Optical position sensor, galvanometer system and position calibration method

Abstract

The invention provides an optical position sensor, a galvanometer system and a position calibration method. The optical position sensor comprises an upper light source module, a lower light source module and a signal triggering structure, the upper light source module is provided with a light source emitting module, and the light source emitting module is used for emitting light and focusing the light; the lower light source module and the upper light source module are oppositely arranged up and down, a gap is formed between the lower light source module and the upper light source module, the lower light source module comprises a light source receiving module, and the light source receiving module and the light source emitting module are oppositely arranged; the signal triggering structure is connected with the galvanometer system, one end of the signal triggering structure is provided with a triggering area, and the triggering area is located in the gap; wherein the focused light emitted by the light source emitting module penetrates through the trigger area to reach the light source receiving module to generate a calibration signal, and the calibration signal is used for calibrating the initial position of the galvanometer system. The precision reduction of the galvanometer system can be avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of galvanometer, in particular to an optical position sensor, a galvanometer system and a position calibration method. BACKGROUND

[0002] The laser galvanometer system is widely used in high-precision laser beam control in industrial applications such as laser welding, engraving, cutting and scanning. The laser galvanometer system mainly relies on a lightweight mirror installed on a precision motor to dynamically guide the laser beam with a precision of micro-radian level. The spatial position and rotation state of the galvanometer motor determine the actual propagation trajectory of the laser beam. However, environmental fluctuations during long-term operation can reduce the precision of the laser galvanometer system. For example, thermal deformation of motor components, temperature drift of encoders and thermal expansion and contraction of structures can all destroy the alignment relationship between the galvanometer motor shaft and the laser target plane, resulting in position errors. The errors are amplified through the transmission of the laser beam, and thus the high-precision requirements cannot be met. SUMMARY

[0003] The present application provides an optical position sensor, a galvanometer system and a position calibration method, aiming to solve the technical problem that the precision of the current galvanometer system gradually decreases.

[0004] In a first aspect, the present application provides an optical position sensor applied to a galvanometer system, which comprises an upper light source module, a lower light source module and a signal triggering structure. The upper light source module is provided with a light source emitting module for emitting and focusing light. The lower light source module is arranged opposite to the upper light source module and forms a gap with the upper light source module. The lower light source module comprises a light source receiving module arranged opposite to the light source emitting module. The signal triggering structure is connected with the galvanometer system and provided with a triggering area at one end, which is located in the gap. The focused light emitted by the light source emitting module passes through the triggering area and reaches the light source receiving module to generate a calibration signal for calibrating the initial position of the galvanometer system.

[0005] Further, the light source emitting module comprises a light emitting part and a focusing part. The light emitting part is arranged on one side of the upper light source module facing the lower light source module, and the focusing part is arranged directly below the light emitting part.

[0006] Further, the light source emitting module further comprises a reference receiving module arranged side by side with the light emitting part.

[0007] Further, the upper light source module is provided with a first installation space, the first installation space is respectively provided with the light emitting part, the focusing part and the reference receiving module, and the first installation space is also provided with an opening, and the opening is provided with the focusing part.

[0008] Further, the lower light source module is provided with a second installation space, the second installation space is provided with an opening relative to the focusing part, and the opening is provided with a receiving end of the light source receiving module.

[0009] Further, one end of the signal triggering structure is fixedly connected with the galvanometer system, the other end of the signal triggering structure is provided with a slit to form the triggering area, and the slit is used for allowing the light to pass through.

[0010] In a second aspect, the present application provides a galvanometer system, the galvanometer system comprises a first galvanometer device and a second galvanometer device, the first galvanometer device and the second galvanometer device are respectively provided with the optical position sensor of any one of the above, and the optical position sensor is used for calibrating the initial position of the first galvanometer device and the second galvanometer device.

[0011] Further, the first galvanometer device comprises a first motor, the output shaft of the first motor is provided with a first fixed component, the first fixed component is fixedly provided with a first reflecting mirror and a signal triggering structure of the optical sensor.

[0012] Further, the second galvanometer device comprises a second motor, the output shaft of the second motor is provided with a second fixed component, the second fixed component is fixedly provided with a second reflecting mirror and a signal triggering structure of the optical sensor.

[0013] In a third aspect, the present application provides a position calibration method, the position calibration method is used for calibrating the initial position of the galvanometer system of any one of the above, and the method comprises the following steps:

[0014] Confirming the light intensity peak value based on the calibration signal, and calculating the proportional coefficient of the galvanometer system based on the light intensity peak value;

[0015] Calculating the optical sensor angle based on the proportional coefficient, and acquiring the encoder feedback angle in real time;

[0016] Calculating the error correction parameter according to the optical sensor angle and the encoder feedback angle;

[0017] Compensating the encoder feedback angle based on the error correction parameter to realize the calibration of the initial position of the galvanometer system.

[0018] The galvanometer system disclosed by the application comprises a first galvanometer device, a second galvanometer device and an optical position sensor, the first galvanometer device and the second galvanometer device are both provided with the optical position sensor, the optical position sensor comprises an upper light source module, a lower light source module and a signal triggering structure, the upper light source module and the lower light source module are arranged oppositely, the signal triggering structure is located in the gap between the upper light source module and the lower light source module, the upper light source module is provided with a light source emitting module, the lower light source module is provided with a light source receiving module, the light emitted by the light source emitting module passes through the signal triggering structure after focusing and reaches the light source receiving module, thereby generating a calibration signal, and then the initial positions of the first galvanometer device and the second galvanometer device can be calibrated respectively to realize the calibration of the initial position of the galvanometer system. Meanwhile, the position calibration method disclosed by the application comprises confirming the light intensity peak value based on the calibration signal, and calculating the proportion coefficient of the galvanometer system based on the light intensity peak value; the optical sensor angle is calculated based on the proportion coefficient, and the encoder feedback angle is acquired in real time; the error correction parameter is calculated according to the optical sensor angle and the encoder feedback angle; the initial position of the galvanometer system is calibrated by compensating the encoder feedback angle based on the error correction parameter, the initial position can be confirmed based on the calibration signal to confirm the proportion coefficient, then the optical sensor angle is calculated based on the proportion coefficient, then the error correction parameter is calculated based on the optical sensor angle and the encoder feedback angle, and the initial position is calibrated by correcting the encoder feedback angle based on the error correction parameter, the deviation caused by temperature change, encoder error or structural thermal deformation can be inhibited, and the precision reduction can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0020] Figure 1 is the overall structure diagram of the galvanometer system provided by an embodiment of the present application;

[0021] Figure 2 is the assembly diagram of the second galvanometer device and the optical position sensor provided by an embodiment of the present application;

[0022] Figure 3 is the overall structure diagram of the second galvanometer device provided by an embodiment of the present application;

[0023] Figure 4 is the overall structure diagram of the optical position sensor provided by an embodiment of the present application;

[0024] Figure 5 is an exploded view of an optical position sensor provided by an embodiment of the present application;

[0025] Figure 6 is a curve diagram of angular displacement and output signal provided by an embodiment of the present application;

[0026] Figure 7 is a flowchart of a position calibration method provided by an embodiment of the present application.

[0027] BRIEF DESCRIPTION OF DRAWINGS: 1000, galvanometer system; 100, optical position sensor; 10, upper light source module; 11, light source emitting module; 12, light emitting piece; 13, focusing piece; 14, reference receiving module; 15, first mounting space; 20, lower light source module; 21, light source receiving module; 22, second mounting space; 30, signal triggering structure; 31, slit; 200, first galvanometer device; 210, first motor; 220, first fixed assembly; 230, first reflecting mirror; 300, second galvanometer device; 310, second motor; 320, second fixed assembly; 330, second reflecting mirror. DETAILED DESCRIPTION

[0028] 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. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0029] It should be understood that the terms “comprise” and “include” as used in the specification and the appended claims indicate the presence of the described features, integers, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, operations, elements, components, and / or groups thereof.

[0030] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, unless otherwise clearly indicated by the context, the singular forms “a”, “an” and “the” are intended to include the plural forms. It should be further understood that the term “and / or” as used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations thereof, and includes these combinations.

[0031] In addition, the direction terms mentioned in the present application, such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side", and the like, are only for reference to the directions of the attached drawings and the directions of the product in use. Therefore, the direction terms are used to illustrate and understand the present application, but not to limit the present application. In addition, in the drawings, the structures similar or identical to each other are denoted by the same reference numerals.

[0032] Referring to Figures 1 to 5 , Figure 1 is a whole structure diagram of a galvanometer system 1000 provided by an embodiment of the present application; Figure 2 is an assembly diagram of a second galvanometer device 300 and an optical position sensor 100 provided by an embodiment of the present application; Figure 3 is a whole structure diagram of the second galvanometer device 300 provided by an embodiment of the present application; Figure 4 is a whole structure diagram of the optical position sensor 100 provided by an embodiment of the present application; Figure 5 is an exploded view of the optical position sensor 100 provided by an embodiment of the present application. As shown in the figure, the optical position sensor 100 comprises an upper light source module 10, a lower light source module 20, and a signal triggering structure 30. The upper light source module 10 is provided with a light source emitting module 11, which is used to emit light and focus the light. The lower light source module 20 is arranged oppositely to the upper light source module 10 and forms a gap with the upper light source module 10. The lower light source module 20 comprises a light source receiving module 21, which is arranged oppositely to the light source emitting module 11. The signal triggering structure 30 is connected to the galvanometer system 1000, and one end of the signal triggering structure 30 is provided with a triggering area, which is located in the gap. The focused light emitted by the light source emitting module 11 passes through the triggering area and reaches the light source receiving module 21 to generate a calibration signal, which is used to calibrate the initial position of the galvanometer system 1000.

[0033] Specifically, the galvanometer system 1000 can comprise a first galvanometer device 200, a second galvanometer device 300, and an optical position sensor 100. The optical position sensor 100 is arranged on the first galvanometer device 200 and the second galvanometer device 300, and is used to calibrate the initial positions of the first galvanometer device 200 and the second galvanometer device 300 to calibrate the initial position of the galvanometer system 1000.

[0034] The optical position sensor 100 can include an upper light source module 10, a lower light source module 20, and a signal triggering structure 30. The upper light source module 10 and the lower light source module 20 are arranged opposite to each other. For example, the upper light source module 10 is located above the lower light source module 20, and a gap is left between the upper light source module 10 and the lower light source module 20. Part of the signal triggering structure 30, such as a triggering area of the signal triggering structure 30, is arranged in the gap. The upper light source module 10 is used to emit light, and the lower light source module 20 is used to receive light. The light emitted by the upper light source module 10 is received by the lower light source module 20 after passing through the signal triggering structure 30.

[0035] The upper light source module 10 can be provided with a light source emitting module 11. The light source emitting module 11 is used to emit light and focus the light. Meanwhile, the lower light source module 20 is provided with a light source receiving module 21. The light source receiving module 21 is used to receive the focused light and generate a calibration signal. The calibration signal is a compensation signal, which is essentially a voltage signal.

[0036] The signal triggering structure 30 is fixedly connected with the galvanometer system 1000. For example, the signal triggering structure 30 arranged on the first galvanometer device 200 is fixedly connected with the first galvanometer device 200, and the signal triggering structure 30 arranged on the second galvanometer device 300 is fixedly connected with the second galvanometer device 300. The first galvanometer device 200 and the second galvanometer device 300 each can include a galvanometer motor. The galvanometer motor can drive the signal triggering structure 30 to rotate. Taking the first galvanometer device 200 as an example, the signal triggering structure 30 can be connected with an output shaft of the galvanometer motor of the first galvanometer device 200. The galvanometer motor can drive the signal triggering structure 30 to rotate. When the signal triggering structure 30 rotates, the triggering area on the signal triggering structure 30 also rotates with the signal triggering structure 30, so that the light intensity can be adjusted. The triggering area is essentially an area through which light can pass. When the intersection area of the triggering area and the light is larger, the light intensity is larger. When the intersection area of the triggering area and the light is smaller, the light intensity is smaller. During the rotation of the galvanometer motor of the first galvanometer device 200, the light intensity also changes, and the calibration signal generated based on the light intensity also changes. The strongest light intensity can be set as the initial position of the galvanometer motor, which is the position of the output shaft of the galvanometer motor at 0°. It can be understood that the galvanometer motors on the first galvanometer device 200 and the second galvanometer device 300 are independent of each other. When the initial position is calibrated, the calibration needs to be performed separately.

[0037] In actual use, taking the first galvanometer device 200 as an example, the galvanometer motor driving signal trigger structure 30 of the first galvanometer device 200 rotates, the light source emitting module 11 emits light and focuses the light, the focused light irradiates to the signal trigger structure 30, when the trigger area of the signal trigger structure 30 deviates greatly from the path of the focused light, the focused light cannot pass through the signal trigger module, and the light source receiving module 21 cannot receive the focused light, when the trigger area intersects with the focused light, the focused light begins to pass through the trigger area and is received by the light source receiving module 21, the light intensity is converted into a voltage signal, that is, a calibration signal, with the rotation of the signal trigger structure 30, the light intensity gradually increases, when reaching the peak, the light intensity begins to decrease, until the focused light cannot pass through the trigger area, and the light intensity is zero. When the light intensity is maximum, the calibration signal at this time is recorded, and the angle of the galvanometer motor output shaft corresponding to the calibration signal at this time is 0°, thereby completing the calibration of the initial position of the galvanometer motor of the first galvanometer device 200. The calibration of the initial position of the second galvanometer device 300 can refer to the calibration of the first galvanometer device 200, and will not be described here.

[0038] As a further embodiment, the light source emitting module 11 comprises a light emitting piece 12 and a focusing piece 13; the light emitting piece 12 is arranged on one side of the upper light source module 10 facing the lower light source module 20, and the focusing piece 13 is arranged directly below the light emitting piece 12.

[0039] The light source emitting module 11 can comprise a light emitting piece 12 and a focusing piece 13 and a circuit assembly for supporting the work of the light emitting piece 12. The light emitting piece 12 can be a light emitting chip, such as an LED lamp or a laser diode, which can emit light. A focusing piece 13, which can be a convex lens, can be arranged directly below the light emitting piece 12 to focus the light emitted by the light emitting piece 12. A light source receiving module is arranged directly below the focusing piece 13, and the focused light can be directly received by the light source receiving module.

[0040] The focusing piece 13 is used to focus the light into a narrower light beam, and the narrowest part of the light beam is located at the focal point of the focusing piece 13. At the same time, the signal receiving structure can be in the same horizontal plane as the focal point of the focusing piece 13, and the light intensity at the focal point can be adjusted when the signal receiving structure rotates with the galvanometer motor. For example, the light at the focal point can be partially blocked to improve the position space resolution. When the galvanometer motor is at the initial position, that is, the output shaft of the galvanometer motor is at the 0° position, the trigger area of the signal receiving structure is directly opposite the focal point, at this time, the light beam passes through the slit 31 completely, and the light intensity signal received by the light source receiving module 21 is the strongest.

[0041] As a further embodiment, the light source emitting module 11 also includes a reference receiving module 14, which is arranged side by side with the light-emitting element 12.

[0042] The light source emitting module 11 may further include a reference receiving module 14, which is also used to receive light and is arranged side by side with the light source emitting module 11. Part of the light emitted by the light source emitting module 11 passes through the focusing element 13 and is received by the light source receiving module 21, while part is reflected back to the reference receiving module 14 through the internal surface of the light source emitting module 11. That is, the inner wall of the location where the light source emitting module 11 is installed needs to have a certain reflective capacity.

[0043] The reference receiving module 14 is in the same environment as the light-emitting element 12. Like the light-emitting element 12, it is affected by temperature. The reference receiving module 14 can provide a reference signal to eliminate the interference of ambient temperature on the signal. At the same time, the output of the light-emitting element 12 can be adjusted according to the reference signal to resist aging and degradation.

[0044] For example, when the galvanometer motor is in the initial position, the differential voltage of the optical position sensor is Vcomp0 = Vs - Vr, where Vs is the voltage signal of the light source receiving module 21, Vr is the reference signal of the reference receiving module 14, the theoretical encoder angle is θenc0 = 0°, then the proportional coefficient is k = θenc0 / Vcomp0 (in practice, it can be simplified to k = 0° / Vcomp0, which requires multi-point calibration fitting), and the true angle of the galvanometer motor is θoptic = k × Vcomp.

[0045] As a further embodiment, the upper light source module 10 is provided with a first mounting space 15, in which the light-emitting element 12, the focusing element 13 and the reference receiving module 14 are respectively provided, and the first mounting space 15 is also provided with an opening, at which the focusing element 13 is provided.

[0046] The light source module may have a first mounting space 15, within which a light-emitting element 12, a focusing element 13, and a reference receiving module 14 are respectively arranged. Figure 5 As shown, a light-emitting element 12 and a reference receiving module 14 can be arranged side by side on the top of the first mounting space 15. A fixing plate is provided below the light-emitting element 12, and an opening is opened on the fixing plate directly below the light-emitting element 12. A focusing element 13 is fixed in the opening. It is understood that the inner wall of the first mounting space 15 needs to have a certain reflective ability to facilitate the reflection of light back to the reference receiving module 14.

[0047] As a further embodiment, the lower light source module 20 is provided with a second mounting space 22, the second mounting space 22 having an opening relative to the focusing member 13, and the receiving end of the light source receiving module 21 is provided at the opening.

[0048] The lower light source module 20 may be provided with a second mounting space 22, which has an opening directly below the focusing element 13. The receiving end of the light source receiving module 21 is located at the opening. The focused light emitted by the light source emitting module 11 can be received by the light source receiving module 21 through the receiving end of the light source receiving module 21, thereby generating a calibration signal.

[0049] As a further embodiment, one end of the signal triggering structure 30 is fixedly connected to the galvanometer system 1000, and the other end of the signal triggering structure 30 is provided with a slit 31 to form the triggering area, the slit 31 being used for the light to pass through.

[0050] The signal triggering structure 30 can be an arc-shaped plate. The inner side of the arc-shaped plate is fixedly connected to the galvanometer system 1000, for example, it can be connected to the first galvanometer device 200 and the second galvanometer device 300. A slit 31 is formed on the outer side of the arc-shaped plate. The slit 31 can be a U-shaped groove for light to pass through. The angle range can be adjusted by adjusting the size of the slit 31 and the distance between the slit 31 and the focal point.

[0051] like Figure 6 As shown, Figure 6 The graph shows the relationship between light intensity and angle. When slit 31 is directly opposite the focal point, the transmittance is 100%, and the light intensity signal 1 reaches its peak, such as 3V, corresponding to the initial 0° position of the output axis. Light intensity signal 1 represents the 0° initial position, where the resolution is highest, the beam diameter at the focal point is smallest (micrometer level), and the slope of the light intensity change is steep, achieving microradian-level resolution (approximately 0.1μrad). When slit 31 deviates from the focal point, the light intensity decreases, such as dropping to 2.0V at light intensity signal 2 and to 1.0V at light intensity signal 3, thus expanding the angle detection range. The angle range can be adjusted by changing the size of slit 31 and its distance from the focal point. For example, a narrow slit with close distance results in a small range and high resolution, while a wide slit with far distance results in a large range and low resolution.

[0052] The application further provides a galvanometer system 1000, which comprises a first galvanometer device 200 and a second galvanometer device 300, and each of the first galvanometer device 200 and the second galvanometer device 300 is provided with the optical position sensor 100 in any one of the above embodiments, which is used for calibrating the initial positions of the first galvanometer device 200 and the second galvanometer device 300 respectively; the optical position sensor 100 comprises an upper light source module 10, a lower light source module 20 and a signal triggering structure 30; the upper light source module 10 is provided with a light source emitting module 11, which is used for emitting light rays and focusing the light rays; the lower light source module 20 is arranged oppositely to the upper light source module 10 and a gap is formed between the upper light source module 10 and the lower light source module 20, and the lower light source module 20 comprises a light source receiving module 21, which is arranged oppositely to the light source emitting module 11; the signal triggering structure 30 is connected with the galvanometer system 1000, and one end of the signal triggering structure 30 is provided with a triggering area, which is located in the gap; wherein the focused light rays emitted by the light source emitting module 11 pass through the triggering area and reach the light source receiving module 21 to generate a calibration signal, which is used for calibrating the initial position of the galvanometer system 1000.

[0053] Specifically, the galvanometer system 1000 can comprise a first galvanometer device 200, a second galvanometer device 300 and an optical position sensor 100, and the optical position sensor 100 is arranged on each of the first galvanometer device 200 and the second galvanometer device 300, which is used for calibrating the initial positions of the first galvanometer device 200 and the second galvanometer device 300 to realize the calibration of the initial position of the galvanometer system 1000.

[0054] The optical position sensor 100 can comprise an upper light source module 10, a lower light source module 20 and a signal triggering structure 30, and the upper light source module 10 and the lower light source module 20 are arranged oppositely, for example, the upper light source module 10 is located above, the lower light source module 20 is located below the upper light source module 10, and a gap is left between the upper light source module 10 and the lower light source module 20, and part of the signal triggering structure 30, for example, a triggering area of the signal triggering structure 30, is arranged in the gap. The upper light source module 10 is used for emitting light rays, the lower light source module 20 is used for receiving light rays, and the light rays emitted by the upper light source module 10 are received by the lower light source module 20 after passing through the signal triggering structure 30.

[0055] The upper light source module 10 can be provided with a light source emitting module 11, which is used for emitting light and focusing the light. Meanwhile, the lower light source module 20 is provided with a light source receiving module 21, which is used for receiving the focused light and generating a calibration signal, which is a compensation signal and is essentially a voltage signal.

[0056] The signal triggering structure 30 is fixedly connected with the galvanometer system 1000, for example, the signal triggering structure 30 on the first galvanometer device 200 is fixedly connected with the first galvanometer device 200, and the signal triggering structure 30 on the second galvanometer device 300 is fixedly connected with the second galvanometer device 300. The first galvanometer device 200 and the second galvanometer device 300 can each include a galvanometer motor, which can drive the signal triggering structure 30 to rotate. Taking the first galvanometer device 200 as an example, the signal triggering structure 30 can be connected with the output shaft of the galvanometer motor of the first galvanometer device 200, and the galvanometer motor can drive the signal triggering structure 30 to rotate. When the signal triggering structure 30 rotates, the triggering area on the signal triggering structure 30 also rotates with the signal triggering structure 30, so that the light intensity can be adjusted. The triggering area is essentially an area through which light can pass. When the intersection area of the triggering area and the light is larger, the light intensity is larger, and when the intersection area of the triggering area and the light is smaller, the light intensity is smaller. During the rotation of the galvanometer motor of the first galvanometer device 200, the light intensity also changes, and the calibration signal generated based on the light intensity also changes. The strongest light intensity can be set as the initial position of the galvanometer motor, which is the position of the output shaft of the galvanometer motor at 0°. It can be understood that the galvanometer motors on the first galvanometer device 200 and the second galvanometer device 300 are independent of each other, and the calibration of the initial position needs to be calibrated separately.

[0057] In actual use, taking the first galvanometer device 200 as an example, the galvanometer motor driving signal trigger structure 30 of the first galvanometer device 200 rotates, the light source emitting module 11 emits light and focuses the light, the focused light irradiates to the signal trigger structure 30, when the trigger area of the signal trigger structure 30 deviates greatly from the path of the focused light, the focused light cannot pass through the signal trigger module, and the light source receiving module 21 cannot receive the focused light, when the trigger area intersects with the focused light, the focused light begins to pass through the trigger area and is received by the light source receiving module 21, the light intensity is converted into a voltage signal, that is, a calibration signal, with the rotation of the signal trigger structure 30, the light intensity gradually increases, when reaching the peak, the light intensity begins to decrease, until the focused light cannot pass through the trigger area, and the light intensity is zero. When the light intensity is maximum, the calibration signal at this time is recorded, and the angle of the galvanometer motor output shaft corresponding to the calibration signal at this time is 0°, and the calibration of the initial position of the galvanometer motor of the first galvanometer device 200 is completed. The calibration of the initial position of the second galvanometer device 300 can refer to the calibration of the first galvanometer device 200, which will not be described here.

[0058] As a further embodiment, the first galvanometer device 200 includes a first motor 210, a first fixed component 220 is arranged on the output shaft of the first motor 210, a first mirror 230 and a signal trigger structure 30 of the optical sensor are fixed on the first fixed component 220. As a further embodiment, the second galvanometer device 300 includes a second motor 310, a second fixed component 320 is arranged on the output shaft of the second motor 310, a second mirror 330 and a signal trigger structure 30 of the optical sensor are fixed on the second fixed component 320.

[0059] Wherein, the structure of the first galvanometer device 200 and the second galvanometer device 300 is similar, the first galvanometer device 200 can include a first motor 210, a first fixed component 220 and a first mirror 230, the second galvanometer device 300 can include a second motor 310, a second fixed component 320 and a second mirror 330, the difference lies in that the sizes of the first mirror 230 and the second mirror 330 are different. Taking the second galvanometer device 300 as an example, the optical position sensor 100 can be fixed on the shell of the second motor 310, the signal trigger structure 30 of the optical position sensor 100 can be fixed on the second fixed component 320, and the second fixed component 320 is fixed on the output shaft of the second motor 310, at the same time, the second mirror 330 is also fixed on the second fixed component 320, when the second motor 310 drives the output shaft to rotate, it can synchronously drive the second mirror 330 and the signal trigger structure 30 to rotate.

[0060] The application further provides a position calibration method for calibrating the initial position of the galvanometer system according to any one of the above embodiments, as shown in the following. Figure 7 The position calibration method comprises the following steps:

[0061] S110, confirming the light intensity peak based on the calibration signal, and calculating the scale factor of the galvanometer system based on the light intensity peak.

[0062] In the embodiment of the application, the calibration signal is related to the light intensity. When the output shaft of the galvanometer motor is at the initial position, i.e., at the 0° position, the light intensity is the largest, and the corresponding calibration signal is the largest. At this time, the differential voltage Vcomp0 of the optical position sensor is recorded, i.e., Vcomp0=Vs-Vr, Vs is the voltage signal of the light source receiving module, Vr is the reference signal of the reference receiving module, the theoretical angle θenc0 of the encoder is 0°, and the scale factor k is θenc0 / Vcomp0.

[0063] S120, calculating the optical sensor angle based on the scale factor, and acquiring the feedback angle of the encoder in real time.

[0064] In the embodiment of the application, the optical sensor angle θoptic=k×Vcomp, and Vcomp0=Vs-Vr, so the optical sensor angle θoptic=k×(Vs-Vr), and the feedback angle of the encoder is θencoder.

[0065] S130, calculating the error correction parameter based on the optical sensor angle and the feedback angle of the encoder.

[0066] In the embodiment of the application, the error correction parameter Δθ=θoptic-θencoder. When Δθ is greater than 0, the encoder angle lags behind the real position, indicating that there may be bearing wear, reverse clearance, and when Δθ is less than 0, the encoder angle leads the real position, indicating that there may be encoder thermal expansion drift.

[0067] S140, compensating the feedback angle of the encoder based on the error correction parameter to realize the calibration of the initial position of the galvanometer system.

[0068] In the embodiment of the application, when Δθ is not equal to 0, it indicates that the feedback angle of the encoder needs to be corrected, and the corrected angle θencoder_new=θencoder+Δθ. During the operation of the galvanometer system, when it is detected that the error correction parameter Δθ is not 0, the angle can be calibrated, or the angle can be calibrated after a certain interval of time.

[0069] The application can confirm the initial position based on the calibration signal to confirm the scale factor, then calculate the optical sensor angle based on the scale factor, then calculate the error correction parameter based on the optical sensor angle and the encoder feedback angle, and correct the encoder feedback angle based on the error correction parameter to realize the calibration of the initial position, so that the deviation caused by temperature change, encoder error or structural thermal deformation can be inhibited, and the precision reduction can be avoided.

[0070] The above is only a specific embodiment of the application, but the protection scope of the application is not limited thereto, and any person skilled in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the application, and these modifications or replacements should be covered within the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. An optical position sensor, characterized in that, The optical position sensor, used in a galvanometer system, includes: The upper light source module is equipped with a light source emitting module, which is used to emit light and focus the light. The lower light source module is arranged vertically opposite to the upper light source module and forms a gap between them. The lower light source module includes a light source receiving module, which is arranged opposite to the light source emitting module. A signal triggering structure is connected to the galvanometer system, and one end of the signal triggering structure is provided with a triggering area located within the gap; The light emitted by the light source emitting module, after being focused, passes through the trigger area and arrives at the light source receiving module to generate a calibration signal, which is used to calibrate the initial position of the galvanometer system.

2. The optical position sensor as described in claim 1, characterized in that, The light source emitting module includes a light-emitting component and a focusing component; The light-emitting element is located on the side of the upper light source module facing the lower light source module, and the focusing element is located directly below the light-emitting element.

3. The optical position sensor as described in claim 2, characterized in that, The light source emitting module also includes a reference receiving module, which is arranged side by side with the light-emitting element.

4. The optical position sensor as described in claim 3, characterized in that, The upper light source module is provided with a first installation space, in which the light-emitting element, the focusing element and the reference receiving module are respectively provided, and the first installation space is also provided with an opening, at which the focusing element is provided.

5. The optical position sensor as described in claim 2, characterized in that, The lower light source module is provided with a second mounting space, and the second mounting space has an opening relative to the focusing element. The opening is provided with the receiving end of the light source receiving module.

6. The optical position sensor as described in claim 1, characterized in that, One end of the signal triggering structure is fixedly connected to the galvanometer system, and the other end of the signal triggering structure has a slit to form the triggering area, the slit being used for the light to pass through.

7. A galvanometer system, characterized in that, The galvanometer system includes a first galvanometer device and a second galvanometer device, both of which are equipped with an optical position sensor as described in any one of claims 1-6. The optical position sensor is used to calibrate the initial positions of the first galvanometer device and the second galvanometer device, respectively.

8. The galvanometer system as described in claim 7, characterized in that, The first galvanometer device includes a first motor, a first fixing component is provided on the output shaft of the first motor, and a first reflector and the signal triggering structure of the optical sensor are fixed on the first fixing component.

9. The galvanometer system as described in claim 7, characterized in that, The second galvanometer device includes a second motor, a second fixing component is provided on the output shaft of the second motor, and a second reflector and the signal triggering structure of the optical sensor are fixed on the second fixing component.

10. A position calibration method, characterized in that, The position calibration method is used to calibrate the initial position of the galvanometer system as described in any one of claims 7-9, and the position calibration method includes: The peak light intensity is confirmed based on the calibration signal, and the scaling factor of the galvanometer system is calculated based on the peak light intensity. The optical sensor angle is calculated based on the scaling factor, and the encoder feedback angle is obtained in real time. The error correction parameters are calculated based on the optical sensor angle and the encoder feedback angle. The encoder feedback angle is compensated based on the error correction parameters to calibrate the initial position of the galvanometer system.

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