Grating detection method and equipment

Abstract

The invention relates to a grating detection method and equipment, and the method comprises the steps: controlling a first movement mechanism to move under the condition that a light source device emits incident light to a first to-be-detected region of a to-be-detected grating on an optical waveguide, and driving a bearing platform for placing the optical waveguide to move in a first direction and rotate around the first direction, the first direction is perpendicular to the plane, where the optical waveguide is placed, of the bearing table until the intensity of diffracted light, received by the detection device, of the first to-be-detected area meets the preset requirement; the detection device is controlled to be aligned with the first to-be-detected area for scanning, and scanning data corresponding to the diffraction light of the first to-be-detected area are obtained; obtaining a diffraction pattern according to the scanning data corresponding to the diffraction light of the first to-be-detected area; under the condition that a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first to-be-detected area, it is determined that manufacturing defects appear in the first to-be-detected area, and distribution of the specific diffraction bright band is different from distribution of diffraction bright bands in the diffraction pattern when the to-be-detected grating does not have the manufacturing defects.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of optical detection technology, and more specifically, to an optical detection method and device. Background Art

[0002] Augmented Reality (AR) devices use micro-nano optical elements to project images generated by a projection machine into the human eye, so as to integrate virtual information with real images to achieve the purpose of augmented reality. The imaging system of AR devices must maintain high transmittance, and related technologies usually use diffraction waveguides to achieve high-quality imaging effects. Diffraction waveguides use a thin and transparent glass substrate or resin substrate, and are combined with coupling gratings and coupling gratings to allow light to be fully reflected and propagated in the waveguide and finally reach the human eye.

[0003] Surface relief grating waveguide (SRG) is one of the commonly used diffraction waveguides, and its manufacturing process includes electron beam lithography and nanoimprinting. Electron beam lithography (EBL) has the advantage of extremely high resolution and can prepare any pattern without a mask. It is often used to make the grating master mold used for diffraction waveguides. Nanoimprint Lithography (NIL) can achieve large-area, precision mass production of diffraction waveguides, which can meet the production capacity and yield requirements of consumer-level. NIL includes processes such as wafer cleaning, spin coating, imprinting, curing, and demolding, and finally forms a periodically arranged imprinted glue grating on the waveguide substrate.

[0004] Deviations introduced in the two manufacturing processes of electron beam lithography and nanoimprinting will inevitably produce grating manufacturing defects, such as periodic changes in grating line width, grating depth, and grating period at certain distances, or rough grating line edges caused by reduced graphic fidelity and structural collapse. When light is incident on a grating with these manufacturing defects, it will generate specific direction or random stray light that enters the optical waveguide for total reflection propagation, and finally couples out through the coupling grating into the human eye, greatly reducing the imaging effect of the product. Therefore, it is necessary to test and characterize grating manufacturing defects to evaluate their impact on product imaging.

[0005] At present, the commonly used measurement technologies for grating manufacturing defects include scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), etc. These technologies have high measurement accuracy and high resolution and can measure the micro-nanostructure defects of gratings. However, they are all destructive tests that destroy samples and cannot quantitatively characterize grating manufacturing defects.

[0006] Public Content

[0007] One object of the present disclosure is to provide a new technical solution for a grating detection method.

[0008] According to a first aspect of the present disclosure, a grating detection method is provided, comprising:

[0009] When the light source device emits incident light to a first test area of ​​the test grating set on the optical waveguide, the first motion mechanism is controlled to move, so as to drive the carrier on which the optical waveguide is placed to move along a first direction and rotate around the first direction until the intensity of the diffracted light of the first test area received by the detection device reaches a preset requirement, wherein the first direction is perpendicular to the plane on which the optical waveguide is placed on the carrier;

[0010] Controlling the detection device to scan the first area to be measured to obtain scanning data corresponding to the diffracted light of the first area to be measured;

[0011] Obtaining a diffraction pattern of the diffracted light of the first area to be measured according to scanning data corresponding to the diffracted light of the first area to be measured;

[0012] When a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first area to be measured, it is determined that a manufacturing defect occurs in the first area to be measured, and the distribution of the specific diffraction bright band is different from the distribution of the diffraction bright band in the diffraction pattern when the grating to be measured has no manufacturing defect.

[0013] Optionally, the method further includes:

[0014] In a case where the specific diffraction bright band is a periodically distributed diffraction bright band, determining that a periodic manufacturing error exists in the first to-be-tested area;

[0015] In a case where the specific diffraction bright band is a randomly distributed diffraction bright band, it is determined that a non-periodic manufacturing error exists in the first to-be-tested area.

[0016] Optionally, when the specific diffraction bright band is a periodically distributed diffraction bright band, the method further includes:

[0017] Obtaining diffraction angles corresponding to two adjacent levels of diffraction light of a specific wavelength from the periodically distributed diffraction bright bands;

[0018] The manufacturing error period of the first area to be measured is determined according to the wavelength value of the specific wavelength and the diffraction angles corresponding to two adjacent orders of diffraction light.

[0019] Optionally, the grating to be tested is an in-coupled grating or an out-coupled grating, and in the case that the in-coupled grating and / or the out-coupled grating has a manufacturing defect, the method further includes:

[0020] The light source device emits incident light, and when the incident light is incident on the coupling-in grating, the first motion mechanism is controlled to move, so as to drive the carrier platform on which the optical waveguide is placed to move and / or rotate, until the intensity of the diffracted light of the coupling-out grating received by the detection device reaches a preset requirement;

[0021] Controlling the detection device to scan the out-coupling grating to obtain scanning data corresponding to the diffracted light of the out-coupling grating;

[0022] Obtaining a diffraction pattern of the diffracted light of the out-coupling grating according to the scanning data corresponding to the diffracted light of the out-coupling grating, wherein the diffraction pattern of the diffracted light of the out-coupling grating has a specific diffraction bright band;

[0023] Obtaining a first diffraction intensity according to a specific diffraction bright band appearing in the diffraction pattern of the diffracted light of the outcoupling grating;

[0024] Obtaining a second diffraction intensity, wherein the second diffraction intensity is determined based on a diffraction bright band in a diffraction pattern when both the coupling-in grating and the coupling-out grating have no manufacturing defects;

[0025] Determining an imaging quality influence degree value corresponding to a grating manufacturing error according to the first diffraction intensity and the second diffraction intensity;

[0026] According to the imaging quality influence degree value, the influence result of the manufacturing defects of the coupling-in grating and / or the coupling-out grating arranged on the optical waveguide on the imaging quality is determined.

[0027] Optionally, after completing the detection of the first to-be-tested area of ​​the to-be-tested grating, the method further includes:

[0028] Controlling the movement of the first motion mechanism to drive the carrier on which the optical waveguide is placed to move along the second direction and / or the third direction, so that the incident light emitted by the light source device is directed toward the second area to be measured of the grating to be measured, wherein the first direction, the second direction and the third direction are perpendicular to each other;

[0029] Controlling the detection device to scan the second area to be measured to obtain scanning data corresponding to the diffracted light of the second area to be measured;

[0030] Obtaining a diffraction pattern of the diffracted light of the second area to be measured according to the scanning data corresponding to the diffracted light of the second area to be measured;

[0031] When a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the second test area, it is determined that a manufacturing defect occurs in the second test area, and the distribution of the specific diffraction bright band is different from the diffraction bright band in the diffraction pattern when the test grating is defect-free.

[0032] Optionally, the controlling the detection device to scan the first area to be measured to obtain scanning data corresponding to the diffracted light of the first area to be measured includes:

[0033] The control detection device is aligned with the first area to be measured and scans within a set scanning plane to obtain scanning data corresponding to the diffracted light of the first area to be measured, wherein the set scanning plane is a plane determined based on the incident direction of the incident light and the first direction.

[0034] Optionally, controlling the first motion mechanism to move, driving the carrier on which the optical waveguide is placed to move along a first direction and rotate around the first direction, until the intensity of the diffracted light of the first area to be measured received by the detection device reaches a preset requirement, comprises:

[0035] Controlling the first motion mechanism to move, driving the carrier on which the optical waveguide is placed to move along a first direction, until the intensity of the diffracted light from the first area to be measured received by the detection device reaches a first preset requirement;

[0036] The first motion mechanism is controlled to move, so as to drive the support platform on which the optical waveguide is placed to rotate along a first direction until the intensity of the diffracted light from the first area to be measured received by the detection device reaches a second preset requirement.

[0037] According to a second aspect of the present disclosure, a grating detection device is provided, comprising: a control device, a light source device, a detection device, a carrier platform and a first motion mechanism; wherein,

[0038] The control device is used for controlling the first motion mechanism to move when the light source device emits incident light to a first to-be-measured area of ​​the to-be-measured grating disposed on the optical waveguide, so as to drive the carrier on which the optical waveguide is placed to move along a first direction and rotate around the first direction until the intensity of the diffracted light of the first to-be-measured area received by the detection device reaches a preset requirement, wherein the first direction is perpendicular to the plane on which the optical waveguide is placed on the carrier;

[0039] Controlling the detection device to scan the first area to be measured to obtain scanning data corresponding to the diffracted light of the first area to be measured;

[0040] Obtaining a diffraction pattern of the diffracted light of the first area to be measured according to scanning data corresponding to the diffracted light of the first area to be measured;

[0041] When a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first area to be measured, it is determined that a manufacturing defect occurs in the first area to be measured, and the distribution of the specific diffraction bright band is different from the distribution of the diffraction bright band in the diffraction pattern when the grating to be measured has no manufacturing defect.

[0042] Optionally, the device further includes a second motion mechanism and a third motion mechanism; wherein,

[0043] The control device is used to control the movement of the second motion mechanism to drive the light source device to emit incident light at different angles;

[0044] The control device is used to control the movement of the third motion mechanism to drive the detection device to receive diffracted light at different angles.

[0045] Optionally, in the case of detecting whether a coupling-in grating or a coupling-out grating arranged on the optical waveguide has a manufacturing defect based on the grating detection device, the light source device and the detection device are located on the same side of the optical waveguide;

[0046] When the grating detection device is used to detect the influence of a coupling-in grating with manufacturing defects or an out-coupling grating with manufacturing defects on the imaging of the optical waveguide, and the optical waveguide is a reflective optical structure, the light source device and the detection device are located on the same side of the optical waveguide; when the grating detection device is used to detect the influence of a coupling-in grating with manufacturing defects or an out-coupling grating with manufacturing defects on the imaging of the optical waveguide, and the optical waveguide is a transmissive optical structure, the light source device and the detection device are located on different sides of the optical waveguide.

[0047] The optical detection method provided by the present disclosure, on the one hand, realizes non-destructive detection of gratings and improves the detection efficiency and accuracy of gratings; on the other hand, it can change the incident angle of the light source device and the receiving angle of the detection device to detect different areas of the grating to be measured, and the detection flexibility is high.

[0048] Features and advantages of the embodiments of the present specification will become apparent from the following detailed description of exemplary embodiments of the present specification with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the specification and, together with the description, serve to explain the principles of the embodiments of the specification.

[0050] Figure 1 is a processing flow chart of a grating detection method according to an embodiment of the present invention.

[0051] Figure 2 is a schematic diagram of a diffraction intensity curve according to an embodiment of the present invention.

[0052] Figure 3 Schematic diagram of the structure of a grating detection device according to an embodiment of the present invention.

[0053] Figure 4 Schematic diagram of the structure of a grating detection device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0054] Various exemplary embodiments of the present specification will now be described in detail with reference to the accompanying drawings.

[0055] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the embodiments of the present specification and its application or uses.

[0056] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0057] In order to solve the above technical problems, an embodiment of the present invention provides a grating detection method, according to Figure 1 As shown, the grating detection method may include the following steps S110 to S140.

[0058] Step S110, when the light source device emits incident light to the first area to be measured of the grating to be measured set on the optical waveguide, the first motion mechanism is controlled to move, driving the support platform on which the optical waveguide is placed to move along the first direction and rotate around the first direction until the intensity of the diffracted light received by the detection device in the first area to be measured reaches a preset requirement, wherein the first direction is perpendicular to the plane on which the optical waveguide is placed on the support platform.

[0059] The grating to be measured is an in-coupled grating or an out-coupled grating.

[0060] The light source device includes a laser and a polarization optical element. The laser is a broad spectrum light source. The polarization optical element is used to adjust the polarization state and emission intensity of the laser. The light source device can move or rotate under the drive of a motion mechanism to emit incident light in different directions.

[0061] The platform is provided with a test fixture. The test fixture is used to fix the optical waveguide so that when the platform moves or rotates, the optical waveguide remains stationary relative to the platform. The test fixture can be adapted to optical waveguides of different shapes and sizes.

[0062] The first motion mechanism can drive the bearing platform to rotate around a first direction and move along a first direction, a second direction and a third direction. The first direction, the second direction and the third direction are all perpendicular to each other.

[0063] The detection device includes a spectrometer. The spectrometer has a wide spectrum collection capability. The detection device can move or rotate under the drive of a motion mechanism to collect diffracted light at different angles.

[0064] In some embodiments, step S110 specifically includes the following steps S111 to S112.

[0065] Step S111, controlling the first motion mechanism to move, driving the support platform on which the optical waveguide is placed to move along the first direction, until the intensity of the diffracted light from the first area to be measured received by the detection device reaches a first preset requirement.

[0066] Step S112, controlling the first motion mechanism to move, driving the support platform on which the optical waveguide is placed to rotate along the first direction, until the intensity of the diffracted light from the first area to be measured received by the detection device reaches a second preset requirement.

[0067] The purpose of step S111 is to adjust the height of the support platform so that the intensity of the diffracted light received by the detection device in the first area to be detected reaches the maximum. At this time, the intensity of the diffracted light reaches the maximum when other factors affecting the intensity of the diffracted light remain unchanged and only the height of the support platform is changed.

[0068] The purpose of step S112 is to match the orientation of the grating to be measured so that the intensity of the diffracted light received by the detection device in the first area to be measured reaches the maximum. The orientation of the grating is the arrangement direction of the grating stripes. At this time, the intensity of the diffracted light reaches the maximum when other factors affecting the intensity of the diffracted light remain unchanged and reach the maximum in the process of matching the orientation of the grating.

[0069] Step S120, controlling the detection device to scan the first area to be measured, and obtaining scanning data corresponding to the diffracted light of the first area to be measured.

[0070] In some embodiments, the detection device is controlled to align with the first area to be measured, and scans within a set scanning plane to obtain scanning data corresponding to the diffracted light of the first area to be measured. The scanning plane is set to be a plane determined based on the incident direction of the incident light and the first direction. The detection device scans within the set scanning plane, and the diffracted light data of the first area to be measured can be quickly obtained, thereby improving the measurement efficiency.

[0071] Step S130, obtaining a diffraction pattern of the diffracted light in the first area to be measured according to the scanning data corresponding to the diffracted light in the first area to be measured.

[0072] The scanning data includes diffraction intensity data of diffracted light at different angles received by the detection device.

[0073] Step S140, when a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first test area, it is determined that a manufacturing defect occurs in the first test area, wherein the distribution of the specific diffraction bright band is different from the distribution of the diffraction bright band in the diffraction pattern when the test grating is defect-free.

[0074] When the grating to be tested has no manufacturing defects, there is a bright diffraction band in the diffraction pattern.

[0075] The grating detection method provided by the embodiment of the present invention, on the one hand, realizes non-destructive detection of the grating and improves the detection efficiency and accuracy of the grating; on the other hand, it can change the incident angle of the light source device and the receiving angle of the detection device to detect different areas of the grating to be measured, and the detection flexibility is high.

[0076] In some embodiments, the method further includes: when the specific diffraction bright band is a periodically distributed diffraction bright band, determining that the first area to be tested has a periodic manufacturing error; when the specific diffraction bright band is a randomly distributed diffraction bright band, determining that the first area to be tested has a non-periodic manufacturing error. According to the distribution of the specific diffraction bright band, the type of error occurring in the first area to be tested can be determined.

[0077] Periodic manufacturing errors are errors that occur during the grating manufacturing process and are periodic. Non-periodic manufacturing errors are errors that occur during the grating manufacturing process and are random or accidental errors.

[0078] In the case where there is a periodic manufacturing error in the first area to be measured, a diffraction intensity curve of a specific wavelength is extracted from the periodically distributed diffraction bright band appearing in the diffraction pattern of the diffraction light in the first area to be measured. The diffraction intensity curve presents a periodic change. For details, see Figure 2 . Figure 2 The horizontal axis of the diffraction intensity curve shown represents the diffraction angle, and the vertical axis represents the diffraction intensity. Figure 2 As shown, as the diffraction angle increases, the diffraction intensity will have a series of maximum and minimum values, and these maximum and minimum values ​​will repeat in a certain period.

[0079] In the case where it is determined that there is a periodic manufacturing error in the first area to be tested, the period of the manufacturing error of the grating can be calculated based on the diffraction intensity curve of the specific wavelength, thereby achieving a quantitative analysis of the manufacturing error of the grating. In some embodiments, the method further includes: obtaining the diffraction angle corresponding to two adjacent levels of diffraction light of a specific wavelength from the periodically distributed diffraction bright band; determining the manufacturing error period of the first area to be tested based on the wavelength value of the specific wavelength and the diffraction angle corresponding to two adjacent levels of diffraction light. Specifically, the period D of the manufacturing error of the grating is calculated based on the following calculation formula:

[0080]

[0081] Among them, λ is the wavelength value of a specific wavelength, θ m+1 ,θ m is the diffraction angle corresponding to two adjacent diffraction levels. Figure 2The diffraction intensity curve shown can also be obtained from the diffraction angles corresponding to any other two adjacent diffraction lights.

[0082] Based on the above steps S110 to S140, after the first test area of ​​the grating to be tested is checked for manufacturing defects, the light source device and the detection device remain stationary, and only the first motion mechanism is controlled to move, driving the carrier on which the optical waveguide is placed to move along the second direction and / or the third direction, so as to detect other test areas of the grating to be tested. In some embodiments, the method further includes: controlling the first motion mechanism to move, driving the carrier on which the optical waveguide is placed to move along the second direction and / or the third direction, so that the incident light emitted by the light source device is directed to the second test area of ​​the grating to be tested, wherein the first direction, the second direction and the third direction are perpendicular to each other; controlling the detection device to scan the second test area to obtain scanning data corresponding to the diffracted light of the second test area; obtaining the diffraction pattern of the diffracted light of the second test area according to the scanning data corresponding to the diffracted light of the second test area; when a specific diffraction bright band appears in the diffraction pattern of the diffracted light of the second test area, it is determined that the second test area has a manufacturing defect, and the distribution of the specific diffraction bright band is different from the distribution of the diffraction bright band in the diffraction pattern when the grating to be tested is defect-free.

[0083] Based on the above steps S110 to S140, multiple test regions of the coupling grating disposed on the optical waveguide are tested. If a manufacturing defect occurs in at least one test region, it is determined that the coupling grating has a manufacturing defect.

[0084] Based on the above steps S110 to S140, multiple test areas of the outcoupling grating arranged on the optical waveguide are tested. When a manufacturing defect occurs in at least one of the test areas, it is determined that the outcoupling grating has a manufacturing defect.

[0085] In some embodiments, when a coupling-in grating or a coupling-out grating disposed on the optical waveguide has a manufacturing defect, the method further includes: the light source device emits incident light, and when the incident light is incident on the coupling-in grating, the first motion mechanism is controlled to move, so as to drive the carrier on which the optical waveguide is placed to move and / or rotate, until the intensity of the diffracted light of the coupling-out grating received by the detection device reaches a preset requirement; the detection device is controlled to scan the coupling-out grating to obtain scanning data corresponding to the diffracted light of the coupling-out grating; and a diffraction pattern of the diffracted light of the coupling-out grating is obtained according to the scanning data corresponding to the diffracted light of the coupling-out grating. Sample, wherein a specific diffraction bright band appears in the diffraction pattern of the diffracted light of the out-coupling grating; a first diffraction intensity is obtained according to the specific diffraction bright band that appears in the diffraction pattern of the diffraction light of the out-coupling grating; a second diffraction intensity is obtained, wherein the second diffraction intensity is determined based on the diffraction bright band in the diffraction pattern when both the in-coupling grating and the out-coupling grating have no manufacturing defects; a value of the degree of influence of the imaging quality corresponding to the grating manufacturing error is determined according to the first diffraction intensity and the second diffraction intensity; and a result of the influence of the manufacturing defects of the in-coupling grating or the out-coupling grating arranged on the optical waveguide on the imaging quality is determined according to the value of the degree of influence of the imaging quality. The detection method provided in this embodiment is applicable to the case where a manufacturing defect occurs in the in-coupling grating arranged on the optical waveguide and the out-coupling grating does not have a manufacturing defect, or a manufacturing defect occurs in the out-coupling grating arranged on the optical waveguide and the in-coupling grating does not have a manufacturing defect.

[0086] In this embodiment, the movable direction of the support platform and the rotation direction of the support platform can refer to the above embodiments, and will not be described in detail here.

[0087] The intensity of the diffracted light received by the detection device from the out-coupled grating meets the preset requirement that the intensity of the diffracted light reaches the maximum during the movement and / or rotation of the supporting platform.

[0088] The imaging quality impact value α corresponding to the grating manufacturing error is determined based on the following calculation formula:

[0089]

[0090] Wherein, I0 is the first diffraction intensity, and I is the second diffraction intensity. When the imaging quality influence degree value exceeds the preset threshold value, it is determined that the influence result of the manufacturing defects of the coupling-in grating and / or the coupling-out grating arranged on the optical waveguide on the imaging quality is influenced. When the imaging quality influence degree value does not exceed the preset threshold value, it is determined that the influence result of the manufacturing defects of the coupling-in grating and / or the coupling-out grating arranged on the optical waveguide on the imaging quality is not influenced. In this way, the influence of the manufacturing defects of the coupling-in grating and / or the coupling-out grating on the optical waveguide on the imaging quality can be realized, so as to provide a more accurate basis for the subsequent processing of the optical waveguide.

[0091] An embodiment of the present invention provides a grating detection device, according to Figure 3As shown, the grating detection device includes a control device 310 , a light source device 320 , a detection device 330 , a carrier platform 340 and a first motion mechanism 350 .

[0092] The control device 310 is used to control the movement of the first motion mechanism 350 when the light source device 320 emits incident light to a first test area of ​​the test grating set on the optical waveguide, so as to drive the support platform 340 on which the optical waveguide is placed to move along the first direction and rotate around the first direction until the intensity of the diffracted light of the first test area received by the detection device 330 reaches a preset requirement, wherein the first direction is perpendicular to the plane on which the optical waveguide is placed on the support platform 340; control the detection device 330 to scan the first test area to obtain scanning data corresponding to the diffracted light of the first test area; obtain a diffraction pattern of the diffracted light of the first test area based on the scanning data corresponding to the diffracted light of the first test area; and determine that a manufacturing defect occurs in the first test area when a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first test area, and the distribution of the specific diffraction bright band is different from the diffraction bright band in the diffraction pattern when the test grating has no manufacturing defect.

[0093] In some embodiments, the device further comprises a second motion mechanism and a third motion mechanism. The control device is used to control the movement of the second motion mechanism to drive the light source device to emit incident light at different angles. The control device is used to control the movement of the third motion mechanism to drive the detection device to receive diffracted light at different angles.

[0094] In the case of detecting whether a coupling-in grating or a coupling-out grating arranged on an optical waveguide has manufacturing defects based on a grating detection device, the light source device and the detection device are located on the same side of the optical waveguide, see Figure 3 . Figure 3 The grating region 1 shown is a coupling-in grating, the grating region 2 is an coupling-out grating, and point-1 is a region to be measured.

[0095] In the case where the grating detection device is used to detect the effect of a coupling-in grating with manufacturing defects or a coupling-out grating with manufacturing defects on the imaging of an optical waveguide, and the optical waveguide is a reflective optical structure, the light source device and the detection device are located on the same side of the optical waveguide, see Figure 4 . Figure 4 The grating region 1 shown is the coupling-in grating, and the grating region 2 is the coupling-out grating. Figure 4 Point-1 representing the area to be measured is shown, but the incident light emitted by the light source device covers the entire grating area 1, and the diffraction light received by the detection device is obtained from scanning the entire grating area 2.

[0096] When the grating detection device is used to detect the influence of a coupling-in grating with manufacturing defects or an outcoupling grating with manufacturing defects on the imaging of an optical waveguide, and the optical waveguide is a transmissive optical structure, the light source device and the detection device are located on different sides of the optical waveguide.

[0097] When the optical waveguide is a reflective optical structure, the light incident on the coupling-in grating of the optical waveguide and the light coupled out from the coupling-out grating of the optical waveguide are located on the same side of the optical waveguide. When the optical waveguide is a transmissive optical structure, the light incident on the coupling-in grating of the optical waveguide and the light coupled out from the coupling-out grating of the optical waveguide are located on different sides of the optical waveguide.

[0098] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the device embodiment, its related parts can be referred to the partial description of the method embodiment.

[0099] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0100] The embodiments of the present specification may be systems, methods and / or computer program products. The computer program product may include a computer-readable storage medium carrying computer instructions for causing a processor to implement various aspects of the embodiments of the present specification.

[0101] A computer-readable storage medium may be a tangible device that can hold and store computer instructions used by a computer instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which computer instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0102] The computer instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device through a network layer, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network layer may include copper transmission cables, optical fiber transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. The network layer adapter card or network layer interface in each computing / processing device receives the computer instructions from the network layer and forwards the computer instructions for storage in a computer-readable storage medium in each computing / processing device.

[0103] The flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the systems, methods and computer program products according to the multiple embodiments of this specification. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a computer instruction, and a part of a module, a program segment or a computer instruction contains one or more executable computer instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or the flowchart, and the combination of the boxes in the block diagram and / or the flowchart can be implemented by a dedicated hardware-based system that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. It is well known to those skilled in the art that it is equivalent to implement it by hardware, implement it by software, and implement it by combining software and hardware.

[0104] The embodiments of the present specification have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A grating detection method, characterized in that: include: When the light source device emits incident light to a first area to be measured of a grating to be measured set on the optical waveguide, the first motion mechanism is controlled to move, so as to drive a carrier on which the optical waveguide is placed to move along a first direction and rotate around the first direction until the intensity of the diffracted light of the first area to be measured received by the detection device reaches a preset requirement, wherein the first direction is perpendicular to the plane on which the optical waveguide is placed on the carrier; Controlling the detection device to scan the first area to be measured to obtain scanning data corresponding to the diffracted light of the first area to be measured; Obtaining a diffraction pattern of the diffracted light of the first area to be measured according to scanning data corresponding to the diffracted light of the first area to be measured; When a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first area to be measured, it is determined that a manufacturing defect occurs in the first area to be measured, and the distribution of the specific diffraction bright band is different from the distribution of the diffraction bright band in the diffraction pattern when the grating to be measured has no manufacturing defect.

2. The method according to claim 1, characterized in that The method further comprises: In a case where the specific diffraction bright band is a periodically distributed diffraction bright band, determining that a periodic manufacturing error exists in the first to-be-tested area; In a case where the specific diffraction bright band is a randomly distributed diffraction bright band, it is determined that a non-periodic manufacturing error exists in the first to-be-tested area.

3. The method according to claim 2, characterized in that In the case where the specific diffraction bright band is a periodically distributed diffraction bright band, the method further includes: Obtaining diffraction angles corresponding to two adjacent levels of diffraction light of a specific wavelength from the periodically distributed diffraction bright bands; The manufacturing error period of the first area to be measured is determined according to the wavelength value of the specific wavelength and the diffraction angles corresponding to two adjacent orders of diffraction light.

4. The method according to claim 1, characterized in that: The grating to be tested is an in-coupled grating or an out-coupled grating. In the case where a manufacturing defect occurs in the in-coupled grating or the out-coupled grating, the method further comprises: The light source device emits incident light, and when the incident light is incident on the coupling-in grating, the first motion mechanism is controlled to move, so as to drive the carrier platform on which the optical waveguide is placed to move and / or rotate, until the intensity of the diffracted light of the coupling-out grating received by the detection device reaches a preset requirement; Controlling the detection device to scan the out-coupling grating to obtain scanning data corresponding to the diffracted light of the out-coupling grating; Obtaining a diffraction pattern of the diffracted light of the out-coupling grating according to the scanning data corresponding to the diffracted light of the out-coupling grating, wherein the diffraction pattern of the diffracted light of the out-coupling grating has a specific diffraction bright band; Obtaining a first diffraction intensity according to a specific diffraction bright band appearing in the diffraction pattern of the diffracted light of the outcoupling grating; Obtaining a second diffraction intensity, wherein the second diffraction intensity is determined based on a diffraction bright band in a diffraction pattern when both the coupling-in grating and the coupling-out grating have no manufacturing defects; Determining an imaging quality influence degree value corresponding to a grating manufacturing error according to the first diffraction intensity and the second diffraction intensity; According to the imaging quality influence degree value, the influence result of the manufacturing defect of the coupling-in grating or the coupling-out grating arranged on the optical waveguide on the imaging quality is determined.

5. The method according to claim 1, characterized in that: After completing the detection of the first to-be-tested area of ​​the to-be-tested grating, the method further includes: Controlling the movement of the first motion mechanism to drive the carrier on which the optical waveguide is placed to move along the second direction and / or the third direction, so that the incident light emitted by the light source device is directed toward the second area to be measured of the grating to be measured, wherein the first direction, the second direction and the third direction are perpendicular to each other; Controlling the detection device to scan the second area to be measured to obtain scanning data corresponding to the diffracted light of the second area to be measured; Obtaining a diffraction pattern of the diffracted light of the second area to be measured according to the scanning data corresponding to the diffracted light of the second area to be measured; When a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the second test area, it is determined that a manufacturing defect occurs in the second test area, and the distribution of the specific diffraction bright band is different from the diffraction bright band in the diffraction pattern when the test grating is defect-free.

6. The method according to any one of claims 1 to 5, characterized in that: The controlling detection device is aligned with the first area to be measured to scan, and the scanning data corresponding to the diffracted light of the first area to be measured is obtained, including: The control detection device is aligned with the first area to be measured and scans within a set scanning plane to obtain scanning data corresponding to the diffracted light of the first area to be measured, wherein the set scanning plane is a plane determined based on the incident direction of the incident light and the first direction.

7. The method according to any one of claims 1 to 5, characterized in that: The controlling the first motion mechanism to move, driving the carrier platform on which the optical waveguide is placed to move along a first direction and rotate around the first direction, until the intensity of the diffracted light of the first area to be measured received by the detection device reaches a preset requirement, comprises: Controlling the first motion mechanism to move, driving the carrier on which the optical waveguide is placed to move along a first direction, until the intensity of the diffracted light from the first area to be measured received by the detection device reaches a first preset requirement; The first motion mechanism is controlled to move, so as to drive the support platform on which the optical waveguide is placed to rotate along a first direction until the intensity of the diffracted light from the first area to be measured received by the detection device reaches a second preset requirement.

8. A grating detection device, characterized in that: include: A control device, a light source device, a detection device, a carrier platform and a first motion mechanism; wherein, The control device is used for controlling the first motion mechanism to move when the light source device emits incident light to a first to-be-measured area of ​​the to-be-measured grating disposed on the optical waveguide, so as to drive the carrier on which the optical waveguide is placed to move along a first direction and rotate around the first direction until the intensity of the diffracted light of the first to-be-measured area received by the detection device reaches a preset requirement, wherein the first direction is perpendicular to the plane on which the optical waveguide is placed on the carrier; Controlling the detection device to scan the first area to be measured to obtain scanning data corresponding to the diffracted light of the first area to be measured; Obtaining a diffraction pattern of the diffracted light of the first area to be measured according to scanning data corresponding to the diffracted light of the first area to be measured; When a specific diffraction bright band appears in the diffraction pattern of the diffraction light of the first area to be measured, it is determined that a manufacturing defect occurs in the first area to be measured, and the distribution of the specific diffraction bright band is different from the distribution of the diffraction bright band in the diffraction pattern when the grating to be measured has no manufacturing defect.

9. The device according to claim 8, characterized in that The device also includes a second motion mechanism and a third motion mechanism; wherein, The control device is used to control the movement of the second motion mechanism to drive the light source device to emit incident light at different angles; The control device is used to control the movement of the third motion mechanism to drive the detection device to receive diffracted light at different angles.

10. The device according to claim 8, characterized in that In the case where the grating detection device detects whether a coupling-in grating or a coupling-out grating arranged on the optical waveguide has a manufacturing defect, the light source device and the detection device are located on the same side of the optical waveguide; When the grating detection device is used to detect the influence of a coupling-in grating with manufacturing defects or an out-coupling grating with manufacturing defects on the imaging of the optical waveguide, and the optical waveguide is a reflective optical structure, the light source device and the detection device are located on the same side of the optical waveguide; when the grating detection device is used to detect the influence of a coupling-in grating with manufacturing defects or an out-coupling grating with manufacturing defects on the imaging of the optical waveguide, and the optical waveguide is a transmissive optical structure, the light source device and the detection device are located on different sides of the optical waveguide.

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