CN220524907U - Optical measuring system - Google Patents

Abstract

The utility model provides an optical measurement system, which is suitable for measuring light beams emitted by a light-emitting unit, and comprises: the light receiving unit is used for receiving the light beam, the light receiving unit comprises a light receiving surface, the light receiving surface is not perpendicular to the optical axis of the light beam, and the light emitting unit moves relative to the light receiving unit. According to the embodiment of the application, the light emitting unit moves relative to the light receiving unit, and the light receiving unit acquires the image of the light beam, so that coordinate value data of the light beam can be obtained.

Description

Optical measuring system

Technical Field

Embodiments of the present utility model relate to optical measurement, and more particularly, to an optical measurement system.

Background

Fig. 1 shows that the beam profile meter 1 is used to measure the beam 12, the gaussian laser sensor needs to measure the beam characteristics by the beam profile meter (beam profiler) 1 before shipment, and since each beam profile meter 1 measures the light spot of only one beam (for example, a laser beam) 12 emitted by the light emitting unit 10, the light receiving range is difficult to cover multiple beams 12 at one time, and the optical axes of part of the beams 12 or all the beams 12 cannot be kept orthogonal to the measuring surface of the beam profile meter 1, so that the characteristics of the beams 12 cannot be measured, and the beam profile meter 1 is difficult to determine the light spot corresponding to each characteristic data. In addition, the beam profiler 1 cannot measure a plurality of spots at a time, and is expensive. If a plurality of beam profilers 1 are used to measure each beam 12, the equipment cost is high, the range of the actually measured beam 12 is about 5mm by 3mm, the plurality of beam profilers 1 are difficult to be installed together, and all the instruments cannot be confirmed to be on the same plane; the current beam profiler 1 is sized to interfere with each other, and the beam profiler 1 can be staggered up and down, but the laser energy is reduced due to the distance, resulting in a test error.

Current items tested on gaussian laser light sensors include electrical and optical tests measured using integrating sphere 2 shown in fig. 2, where electrical tests include testing its brightness, current (I), voltage (V), optical power and wavelength. For optical testing, there is no measuring instrument capable of testing a plurality of light beams 12 at one time, and there is no measuring instrument capable of testing non-orthogonal light beams 12, i.e. the situation that the optical axis of the light beam 12 is not orthogonal to the measuring instrument cannot be processed, and the inclination angle of the optical axis of the light beam 12 cannot be measured.

The light beam 12 is divided into a near field and a far field, the light spot of the near field shows nonlinear change, the light spot of the far field shows linear change, and the focal length of the light beam 12 is in the near field range, so that an image of the near field of the light beam 12 needs to be obtained, and the current measuring instrument cannot be erected 1-2 mm in front of the light emitting unit 10.

Disclosure of Invention

In view of the problems in the related art, an object of the present utility model is to provide an optical measurement system for measuring a light beam having an optical axis not perpendicular to a light receiving surface of a light receiving unit.

In order to achieve the above object, the present utility model provides an optical measurement system, which is suitable for measuring a light beam emitted by a light emitting unit, and includes: the light receiving unit is used for receiving the light beam, the light receiving unit comprises a light receiving surface, the light receiving surface is not perpendicular to the optical axis of the light beam, and the light emitting unit moves relative to the light receiving unit.

In some embodiments, the light emitting unit includes a lens, and the optical axis of the light beam is not perpendicular to the light receiving surface after the light beam is refracted by the lens.

In some embodiments, the light receiving unit is configured to receive the plurality of light beams emitted by the light emitting unit, and optical axes of the plurality of light beams are not parallel.

In some embodiments, the light receiving surface is not perpendicular to the optical axis of each light beam.

In some embodiments, the angle between the light-receiving surface and the optical axis of each light beam is the same.

In some embodiments, the light receiving surface receives a plurality of light beams on the same plane.

In some embodiments, the light receiving unit is stationary and the light emitting unit is moving.

In some embodiments, the optical metrology system further comprises: the six-axis platform is used for bearing the light-emitting unit and controlling the light-emitting unit to move.

In some embodiments, the optical metrology system further comprises: the other group of light receiving units is used for receiving the plurality of light beams emitted by the light emitting units in a one-to-one correspondence manner.

In some embodiments, the light emitting unit moves on a line between the light emitting unit and the light receiving unit.

In some embodiments, the connection line is perpendicular to the light receiving surface.

In some embodiments, the angle between the light receiving surface and the optical axis of the light beam is constant when the light emitting unit moves relative to the light receiving unit.

In some embodiments, the light emitting unit is moved at least 6 times relative to the light receiving unit.

In some embodiments, the light emitting unit translates relative to the light receiving unit.

In some embodiments, the optical metrology system further comprises: a six-axis platform, a processing unit in signal connection with the light receiving unit and generating an imaginary plane perpendicular to the optical axis of the light beam

In some embodiments, the processing unit is configured to calculate an angle between the imaginary plane and the light receiving surface.

In some embodiments, the processing unit is further configured to calculate an angle between the optical axis of the light beam and the light receiving surface.

In some embodiments, the processing unit is further configured to capture an image including the light beam, and divide the image into a plurality of sections.

In some embodiments, the light receiving unit is a CCD camera.

In some embodiments, the light beam emitted by the light emitting unit is a laser light beam.

The beneficial technical effects of the utility model are as follows:

according to the embodiment of the application, the light emitting unit moves relative to the light receiving unit, and the light receiving unit acquires the image of the light beam, so that coordinate value data of the light beam can be obtained.

Drawings

Fig. 1 shows measuring a beam using a light Shu Lunkuo instrument.

Fig. 2 shows an integrating sphere.

FIG. 3 illustrates an optical metrology system according to an embodiment of the present application.

Fig. 4 shows coordinate axes with the origin of the outward refraction of the light beam through the lens as the origin.

Fig. 5 shows the spot shape.

Fig. 6 shows an image of the light beam acquired by the light receiving unit before the light emitting unit moves.

Fig. 7 shows an image of the light beam acquired by the light receiving unit after the light emitting unit is moved.

Fig. 8 shows the superimposed images of fig. 6 and 7.

Fig. 9 shows that the light emitting unit includes a lens.

Fig. 10 shows a comparison table of spot images captured by a CCD camera and beam profiler.

Fig. 11 shows coordinate axes with the origin of the outward refraction of the light beam through the lens as the origin.

Fig. 12 shows the gaussian curve of the spot.

Fig. 13 shows the optical waist of the beam.

Fig. 14 is a schematic view showing a light beam of a laser light source extracted by using a CCD camera after being refracted by an aberration-free converging lens.

Fig. 15 shows another set of light receiving units.

Detailed Description

For a better understanding of the spirit of embodiments of the present application, reference is made to the following description of some preferred embodiments of the present application.

Embodiments of the present application will be described in detail below. Throughout the specification, identical or similar components and components having identical or similar functions are denoted by similar reference numerals. The embodiments described herein with respect to the drawings are of illustrative nature, of diagrammatic nature and are used to provide a basic understanding of the present application. The examples of the present application should not be construed as limiting the present application.

As used herein, the terms "substantially," "substantially," and "about" are used to describe and illustrate minor variations. When used in connection with an event or circumstance, the terms can refer to instances where the event or circumstance occurs precisely and instances where it occurs to the close approximation.

In this specification, unless specified or limited otherwise, relative terms such as: the terms "central," "longitudinal," "lateral," "front," "rear," "right," "left," "interior," "exterior," "lower," "upper," "horizontal," "vertical," "above," "below," "upper," "lower," "top," "bottom," and derivatives thereof (e.g., "horizontally," "downwardly," "upwardly," etc.) should be construed to refer to the directions as described in the discussion or as illustrated in the drawings. These relative terms are for convenience of description only and do not require that the present application be constructed or operated in a particular orientation.

For ease of description, "first," "second," "third," etc. may be used herein to distinguish between different components of a figure or series of figures. The terms "first," "second," "third," and the like are not intended to describe corresponding components.

Fig. 3 shows an optical measuring system according to an embodiment of the present application, adapted to measure a light beam 12 emitted by a light emitting unit 10, comprising: the light receiving unit 20 is configured to receive the light beam 12 and acquire an image of the light beam 12, the light receiving unit 20 includes a light receiving surface 22, the light receiving surface 22 is not perpendicular to the optical axis 12L of the light beam 12, and the light emitting unit 10 moves relative to the light receiving unit 20. Fig. 4 shows a coordinate axis with the origin of outward refraction of the light beam 12 through the lens 14 as the origin, and an axis perpendicular to the light receiving surface 22 as the z-axis, and in this coordinate axis, the light emitting unit 10 is actually moved along the z-axis, whereas in this coordinate axis, assuming that the light emitting unit 10 is not moved, the light receiving unit 20 is moved, the spot image (spot shape 110 as shown in fig. 5) of the light beam 12 before and after the movement, and the coordinates of the intersection point of the optical axis 12L with the light receiving surface 22 are acquired, and the angle α between the optical axis 12L and the z-axis can be obtained from the x, y, z-coordinate values before and after the movement, which can be obtained from the image acquired by the light emitting unit 10 with respect to the movement of the light receiving unit 20. In the embodiment of the present application, the light emitting unit 10 moves relative to the light receiving unit 20, and the light receiving unit 20 obtains the image of the light beam 12, so that the coordinate value data of the light beam 12 can be obtained. And an angle alpha between the optical axis 12L non-orthogonal to the light-receiving surface 22 and the normal (i.e., z-axis) to the light-receiving surface 22 can be obtained.

In some embodiments, the light emitting unit 10 moves on a line (i.e., z-axis) between the light emitting unit 10 and the light receiving unit 20, and the movement mode is simple. In some embodiments, the line is perpendicular to the light-receiving surface 22. In some embodiments, the angle between the light-receiving surface 22 and the optical axis 12L of the light beam 12 is constant when the light-emitting unit 10 moves relative to the light-receiving unit 20. In some embodiments, the light emitting unit 10 translates relative to the light receiving unit 20.

Referring to fig. 3, in some embodiments, the light-receiving surface 22 is non-perpendicular to the optical axis 12L of each light beam 12. In some embodiments, the light receiving surface 22 receives the plurality of light beams 12 in the same plane. In some embodiments, the light receiving unit 20 is fixed and the light emitting unit 10 is moved. In some embodiments, the optical metrology system further comprises: a six-axis platform 40 for carrying the light emitting unit 10 and controlling the movement of the light emitting unit 10.

Fig. 6 shows an image of the light beam 12 acquired by the light receiving unit 20 before the light emitting unit 10 moves relative to the light receiving unit 20, fig. 7 shows an image of the light beam 12 acquired by the light receiving unit 20 after the light emitting unit 10 moves relative to the light receiving unit 20, fig. 8 superimposes the two images together, and in fig. 8 the quadrants are divided (in actual measurement, the image is divided once every time, and then superimposed again), two light spots located in the same quadrant belong to the same light beam 12; or the quadrants are not divided, the spot closest to the leftmost spot belongs to the same beam 12, and the spot closest to the rightmost spot belongs to the same beam 12. The included angle between the lines is the included angle β between the light receiving surfaces 22 of the different light beams 12, and if there are more than two light beams 12 focused by the lens 14, the lines of the light spots of the light beams 12 intersect at a point. In the embodiment of the present application, by moving the light emitting unit 10 relative to the light receiving unit 20, and acquiring the images of the light beams 12 of the light emitting unit 10 by the light receiving unit 20, the included angles (azimuth angles) β of the light beams 12 on the light receiving surface 22, which have the optical axes 12L not perpendicular to the light receiving surface 22, can be obtained, and the light receiving unit 20 of the embodiment of the present application can obtain the images of the light beams 12 at one time, and can obtain the data of the light beams 12.

In some embodiments, the light emitting unit 10 is moved twice relative to the light receiving unit 20, and the light receiving unit 20 acquires an image of the far field of the light beam 12, and the light spot of the far field exhibits a linear change to obtain the above data. Embodiments of the present application only need to observe the change in the light beam 12 on the light receiving surface 22, which is a 2D plane, to obtain the above data of the light beam 12.

Referring to fig. 9, in some embodiments, the light emitting unit 10 includes a lens 14, and the optical axis 12L of the light beam 12 is not perpendicular to the light receiving surface 22 shown in fig. 3 after being refracted by the lens 14. In some embodiments, the light beam 12 emitted by the light emitting unit 10 is a laser light beam. In some embodiments, the light receiving unit 20 is configured to receive the plurality of light beams 12 emitted by the light emitting unit 10, and the optical axes 12L of the plurality of light beams 12 are not parallel.

Since the beam profiler 1 basically uses a CCD chip to acquire laser energy images, the embodiment of the present application uses an industrial camera instead of the beam profiler 1, i.e., the light receiving unit 20 is a CCD camera. FIG. 10 shows a contrast table 100 of spot images captured by the CCD camera and beam profiler 1, wherein the first row is the spots of the first control group beam 12; the second row is the spot of the second control group beam 12; the third row is the spot of the third control group beam 12; the first column is the image of the first to third control group beams 12 directly reaching the profiler 1; the fourth column is the image of the first to third contrast group beams 12 directly reaching the CCD camera; the second row is the images of the first to third control group beams 12 reaching the profiler 1 after being refracted by the lens 14 by the first angle; the fifth row is the images of the first to third contrast group beams 12 reaching the CCD camera after being refracted by the lens 14 at the first angle; the third row is the images of the first to third contrast group beams 12 reaching the profiler 1 after being refracted by the lens 14 at the second angle; the sixth row is the image of the first to third contrast beams 12, which reach the CCD camera after being refracted by the lens 14 at the second angle. It can be confirmed by comparison that the light spot captured by the CCD camera is not much different from the light spot captured by the beam profiler 1.

Fig. 11 shows the coordinate axis with the origin of the outward refraction of the light beam 12 through the lens 14 as the origin, and the axis perpendicular to the light receiving surface 22 as the z-axis. In some embodiments, the optical metrology system further comprises: the processing unit is in signal connection with the light receiving unit 20, and generates an imaginary plane 30 perpendicular to the optical axis 12L of the light beam 12, the data (shape and size) of the light spot on the imaginary plane 30 can be obtained by the data (shape and size) of the light spot obtained by the light receiving surface 22 and the angle α between the optical axis 12L and the z axis, and after the data (shape and size) of the light spot on the imaginary plane 30 of the light beam 12 is obtained, more data of the light beam can be calculated. For example, the threshold value of the spot (i.e., the spot diameter) may be calculated from the gaussian curve 125 of the spot as shown in fig. 12:where MaxValue is the maximum value of luminance and MinValue is the minimum value of luminance.

It should be noted that if the brightness after capturing the light spot by the CCD camera exceeds the maximum value (MaxValue), overexposure will occur, and the reasons for the overexposure include: the distance between the light receiving unit 20 and the light emitting unit 10 is too short, the light of the light beam 12 is too strong, and the camera shutter exposure time is long. When measuring the waist distance of the light beam 12, the minimum distance between the light receiving unit 20 and the light emitting unit 10 is approximately equal to the focal length of the light beam 12, so that the minimum distance between the two is dependent on the light beam 12 itself. Thus, the adjustable parameters include the brightness of the beam 12, the camera exposure time, and a light reducing mirror (Neutral Density) can be used to reduce the light entering the camera lens, attenuate the brightness value of the beam 12 (Numerical attenuation), and protect the CCD camera from damaging the shape of the light spot; in addition, the camera exposure time may be adjusted such that the camera exposure time is reduced.

In some embodiments, the processing unit is further configured to capture an image including the light beam 12, and divide the image into a plurality of sections (e.g., quadrants as shown in fig. 8). In some embodiments, the processing unit is further configured to calculate the angle α.

In some embodiments, the angle α is equal to the angle between the imaginary plane 30 and the light receiving surface 22 in fig. 11, that is, the processing unit is configured to calculate the angle between the imaginary plane 30 and the light receiving surface 22, and the z-axis is perpendicular to the light receiving surface 22, so that the processing unit is further configured to calculate the angle between the optical axis 12L of the light beam 12 and the light receiving surface 22.

After calculating the angle between the optical axis 12L and the z-axis of each beam 12, Δα between each two beams 12, that is, the difference between α between each two beams 12, can be calculated, and then it is verified whether the error between Δα and the standard data of the product is within an acceptable range. In some embodiments, the angle between the light-receiving surface 22 and the optical axis 12L of each light beam 12 is the same, i.e., Δα=0.

According to theory, the optical waist region 120 (see fig. 13) of the beam 12 is nonlinear, so a quadratic polynomial solution can be used to find the optical waist curve (y=cx ² +bx+a) and chemotaxisPotential line coefficients (a, b, c) and obtaining a waist focal length (Focal spot distance) of the light beam 12, wherein the distance between the waist position and the light emitting unit isThe diameter of the light waist isThe general form of the polynomial regression model is:

the matrix is expressed as:

in addition, the reliability of the curve calculated using the polynomial regression model can be verified: as shown in fig. 14, a standard gaussian spot of a light beam refracted by an Aberration-free converging lens (Aberration-free convergent lens) 143 of a laser source 142 captured by a CCD camera 141 is collected;

recording (e.g., using Excel) the diameter change of the spot at different distances from the laser source 142; analyzing a curve equation by using a polynomial regression model, and calculating the lowest point of the curve (namely the optical waist focal length) and the diameter of the light spot; measuring the diameter of the light spot by using a measuring instrument which is recognized in the industry, namely a beam profiler 1; and comparing the position of the focal length of the light spot measured and calculated by the light beam profiler 1 with a numerical value obtained by analysis and calculation by using a polynomial regression model, and judging whether the error is within a Specification (SPEC).

In summary, according to the embodiment of the present application, according to the light spot captured on the 2D plane, the data of the included angle β, the included angle α, the Δα, and the optical waist focal length can be obtained, and the operation is simple. In some embodiments, the light emitting unit 10 is moved at least 6 times relative to the light receiving unit 20. Including moving at least twice within the far field range of the beam 12 (away from the waist focal length) to obtain angles beta, alpha, delta alpha; but also four times within the near field range of the beam 12 (near the waist focal length, e.g. within 7-8mm from the light source) to obtain the waist focal length. The number of beams 12 is not limited, the number of beams 12 does not affect the number of movements, and individual beams 12 can be analyzed without calculating angles β, Δα when analyzing individual beams 12.

After obtaining the angle α between the optical axis 12L of each beam 12 and the z-axis (i.e. the normal of the light receiving surface 22), the six-axis platform 40 shown in fig. 3 may be used to drive the light emitting unit 10 to move, so that the optical axis 12L of the first beam 12 is perpendicular to the light receiving surface 22, so as to obtain the ellipticity and angular deviation/numerical aperture (Numerical Aperture, NA) of the light spot of the first beam 12.

Scheme two referring to fig. 15, in some embodiments, the optical metrology system further comprises: the other group of light receiving units 20' receives the plurality of light beams 12 emitted from the light emitting units 10 in a one-to-one correspondence. After the angle α between the optical axis 12L of each light beam 12 and the z-axis (i.e., the normal of the light receiving surface 22) is obtained, the light emitting unit 10 is removed from the six-axis platform 40 shown in fig. 3 and fixed below the light receiving units 20 'shown in fig. 15, and each light receiving unit 20' is moved so that the light receiving surfaces 22 'of the light receiving units 20' are perpendicular to the optical axis 12L of the light beam 12 in a one-to-one correspondence.

The first scheme has low development cost, only needs one industrial camera, can complete optical test in one station, can test as long as the light spot of the light-emitting unit 10 can enter the camera, does not need to change a mechanism, and the first scheme moves a product and is lighter than the second scheme, so that the CCD camera is not easy to vibrate after moving. The disadvantage of the first embodiment is that after the measurement of the first beam 12 is completed, the rotation is continued to make the next beam 12 perpendicular to the light receiving surface 22 until all the beams 12 are measured, which requires longer time than the second embodiment, and the throughput per hour (UPH) is low; the mechanism corrects the poor confirmation of the benchmark; the axis control action of the six-axis platform 40 is complex. In the second scheme, compared with the first scheme, the capacity per hour (UPH) is more, and the action of the axis control light receiving unit 20' is simpler; the disadvantage is that the module development cost is high, the more light receiving units 20' are required, the more the number of light receiving units 20' is equal to the number of light beams 12, the more the structural design is limited, the more difficult the mechanism of the light receiving units 20 relative to the light emitting units 10 is to correct the reference, the parameters in the optical test need to make the optical axis 12L of the light beams 12 and the state of the light receiving surface 22' of the light receiving units 20' orthogonal to each other to measure, and whether each optical axis 12L is orthogonal to the light receiving surface 22' cannot be determined.

In addition, it should be noted that the six-axis platform 40 is used to move the light-emitting unit 10, so that the stability can be improved and the vibration phenomenon can be reduced by shortening the cantilever connected with the light-emitting unit 10.

Embodiments of the present application also provide a method of using an optical metrology system:

the product placing platform is placed in the material feeding area and moved to the electrical testing station;

measuring the power and wavelength of the light emitting unit 10 using the integrating sphere 2, respectively;

moving the product to an optical test station, inputting a current to the product such that the light beam 12 is within a specified light intensity range;

image preprocessing, eliminating speckle noise, such as using a dimmer.

The image processing, the light receiving unit 20 captures images of light spots, wherein the images comprise two groups of images and more than two groups of images when the light receiving surface 22 is positioned in the far field of the light beam 12, coordinates of at least two points of the optical axis 12L of the light beam 12 are obtained, and four groups of images when the light receiving surface 22 is positioned in the near field of the light beam 12 are captured;

image processing, including dividing intervals and arranging light spots, and calculating single light spot parameters;

for two or more images of the light receiving surface 22 in the far field of the light beam 12, the connecting line belongs to the center of the light spots of the same light beam 12 to obtain an included angle beta, and the coordinates of the centers of the two light spots belonging to the same light beam 12 are used to obtain an included angle alpha;

when the light receiving surface 22 is located in the near field of the light beam 12, the processing unit generates an imaginary plane 30, and simulates the flare image on the imaginary plane 30 according to the flare image actually captured by the light receiving surface 22 and the included angle α;

the parameters of the light spot are recalculated based on the simulated image of the light spot on the imaginary plane 30: centroid, diameter (including major and minor axes);

the diameters of four light spots of the same light beam 12 after four near field movements are entered, the light waist curve of the light beam 12 is analyzed, curve coefficients are analyzed by using a polynomial regression model, and the coefficients are substituted into a formulaObtaining a light waist focal length;

rotating the light emitting unit 10 or moving another set of light receiving units 20 'according to the included angle α such that the light beam 12 is perpendicular (orthogonal) to the light receiving surface 22 or 22';

moving the light emitting unit 10 or the light receiving unit 20 'such that the light receiving surface 22 or 22' is located in the far field range of the light beam 12;

ellipticity, NA, beam quality factor M2 of the spot of beam 12 is calculated.

In the embodiment of the present application, the industrial camera (such as a CCD camera) is used to replace the beam profiler 1, so that the characteristics of multiple beams (such as laser beams) 12 can be measured at one time, the industrial camera obtains laser energy images, and the six-axis platform 40 is used to carry and move the light emitting unit 10 (moving along with the product) so that the product can move to each measuring position relative to the industrial camera, the parameters required by the measuring item can be deduced according to the physical characteristics of the light, and then the processing unit (algorithm) is matched to generate the imaginary plane 30, so that the non-orthogonal light spots are converted into orthogonal light spots, and the measuring data are classified corresponding to the light spots through image processing, so that the characteristics of the beams 12 can be measured by the industrial camera.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. An optical measurement system adapted to measure a light beam emitted from a light emitting unit, comprising:

the light receiving unit is used for receiving the light beam and acquiring an image of the light beam, the light receiving unit comprises a light receiving surface, the light receiving surface is not perpendicular to the optical axis of the light beam, and the light emitting unit moves relative to the light receiving unit.

2. The optical measurement system according to claim 1, wherein the light emitting unit includes a lens, and the optical axis of the light beam is not perpendicular to the light receiving surface after the light beam is refracted by the lens.

3. The optical measurement system according to claim 2, wherein the light receiving unit is configured to receive the plurality of light beams emitted by the light emitting unit, and optical axes of the plurality of light beams are not parallel to each other.

4. The optical measurement system of claim 2, wherein the angle between the light receiving surface and the optical axis of each of the light beams is the same.

5. The optical measurement system of claim 1, wherein the light receiving unit is stationary and the light emitting unit is movable.

6. The optical metrology system of claim 5, further comprising:

and the six-axis platform is used for bearing the light-emitting unit and controlling the light-emitting unit to move.

7. The optical metrology system of claim 1, further comprising:

the other group of light receiving units are used for receiving the light beams emitted by the light emitting units in a one-to-one correspondence mode.

8. The optical measurement system of claim 1, wherein the light emitting unit moves on a line between the light emitting unit and the light receiving unit.

9. The optical measurement system according to claim 1, wherein an angle between the light receiving surface and an optical axis of the light beam is constant when the light emitting unit moves relative to the light receiving unit.

10. The optical metrology system of claim 1, further comprising:

and the processing unit is in signal connection with the light receiving unit and generates an imaginary plane perpendicular to the light beam.