CN217542339U - Period measuring device for transmission type grating - Google Patents
Period measuring device for transmission type grating Download PDFInfo
- Publication number
- CN217542339U CN217542339U CN202220912003.2U CN202220912003U CN217542339U CN 217542339 U CN217542339 U CN 217542339U CN 202220912003 U CN202220912003 U CN 202220912003U CN 217542339 U CN217542339 U CN 217542339U
- Authority
- CN
- China
- Prior art keywords
- grating
- guide rail
- base
- grating period
- period measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Testing Of Optical Devices Or Fibers (AREA)
Abstract
The present application provides a period measuring apparatus of a transmission type grating, which may include: the base comprises a bearing surface, and the grating to be detected is arranged on the base; the light source is arranged on the base, and the light emitting direction of the light source is parallel to the bearing surface of the base; the arc-shaped guide rail is arranged on the base; and the photoelectric detector is arranged on the arc-shaped guide rail and movably connected with the arc-shaped guide rail. The diffraction light of the specific diffraction order of the grating is detected by the photoelectric detector, the diffraction angle of the diffraction light is recorded, and the grating period of the transmission grating is quickly measured based on the grating diffraction equation, so that a simple, convenient and effective tool is provided for measuring and verifying the grating period of the waveguide design grating. The device is simple to operate, and the grating period is measured quickly, simply and conveniently. Meanwhile, parameters of the device can be adjusted according to actual conditions, and the grating period measuring range is wide.
Description
Technical Field
The application relates to the technical field of grating period measurement, in particular to a period measuring device of a transmission type grating.
Background
The diffraction light waveguide of the Augmented Reality (AR) glasses usually adopts a grating to realize light coupling-in and coupling-out, and the grating period is an important structural parameter of the grating, which has an important influence on the diffraction characteristics of the grating (such as the direction of the diffraction order and the diffraction efficiency thereof), thereby affecting the overall coupling-in and coupling-out efficiency of the waveguide. In optimizing waveguide performance, the grating period of the grating in or out of the waveguide in the coupling region is generally set to optimize waveguide display performance. However, there are errors in the actual grating processing process, which may cause some defects in the grating in the coupling-in or coupling-out region, i.e. the actual grating period value does not necessarily conform to the theoretical value, thereby causing the problems of reduced coupling-out efficiency, poor uniformity, etc., and thus requiring measurement and verification.
At present, the grating period of the grating to be measured can be directly observed through a scanning electron microscope, the grating period value is measured, but the scanning electron microscope is expensive, and the production cost of the grating is increased.
SUMMERY OF THE UTILITY MODEL
The present embodiment proposes a transmission grating period measurement device to solve at least one of the above-mentioned problems.
The embodiments of the present application achieve the above object by the following means.
A transmission type grating period measuring apparatus comprising: the base comprises a bearing surface, and the grating to be detected is arranged on the base; the light source is arranged on the base, and the light emitting direction of the light source is parallel to the bearing surface of the base; the arc-shaped guide rail is arranged on the base; and the photoelectric detector is arranged on the circular arc guide rail and movably connected with the circular arc guide rail.
In one embodiment, the method further comprises: the rotating platform is arranged on the base and is rotationally connected with the base, and the grating to be detected is arranged on the rotating platform.
In one embodiment, the method further comprises: the fixture is arranged on the rotating platform and fixedly connected with the rotating platform, and the fixture is used for fixing the grating to be detected.
In one embodiment, the circular arc guide rail comprises: the extending direction of spout is unanimous with the extending direction of convex guide rail, photoelectric detector includes: the sliding block is positioned at the bottom of the photoelectric detector and is in sliding connection with the sliding groove.
In one embodiment, the period measuring device of the transmission type grating further includes: the lifting rod is arranged on the base, and the light source is arranged on the lifting rod.
In one embodiment, the circular arc guide rail is provided with a first scale, and the first scale is arranged along the extension direction of the circumference of the circular arc guide rail.
In one embodiment, the circular arc-shaped guide rail is detachably connected with the base; the bottom end of the circular arc-shaped guide rail is provided with external threads, the bearing surface of the base is provided with a threaded hole, and the external threads of the circular arc-shaped guide rail are in threaded fit with the threaded hole of the base.
In one embodiment, a second scale is arranged on the circumference of the rotating table, and the second scale is arranged along the extending direction of the circumference of the rotating table.
In one embodiment, the light source is a laser.
In one embodiment, the photodetector is a CCD sensor or a CMOS sensor.
According to the scheme provided by the embodiment of the application, the photoelectric detector is used for detecting the diffraction light of the specific diffraction order of the grating, the diffraction angle of the diffraction light is recorded, and the grating period of the transmission grating is rapidly measured based on the grating diffraction equation, so that a simple, convenient and effective tool is provided for the grating period measurement verification of the waveguide design grating. The device is simple to operate, the grating period is measured quickly, conveniently and simply, the parameters of the device can be adjusted according to actual conditions, and the grating period measuring range is wide.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a transmission grating period measuring device according to an embodiment of the present disclosure.
Fig. 2 is a schematic diagram of a measurement apparatus for measuring the grating period of a transmission diffraction grating.
FIG. 3 is a diagram illustrating the diffraction angle correction for transmission of-1 order light.
Description of the drawings: the period measuring device comprises a transmission type grating period measuring device 10, a base 100, a bearing surface 110, a rotating platform 200, a grating 300 to be measured, a light source 400, a circular arc guide rail 500, a sliding groove 530, a photoelectric detector 600, a sliding block 610, a clamp 700 and a lifting rod 800.
Detailed Description
Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present application and are not to be construed as limiting the present application.
In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The diffraction light waveguide of the AR glasses usually adopts a grating to realize light coupling-in and coupling-out, and the grating period as an important structural parameter of the grating has an important influence on the diffraction characteristics of the grating (such as the direction of the diffraction order and the diffraction efficiency thereof), thereby affecting the overall coupling-in and coupling-out efficiency of the waveguide. In optimizing waveguide performance, the grating period of the grating in or out of the waveguide coupling region is generally set to optimize waveguide display performance. However, there are errors in the actual grating processing process, which may cause some defects in the grating in the coupling-in or coupling-out region, i.e. the actual grating period value does not necessarily conform to the theoretical value, thereby causing the problems of reduced coupling-out efficiency, poor uniformity, etc., and thus requiring measurement and verification.
The diffraction light waveguide of the AR glasses usually adopts a grating to realize light coupling-in and coupling-out, and the grating period d as an important structural parameter of the grating has an important influence on the diffraction characteristics of the grating (such as the direction of the diffraction order and the diffraction efficiency thereof), thereby affecting the overall coupling-in and coupling-out efficiency of the waveguide. When designing waveguide grating parameters, the grating period of the grating in or out of the coupling region is generally designed to optimize the waveguide display performance, but in the actual manufacturing process of the diffraction grating, due to the influence of various factors, the grooves of the grating have various errors, such as non-parallelism of the grating grooves, spacing error of the grating grooves, inconsistency of the groove shapes and the like, which cause deviation between the actual grating period value and the theoretical design value, and cause influence on the spectral quality of the grating, such as stray light, reduction of reflection-1 order diffraction efficiency and the like, which can adversely affect the waveguide display performance. At present, the grating period deviation caused by the grating grooving error can be measured by directly observing the grating structure through a scanning electron microscope, and the value of the grating period is measured, but the scanning electron microscope is expensive and can damage a sample.
The application provides a periodic measurement device of transmission type grating, aims at providing a simple and convenient quick measuring tool for grating periodic measurement verification of waveguide design grating, helps waveguide wholeness to carry out optimization to promote the display performance of AR glasses.
Referring to fig. 1, the present application provides a transmission grating period measuring apparatus 10, which may include: the light source device comprises a base 100, a rotating platform 200, a light source 400, a circular arc guide rail 500 and a photoelectric detector 600.
The base 100 may be a square base 100 or a circular base 100, and the thickness of the base 100 may be smaller than the length, width or diameter of the base 100 to ensure the stability of the base 100. The base 100 includes a supporting surface 110, the supporting surface 110 is a smooth and flat surface, and the base 100 is used for supporting other components such as the rotating table 200, the light source 400, the circular arc guide 500, and the photodetector 600. It is to be understood that the chassis 100 shown in FIG. 1 is for illustration only, and the present application is not limited to a particular shape of the chassis 100.
The rotating platform 200 is disposed on the bearing surface 110 of the base 100, the rotating platform 200 is rotatably connected to the base 100, and the rotating platform 200 is used for bearing the grating 300 to be tested; the rotation stage 200 may be a cylindrical structure to facilitate a user's rotation operation. The bottom of the rotating platform 200 may be provided with a rotating slot, the supporting surface 110 of the base 100 may be provided with a rotating rod, the rotating platform 200 may be rotatably connected to the rotating rod on the supporting surface 110 through the rotating slot, so as to realize the rotational connection between the rotating platform 200 and the base 100, and the rotating platform 200 may be used to adjust the incident angle of the incident light. It should be understood that the rotary table 200 shown in fig. 1 is only an illustration, and the present application is not limited to the specific shape of the rotary table 200.
The light source 400 is disposed on the base 100, the light source 400 is disposed on one side of the rotating platform 200, and the light emitting direction of the light source 400 points to the rotating platform 200, so as to ensure that the emergent light of the light source 400 can pass through the grating 300 to be measured on the rotating platform 200. In addition, the light emitting direction of the light source 400 is parallel to the carrying surface 110 of the base 100. The light source 400 is used to emit a light beam, typically a single wavelength laser or LED light source 400. It is to be understood that the light source 400 shown in fig. 1 is merely exemplary, and the present application is not limited to the specific form of the light source 400.
The circular arc guide rail 500 is disposed on the base 100, and the circular arc guide rail 500 is located on a side of the rotating platform 200 away from the light source 400; the circular arc guide rail 500 is used to enable the position of the object disposed on the circular arc guide rail 500 to be changed along the plane of the circular arc guide rail 500. Meanwhile, in the present embodiment, the rotary table 200 is disposed at the center of the circular arc guide rail 500, so that the distance from the rotary table 200 is maintained regardless of the position of the photodetector 600 on the circular arc guide rail 500. The above-described arrangement of the circular arc guide rail 500 functions to control the variable.
The photoelectric detector 600 is arranged on the arc-shaped guide rail 500 and movably connected with the arc-shaped guide rail 500; that is, the photodetector 600 can realize a position change on the circular arc shaped guide rail 500 along the path of the circular arc shaped guide rail 500. The photodetector 600 is used to collect the optical signal image in real time and perform data processing.
The circle center of the circular arc guide rail 500 is located on a connecting line between the measuring point of the grating 300 to be measured and the light source 400, and the circular arc guide rail 500 may be axisymmetric along the connecting line. The arrangement of the arc-shaped guide rail 500 enables the area detectable by the photoelectric detector 600 to be more symmetrical, which is helpful for improving the detection accuracy of the photoelectric detector 600.
The working principle of the embodiment of the application is as follows: the light source 400 is turned on, so that the incident light of the light source 400 passes through the grating 300 to be measured disposed on the rotating table 200, the position of the photodetector 600 on the circular arc guide rail 500 is adjusted, and the photodetector 600 collects and records the optical signal image.
As shown in FIG. 2, a light source 400 emits a path of light with a wavelength λ incident on the surface of the grating 300 to be measured rotated by a certain angle i, and the transmission-1 (T) is taken by measuring the diffraction direction of the transmission order of the grating 300 to be measured -1 ) The order angle α (α is the angle of the transmitted light with respect to the incident light, and point O in the figure is the 0 ° position on the scale on the circular arc guide 500) according to the diffraction grating equation
The corresponding relation between the grating period d and the angle alpha of the grating 300 to be measured can be derived, where T is specified -1 The order ray is taken to the right and left of the incident ray. Therefore, the value of the corresponding grating period d can be calculated at different alpha positions according to the corresponding relation between d and the angle alpha, and the light can be rapidly measuredThe purpose of the gate period.
In conclusion, the device in the embodiment of the application detects the diffraction light of the specific diffraction order of the grating through the photoelectric detector, records the diffraction angle of the diffraction light, and rapidly measures the grating period of the transmission grating based on the grating diffraction equation, thereby providing a simple, convenient and effective tool for the grating period measurement and verification of the waveguide design grating. The device is simple to operate, and the grating period is measured quickly, simply and conveniently. Meanwhile, parameters of the device can be adjusted according to actual conditions, and the grating period measuring range is wide.
In an embodiment, referring to fig. 1 again, the transmission type grating period measuring apparatus 10 may further include a fixture 700, where the fixture 700 is disposed on the rotating platform 200 and is fixedly connected to the rotating platform 200, such as welded, screwed, etc., so as to ensure that the fixture 700 does not loosen after clamping the grating 300 to be measured. The fixture 700 is used for fixing the grating 300 to be tested. In this embodiment, the clamp 700 may be a spring clamp. In the present embodiment, the clamp 700 is used for clamping the grating 300 to be measured, and should clamp the grating 300 to be measured during fixing, but the grating 300 to be measured is not damaged, and a flexible cushion layer such as rubber, resin and the like is provided on the clamping surface of the clamp 700. Meanwhile, the clamp 700 is fixed to the rotary table 200 and can freely rotate along with the rotary table 200. For example, the clamp 700 may be rotatably coupled to the rotary table 200 by providing a rotary shaft hole in a bottom surface of the clamp 700 and coupling the rotary shaft hole to a rotary shaft provided on the rotary table 200. When the jig 700 fixes the grating 300 to be measured, it is necessary to ensure that the measurement position of the grating 300 to be measured is on the rotation axis of the rotation stage 200, and the measurement position is not changed by the rotation of the rotation stage 200. The arrangement of the clamp 700 can ensure the accuracy of the position of the grating 300 to be tested, thereby improving the testing precision.
In one embodiment, the circular arc guide rail 500 may include: a sliding groove 530, an extending direction of the sliding groove 530 is identical to an extending direction of the circular arc guide rail 500, and the photodetector 600 includes: the sliding block 610 is located at the bottom of the photodetector 600, and the sliding block 610 is slidably connected with the sliding groove 530. The arrangement of the photodetector 600 and the circular arc-shaped guide rail 500 helps to improve the fault tolerance rate of the device in use.
In one embodiment, the transmission grating period measurement device 10 further comprises: the lifting rod 800, the lifting rod 800 is arranged on the base 100, and the light source 400 is arranged on the lifting rod 800. It can be understood that the lifting rod 800 not only can perform a lifting function to change the height of the light source 400, but also can rotate relative to the base 100 to change the light emitting direction of the light source 400.
In an embodiment, the circular arc guide rail 500 is provided with first scales, the first scales are arranged along the extending direction of the circumference of the circular arc guide rail 500, the intersection point of the connecting line of the measuring point of the grating 300 to be measured and the light source 400 and the circular arc guide rail 500 is 0 °, and the angle on one side of the intersection point is plus and the angle on the other side is minus. The setting of above-mentioned scale can the change of convenient to use person record angle, uses the nodical 0 of crossing of line and circular arc guide rail 500 simultaneously for the scale symmetric distribution on nodical both sides can be more convenient the numerical value of the nodical both sides of calculation.
In one embodiment, the circular arc guide rail 500 is detachably connected to the base 100. For example, the period measuring device 10 of the transmission grating can be conveniently detached and installed by being detachably connected, such as a snap-fit connection or a mortise connection, in this embodiment, the bottom end of the circular arc guide rail 500 is provided with an external thread, the bearing surface of the base 100 is provided with a threaded hole, and the external thread of the circular arc guide rail 500 is in threaded fit with the threaded hole of the base 100.
In an embodiment, the circumference of the rotating platform 200 is provided with a second scale, the second scale is arranged along the extending direction of the circumference of the rotating platform 200, the second scale is opposite to the photoelectric detector 600, the second scale is arranged to facilitate obtaining the rotation amount of the rotating platform 200, and further facilitate measuring the grating period of the grating 300 to be measured.
In one embodiment, the clamp 700 is made of a flexible material, such as rubber, resin, or the like. The fixture 700 made of the flexible material can reduce the probability that the fixture 700 damages the grating 300 to be detected, and further improve the detection precision and efficiency.
In one embodiment, the photodetector 600 is a CCD sensor or a CMOS sensor. The incident light is detected to penetrate through the grating 300 to be detected to diffract the optical signal of the diffraction order with the higher diffraction order except the 0 order, the detected optical signal is diffracted by the 1 order with the higher diffraction order, and the detected optical signal can be converted into the electric signal at the same time, so that the optical sensitivity to the diffracted light with the wavelength of lambda is better. A CCD or CMOS image sensor is typically used, where a CCD camera is used, which can be connected to a computer host to collect light signal images in real time for data processing.
Referring to fig. 1 and fig. 3, the working flow of the apparatus is as follows:
1. installing the grating 300 to be tested on the rotary table 200, and turning on the light source 400 to ensure that emergent light of the light source 400 is vertically incident on the grating;
2. rotating the rotation stage 200 by a certain angle i (i =0 ° without rotation) to ensure that the light can generate other diffraction orders except the diffraction order 0, such as transmission order 1 and transmission order-1, when passing through the grating;
the CCD camera starts scanning from an angle of-90 degrees to an angle of 90 degrees (or starts scanning from an angle of 90 degrees to an angle of-90 degrees) on the circular arc guide rail 500, when light of other diffraction orders except for transmission 0 order is normally incident to a receiving port of the photoelectric detector 600 (the photoelectric detector 600 used herein is a CCD camera), the camera acquisition software displays a light spot, the light spot is acquired, the transmission-1 order light signal is acquired, and the center of the camera is positioned along transmission-1 (T) of the transmission light ray at the moment -1 ) The step angle α points to the scale position α on the circular arc guide 500 1 (not shown in the figures);
4. meanwhile, software analyzes the CCD collected image, and if the horizontal distance L of the image spot center deviating from the camera center pixel is calculated, the diffraction angle alpha = alpha of the actual diffraction light 1 +/-arctan L/R, wherein the sign is selected according to whether the center of the light spot deviates from the center pixel of the camera to the left or right, as shown in FIG. 3, the center of the image light spot deviates from the center pixel of the camera to the right, and the diffraction angle of the transmitted-1 order light is corrected to be alpha = alpha 1 -arctan L/R；
5. Finally, the wavelength λ, the incident angle i and the diffraction angle α of the light source 400 are substituted into the formula:
and calculating to obtain the value of the grating period d of the grating 300 to be measured.
In the formula:
d is the grating period of the grating to be measured;
i is an incident angle;
alpha is a diffraction angle;
λ is the light wavelength emitted by the light source.
The application provides a transmission type grating period measuring device. The device detects diffraction light of a specific diffraction order of the grating through the photoelectric detector, records the diffraction angle of the diffraction light, and rapidly measures the grating period of the transmission grating based on the grating diffraction equation, thereby providing a simple, convenient and effective tool for measuring and verifying the grating period of the waveguide design grating. The device is simple to operate, and the grating period is measured quickly, simply and conveniently. Meanwhile, parameters of the device can be adjusted according to actual conditions, and the grating period measuring range is wide.
The description of the terms "some embodiments," "other embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiments or examples is included in at least one embodiment or example of the application. In this application, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the various embodiments or examples and features of the various embodiments or examples described in this application can be combined and combined by those skilled in the art without conflicting.
The above embodiments are only for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.
Claims (10)
1. A period measuring apparatus of a transmission type grating, comprising:
a base including a bearing surface;
the light source is arranged on the base, and the light emitting direction of the light source is parallel to the bearing surface of the base;
the arc-shaped guide rail is arranged on the base; and
and the photoelectric detector is arranged on the arc-shaped guide rail and movably connected with the arc-shaped guide rail.
2. The transmission type grating period measuring device according to claim 1, further comprising:
the rotating platform is arranged on the base and is rotationally connected with the base.
3. The transmission type grating period measuring device according to claim 2, further comprising:
the fixture is arranged on the rotating platform and fixedly connected with the rotating platform, and the fixture is used for fixing the grating to be detected.
4. The transmission type grating period measuring device according to claim 3, wherein the circular arc guide rail comprises: the extending direction of the sliding groove is consistent with that of the arc-shaped guide rail, and a sliding block is arranged at the bottom of the photoelectric detector and is in sliding connection with the sliding groove.
5. The transmission type grating period measuring device according to claim 1, further comprising: the lifting rod is arranged on the base, and the light source is arranged on the lifting rod.
6. The transmission-type grating period measuring device according to claim 1, wherein the circular arc guide rail is provided with first scales, and the first scales are arranged along an extending direction of the circular arc guide rail.
7. The transmission-type grating period measuring device of claim 1, wherein the bottom end of the circular arc-shaped guide rail is provided with an external thread, the bearing surface of the base is provided with a threaded hole, and the external thread of the circular arc-shaped guide rail is in threaded fit with the threaded hole of the base.
8. A transmission type grating period measuring apparatus according to claim 2, wherein the rotation table is provided with second marks on a circumference thereof, the second marks being arranged along an extending direction of the circumference of the rotation table.
9. The transmission grating period measuring device of claim 1, wherein the light source is a laser.
10. The transmission grating period measuring device according to claim 1, wherein the photodetector is a CCD sensor or a CMOS sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220912003.2U CN217542339U (en) | 2022-04-19 | 2022-04-19 | Period measuring device for transmission type grating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220912003.2U CN217542339U (en) | 2022-04-19 | 2022-04-19 | Period measuring device for transmission type grating |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217542339U true CN217542339U (en) | 2022-10-04 |
Family
ID=83432368
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220912003.2U Active CN217542339U (en) | 2022-04-19 | 2022-04-19 | Period measuring device for transmission type grating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217542339U (en) |
-
2022
- 2022-04-19 CN CN202220912003.2U patent/CN217542339U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10145785B2 (en) | Optical element rotation type Mueller-matrix ellipsometer and method for measuring Mueller-matrix of sample using the same | |
| US8635783B2 (en) | Surface measurement instrument and method | |
| CN108332708B (en) | Automatic detection system and detection method for laser level meter | |
| US4882497A (en) | Method and apparatus of measuring outer diameter and structure of optical fiber | |
| US6462811B1 (en) | Automatic circular saw tooth inspection system and method | |
| US7511816B2 (en) | Methods and systems for determining drift in a position of a light beam with respect to a chuck | |
| CN102519389B (en) | Rotation positioning clamp and rotation positioning method for optical element | |
| US5416574A (en) | Automated optical measurement apparatus | |
| TWI472712B (en) | Vertical and parallelism detection system and its detection method | |
| CN217542339U (en) | Period measuring device for transmission type grating | |
| US5280336A (en) | Automated radius measurement apparatus | |
| TWI591325B (en) | Wafer inspection system and structure and method for monitoring incident beam position in a wafer inspection system | |
| CN210464396U (en) | Large lens eccentricity measuring device, centering component and clamping component | |
| CN104330360A (en) | Improved automatic glass stress detecting device | |
| CN110530614A (en) | The optical de-tection means and detection method of cylindrical mirror centre deviation | |
| CN116336995A (en) | Small-angle inspection device and small-angle inspection method based on auto-collimation principle | |
| CN217505161U (en) | Numerical aperture testing device for self-focusing lens | |
| CN213544383U (en) | Refractive index measuring device | |
| CN110082076B (en) | Device for detecting off-axis angle of light beam emitted by optical fiber lens and detection method thereof | |
| CN212658211U (en) | Optical quartz piece warpage check out test set | |
| CN209764385U (en) | Device for detecting off-axis angle of light beam emitted by fiber lens | |
| US6317209B1 (en) | Automated system for measurement of an optical property | |
| CN217542340U (en) | Period measuring device of two-dimensional grating | |
| CN111982006A (en) | System and method for measuring axial deformation of tunnel | |
| KR20230085956A (en) | Measurement of the surface profile of highly distorted samples |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |