Galvanometer synchronous control method for optical detection

Abstract

The invention discloses a galvanometer synchronous control method for optical detection, and is applied to the technical field of optical detection. Comprising the following steps: acquiring an incident light angle adjustment range required in a current optical detection system; the incident light angle adjusting range serves as a detection angle sequence and is converted into an angle control sequence of an incident galvanometer; establishing a corresponding relation between an incident light angle and a reflected light angle, and obtaining an angle control sequence of a reflection galvanometer based on the angle control sequence of the incident galvanometer; based on the angle control sequences of the incidence galvanometer and the reflection galvanometer, angle control schemes of the incidence galvanometer and the reflection galvanometer are determined; converting the angle control scheme into a motor driving control signal; and synchronously controlling the incidence galvanometer and the reflection galvanometer based on the motor driving control signal. By designing the automatic galvanometer synchronous control method, the efficiency of adjusting the angle of the galvanometer is improved, and the method is suitable for an optical detection system which needs to frequently change the incident angle to carry out dynamic analysis.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical detection, more particularly, to a galvanometer synchronous control method for optical detection. BACKGROUND

[0002] In optical detection technologies such as surface plasmon resonance detection, it is often necessary to change the angle of incident light to measure data at different incident angles, for example, in surface plasmon resonance detection, the angle of SPR is calculated by changing the angle between the incident light and the normal and measuring the corresponding light intensity at different angles, which requires continuous and accurate control of the change of the incident light angle. In existing optical detection systems, the adjustment of the incident light angle is usually achieved by adjusting the prism or light source angle through a mechanical rotating table. This adjustment scheme takes a long time. The galvanometer scanning method is to use a galvanometer as an angle driving unit to achieve scanning within a certain angle range through the rotation of the galvanometer. However, in existing optical detection systems, manual adjustment of the incident light angle is required, especially for optical detection systems that simultaneously set incident galvanometers and reflecting galvanometers. Manual adjustment is complex and inefficient, which greatly affects the efficiency of optical detection. Therefore, how to provide a galvanometer synchronous control method for optical detection is a problem that needs to be solved by those skilled in the art. SUMMARY

[0003] Therefore, the present application provides a galvanometer synchronous control method for optical detection, which realizes automatic regulation and control of the galvanometer in the optical detection system.

[0004] In order to achieve the above purpose, the present application provides the following technical scheme:

[0005] A galvanometer synchronous control method for optical detection, comprising the following steps:

[0006] S1, obtaining the required incident light angle adjustment range in the current optical detection system;

[0007] S2, taking the incident light angle adjustment range as a detection angle sequence and converting it into an angle control sequence of the incident galvanometer;

[0008] S3, establishing a corresponding relationship between the incident light angle and the reflected light angle, and predicting the reflecting angle based on the angle control sequence of the incident galvanometer to obtain the angle control sequence of the reflecting galvanometer;

[0009] S4, determining the angle control scheme of the incident galvanometer and the reflecting galvanometer based on the angle control sequences of the incident galvanometer and the reflecting galvanometer;

[0010] S5, converting the angle control scheme into motor drive control signals of the incident galvanometer and the reflecting galvanometer;

[0011] S6, synchronously control the incident galvanometer and the reflecting galvanometer based on the motor driving control signal.

[0012] Optionally, S1 is specifically: analyzing the detection items of the optical detection system and determining the change of the incident light angle in the detection items, determining the incident light angle adjustment range based on the change of the incident light angle, and recording the node angle of the detection result.

[0013] Optionally, S2 is specifically: testing and recording the corresponding relationship between the deflection angle of the incident galvanometer and the incident angle, establishing an angle conversion lookup table, converting all the angles in the detection angle sequence into the corresponding incident galvanometer deflection angles in the angle conversion lookup table according to the relationship lookup table, and obtaining the angle control sequence of the incident galvanometer.

[0014] Optionally, S3 is specifically: testing and recording the reflecting angle θ out under different incident angles θ in , fitting the functional relationship between the incident angle θ out and the reflecting angle θ out : θ in =f(θ out ) based on the test data, obtaining the relationship between the reflecting angle θ I and the angle control sequence of the incident galvanometer based on the conversion relationship between the detection angle sequence and the angle control sequence of the incident galvanometer, and further determining the angle control sequence of the reflecting galvanometer.

[0015] Optionally, S5 is specifically: applying current to the coil through the galvanometer driving circuit, the size and direction of the current determine the strength and polarity of the magnetic field generated by the coil, the coil magnetic field interacts with the fixed magnetic field of the permanent magnet to generate Lorentz force, drive the coil and the reflecting mirror to rotate around the shaft to complete the galvanometer deflection, the deflection angle of the galvanometer is approximately linearly related to the driving current, and the current of the incident galvanometer driving circuit and the reflecting galvanometer driving circuit is determined based on the angle control scheme of the incident galvanometer and the reflecting galvanometer, to obtain the motor driving control signal.

[0016] Optionally, S6 is specifically: the controller generates the motor driving control signal of the incident galvanometer and the reflecting galvanometer, the motor driving control signal of the incident galvanometer and the reflecting galvanometer is generated by the same controller, the control timing is synchronized, the adjustment of the reflecting galvanometer is delayed and compensated, the angle adjustment response delay Δt of the reflecting galvanometer is measured, and the controller sends the motor driving control signal of the reflecting galvanometer Δt in advance.

[0017] Optionally, S6 further comprises:

[0018] S7, in the actual measurement process of the optical detection system, the control angle of the reflecting galvanometer is corrected according to the real-time detection data feedback of the detector.

[0019] Optionally, S7 is specifically:

[0020] S71, the detector of the optical system detects the reflected light intensity I1 in real time, and determines the optimal detection light intensity I2 of the optical system;

[0021] S72, the light intensity deviation value ΔI and the deviation rate e of the reflecting mirror are calculated I ;

[0022] S73, the light intensity deviation value ΔI and the deviation rate e of the reflecting mirror are input into the PID parameter calculation unit, and the PID parameter calculation unit outputs the control parameter correction value ΔK I ; P , ΔK I and ΔK D ;

[0023] S74, based on the control parameter initial value and the control parameter correction value ΔK P , ΔK I , ΔK D , the control parameter value K P , K I , K D is calculated:

[0024]

[0025] S75, based on the control parameter value K P , K I , K D , the reflection angle correction value Δθ out is calculated:

[0026]

[0027] S76, based on the reflection angle correction value Δθ out , the motor drive control signal of the reflecting mirror is regenerated and controlled.

[0028] Through the above technical solution, compared with the prior art, the present application provides a mirror synchronous control method for optical detection, which has the following beneficial effects: the present application designs an automatic mirror synchronous control method, which improves the efficiency of angle adjustment compared with the adjustment method of changing the physical light path in the existing detection system, and is especially suitable for optical detection systems that need to frequently change the incident angle for dynamic analysis. The synchronous control of the mirror ensures the accuracy of angle adjustment. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to make the technical solutions in the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only aim to explain part of the embodiments of the present application, and all other embodiments obtained by those of ordinary skill in the art without creative effort based on the provided accompanying drawings also belong to the protection scope of the present application.

[0030] Figure 1 The flow chart of the galvanometer synchronous control method of the present application;

[0031] Figure 2 The control angle correction schematic diagram of the reflecting galvanometer of the present application. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort also belong to the protection scope of the present application.

[0033] The embodiments of the present application disclose a galvanometer synchronous control method for optical detection, as shown in Figure 1 The method comprises the following steps:

[0034] S1, obtaining the required incident light angle adjustment range in the current optical detection system;

[0035] S2, taking the incident light angle adjustment range as the detection angle sequence, and converting it into the angle control sequence of the incident galvanometer;

[0036] S3, establishing the corresponding relationship between the incident light angle and the reflected light angle, and predicting the reflection angle based on the angle control sequence of the incident galvanometer to obtain the angle control sequence of the reflecting galvanometer;

[0037] S4, determining the angle control scheme of the incident galvanometer and the reflecting galvanometer based on the angle control sequences of the incident galvanometer and the reflecting galvanometer;

[0038] S5, converting the angle control scheme into the motor drive control signal of the incident galvanometer and the reflecting galvanometer;

[0039] S6, synchronously controlling the incident galvanometer and the reflecting galvanometer based on the motor drive control signal.

[0040] Further, S1 specifically comprises: analyzing the detection items of the optical detection system and determining the change of the incident light angle in the detection items, determining the incident light angle adjustment range based on the change of the incident light angle, and recording the node angle of the detection result. Further, S1 specifically comprises: analyzing the detection items of the optical detection system and determining the change of the incident light angle in the detection items, determining the incident light angle adjustment range based on the change of the incident light angle, and recording the node angle of the detection result.

[0041] Further, S2 is specifically: test and record the corresponding relationship between the deflection angle of the incident galvanometer and the incident angle, establish an angle conversion lookup table, convert all the angles in the detection angle sequence to the corresponding incident galvanometer deflection angles in the angle conversion lookup table according to the relationship lookup table, and obtain the angle control sequence of the incident galvanometer.

[0042] Further, S3 is specifically: test and record the reflection angle θ in under different incident angles θ out , fit the functional relationship between the incident angle θ in and the reflection angle θ out based on the test data: θ out =f(θ in ), obtain the relationship between the reflection angle θ out and the angle control sequence of the incident galvanometer based on the conversion relationship between the detection angle sequence and the angle control sequence of the incident galvanometer, and further determine the angle control sequence of the reflection galvanometer.

[0043] Further, S5 is specifically: the galvanometer driving circuit applies current to the coil, the current size and direction determine the strength and polarity of the magnetic field generated by the coil, the coil magnetic field interacts with the fixed magnetic field of the permanent magnet to generate Lorentz force, drive the coil and the mirror to rotate around the shaft to complete the galvanometer deflection, the deflection angle of the galvanometer and the driving current are approximately linearly related, the current of the incident galvanometer driving circuit and the reflection galvanometer driving circuit is determined based on the angle control scheme of the incident galvanometer and the reflection galvanometer, and the motor driving control signal is obtained.

[0044] Further, S6 is specifically: the controller generates the motor driving control signals of the incident galvanometer and the reflection galvanometer, the motor driving control signals of the incident galvanometer and the reflection galvanometer are generated by the same controller, the control timing is synchronized, the adjustment of the reflection galvanometer is delayed and compensated, the angle adjustment response delay Δt of the reflection galvanometer is measured, and the controller sends the motor driving control signal of the reflection galvanometer in advance by Δt time.

[0045] Further, S6 further includes:

[0046] S7, in the actual measurement process of the optical detection system, the control angle of the reflection galvanometer is corrected according to the real-time detection data of the detector.

[0047] Further, as shown in Figure 2 , S7 is specifically:

[0048] S71, the detector of the optical system detects the reflected light intensity I1 in real time, and determines the optimal detection light intensity I2 of the optical system;

[0049] S72, calculate the light intensity deviation value ΔI and the deviation rate e of the reflection galvanometerI ;

[0050] S73, the light intensity deviation value ΔI and the deviation rate e of the reflecting mirror are calculated I The input PID parameter calculation unit, the PID parameter calculation unit outputs the control parameter correction value ΔK P , ΔK I And ΔK D ;

[0051] S74, based on the control parameter initial value And the control parameter correction value ΔK P , ΔK I , ΔK D Calculate the control parameter value K P , K I , K D :

[0052]

[0053] S75, based on the control parameter value K P , K I , K D Calculate the reflection angle correction value Δθ out :

[0054]

[0055] S76, based on the reflection angle correction value Δθ out Regenerate the motor drive control signal of the reflecting mirror and control, dynamically adjust the reflecting mirror angle, make ΔI tend to zero.

[0056] In the embodiment of the application, the control parameter correction value ΔK P , ΔK I , ΔK D Based on fuzzy control algorithm, specifically:

[0057] First, determine the fuzzy subsets of the parameter variables ΔI, e I , ΔK P , ΔK I And ΔK D And membership functions, according to the control requirements of the reflecting mirror and the fuzzy subsets to establish fuzzy rule table, based on the fuzzy rule table to write specific fuzzy control rules.

[0058] Further, in an embodiment of the present application, the synchronization control in the system is based on a surface plasmon resonance detection system. Surface plasmons resonance (SPR) is a physical optical phenomenon, and using the SPR technology, the interaction between molecules, the formation of a thin film and other surface phenomena can be observed in real time. Surface plasmon (SP) refers to an electromagnetic wave propagating along the surface between a metal and a dielectric. When there is a metal film of tens of nanometers between the interface of the two media, the P-polarized component of the evanescent wave generated by total reflection enters the metal film and interacts with the free electrons in the metal film to generate surface plasmons. When the incident angle or the wavelength is at a certain appropriate value, the surface plasmons resonate with the evanescent wave, and the optical energy is absorbed, so that the reflected light energy sharply decreases. By changing the incident angle, the distribution diagram of the reflected light intensity and the incident angle can be obtained. In the embodiment, the surface plasmon resonance detection system is designed with two galvanometers, which are respectively used for adjusting the incident light and the reflected light. The incident galvanometer adjusts the incident angle according to the preset scanning mode, and the reflected galvanometer synchronously adjusts the receiving angle of the reflected light based on the change of the incident angle and the real-time reflected light intensity feedback.

[0059] According to the requirements of the surface plasmon resonance detection, the adjustment range of the incident light angle is determined as the incident angle ± 3°. According to the above range, the angle control sequence of the incident galvanometer is obtained. The surface plasmon resonance detection system is tested, and the function relationship between the incident angle θ in and the reflected angle θ out is fitted. In the embodiment, the theoretical value of the reflected angle can also be determined through optical path analysis. After the angle control scheme of the incident galvanometer and the reflected galvanometer is determined, the motors are driven based on the motor driving control signals, and the surface plasmon resonance detection is completed.

[0060] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the embodiments can be referred to each other.

[0061] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A galvanometer synchronous control method for optical detection, characterized in that: The following steps are involved: S1. Obtain the incident light angle adjustment range required in the current optical detection system; S2, taking the incident light angle adjustment range as the detection angle sequence and converting it into the angle control sequence of the incident galvanometer; S3, establishing a correspondence between the incident light angle and the reflected light angle, and predicting the reflected angle based on the angle control sequence of the incident galvanometer to obtain the angle control sequence of the reflective galvanometer; S4, determining an angle control scheme for the incident galvanometer and the reflective galvanometer based on the angle control sequence of the incident galvanometer and the reflective galvanometer; S5, converting the angle control scheme into motor drive control signals for the incident galvanometer and the reflective galvanometer; S6. Synchronously control the incident galvanometer and the reflective galvanometer based on the motor drive control signal.

2. The method for synchronous control of a galvanometer for optical detection according to claim 1, characterized in that: S1 specifically includes: analyzing the inspection items of the optical inspection system and determining the changes in the incident light angle in the inspection items, and determining the incident light angle adjustment range and the node angle for recording the inspection results based on the changes in the incident light angle.

3. The method for synchronous control of a galvanometer for optical detection according to claim 1, wherein: S2 specifically includes: testing and recording the corresponding relationship between the deflection angle of the incident galvanometer and the incident angle, establishing an angle conversion lookup table, and converting all angles in the detection angle sequence into the corresponding incident galvanometer deflection angles in the angle conversion lookup table according to the relationship lookup table to obtain the angle control sequence of the incident galvanometer.

4. The method for synchronous control of a galvanometer for optical detection according to claim 1, wherein: S3 is specifically: test and record at different incident angles θ in The reflection angle θ out , fitting the incident angle θ based on the test data in and reflection angle θ out Functional relationship: θ out =f(θ in ), the reflection angle θ is obtained according to the conversion relationship between the detection angle sequence and the angle control sequence of the incident galvanometer out The relationship between the angle control sequence of the incident galvanometer and the angle control sequence of the reflective galvanometer is used to determine the angle control sequence of the reflective galvanometer.

5. The method for synchronous control of a galvanometer for optical detection according to claim 1, characterized in that: S5 is specifically as follows: current is applied to the coil through the galvanometer drive circuit. The magnitude and direction of the current determine the strength and polarity of the magnetic field generated by the coil. The magnetic field of the coil interacts with the fixed magnetic field of the permanent magnet to generate a Lorentz force, driving the coil and the reflector to rotate around the axis to complete the galvanometer deflection. The deflection angle of the galvanometer is approximately linearly related to the drive current. Based on the angle control scheme of the incident galvanometer and the reflective galvanometer, the current of the incident galvanometer drive circuit and the reflective galvanometer drive circuit is determined to obtain the motor drive control signal.

6. The method for synchronous control of a galvanometer for optical detection according to claim 1, characterized in that: S6 is specifically as follows: the controller generates motor drive control signals for the incident galvanometer and the reflective galvanometer. The motor drive control signals for the incident galvanometer and the reflective galvanometer are generated by the same controller, the timing is controlled for synchronization, delay compensation is performed on the adjustment of the reflective galvanometer, the angle adjustment response delay Δt of the reflective galvanometer is measured, and the controller sends the motor drive control signal of the reflective galvanometer in advance by Δt.

7. A galvanometer synchronous control method for optical detection according to claim 6, characterized in that: S6 and later also include: S7. During the actual measurement process of the optical detection system, the control angle of the reflective galvanometer is corrected according to the real-time detection data feedback of the detector.

8. The method for synchronously controlling a galvanometer mirror for optical detection according to claim 7, wherein: S7 specifically: S71, the detector of the optical system detects the reflected light intensity I1 in real time and determines the optimal detection light intensity I2 of the optical system; S72. Calculate the light intensity deviation value ΔI and deviation rate e of the reflective galvanometer. I ; S73, the light intensity deviation value ΔI and the deviation rate e of the reflective galvanometer are calculated. I Input PID parameter calculation unit, PID parameter calculation unit output control parameter correction value ΔK P , ΔK I and ΔK D ; S74, based on the initial value of the control parameter and control parameter correction value ΔK P , ΔK I , ΔK D Calculate the control parameter value K P , K I , K D : S75, based on the control parameter value K P , K I , K D Calculate the reflection angle correction value Δθ out : S76, based on the reflection angle correction value Δθ out Regenerate the motor drive control signal of the reflective galvanometer and control it.

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