling area and corresponding to the left and right parts of the image field.

[0022] Optionally, the optical waveguide comprises at least two stacked optical waveguide sheets, each of which is provided with at least one detection outcoupling region;

[0023] The number of the detection units corresponds to the detection outcoupling region, and the detection units are located outside the optical waveguide and match the positions of the detection outcoupling region.

[0024] Optionally, the detection unit is arranged at an edge of the optical waveguide and is located on the optical path of the image light that passes through the outcoupling region and continues to propagate in the optical waveguide.

[0025] Optionally, the detection unit is attached to the optical waveguide.

[0026] Based on one aspect of the present application, an embodiment of the present application provides a near-eye display module, which includes a light engine and a detection module described in any one of claims 1 to 9, wherein the light engine is used to generate image light, and the detection module performs display and detection based on the image light.

[0027] Other features and advantages of the present application will be described in the following description and, in part, will become apparent from the description or be understood through implementation of the technical solutions of the present application. The objectives and other advantages of the present application can be achieved and obtained through the structures and / or processes specifically pointed out in the description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0029] Figure 1 This is a schematic structural diagram of the first detection module provided in an embodiment of the present application;

[0030] Figure 2a Schematic diagram of the propagation of light entering the optical waveguide provided by an embodiment of the present application;

[0031] Figure 2b is a schematic diagram of a test image 20 provided in an embodiment of the present application;

[0032] Figure 3a This is a schematic diagram of detecting a normal state of an image provided by an embodiment of the present application;

[0033] Figure 3b This is a schematic diagram of detecting an abnormal state of an image provided by an embodiment of the present application;

[0034] Figure 4 Schematic diagram of the structure of the second detection module provided in the embodiment of the present application;

[0035] Figure 5 Schematic diagram of the structure of the third detection module provided in the embodiment of the present application;

[0036] Figure 6 It is a structural diagram of the fourth detection module provided in an embodiment of the present application. DETAILED DESCRIPTION

[0037] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the relevant invention are shown in the accompanying drawings.

[0038] In the embodiment of the present application, the light engine can be based on at least one display technology or device suitable for the field of AR glasses, such as LCOS, MicroLED, MicroOLED, Micro-Electro-Mechanical Systems (MEMS) scanning mirror, and fiber scanner.

[0039] In actual applications, AR glasses face the risk of bending temples when users put them on and take them off, as well as vibration and rotation during use, which can cause abnormal images output by the light engine. In particular, scanning light engines (such as those composed of scanning devices such as MEMS scanning mirrors and fiber scanners) typically use two-dimensional scanning for scanning and display. That is, the scanning trajectory is formed by coupling motion in the longitudinal and lateral directions. However, during the actual scanning process, due to factors such as manufacturing / installation deviations and vibration nonlinearity, the amplitude and phase of the scanning device's motion in the two directions may not match, causing the scanning trajectory to deviate from the ideal trajectory and resulting in display anomalies.

[0040] It should be noted that the image anomalies / differences described in the embodiments of this application can be considered to be abnormalities in the image displayed / output by the corresponding light engine. For example, in a scanning light engine, raster scanning may cause unexpected image anomalies. Detecting these image anomalies / differences is crucial for subsequent image correction.

[0041] In the embodiment of the present application, a detection module 10 is provided, referring to Figure 1 The detection module 10 includes: an optical waveguide 100 and a detection unit 200 configured in conjunction with the optical waveguide 100 .

[0042] refer to Figure 1 , an optical waveguide 100 provided in an embodiment of the present application, comprising: a waveguide substrate 101, an incoupling region 102, an outcoupling region 103, and a detection outcoupling region 104. The incoupling region 102, the outcoupling region 103, and the detection outcoupling region 104 are all arranged on the waveguide substrate 101. A grating structure is arranged in the incoupling region 102, the outcoupling region 103, and the detection outcoupling region 104. The grating structure can be realized by processes such as imprinting, coating, and etching, which are not limited here. In addition, Figure 1The outline, size, and relative position of the coupling-in region 102, the coupling-out region 103, and the detection coupling-out region 104 shown in FIG are exemplary and are not limited to Figure 1 shown.

[0043] Figure 1 The xy coordinate system is shown in FIG: The direction parallel to the y-axis may also be referred to as the first direction, vertical direction, or longitudinal direction in this application; the direction parallel to the x-axis may also be referred to as the second direction, horizontal direction, or transverse direction in this application. In the embodiment of the present application, the direction perpendicular to the xy plane may be considered as the z-axis direction (in Figure 1 (Not shown in the figure, the direction parallel to the z-axis may also be referred to as the third direction in this application). In the subsequent embodiments, some views will adopt different perspectives, but unless otherwise specified, the same perspectives will be used. Figure 1 The coordinate system in the text and the corresponding direction names are also applicable throughout the text, even if the image viewing angle is different from Figure 1 Although there are some differences, the coordinate system remains the same and will not be explained separately in the subsequent description.

[0044] In the embodiment of the present application, the grating structure provided in the coupling-in region 102 may be referred to as: coupling-in grating, and the specific grating type may be a one-dimensional grating or a two-dimensional diffraction grating; the grating structure provided in the coupling-out region 103 may be referred to as: coupling-out grating, and the specific grating type may be a two-dimensional diffraction grating. In the subsequent description, the two-dimensional diffraction grating may be referred to as a two-dimensional grating. The grating type in the detection coupling-out region 104 may be a one-dimensional grating or a two-dimensional grating, which will be determined according to actual needs. In some embodiments, the grating structure in the detection coupling-out region 104 may be different from the grating structures in the coupling-in region 102 and the coupling-out region 103; and in some embodiments, the same grating structure may be used. In Figure 1 In the example shown, the grating structures provided in the coupling-in region 102 and the coupling-out region 103 are both two-dimensional gratings, and the grating structure provided in the detection coupling-out region 104 is a one-dimensional grating.

[0045] refer to Figure 2a , which shows the propagation of the image light 14 entering the optical waveguide 100. Specifically, the image light 14 is coupled into the coupling region 102 at a set propagation angle and azimuth angle (in this embodiment, the propagation angle is denoted as θ and the azimuth angle is denoted as ψ). In this example, the coupling grating in the coupling region 102 is a two-dimensional diffraction grating. Under the action of the two-dimensional diffraction grating, the image light 14 will form an expanded image light. The corresponding optical path is shown as follows: Figure 2a 140, 141 and 142 shown in FIG. Of course, after the coupling region ( Figure 2a After that, part of the image light will be coupled out from the optical waveguide 100 through the outcoupling region, and part of the image light will continue to be transmitted in the optical waveguide 100 while maintaining the propagation angle θ and the azimuth angle ψ.

[0046] Further references Figure 2b ,exist Figure 2a Based on the example of the propagation of the image light 14 shown, for the test image 20, several measuring points D are set therein. ij (Specifically, a 5*5 dot matrix, i.e., i, j = 1 to 5). The test pattern 20 can be output by the corresponding light engine to the optical waveguide 100, and the propagation angle and azimuth angle of the image light coupled into the optical waveguide 100 at the corresponding measurement points are measured. The propagation angle θ and azimuth angle ψ corresponding to the image light at each measurement point can be referred to in Tables 1 and 2, respectively.

[0047] θ 1 2 3 4 5 1 44.85 41.30 37.86 34.56 31.47 2 44.77 41.20 37.74 34.43 31.32 3 44.74 41.16 37.69 34.38 31.27 4 44.77 41.20 37.74 34.43 31.32 5 44.85 41.30 37.86 34.56 31.47

[0048] Table 1

[0049]

[0050] Table 2

[0051] As shown in Table 2 above, the azimuth angle ψ of the image light emitted from each measurement point in the upper and lower fields of view of test image 20 is not zero. As the lateral propagation distance increases, the degree of separation of the image light in the upper and lower fields of view gradually increases. However, the azimuth angle ψ of the image light emitted from the measurement point in the central field of view of test image 20 is zero. As the lateral propagation distance increases, the image light in this central field of view maintains its azimuth angle ψ at zero and continues to propagate.

[0052] Based on this, continue to refer to Figure 1 In this embodiment, the detection coupling-out region 104 is located on one side of the coupling-out region 103 (at Figure 1 , located to the right of the outcoupling region 103 (this side is opposite to the incoupling region 102 and is located on the optical path of the image light that continues to propagate within the waveguide 100). Furthermore, the image light corresponding to the central field of view of the image that continues to propagate within the optical waveguide 100 passes through the detection outcoupling region 104. This arrangement allows image light corresponding to the upper and lower fields of view of the image with a sufficient degree of separation to pass through the detection outcoupling region 104. In conjunction with the detection unit 200, anomalies in the upper and lower fields of view of the image can be more effectively detected.

[0053] In a preferred embodiment, the detection outcoupling regions 104 are arranged axially symmetrically with respect to the optical path of light corresponding to the image's central field of view (hereinafter referred to as the image central field of view light, and its corresponding optical path as the image central field of view optical path). Image light corresponding to the upper and lower image fields of view pass through the detection outcoupling regions 104 and are coupled out. The symmetrical arrangement of the detection outcoupling regions 104 allows for more distinct detection of differences between the upper and lower image fields of view.

[0054] Continue to refer Figure 1 The optical waveguide 100 is fabricated into a lens morphology (in this example, the lens corresponds to the user's left eye). The detection unit 200, configured in conjunction with the detection outcoupling region 104, includes two detection regions 200a and 200b. The detection unit 200 is arranged such that the detection regions are distributed along a first direction. Specifically, one detection region 200a of the detection unit 200 primarily receives image light from the upper half of the field of view, while the other detection region 200b primarily receives image light from the lower half of the field of view. This allows the detection unit 200 to detect image anomalies (e.g., scanning trajectory anomalies) based on the difference in image light corresponding to the two fields of view.

[0055] In the embodiment of the present application, the detection unit 200 can be a photodetector, such as a multi-quadrant detector, or other detection device with the function of collecting light differences. In this embodiment, the detection unit 200 is a dual-quadrant detector. Of course, in different embodiments, the detection unit 200 can take different forms. For example, in some embodiments, the detection unit 200 can include two single-target detectors; in other embodiments, the detection unit 200 can include more than two detection areas or detection target surfaces. Usually, when setting up, multiple detection areas or detection target surfaces can be distributed on both sides of the transverse symmetry axis of the detection coupling-out region 104 to fully receive the image light corresponding to the upper and lower fields of view in the image. The specific form will depend on the actual application needs.

[0056] In order to illustrate the relative position relationship between the detection unit 200 and the detection outcoupling region 104 and the light propagation between the two, Figure 1 There is a certain distance between the detection unit 200 and the optical waveguide 100, and Figure 1 The black arrows in the figure represent the image light coupled out from the detection outcoupling region 104. In fact, as a preferred embodiment, the detection unit 200 can be fixed to the position of the detection outcoupling region 104 by means of attachment, and the detection unit 200 is attached and arranged symmetrically with the image center field optical path as the axis.

[0057] Of course, the detection unit 200 can be disposed on the surface of the optical waveguide 100 on the side where the incoupling region 102 and the outcoupling region 103 are located (the side facing the human eye when used as AR glasses), or on the opposite side of the optical waveguide 100 (the side facing away from the human eye when used as AR glasses). Accordingly, the grating structure in the outcoupling detection region 104 will be designed accordingly to allow the image light to be coupled out in the corresponding direction.

[0058] In some embodiments, the detection unit 200 can also be respectively arranged on the two side surfaces of the optical waveguide 100, and is used to respectively receive image light corresponding to the upper and lower parts of the image field of view. Correspondingly, the detection coupling area 104 will couple the corresponding image light toward the two sides of the optical waveguide 100.

[0059] After the image light entering the optical waveguide 100 propagates a certain distance, the image light corresponding to the upper and lower parts of the image field of view will gradually separate. By setting a detection outcoupling area at a specific position on the optical waveguide 100 and coordinating the corresponding detection unit, this method allows the detection process to occur entirely on the optical waveguide 100. When applied to AR glasses, it can further avoid designing additional detection optical paths in other locations of the AR glasses, and also avoid the detection unit occupying other locations of the AR glasses, thereby facilitating the local miniaturization design of the AR glasses.

[0060] Based on the aforementioned detection module 10, the difference between the upper and lower parts of the image field can be detected. Figure 3a and 3b , showing the normal state and abnormal state of tilt of image 21, as well as the detection status of detection unit 200 in these states. Specifically, test pattern area 210 in image 21 displays a solid red pattern. The color and / or brightness displayed in this area are significantly different from the rest of the image 21, allowing detection unit 200 to more effectively capture the light difference.

[0061] It should be understood that in the embodiment of the present application, the content displayed in the test pattern area is not limited to a red image, and may also include test patterns of other colors and filling content (such as grid lines); and the scope of the test pattern area is not limited to Figure 3a and Figure 3b As shown in , a larger range can be used, or even the entire image can be used as the test pattern area.

[0062] The dotted line in the figure represents the dividing line between the upper and lower fields of view of the image 21 when it is in a normal state. The dotted line also corresponds to the light with an azimuth angle ψ of 0 in the central field of view of the image 21. The detection unit 200 is symmetrically arranged in the Y-axis direction based on the dotted line, so that the two detection areas 200a and 200b will respectively receive the light corresponding to the upper and lower fields of view of the image 21.

[0063] Figure 3a , which is the normal state of the image 21 , at which time the light of the test pattern collected by the detection unit 200 is evenly distributed on the two detection target surfaces 200 a and 200 b of the detection unit 200 .

[0064] Figure 3b , an abnormal state of image 21 tilted is shown, i.e., image 21 tilts along the X-axis, with the left side higher and the right side lower. In this case, the distribution of the test pattern light collected by the detection unit 200 on the two detection target surfaces 200a and 200b is uneven. Specifically, detection target surface 200a receives more red light, while detection target surface 200b receives less red light.

[0065] Obviously, the detection unit 200 is symmetrically arranged so that the image light of the upper and lower fields of view of the image 21 can be received by the detection areas 200a and 200b respectively. Therefore, when the image 21 is abnormally tilted, the abnormal tilt state can be detected more accurately through the specific light received and accumulated by the two detection areas 200a and 200b.

[0066] In some implementations, the image may also produce an abnormal bending state in the Y-axis direction. Alternatively, in some embodiments, for a scanning light engine, the image output by the scan may also have a longitudinal delay difference. The difference is manifested as the content that should have been displayed at the predetermined position is actually displayed at another position below the predetermined position due to the longitudinal delay.

[0067] Judging from the imaging results, the above-mentioned image differences / abnormalities are all reflected in the vertical direction of the image. In other words, there are differences / abnormalities in the content displayed in the upper and lower parts of the image field of view. The detection module in this solution can effectively collect the above-mentioned image differences and thus realize detection.

[0068] In addition to the above-mentioned image differences / abnormalities in the longitudinal direction (one-dimensional direction) of the image, image differences / abnormalities in the two-dimensional direction may also occur, that is, image differences / abnormalities are reflected between the upper and lower fields of view and between the left and right fields of view.

[0069] In this regard, in an embodiment of the present application, a detection module 30 is provided, referring to Figure 4 The detection module 30 includes: an optical waveguide 300 and detection units 400 and 500.

[0070] exist Figure 4In the figure, the optical waveguide 300 includes a waveguide substrate 301, an incoupling region 302, an outcoupling region 303, a first detection outcoupling region 304, and a second detection outcoupling region 305. The incoupling region 302, the outcoupling region 303, the first detection outcoupling region 304, and the second detection outcoupling region 305 are all disposed on the waveguide substrate 301 and each has a grating structure disposed therein.

[0071] The grating type provided in the first detection outcoupling region 304 may be a two-dimensional grating, and the grating type provided in the second detection outcoupling region 305 may be a one-dimensional grating or a two-dimensional grating.

[0072] The grating types in each region may be the same or different. When the same grating type is used, the specific grating structures may be different. In some embodiments, the same grating structure may also be used. The specific decision will be based on actual needs.

[0073] exist Figure 4 In the example shown, the grating types set in the coupling-in region 302 , the coupling-out region 303 and the first detection region 304 are all two-dimensional gratings, and the grating type set in the second detection region 305 is a one-dimensional grating.

[0074] Continue to refer Figure 4 The positions of the first detection outcoupling region 304 and the second detection outcoupling region 305 are associated with the image light corresponding to the central field of view of the image. Specifically, after being coupled into the optical waveguide 300 via the coupling region 302, a certain image light expands and propagates within the optical waveguide 300. The expanded image light forms corresponding optical paths 34 and 35. After passing through the outcoupling region 303, optical paths 34 and 35 further pass through the first detection outcoupling region 304. Taking optical path 34 as an example, when passing through the first detection outcoupling region 304, a portion of the image light propagating along optical path 34 is deflected by the grating in the first detection outcoupling region 304. The deflected image light forms optical paths 340 and 341. Optical paths 340 and 341 pass through the second detection outcoupling region 305.

[0075] Of course, when the image light passes through the outcoupling region 303, the first detection outcoupling region 304 and the second detection outcoupling region 305, a portion of the image light is outcoupled under the action of the grating structure therein ( Figure 4 The outcoupling efficiency depends on the grating structure and is not specifically limited in this application. It should be noted that when the image light passes through the first detection outcoupling region 304, a portion of the image light continues to propagate within the waveguide matrix 301 at its original propagation angle and azimuth. When the deflected image light passes through the second detection outcoupling region 305, a portion of the image light also continues to propagate within the waveguide matrix 301 at its deflected propagation angle and azimuth.

[0076] The detection unit 400 is arranged in a manner that the detection areas are distributed in the first direction, that is, a detection area 400a of the detection unit 400 is mainly used to receive image light of the upper half of the field of view in the image (eg, Figure 4 The other detection area 400b is mainly used to receive the image light of the lower half of the field of view in the image (eg, Figure 4 The image light corresponding to the middle optical path 35 is thus enabled to detect image anomalies (eg, scanning track anomalies) based on the difference in image light corresponding to the upper and lower fields of view.

[0077] The detection unit 500 provided in conjunction with the second detection outcoupling region 305 includes two detection regions 500a and 500b. The detection unit 500 is provided in such a manner that the detection regions are distributed in the second direction, that is, one detection region 500a of the detection unit 500 is mainly used to receive image light of the left half of the field of view in the image (e.g., Figure 4 The other detection area 500b is mainly used to receive the image light of the right half of the field of view in the image (eg, Figure 4 The image light corresponding to the middle optical path 341 is thus enabled to detect image anomalies (eg, scanning track anomalies) based on the difference in image light corresponding to the left and right fields of view.

[0078] In some embodiments, the detection unit 400 and the detection unit 500 can fully receive the image light coupled out by the first detection coupling area 304 and the second detection coupling area 305, but it should be understood that in some embodiments, affected by factors such as the installation position of the detection unit and the size of the target surface, it is also feasible for the detection unit to receive a portion of the image light, and the amount of image light received can be sufficient to detect image abnormalities.

[0079] The aforementioned arrangement allows image light rays corresponding to the upper and lower fields of view, with sufficient separation, to pass through first detection outcoupling region 304 (a portion of the image light rays are coupled outward). Furthermore, image light rays corresponding to the left and right fields of view, with sufficient separation, are deflected by first detection outcoupling region 304 and pass through second detection outcoupling region 305 (a portion of the image light rays are coupled outward). Based on the image light rays coupled outward from these two detection regions and in conjunction with the corresponding detection units, both horizontal and vertical differences in the image can be detected.

[0080] In a preferred embodiment, the first detection outcoupling regions 304 are arranged axially symmetrically with respect to the optical path of the light corresponding to the horizontal image center field of view (hereinafter referred to as the "horizontal image center field of view light" and its corresponding optical path as the "horizontal image center field of view optical path"). Image light corresponding to the upper and lower image fields of view pass through the first detection outcoupling regions 304 and are coupled out. The symmetrical arrangement of the first detection outcoupling regions 304 allows for more distinct detection of differences between the upper and lower image fields of view.

[0081] Accordingly, second detection outcoupling region 305 is arranged axially symmetrically about the optical path of the light corresponding to the longitudinal image center field of view deflected by first detection outcoupling region 304 (in the subsequent description, this light may be referred to as the longitudinal image center field of view light; its corresponding optical path may be referred to as the longitudinal image center field of view light path). Image light corresponding to the left and right image fields of view will pass through second detection outcoupling region 305 and be coupled out. Because second detection outcoupling region 305 is arranged in a symmetrical distribution, the difference between the left and right image fields of view can be more clearly detected.

[0082] It should be noted that, in a feasible embodiment, not all image light in the upper and lower fields of view of the image passes through the first detection outcoupling area 304. Accordingly, the image light deflected by the first detection outcoupling area 304 is not all image light passing through the first detection outcoupling area 304. It can be understood that in the solution of the present application, the number of image light passing through the first detection outcoupling area 304 and the second detection outcoupling area 305 is sufficient for detection.

[0083] Similarly, the detection units 400 and 500 can also be photoelectric detectors, such as multi-quadrant detectors, or other detection devices with the function of collecting light differences. In this embodiment, the detection units 400 and 500 are dual-quadrant detectors. Of course, in different embodiments, the detection units 400 and / or 500 can adopt different forms. For details, please refer to the description of the detection unit 200, which will not be repeated here. Moreover, in order to illustrate the relative position relationship between the detection units 400, 500 and the detection coupling units 304, 305 of the waveguide 300 and the light propagation between the two, therefore, Figure 4 There is a certain distance between the detection units 400, 500 and the optical waveguide 300, and Figure 4 The black arrows in FIG. 3 represent the image light coupled out from the detection outcoupling units 304 and 305. In fact, as a preferred embodiment, the detection units 400 and 500 can be fixed to the first detection outcoupling area 304 and the second detection outcoupling area 305 respectively by attachment.

[0084] Of course, the aforementioned detection units 400 and 500 can be disposed on the surface of the optical waveguide 300 on the side where the coupling-in region 302 and the coupling-out region 303 are located (the side facing the human eye when used as AR glasses), or on the opposite side (the side away from the human eye when used as AR glasses). Alternatively, the detection units 400 and 500 can be disposed on both side surfaces of the optical waveguide 300. Accordingly, the grating structures in the first detection coupling-out region 304 and the second detection coupling-out region 305 will be designed accordingly to enable the image light to be coupled out in the corresponding directions. The specific design will depend on the needs of the actual application and is not limited here.

[0085] For the solution in this example, after the image light entering the optical waveguide 300 propagates a certain distance, the image light corresponding to the upper and lower parts of the image field of view will gradually separate. By setting a first detection decoupling area 304 at a specific position on the optical waveguide 300, and coordinating with the corresponding detection unit 400, the transmission characteristics of the diffraction optical waveguide can be used to detect the light in the upper and lower parts of the image field of view without expanding the target surface of the detection device; the first detection decoupling area 304 can further deflect the image light, so that the image light corresponding to the left and right parts of the image field of view gradually separates after deflection, then, by setting a second detection decoupling area 305 at a specific position on the optical waveguide 300, and coordinating with the corresponding detection unit 500, the light in the left and right parts of the image field of view can be detected, and there is also no need to expand the detection target surface of the detection device.

[0086] In addition, this method allows the detection process to occur on the optical waveguide 300. When applied to AR glasses, it can further avoid designing additional detection optical paths at other locations of the AR glasses, and also avoid the detection unit occupying other locations of the AR glasses, thereby facilitating the local miniaturization design of the AR glasses.

[0087] Of course, for the solution of the present application, in addition to detecting the tilt abnormality generated by the above-mentioned image, it is also possible to detect other types of morphological abnormalities generated by the image, such as: bending deformation of the image, image differences caused by scanning delays of the scanning light engine, etc., which will not be repeated here.

[0088] In other embodiments of the present application, the detection module in the present application solution can also be set in different forms. Figure 5 , shows a detection module 60 , which includes: two optical waveguides 600 and 700 forming a stacked structure, a detection unit 410 and a detection unit 510 .

[0089] The overall structures of optical waveguide 600 and optical waveguide 700 are similar, wherein optical waveguide 600 further includes a waveguide base 601, an incoupling region 602, an outcoupling region 603, and a detection outcoupling region 604. Optical waveguide 700 further includes a waveguide base 701, an incoupling region 702, an outcoupling region 703, and a detection outcoupling region 704. A significant structural difference between the two is that the detection outcoupling region 604 in optical waveguide 600 is located between the incoupling region 602 and the outcoupling region 603; whereas the position of the detection outcoupling region 704 in optical waveguide 700 is the same as that of the detection outcoupling region 104 in the optical waveguide 10 of the aforementioned embodiment, located to the right of the outcoupling region 703.

[0090] In some implementations, optical waveguides 600 and 700 form a stacked structure, and the fields of view corresponding to the image light coupled out of outcoupling regions 603 and 703 can be spliced, thereby increasing the overall field of view during display and the size of the displayed image. To this end, in some embodiments, the sub-fields of view corresponding to the image light propagating through optical waveguides 600 and 700 differ. In other embodiments, the sub-fields of view corresponding to the image light propagating through optical waveguides 600 and 700 are the same, but the wavelengths of the image light differ.

[0091] The complete image field of view is usually divided into two parts, which are coupled into the optical waveguide 600 and the optical waveguide 700 respectively. In this application, the image field of view coupled into the optical waveguide 600 can be referred to as the first field of view, and the corresponding image light can be referred to as the first field of view image light; the image field of view coupled into the optical waveguide 700 can be referred to as the second field of view, and the corresponding image light can be referred to as the second field of view image light.

[0092] Therefore, after the first field image light enters the optical waveguide 600 from the coupling-in region 602 , it propagates toward the coupling-out region 603 under the action of the coupling-in grating of the coupling-in region 602 and undergoes a certain degree of separation. Figure 5 6 shows the optical paths 64 and 65 corresponding to the separated image light, which respectively represent the image light of the upper and lower parts of the first field of view. After passing through the detection outcoupling area 604, the image light is received by the detection unit 410.

[0093] Correspondingly, the second field image light passes through the coupling-in region 602 of the optical waveguide 600, enters the optical waveguide 700 from the coupling-in region 702, and propagates toward the coupling-out region 703 under the action of the coupling-in grating of the coupling-in region 702, and undergoes a certain degree of separation. Figure 5 74 and 75 corresponding to the separated image light are shown in FIG. 74 , which represent the image light of the upper and lower parts of the second field of view, respectively. After passing through the outcoupling region 704 , the image light is received by the detection unit 510 .

[0094] In this example, the locations of the detection outcoupling regions 604 and 704 are also related to the optical path of the image light in the central field of view of the image. Specifically, the detection outcoupling region 604 is disposed on the optical path of the image light corresponding to the central field of view of the image in the first field of view, and is symmetrically arranged based on this optical path, so that the image light from the upper and lower parts of the first field of view both pass through the detection outcoupling region 604. The detection outcoupling region 704 is disposed on the optical path of the image light corresponding to the central field of view of the image in the second field of view, and is symmetrically arranged based on this optical path, so that the image light from the upper and lower parts of the second field of view both pass through the detection outcoupling region 704.

[0095] refer to Figure 6 , shows a detection module 80. It includes an optical waveguide 800 and a detection unit 420. Unlike the optical waveguides in the previous embodiments, optical waveguide 800 does not have a detection outcoupling region. Detection unit 420 is disposed at the edge of optical waveguide 800 to receive image light that continues to propagate within optical waveguide 800 after passing through outcoupling region 803.

[0096] In a preferred embodiment, the detection unit 420 is arranged symmetrically about the optical path of light corresponding to the central field of view of the image in the optical waveguide 800. The detection unit 420 further includes two detection areas 420a and 420b. The detection units 420 are arranged such that the detection areas are distributed along a first direction. Specifically, one detection area 420a of the detection unit 420 primarily receives image light from the upper half of the field of view, while the other detection area 420b primarily receives image light from the lower half of the field of view. This allows the detection unit 420 to detect image anomalies based on the difference in image light corresponding to the two fields of view.

[0097] The detection unit 420 can be fixed to the edge of the optical waveguide 800 by attaching. Of course, when used in AR glasses, the detection unit 420 can be set inside the frame. The specific requirements will depend on the actual application and are not specifically limited here.

[0098] Based on the optical waveguide described above, a near-eye display module is also provided in an embodiment of the present application. The near-eye display module can be applied to AR glasses. The near-eye display module includes: a light engine and the aforementioned detection module. The light engine is used to generate image light and project it onto the corresponding coupling-in area on the optical waveguide in the detection module. The image light can be transmitted in the optical waveguide and coupled out through the coupling-out area to achieve display; in addition, a part of the image light will continue to propagate in the optical waveguide, and the detection module can detect this part of the image light that continues to propagate in the optical waveguide.

[0099] Based on the above content, for the solution of the embodiment of the present application, on the one hand, after the image light entering the optical waveguide propagates a certain distance, the image light corresponding to different parts of the image field of view will gradually separate. By setting the detection coupling area and / or detection unit at a specific position on the optical waveguide, it is possible to detect the light in the upper and lower and / or left and right parts of the image field of view without expanding the detection target surface of the detection device; on the other hand, the detection process occurs on the optical waveguide. When applied to AR glasses, it can further avoid designing additional detection optical paths at other positions of the AR glasses, and also avoid the detection unit occupying other positions of the AR glasses, thereby facilitating the local miniaturization design of the AR glasses.

[0100] The expressions "first," "second," "the first," or "the second" used in various embodiments of the present disclosure may modify various components regardless of order and / or importance, but these expressions do not limit the corresponding components. The above expressions are only configured for the purpose of distinguishing an element from other elements.

[0101] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the above-mentioned inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A detection module, characterized in that: The detection module includes an optical waveguide and a detection unit; wherein, The optical waveguide at least comprises an incoupling region and an outcoupling region; The coupling-in region couples the image light into the optical waveguide and propagates a portion of the image light toward the coupling-out region; The outcoupling region is used to expand and propagate the image light and couple out a portion of the expanded image light; The detection unit performs detection based on the image light propagating in the optical waveguide.

2. The detection module according to claim 1, wherein: The optical waveguide further includes a detection outcoupling region, and the detection unit is arranged in conjunction with the detection outcoupling region.

3. The detection module according to claim 2, wherein: The detection outcoupling region is arranged on the optical path of the image light that continues to propagate in the waveguide matrix after passing through the outcoupling region, and the detection target surface of the detection unit is arranged toward the detection outcoupling region.

4. The detection module according to claim 3, wherein: The detection outcoupling region is symmetrically arranged based on an optical path of image light corresponding to a central field of view of the image.

5. The detection module according to claim 4, wherein: The detection outcoupling area includes at least two independent sub-areas, and the sub-areas are based on the optical path distribution of the image light corresponding to the central field of view of the image; The detection unit includes a detection subunit corresponding to the sub-area, and a detection target surface of the detection subunit is arranged toward the sub-area.

6. The detection module according to claim 2, wherein: The detection outcoupling area includes a first detection outcoupling area and a second detection outcoupling area, wherein: The first detection outcoupling region is arranged on an optical path of the image light that continues to propagate in the waveguide matrix after passing through the outcoupling region, and the first detection outcoupling region deflects a portion of the image light to the second detection outcoupling region; The second detection outcoupling region is arranged on the optical path of the image light deflected by the first detection outcoupling region; The detection unit includes a first detection unit and a second detection unit; The first detection unit is matched with the first detection outcoupling area, and the second detection unit is matched with the second detection outcoupling area.

7. The detection module according to claim 6, wherein: The first detection unit is arranged at a position such that a detection target surface in the first detection unit receives image light corresponding to the upper and lower parts of the image field coupled out by the first detection outcoupling area; The second detection unit is arranged at a position such that the detection target surface in the second detection unit receives the image light coupled out by the second detection outcoupling area and corresponding to the left and right parts of the image field.

8. The detection module according to claim 2, wherein: The optical waveguide comprises at least two stacked optical waveguide sheets, each of which is provided with at least one detection outcoupling region; The number of the detection units corresponds to the detection outcoupling region, and the detection units are located outside the optical waveguide and match the positions of the detection outcoupling region.

9. The detection module according to any one of claims 1, wherein: The detection unit is arranged at the edge of the optical waveguide and is located on the optical path of the image light that passes through the outcoupling region and continues to propagate in the optical waveguide.

10. A near-eye display module, characterized in that: The near-eye display module includes a light engine and the detection module described in any one of claims 1 to 9, wherein the light engine is used to generate image light, and the detection module performs display and detection based on the image light.

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