TW201923473A - Galvanometer correction system and method - Google Patents

Abstract

Provided in the present invention are a galvanometer correction system and method, which is implemented by means of the following steps: S1: causing the optical axis of a galvanometer to move along a first horizontal direction and a second horizontal direction respectively by means of changing the swinging angle of the galvanometer in a galvanometer scanning system so as to form a plurality of light spots within a field corresponding to the galvanometer, and measuring and recording the position of the plurality of light spots by means of a light spot position measurement device; S2: substituting data measured by the light spot position measurement device in an overlay model within the field to obtain an error parameter within a current galvanometer field; S3: calculating an error amount within a galvanometer field to be compensated according to the error parameter of the current galvanometer field, the error amount within the galvanometer field comprising an error amount in a first horizontal direction and an error amount in a second horizontal direction; S4: correcting the galvanometer scanning system by means of a galvanometer controller according to the error amount in the first horizontal direction and the error amount in the second horizontal direction that are obtained in S3, controlling the corrected galvanometer scanning system to re-scan and re-form a plurality of light spots, detecting and determining the precision of the plurality of re-formed light spots, and repeating steps S1 to S3 if precision is not satisfactory; stopping repetition of the steps and finishing error correction within the field if precision is satisfactory.

Description

   Galvanometer correction system and method   

The invention belongs to the field of scanning devices and relates to a galvanometer correction system and method.

Before use and after installation, the galvanometer needs to undergo a certain correction, and then obtain a certain amount of compensation data, so that it can be scanned more accurately during use.

Manual correction is used in the existing correction methods, so errors in the manual correction process are easy to occur, and the correction effect is poor.

The object of the present invention is to provide a galvanometer correction system and method, which aims to solve the problem of poor correction effect.

In order to solve the above technical problems, the present invention provides a galvanometer correction system including a galvanometer scanning system, a galvanometer controller, a gantry, a focusing device, a detection and sampling system, and a spot position measuring device. The galvanometer scanning system includes Mirror, the focusing device is used to focus the light beam emitted through the galvanometer, the detection and sampling system is used to achieve alignment between the spot position measuring device and the galvanometer, and the galvanometer controls The galvanometer is used to control the movement of the galvanometer to form multiple light spots in the field corresponding to the galvanometer. The galvanometer scanning system can move along the gantry in a first horizontal direction and can follow the gantry in the Move vertically.

Optionally, the galvanometer correction system further includes a water-cooling system, and the water-cooling system is used for water-cooling and cooling the galvanometer scanning system.

Optionally, the spot position measuring device is a profiler.

Optionally, the galvanometer correction system further includes a workpiece table capable of moving in a second horizontal direction, wherein the second horizontal direction is perpendicular to the first horizontal direction, and the spot position measuring device is connected On the upper or side of the workpiece table.

Optionally, the workpiece stage is used to drive the spot position measuring device to move so as to measure the spot position.

Optionally, a plurality of the galvanometer scanning systems are provided on the gantry.

Optionally, the galvanometer correction system further includes a laser device for providing an incident beam to the galvanometer scanning system.

Optionally, the focusing device is a flat field focusing lens (F-theta lens).

In order to solve the above technical problem, the present invention also provides a galvanometer correction method using the galvanometer correction system, including the following steps: S1: By changing the swing angle of the galvanometer in the galvanometer scanning system, the light of the galvanometer is changed. The axes move in the first horizontal direction and the second horizontal direction, respectively, so that a plurality of light spots are formed in the field corresponding to the galvanometer, and the spot position measuring device measures and records the positions of the plurality of light spots; S2: the light spots The data measured by the position measuring device is substituted into the intra-overset model to obtain the current in-field galvanometer error parameter; S3: the amount of in-field galvanometer error to be compensated is calculated based on the current in-field galvanometer parameter. The error amount includes a first horizontal direction error amount and a second horizontal direction error amount; S4: through the galvanometer controller, according to the first horizontal direction error amount and the second horizontal direction error amount obtained in S3, The galvanometer scanning system performs correction, and controls the galvanometer scanning system to perform rescanning and re-formation of multiple light spots, and to re-form the multiple light spots formed. And determining the detection accuracy, as accuracy does not satisfy S1 to S3 are repeated; such accuracy meets the stop step is repeated, to complete the field of error correction.

Optionally, the intra-field overlay model in S2 is as follows: △ x = Mx . x - Ry . y + Tx

△ y = My . y + Rx . x + Ty

Among them, △ x and △ y : deviations between the actual imaging position of the light spot in the horizontal direction and the nominal position in the first horizontal direction and the second horizontal direction; x , y : light spots set by the galvanometer controller Tx , Ty : translation of the actual imaging position and nominal position of the spot in the galvanometer field in the first horizontal direction and the second horizontal direction; Mx , My : actual imaging size of the spot in the galvanometer field The magnification of the nominal imaging size relative to the spot in the first horizontal direction and the second horizontal direction; Rx , Ry : the actual imaging position and nominal position of the spot in the galvanometer field are in the first horizontal direction and Rotation in the second horizontal direction; n = M × N light spots were measured in the test, where M and N are natural numbers. For n light spots, the intra-field overlay model is transformed into a matrix form:

The least square method is used to obtain the current errors Tx , Ty , Mx , My , Rx , Ry in the galvanometer field.

Optionally, the first horizontal direction error amount and the second horizontal direction error amount in S3 include a compensation amount of the optical axis of the galvanometer at a nominal position of each spot, and are expressed as: DeltaX ( y ) = △ x - Tx -0.5. ( Rx + Ry ). y

DeltaY ( x ) = △ y - Ty -0.5. ( Rx + Ry ). x .

Alternatively, the galvanometer scanning system performs multiple spot position measurements at each specific measurement position, and averages multiple spot position data for calculation in S3.

Optionally, the galvanometer correction method further includes the following steps: S5: The position of the optical axis of the galvanometer of the galvanometer scanning system is maintained unchanged, and the galvanometer scanning system is performed on the gantry. For the first horizontal movement, each step is projected by the galvanometer scanning system multiple times, and the spot position measuring device is used to measure the light spot projected at each step position on the gantry. Position x _{i , j} , y _{i , j in the} zero coordinate system, where i = 1,2, ..., n is the number of steps and j = 1,2, ..., m is each step The number of times the spot is projected at the advanced position; S6: Keep the position of the galvanometer scanning system unchanged, so that the optical axis of the galvanometer is in the first horizontal direction to perform spot projection in the field at various measurement positions. The spot position measuring device measures the horizontal positions x ' _{i , j} , y' _{i , j} of each spot projected at each measurement position under the zero coordinate system of the gantry, where i = 1,2, .. ., n is the number of measurement positions, j = 1,2, ..., m is the number of light spots projected at each measurement position; S7: S6 The nominal position is the same as the nominal position in S5, which are respectively x_nom _i , y_nom _i . In S5 and S6, the galvanometer scanning system performs m exposures at each position, and samples the light spot at each position. Data average:

The above sampling data is substituted into the following formula to perform the least square method fitting, and the galvanometer installation rotation amount is k :

Among them, b is a constant; S8: The galvanometer controller is used to correct the galvanometer scanning system according to the galvanometer installation rotation amount obtained in S7, and the corrected galvanometer scanning system is rescanned and restarted. A plurality of light spots are formed, and the newly formed light spots are detected and judged for accuracy. If the accuracy is not satisfied, repeat S5 to S7. If the accuracy is satisfied, stop repeating the steps to complete the installation rotation correction.

Compared with the prior art, the present invention provides a galvanometer correction system and method. During the correction, the galvanometer scanning system is determined at a specific measurement position (determined by the position of the optical axis of the galvanometer, which can be understood as the nominal position. ) Use the deflection angle of the galvanometer to form multiple light spots in the field corresponding to the measurement position, and calculate the relationship between the measured positions and the nominal positions of the multiple light spots, so as to obtain the field of the galvanometer scanning system. The error compensation amount is calculated after the compensation amount is calculated, thereby verifying the correctness of the compensation amount. The present invention also uses a similar measurement, calculation, and accounting process to correct the installation rotation error of the galvanometer, which not only eliminates the The errors existing in the correction can be guaranteed, and the accuracy of the compensation amount can be guaranteed after verification, which is highly practical.

1‧‧‧ galvanometer scanning system

2‧‧‧ Galvanometer Controller

3‧‧‧laser equipment

4‧‧‧ Gantry

5‧‧‧ flat-field focusing lens (F-theta lens)

6‧‧‧ Detection and sampling system

7‧‧‧Spot position measuring device

8‧‧‧ water cooling system

9‧‧‧Workbench

10‧‧‧First correction spot

11‧‧‧second correction spot

12‧‧‧ third correction spot

13‧‧‧ Fourth correction spot

1 is a schematic diagram of a correction method in the present invention; FIG. 2 is a schematic diagram of a correction system in the present invention; FIG. 3 is a schematic diagram of compensation amount feedback in the present invention; and FIG. Schematic diagram; Figure 5 is a schematic diagram of the galvanometer scanning system of the present invention at S5 and S6; Figure 6 is a structural diagram of the spot position measuring device of the present invention is located on the side of the workpiece table; Figure 7 is the spot position in the embodiment of the present invention The calculated theoretical value of the deviation in the x-direction and the y-direction; FIG. 8 is a spot distortion variable measured after the F-theta calculation value is imported into the compensation amount in the embodiment of the present invention; FIG. 9 is a light spot in the embodiment of the present invention The actual distortion curve after the position is calibrated; FIG. 10 is a schematic structural diagram of a plurality of galvanometer scanning systems connected to a gantry.

A galvanometer correction system and method provided by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and the scope of patent application. It should be noted that the drawings are in a very simplified form and all use inaccurate proportions, which are only used to facilitate and clearly assist the description of the embodiments of the present invention.

Galvanometer is one of the commonly used parts in laser processing technology. It can be used in combination with laser equipment, F-theta mirror, etc. to achieve laser scanning of the workpiece to be processed. The galvanometer usually has a flat surface and can swing within a certain range of angles with respect to its central axis. The function of the galvanometer is, for example, to reciprocate the laser beam emitted by the laser device along a predetermined path. However, due to factors such as the working environment and installation accuracy, the actual working performance of the galvanometer may not meet the expected requirements, so it is necessary to correct the galvanometer.

To this end, the present invention provides a galvanometer correction system and method. In a specific embodiment, a galvanometer used in a laser processing process is described as an example. Therefore, a light source device is described as a laser in the following embodiments. Device, describing the focusing device as an F-theta lens. However, those skilled in the art should understand that other light source equipment and / or other focusing devices can also be used to achieve galvanometer correction, and the present invention should not be limited to this.

As shown in FIG. 1 to FIG. 3, a galvanometer correction system according to a specific embodiment includes a galvanometer scanning system 1, a galvanometer controller 2, a laser device 3, a gantry 4, an F-theta mirror 5, and detection sampling. System 6 and spot position measuring device 7, the F-theta mirror 5 is used to focus the light beam emitted from the galvanometer scanning system 1, and the detection and sampling system 6 is used to implement the spot position measuring device 7 and the galvanometer scanning system 1. For example, the position of the alignment mark on the substrate carried by the workpiece table 9 can be sampled by the detection and sampling system 6 to obtain the first positional relationship of the spot position measuring device 7 with respect to the substrate. 6 The second positional relationship (which is a known quantity) relative to the galvanometer scanning system 1 results in the positional relationship of the spot position measuring device 7 relative to the galvanometer scanning system 1 to achieve alignment. The galvanometer controller 2 controls the galvanometer scanning system 1 to scan, so that the galvanometer in the galvanometer scanning system 1 is at one or more specific measurement positions (determined by the position of the optical axis of the galvanometer, which can be understood as the nominal position ) The light source and the deflection angle of the galvanometer are used to form one or more light spots. The galvanometer scanning system 1 is installed on the gantry 4 and can move along the gantry 4 in the x direction. The z-direction movement is performed with the gantry 4, where z is a vertical direction. The galvanometer is mounted on the gantry 4 such that the central axis extends in the y direction, where the x direction and the y direction are two directions perpendicular to each other in the horizontal plane.

Galvanometer correction includes in-field error correction and galvanometer installation rotation correction.

The correction of the galvanometer field error includes the following steps: S1: The swing angle of the galvanometer of the galvanometer scanning system 1 causes the optical axis of the galvanometer (that is, the optical axis of the light emitted through the galvanometer) to sequentially dot in the x direction and the y direction. That is, the optical axis of the galvanometer and the xy plane form an intersection point, so that a plurality of light spots are formed in the field corresponding to the galvanometer. The spot position measuring device 7 measures and records the positions of all light spots generated by the galvanometer scanning system 1. As shown, a plurality of first correction spots 10 are obtained in the x-direction scanning, and a plurality of second correction spots 11 are obtained in the y-direction scanning; S2: the first correction spots 10 and the second correction spots 11 measured by the position measuring device 7 The position data of the camera is substituted into the in-field overlay model to obtain the in-field error parameters of the current galvanometer; S3: the x- and y-direction compensation amounts of the galvanometer are calculated to compensate the in-field error of the galvanometer; S4: galvanometer control The scanner 2 compensates the galvanometer scanning system 1 according to the x-direction and y-direction compensation amounts obtained in S3, and uses the compensated galvanometer scanning system 1 to rescan and form a light spot (ie, repeat S1), Detection and accuracy judgment of the formed light spot (Ie repeat S2), if the accuracy is not satisfied, calculate the compensation amount again (ie repeat S3). The above S1 to S3 can be repeated multiple times until the accuracy meets the requirements, then the repeating steps are stopped to complete the field error correction.

The in-field overlay model in S2 is as follows: △ x = Mx . x - Ry . y + Tx △ y = My . y + Rx . x + Ty .............. (2-1)

In the above formula, △ x and △ y are the deviations of the actual imaging position of the light spot in the horizontal direction (that is, the position measured by the position measuring device 7) and the nominal position (that is, the position set by the galvanometer controller 2) in the x and y directions. ; X , y : the nominal position of the spot set by the galvanometer controller; Tx , Ty : the actual imaging position of the spot in the galvanometer field is translated in the x and y directions relative to the nominal position; Mx , My : the galvanometer Magnification of the actual imaging size of the spot in the field with respect to the nominal imaging size of the spot in the x and y directions; Rx , Ry : rotation of the actual imaging position of the spot in the galvanometer field relative to the nominal position in the x and y directions; In the test, a total of n = M × N light spots are measured, where M and N are natural numbers. For n light spots, (2-1) is transformed into a matrix form:

The least square method is used for fitting to obtain the in-field errors Tx , Ty , Mx , My , Rx , Ry of the current galvanometer.

The compensation amount of the galvanometer in S3 is as follows, that is, the compensation amount of the optical axis of the galvanometer scanning system at each x , y position is: DeltaX ( y ) = △ x - Tx -0.5. ( Rx + Ry ). y DeltaY ( x ) = △ y - Ty -0.5. ( Rx + Ry ). x ..................... (2-3).

The galvanometer scanning system 1 successively forms several light spots at each measurement position in the x direction and the y direction, and averages the position data of the several light spots for calculation in S3.

The galvanometer installation rotation correction includes the following steps: S5: Keep the position of the optical axis of the galvanometer scanning system 1 unchanged, that is, by keeping the galvanometer at a fixed swing angle, the optical axis of the galvanometer and the xy plane The included angle remains the same. The galvo scanning system 1 performs an x-direction movement on the gantry 4. Each step, the galvo scanning system 1 projects a light spot, and uses a light spot position measuring device 7 to measure a single projection position at a single measurement position. The position of the generated light spot under the zero coordinate system of gantry 4 x _{i , j} , y _{i , j} , where i = 1, 2, ..., n is the number of exposure marks, which can be increased at each measurement position The spot projection is repeated twice, so that a plurality of measurement values at the measurement position are obtained by the spot position measuring device 7, and the number of measurements is represented by j, j = 1, 2, ..., m . As shown in FIG. 5, in the x-direction, several third correction spots 12 on the same horizontal line are obtained; S6: the position of the galvanometer scanning system 1 is kept unchanged, and the light of the galvanometer is realized by the vibration of the galvanometer. The axis scans in the x direction to form a plurality of light spots in the x direction. The light spot position measuring device 7 is used to measure the horizontal direction of each light spot formed by the galvanometer scanning system 1 during the above-mentioned swing process in the zero coordinate system of the gantry 4 Positions x ' _{i , j} , y' _{i , j} , where i is the number of light spots formed by the galvanometer at different positions, and j is the number of measurements by the light spot position measuring device 7 at each light spot position to obtain several fourths Correction spot 13; S7: The nominal position of the spot in S6 is the same as the nominal position in S5, and they are x_nom _i , y_nom _i , respectively. In S5 and S6, the galvanometer scanning system 1 performs m times of spots at each measurement position. Projection, and average the sampled data of each spot:

The above sampling data is substituted into the following formula to perform the least square method fitting, and the galvanometer installation rotation amount is k :

Where b is a constant.

S8: Substitute the galvanometer installation rotation amount obtained in S7 back to the galvanometer controller 2 for controlling the galvanometer scanning system to re-scan and form a light spot, and detect and accurately judge the newly formed light spot. If the accuracy is not satisfied, repeat S5 to S7, stop if it is satisfied, and complete the installation of rotation correction.

As shown in FIG. 7, in this embodiment, the galvanometer system theoretically calculates a calibration deviation curve in the x-direction and the y-direction. FIG. 8 is a calculation in which a known F-theta deviation value is substituted, and The theoretical calibration deviation curve of the y direction, and FIG. 9 is the actual deviation chart of the light spot in this embodiment. As can be seen from the figure, the light spot can reach a certain accuracy in both the x direction and the y direction after the correction adjustment is performed. , And the actual accuracy needs to be set and calibrated according to the actual situation.

Preferably, the spot position measuring device 7 is a profiler; and further includes a water cooling system 8 for cooling the galvanometer scanning system 1 with water, and the water cooling temperature of the water cooling system 8 is 20 ° C-24 ℃, this embodiment is preferably 22 ℃.

The galvanometer correction system described in this embodiment further includes a workpiece table 9 that moves in the y-direction, and can realize relative movement of the galvanometer scanning system 1 relative to the workpiece on the workpiece table 9 in the y-direction. The spot position measuring device 7 is optionally connected to the upper or side of the work table 9. When the spot position measuring device 7 is located on the side of the work table 9, as shown in FIG. 6, both the galvanometer can be corrected The system does not affect the galvanometer scanning system 1 to perform laser processing on the workpiece on the workpiece table 9 after the galvanometer is calibrated, and the practicability is strong.

The gantry 4 can also be provided with a plurality of galvanometer scanning systems 1, as shown in FIG. 10, so that multiple groups of galvanometer scanning systems 1 can be processed at the same time. Among them, several galvanometer scanning systems 1 can be the same as the same. One laser device 3 can be connected to the laser device 3, and different galvanometer scanning systems 1 can be connected to the same galvanometer controller 2 or different galvanometer controllers. 2 connection, adjust according to the actual situation.

When correcting different types of galvanometer systems, you can choose one of each type of galvanometer system for calibration and get compensation data, and then get the compensation data and feed it back to the galvanometer controller 2. The other galvanometer systems in this class can be directly verified, so that the labor intensity and calibration time of correcting the galvanometer can be greatly reduced in the actual operation process.

In summary, the galvanometer correction system and method provided by the present invention, when the galvanometer scanning system is corrected, the galvanometer in the galvanometer scanning system uses a laser device at one or more specific measurement positions. The deflection angle of the emitted light source and the galvanometer forms the first correction spot and the second correction spot, and calculates the position between the formed spot and the nominal position, thereby forming an actual compensation between the actual spot position and the nominal position. This eliminates errors in the manual correction and adjustment process, and the adjustment effect is good, and because each light spot is obtained by averaging several light spots, this also reduces accidental errors and makes the number of compensation amounts It can make the actual spot position closer to the nominal position; the compensation amount is the compensation amount of the overall galvanometer scanning system, and after the third and fourth correction spots are also used to compensate the installation rotation of the lens, the A better compensation amount is obtained. Similarly, the position of m light spots is also calculated in the compensation calculation of lens deflection. After averaging and calculating with the nominal position, it can also reduce accidental errors.

The galvanometer scanning system will increase in temperature during the working process, which will easily cause temperature drift and lead to the spot position measurement device, that is, the profiler's insensitivity to the light spot. In this way, the galvanometer scanning system can be water-cooled by the water cooling system. It is better to make the galvanometer scanning system maintain a more suitable sensing temperature. In this embodiment, 22 ° C is used. Under the premise of constant temperature, the error caused by temperature drift can be minimized, so that the calculation of the compensation amount can be more For accuracy.

It should be noted that each embodiment in this specification is described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments may refer to each other. As for the test method disclosed in the embodiment, since the test device adopted by the embodiment corresponds to the device portion disclosed in the embodiment, the description of the test device involved therein is relatively simple. For the relevant part, refer to the description of the device portion.

The above description is only a description of the preferred embodiments of the present invention, and does not limit the scope of the present invention in any way. Any changes and modifications made by those skilled in the art in accordance with the above disclosure are within the protection scope of the patent application.

Claims (13)

    A galvanometer correction system is characterized by comprising a galvanometer scanning system, a galvanometer controller, a gantry, a focusing device, a detection and sampling system, and a spot position measuring device. The galvanometer scanning system includes a galvanometer and the focusing device. The galvanometer is used to focus the light beam emitted through the galvanometer, the detection and sampling system is used to achieve alignment between the spot position measuring device and the galvanometer, and the galvanometer controller is used to control the vibration The movement of the mirror is to form a plurality of light spots in a field corresponding to the galvanometer. The galvanometer scanning system can move along the gantry in a first horizontal direction and can follow the gantry to move in a vertical direction.         The galvanometer correction system according to claim 1, further comprising a water cooling system, which is used for cooling the galvanometer scanning system with water.         The galvanometer correction system according to claim 1, wherein the spot position measuring device is a profiler.         The galvanometer correction system according to claim 1, further comprising a workpiece table capable of moving in a horizontal second direction, wherein the second horizontal direction is perpendicular to the first horizontal direction, and the spot position is measured. The device is connected to an upper part or a side part of the workpiece table.         The galvanometer correction system according to claim 4, wherein the workpiece stage is used to drive the spot position measuring device to move to realize the measurement of the spot position.         The galvanometer correction system according to claim 1, wherein a plurality of the galvanometer scanning systems are provided on the gantry.         The galvanometer correction system according to claim 1, further comprising a laser device for providing an incident beam to the galvanometer scanning system.         The galvanometer correction system according to claim 1, wherein the focusing device is a flat field focusing lens (F-theta lens).         A galvanometer correction method using the galvanometer correction system of any one of claims 1 to 8 is characterized in that it includes the following steps: S1: By changing the swing angle of the galvanometer in the galvanometer scanning system, the vibration The optical axis of the mirror is moved in the first horizontal direction and the second horizontal direction, respectively, so that a plurality of light spots are formed in the field corresponding to the galvanometer, and the spot position measuring device measures and records the positions of the multiple light spots; S2: The data measured by the light spot position measuring device is substituted into the intra-overset model to obtain the current in-field galvanometer error parameter; S3: the amount of in-field galvanometer error to be compensated is calculated according to the current in-field galvanometer parameter, and the vibration The error amount in the mirror field includes a first horizontal direction error amount and a second horizontal direction error amount; S4: through the galvanometer controller, according to the first horizontal direction error amount and the second horizontal direction error obtained in S3 Correct the galvanometer scanning system, control the corrected galvanometer scanning system to rescan and re-form multiple light spots, and detect the newly formed multiple light spots Analyzing and precision, such precision is not satisfied S1 to S3 are repeated; such accuracy meets the stop step is repeated, to complete the field of error correction.     For example, the galvanometer correction method of item 9, wherein the in-field overcut model in S2 is as follows: △ x = Mx . x - Ry . y + Tx △ y = My . y + Rx . x + Ty , △ x , △ y : the deviation between the actual imaging position of the light spot in the horizontal direction and the nominal position in the first horizontal direction and the second horizontal direction; x , y : by the galvanometer controller Set the nominal position of the spot; Tx , Ty : translation of the actual imaging position and nominal position of the spot in the galvanometer field in the first horizontal direction and the second horizontal direction; Mx , My : the The magnification of the actual imaging size relative to the nominal imaging size of the light spot in the first horizontal direction and the second horizontal direction; Rx , Ry : the actual imaging position and nominal position of the light spot in the galvanometer field are in the first horizontal direction And the rotation in the second horizontal direction; a total of n = M × N light spots are measured in the test, where M and N are natural numbers, and for the n light spots, the intra-field overlay model is transformed into a matrix form: The least square method is used to obtain the current errors Tx , Ty , Mx , My , Rx , Ry in the galvanometer field. The galvanometer correction method of claim 10, wherein the first horizontal error amount and the second horizontal error amount in S3 include a compensation amount of the optical axis of the galvanometer at a nominal position of each light spot, Expressed as: DeltaX ( y ) = △ x - Tx -0.5. ( Rx + Ry ). y DeltaY ( x ) = △ y - Ty -0.5. ( Rx + Ry ). x .     For example, the galvanometer correction method according to item 11, wherein the galvanometer scanning system performs multiple spot position measurements at each specific measurement position, and averages multiple spot position data for calculation in S3.     If the galvanometer correction method of item 11 is further included, the method further includes the following steps: S5: Keep the position of the optical axis of the galvanometer of the galvanometer scanning system unchanged in the field, and the galvanometer scanning system is on the gantry. The first horizontal direction movement is performed, and each step is performed by the galvanometer scanning system to project a plurality of light spots, and the light spot position measuring device is used to measure each light spot projected at each step position on the gantry The positions x _{i , j} , y _{i , j} in the zero coordinate system of the frame, where i = 1,2, ..., n is the number of steps and j = 1,2, ..., m is each The number of times the spot is projected at each step position; S6: keeping the position of the galvanometer scanning system unchanged, so that the optical axis of the galvanometer is in the first horizontal direction to perform spot projection in the field at each measurement position, Using the spot position measuring device to measure the horizontal positions x ' _{i , j} , y' _{i , j} of each spot projected at each measurement position under the zero coordinate system of the gantry, where i = 1,2, ..., n is the number of measurement locations, j = 1,2, ..., m is the number of measurements at each projected light spot; S7: S6 in Name of the same nominal position and the position of the spot S5 are respectively x_nom _i, y_nom _i, S5 and S6, the galvanometer scanning system are m times exposure at each position, and every spot Average the sampled data: The above sampling data is substituted into the following formula to perform the least square method fitting, and the galvanometer installation rotation amount is k : Among them, b is a constant; S8: The galvanometer controller is used to correct the galvanometer scanning system according to the galvanometer installation rotation amount obtained in S7, and the corrected galvanometer scanning system is rescanned and restarted. A plurality of light spots are formed, and the newly formed light spots are detected and judged for accuracy. If the accuracy is not satisfied, repeat S5 to S7. If the accuracy is satisfied, stop repeating the steps to complete the installation rotation correction.