Optical waveguide

Abstract

The present invention provides an optical waveguide. The optical waveguide includes an optical waveguide plate; an input grating, the input grating couples light emitted by an external image source into the optical waveguide plate; a turning grating, the turning grating is used to receive light from the input grating, and the turning grating is located on one side of the input grating; an output grating, the output grating is used to receive light from the turning grating, and the output grating is located on one side of the turning grating, the line connecting the center of the input grating and the center of the turning grating is perpendicular to the line connecting the center of the output grating and the center of the turning grating, and the output grating couples light out of the optical waveguide plate; a detector, at least one detector is located on the side of the turning grating away from the input grating, so as to receive light in the turning grating that does not enter the output grating, and at least another detector is located on the side of the output grating away from the turning grating, so as to receive light in the output grating that is not used for imaging. The present invention solves the problem that the optical waveguide in the prior art is difficult to realize real-time detection and affects the imaging quality.

Description

Technical Field

[0001] The present invention relates to the technical field of diffraction optical equipment, and in particular to an optical waveguide. Background Art

[0002] With the continuous innovation of future technology, virtual reality (VR), augmented reality (AR), and mixed reality (MR) have gradually entered industries such as industrial education. In terms of AR augmented reality, optical waveguide technology is an indispensable step. However, there is currently no technology that can detect light problems in optical waveguides in real time, and it is impossible to synchronously detect the problem of overflow light during coupling out of the optical waveguide, and it is impossible to timely feedback to the original port for optical compensation, making it difficult to ensure imaging quality.

[0003] In other words, the optical waveguide in the prior art has the problem of being difficult to achieve real-time detection and affecting the imaging quality. Summary of the invention

[0004] The main purpose of the present invention is to provide an optical waveguide to solve the problem that the optical waveguide in the prior art is difficult to achieve real-time detection and affects the imaging quality.

[0005] In order to achieve the above-mentioned purpose, the present invention provides an optical waveguide, comprising: an optical waveguide plate; an in-coupling grating, which is arranged on the optical waveguide plate and couples light emitted by an external image source into the optical waveguide plate; a turning grating, which is used to receive light from the in-coupling grating and is located on one side of the in-coupling grating; an out-coupling grating, which is used to receive light from the turning grating and is located on one side of the turning grating; a out-coupling grating, which is used to receive light from the turning grating and is located on one side of the turning grating, a line connecting the center of the in-coupling grating and the center of the turning grating is perpendicular to a line connecting the center of the out-coupling grating and the center of the turning grating, and the out-coupling grating couples light out of the optical waveguide plate; and a plurality of detectors, at least one detector being located on a side of the turning grating away from the in-coupling grating to receive light that does not enter the out-coupling grating, and at least another detector being located on a side of the out-coupling grating away from the turning grating to receive light that is not used for imaging in the out-coupling grating.

[0006] Furthermore, the detector is spaced apart from the optical waveguide sheet, the optical waveguide further comprises a plurality of slit gratings, the slit gratings are arranged on the optical waveguide sheet, the slit gratings and the detectors are arranged in one-to-one correspondence, and the slit gratings are located in the light incident direction of the detectors.

[0007] Furthermore, the detector is arranged on the optical waveguide sheet.

[0008] Further, a plurality of detectors are arranged on the same side surface of the optical waveguide plate; or at least two detectors are arranged on different surfaces of the optical waveguide plate.

[0009] Further, the incoupling grating is a diffraction grating.

[0010] Furthermore, a period of the diffraction grating is greater than or equal to 300 nanometers and less than or equal to 600 nanometers.

[0011] Furthermore, the optical waveguide sheet is made of glass.

[0012] Furthermore, the thickness of the optical waveguide sheet is greater than or equal to 400 micrometers and less than or equal to 1 millimeter.

[0013] Furthermore, the outcoupling grating is one of a blazed grating, a tilted grating, and a rectangular grating.

[0014] Further, the detector is a CMOS detector.

[0015] According to the technical solution of the present invention, the optical waveguide includes an optical waveguide plate, an in-coupling grating, a turning grating, an out-coupling grating and a detector. The in-coupling grating is arranged on the optical waveguide plate, and the in-coupling grating couples light emitted by an external image source into the optical waveguide plate; the turning grating is used to receive light from the in-coupling grating, and the turning grating is located on one side of the in-coupling grating; the out-coupling grating is used to receive light from the turning grating, and the out-coupling grating is located on one side of the turning grating, a line connecting the center of the in-coupling grating and the center of the turning grating is perpendicular to a line connecting the center of the out-coupling grating and the center of the turning grating, and the out-coupling grating couples light out of the optical waveguide plate; there are a plurality of detectors, at least one detector is located on a side of the turning grating away from the in-coupling grating, so as to receive light in the turning grating that does not enter the out-coupling grating, and at least another detector is located on a side of the out-coupling grating away from the turning grating, so as to receive light in the out-coupling grating that is not used for imaging.

[0016] By setting the coupling-in grating on the optical waveguide sheet, most of the light emitted by the external image source can be coupled into the optical waveguide sheet, thereby ensuring the coupling-in efficiency of the optical waveguide sheet. The turning grating is located on one side of the coupling-in grating. This arrangement enables most of the light coupled into the grating to be injected into the turning grating for amplification of the light by the turning grating, thereby ensuring that the turning grating can work stably. The coupling-out grating is located on one side of the turning grating. The line connecting the center of the coupling-in grating and the center of the turning grating is perpendicular to the line connecting the center of the coupling-out grating and the center of the turning grating. This arrangement enables most of the effective light in the turning grating to be injected into the coupling-out grating for coupling out the light by the coupling-out grating, thereby ensuring the coupling-out efficiency of the optical waveguide sheet, thereby ensuring the imaging quality of the optical waveguide sheet. At least one detector is located on the side of the turning grating away from the coupling-in grating. This arrangement enables most of the light in the turning grating that does not enter the coupling-out grating to be injected into the detector, thereby facilitating the detector to detect the light in the turning grating that does not enter the coupling-out grating in real time. At least one other detector is located on a side of the outcoupling grating away from the turning grating. This arrangement allows most of the light in the outcoupling grating that is not used for imaging to enter the detector, which is beneficial for the detector to perform real-time detection of the light in the outcoupling grating that is not used for imaging.

[0017] In addition, since not all light in the optical waveguide sheet enters the human eye, detectors can be set at different positions. In the present invention, detectors are set in two directions, one is to set the detector on the side of the turning grating away from the coupling-in grating, and the other is to set the detector on the side of the coupling-out grating away from the turning grating. By setting the detectors in two directions, it is greatly ensured that the detectors can perform real-time detection of the light in the optical waveguide sheet that is not used for imaging, thereby improving the detection efficiency of the detectors and ensuring the imaging quality of the optical waveguide sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 A schematic structural diagram of a first embodiment of the optical waveguide of the present invention is shown;

[0020] Figure 2 A schematic structural diagram of a second embodiment of the optical waveguide of the present invention is shown;

[0021] Figure 3 FIG. 1 is a schematic structural diagram of a third embodiment of the optical waveguide of the present invention.

[0022] The above drawings include the following reference numerals:

[0023] 10. Optical waveguide; 11. In-coupling grating; 12. Turning grating; 13. Out-coupling grating; 14. Slit grating; 20. Detector. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0026] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0027] In order to solve the problem that the optical waveguide in the prior art is difficult to realize real-time detection and affects the imaging quality, the present invention provides an optical waveguide.

[0028] like Figures 1 to 3 As shown in FIG. 1 , the optical waveguide includes an optical waveguide plate 10, an in-coupling grating 11, a turning grating 12, an out-coupling grating 13 and a detector 20. The in-coupling grating 11 is arranged on the optical waveguide plate 10, and the in-coupling grating 11 couples light emitted by an external image source into the optical waveguide plate 10; the turning grating 12 is used to receive the light of the in-coupling grating 11, and the turning grating 12 is located on one side of the in-coupling grating 11; the out-coupling grating 13 is used to receive the light of the turning grating 12, and the out-coupling grating 13 is located on one side of the turning grating 12, and the center of the in-coupling grating 11 is The line connecting the center of the optical waveguide 10 and the center of the turning grating 12 is perpendicular to the line connecting the center of the out-coupling grating 13 and the center of the turning grating 12, and the out-coupling grating 13 couples the light out of the optical waveguide 10; there are multiple detectors 20, at least one detector 20 is located on the side of the turning grating 12 away from the coupling-in grating 11, so as to receive the light in the turning grating 12 that does not enter the out-coupling grating 13, and at least another detector 20 is located on the side of the out-coupling grating 13 away from the turning grating 12, so as to receive the light in the out-coupling grating 13 that is not used for imaging.

[0029] By arranging the coupling-in grating 11 on the optical waveguide plate 10, most of the light emitted by the external image source can be coupled into the optical waveguide plate 10, thereby ensuring the coupling-in efficiency of the optical waveguide plate 10. The turning grating 12 is located on one side of the coupling-in grating 11. This arrangement enables most of the light coupled into the grating 11 to be injected into the turning grating 12 for amplification of the light by the turning grating 12, thereby ensuring that the turning grating 12 can work stably. The coupling-out grating 13 is located on one side of the turning grating 12. The line connecting the center of the coupling-in grating 11 and the center of the turning grating 12 is perpendicular to the line connecting the center of the coupling-out grating 13 and the center of the turning grating 12. This arrangement enables most of the effective light in the turning grating 12 to be injected into the coupling-out grating 13 for coupling out the light by the coupling-out grating 13, thereby ensuring the coupling-out efficiency of the optical waveguide plate 10, thereby ensuring the imaging quality of the optical waveguide plate 10. At least one detector 20 is located on a side of the turning grating 12 away from the coupling-in grating 11, so that most of the light in the turning grating 12 that does not enter the coupling-out grating 13 can be incident on the detector 20, which is beneficial for the detector 20 to perform real-time detection of the light in the turning grating 12 that does not enter the coupling-out grating 13. At least another detector 20 is located on a side of the coupling-out grating 13 away from the turning grating 12, so that most of the light in the coupling-out grating 13 that is not used for imaging can be incident on the detector 20, which is beneficial for the detector 20 to perform real-time detection of the light in the coupling-out grating 13 that is not used for imaging.

[0030] It should be noted that the turning grating 12 and the coupling-out grating 13 are both arranged on the optical waveguide sheet 10, so that the turning grating 12 receives the light coupled into the grating 11, and the coupling-out grating 13 receives the light from the turning grating 12. The coupling-in grating 11 couples the light into the optical waveguide sheet, the coupling-out grating 13 couples the light in the optical waveguide sheet out to the external environment, and the turning grating 12 couples the light at the coupling-in grating 11 into the coupling-out grating 13.

[0031] In addition, since not all light in the optical waveguide sheet 10 enters the human eye, the detector 20 can be set at different positions. In the present invention, the detector 20 is set at two positions, one is to set the detector 20 at the side of the turning grating 12 away from the coupling-in grating 11, and the other is to set the detector 20 at the side of the coupling-out grating 13 away from the turning grating 12. By setting the detector 20 in two directions, it is greatly ensured that the detector 20 can perform real-time detection of the light in the optical waveguide sheet 10 that is not used for imaging, thereby improving the detection efficiency of the detector 20 and ensuring the imaging quality of the optical waveguide sheet 10.

[0032] It should be noted that the above-mentioned turning grating 12 and coupling-out grating 13 can be designed separately or as one. As the light propagates in the optical waveguide sheet 10, the optical waveguide sheet 10 expands the received light into at least one dimension, so that the light propagates in at least one direction. The above-mentioned detector 20 is used to detect the intensity of the light field inside the optical waveguide sheet 10, and this intensity affects the quality of the image that finally enters the human field of vision. On this basis, a standard reference value of the light field intensity can be set. If it is detected that the light field intensity is lower than the reference value, the energy can be increased at the light source in time to enhance the intensity of the light field entering the optical waveguide sheet 10; if the detected value is higher than the reference value, the light source is adjusted to reduce the intensity. In this way, the light field inside the optical waveguide sheet 10 can be detected in real time and compensation and adjustment can be made in time according to the detection results, thereby ensuring the imaging quality of the optical waveguide sheet 10.

[0033] By detecting the light not used for imaging through multiple detectors 20, the position and strength of the light intensity signals on the multiple detectors 20 are analyzed to determine which position of the grating is working abnormally, so as to pre-compensate the image impact caused by the defect by adjusting the image source to ensure the imaging quality.

[0034] Embodiment 1

[0035] like Figure 1In the specific embodiment shown, the detector 20 is arranged at intervals from the optical waveguide sheet 10, and the optical waveguide further includes a plurality of slit gratings 14, which are arranged on the optical waveguide sheet 10, and are arranged one-to-one with the detectors 20, and are located in the light incident direction of the detectors 20. The slit gratings 14 are arranged on the optical waveguide sheet 10, and are arranged one-to-one with the detectors 20, and are located in the light incident direction of the detectors 20. Such an arrangement enables most of the light in the turning grating 12 that does not enter the decoupling grating 13 and the light in the decoupling grating 13 that is not used for imaging to enter the slit grating 14 and be coupled out from the slit grating 14 to the one-to-one corresponding detectors 20, so that the detectors 20 can perform real-time detection of the light field inside the optical waveguide sheet 10 and timely compensation and adjustment according to the detection results, thereby ensuring the imaging quality of the optical waveguide sheet 10.

[0036] Specifically, the coupling grating 11 is a diffraction grating. The coupling grating 11 is a diffraction grating, which ensures that the light emitted by the external image source can be totally reflected in the diffraction grating, so that most of the light emitted by the external image source can be coupled into the optical waveguide 10, ensuring the coupling efficiency of the coupling grating 11.

[0037] Specifically, the period of the diffraction grating is greater than or equal to 300 nanometers and less than or equal to 600 nanometers. Limiting the period of the diffraction grating to the range of 300 nanometers to 600 nanometers ensures that the light emitted by the external image source can be totally reflected in the diffraction grating, so that most of the light emitted by the external image source can be coupled into the optical waveguide sheet 10, ensuring that the coupling grating 11 can work stably.

[0038] In addition, the material of the optical waveguide sheet 10 is glass. The material of the optical waveguide sheet 10 is glass, which is conducive to the transmission of light inside the optical waveguide sheet 10 and reduces the production cost of the optical waveguide sheet 10. It should be noted that the above-mentioned glass is high-refractive index glass, which can effectively increase the field of view of the optical waveguide sheet 10 and improve the imaging quality of the optical waveguide sheet 10. Similarly, optical waveguide sheets 10 of different materials can be selected according to actual needs.

[0039] Optionally, the thickness of the optical waveguide sheet 10 is greater than or equal to 400 microns and less than or equal to 1 millimeter. If the thickness of the optical waveguide sheet 10 is less than 400 microns, the optical waveguide sheet 10 is difficult to manufacture, which increases the difficulty of processing the optical waveguide sheet 10. At the same time, the optical waveguide sheet 10 is prone to breakage during use, which reduces the structural strength of the optical waveguide sheet 10. If the thickness of the optical waveguide sheet 10 is greater than 1 millimeter, the thickness of the optical waveguide sheet 10 is too large, which is not conducive to the miniaturization of the optical waveguide sheet 10. Limiting the thickness of the optical waveguide sheet 10 to a range of 400 microns to 1 millimeter ensures the miniaturization of the optical waveguide sheet 10 while ensuring the structural strength of the optical waveguide sheet 10.

[0040] Optionally, the outcoupling grating 13 is one of a blazed grating, a tilted grating, and a rectangular grating. The outcoupling grating 13 is one of a blazed grating, a tilted grating, and a rectangular grating. This configuration allows different gratings to be used according to different application requirements. The grating can couple out the light field information, and the specific parameters can be adjusted to adjust the uniformity of the outcoupling light field to meet different application requirements, thereby ensuring that the outcoupling grating 13 can couple out the imaging light to the human eye while enhancing the versatility of the optical waveguide sheet 10.

[0041] It should be noted that the blazed grating is a grating with blazed characteristics in which the groove surface is not parallel to the grating normal, that is, there is a small angle between the two. The sawtooth grating is the most ideal blazed grating, and the sawtooth grating has a sawtooth structure on its cross section for diffraction. The tilted grating is a grating in which the plane of the grating is at a certain inclination angle with the grating tangent. The rectangular grating is a grating in which the cross section is a rectangular structure for diffraction.

[0042] Specifically, the detector 20 is a CMOS detector. The detector 20 is a CMOS detector, and this arrangement ensures that the CMOS detector can detect the light field changes in the optical waveguide plate 10 in real time, thereby detecting whether the structure in the grating is normal, so that timely compensation and adjustment can be made to ensure the imaging quality of the optical waveguide plate 10.

[0043] Embodiment 2

[0044] The difference from the first embodiment is that the position of the detector 20 is different.

[0045] exist Figure 2 In the specific embodiment shown, the optical waveguide sheet 10 is not provided with the slit grating 14, and the detector 20 is provided on the optical waveguide sheet 10. This arrangement enables the optical waveguide sheet 10 and the detector 20 to be integrally formed, so that the detector 20 can perform real-time detection of the light in the optical waveguide sheet 10 that is not used for imaging, and at the same time, the volume of the optical waveguide is reduced, thereby ensuring the miniaturization of the optical waveguide.

[0046] like Figure 2As shown, a plurality of detectors 20 are arranged on the same side surface of the optical waveguide plate 10. At least a part of the coupling-in grating 11, the turning grating 12 and the coupling-out grating 13 are on the same surface, and when the plurality of detectors 20 are arranged on the same side surface of the optical waveguide plate 10, the plurality of detectors 20 need to be on the same surface as the coupling-in grating 11, the turning grating 12 and the coupling-out grating 13, so that at least one detector 20 can receive the light in the turning grating 12 that does not enter the coupling-out grating 13, and at least another detector 20 can receive the light in the coupling-out grating 13 that is not used for imaging. Through the detection of the light that is not used for imaging by the plurality of detectors 20, the position and strength of the light intensity signals on the plurality of detectors 20 are analyzed to determine which position of the grating is working abnormally, so as to pre-compensate the image influence caused by the defect by adjusting the image source, so as to ensure the imaging quality.

[0047] Embodiment 3

[0048] The difference from the second embodiment is that the position of the detector 20 is different.

[0049] exist Figure 3 In the specific embodiment shown, at least two detectors 20 are arranged on different surfaces of the optical waveguide plate 10. The two detectors 20 are arranged on different surfaces of the optical waveguide plate 10 so that the two detectors 20 receive light at different positions.

[0050] exist Figure 3 In the specific embodiment shown, at least a portion of the coupling-in grating 11, the turning grating 12 and the coupling-out grating 13 are on the same surface, and the two detectors 20 are located on both sides of the plane where the coupling-in grating 11, the turning grating 12 and the coupling-out grating 13 are located. Figure 3 In the specific embodiment shown, the optical waveguide plate 10 is a rectangular parallelepiped, the plane where the coupling-in grating 11, the turning grating 12 and the coupling-out grating 13 are located is the main plane, and the two detectors 20 are respectively arranged on two side surfaces connected to the main plane, and one detector 20 is arranged on the side away from the coupling-in grating 11, and the other detector 20 is arranged on the side away from the turning grating 12.

[0051] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0052] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0053] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An optical waveguide, characterized in that: include: Optical waveguide sheet (10); A coupling grating (11), wherein the coupling grating (11) is arranged on the optical waveguide plate (10), and the coupling grating (11) couples light emitted by an external image source into the optical waveguide plate (10); A turning grating (12), the turning grating (12) being used to receive light from the coupling-in grating (11), the turning grating (12) being located on one side of the coupling-in grating (11); an outcoupling grating (13), the outcoupling grating (13) being used to receive light from the turning grating (12), the outcoupling grating (13) being located on one side of the turning grating (12), the line connecting the center of the incoupling grating (11) and the center of the turning grating (12) being perpendicular to the line connecting the center of the outcoupling grating (13) and the center of the turning grating (12), and the outcoupling grating (13) coupling the light out of the optical waveguide plate (10); A detector (20), wherein the detector (20) is multiple, at least one of the detectors (20) is located on a side of the turning grating (12) away from the coupling-in grating (11), and is used to receive light in the turning grating (12) that does not enter the coupling-out grating (13), and at least another of the detectors (20) is located on a side of the coupling-out grating (13) away from the turning grating (12), and is used to receive light in the coupling-out grating (13) that is not used for imaging, and the detector (20) is used to detect the light field intensity inside the optical waveguide plate (10).

2. The optical waveguide according to claim 1, characterized in that The detector (20) is arranged at an interval from the optical waveguide plate (10); the optical waveguide further comprises a plurality of slit gratings (14); the slit gratings (14) are arranged on the optical waveguide plate (10); the slit gratings (14) and the detectors (20) are arranged in a one-to-one correspondence; the slit gratings (14) are located in the light incident direction of the detector (20).

3. The optical waveguide according to claim 1, characterized in that The detector (20) is arranged on the optical waveguide plate (10).

4. The optical waveguide according to claim 3, characterized in that A plurality of the detectors (20) are arranged on the same side surface of the optical waveguide plate (10); or At least two of the detectors (20) are arranged on different surfaces of the optical waveguide plate (10).

5. The optical waveguide according to any one of claims 1 to 4, characterized in that The coupling-in grating (11) is a diffraction grating.

6. The optical waveguide according to claim 5, characterized in that The period of the diffraction grating is greater than or equal to 300 nanometers and less than or equal to 600 nanometers.

7. The optical waveguide according to any one of claims 1 to 4, characterized in that The material of the optical waveguide sheet (10) is glass.

8. The optical waveguide according to any one of claims 1 to 4, characterized in that The thickness of the optical waveguide sheet (10) is greater than or equal to 400 micrometers and less than or equal to 1 millimeter.

9. The optical waveguide according to any one of claims 1 to 4, characterized in that The outcoupling grating (13) is one of a blazed grating, a tilted grating and a rectangular grating.

10. The optical waveguide according to any one of claims 1 to 4, characterized in that The detector (20) is a CMOS detector.

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