Monochromator wavelength error calibration device and calibration method

Abstract

The application provides a monochromator wavelength error calibration device and a calibration method. The monochromator wavelength error calibration device comprises an ultrashort pulse laser, a monochromator, an interference assembly, a detector, an imaging unit and a control processor. The monochromator is connected with the laser. The interference assembly is arranged on a sinusoidal driving mechanism of the monochromator. The interference assembly is used for interfering monochromatic light output by the monochromator to generate interference fringes. The detector is used for collecting the interference fringes and displaying the interference fringes on the imaging unit. The control processor is connected with the monochromator. The control processor is used for driving the sinusoidal driving mechanism of the monochromator to repeatedly move and calibrating wavelength error of the monochromator according to changes of the interference fringes on the imaging unit. The technical scheme of the application is used to solve the technical problems that wavelength calibration error of the monochromator is large and the whole wavelength band cannot be calibrated in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical instrument calibration technology, and in particular to a monochromator wavelength error calibration device and method. BACKGROUND

[0002] The monochromator has important application in the spectral radiometric calibration of sensors. Before use, the wavelength accuracy and output spectral bandwidth of the monochromator need to be accurately calibrated. In the laboratory calibration of the monochromator, a characteristic spectral line lamp (such as a low-pressure mercury lamp) or a laser is often used as a light source, a photomultiplier tube is used as a receiving instrument, and the characteristic spectral line of the mercury lamp (or the center wavelength of the laser) is used as a reference wavelength for wavelength calibration. The output wavelength of the monochromator is evaluated and calibrated by actually measuring and analyzing the differences between the multiple spectral lines of the low-pressure mercury lamp and the indicated wavelength of the monochromator. At other uncalibrated wavelengths, algorithms are often used for derivation or interpolation. In the periodic calibration process of the monochromator, wavelength calibration is usually performed under a certain typical state. However, in the actual calibration application of the monochromator for sensors, the input and output slits of the monochromator need to be adjusted according to the spectral channel characteristics of the equipment to be calibrated, and the output bandwidth of the monochromator needs to be changed, which may affect the output wavelength accuracy of the monochromator.

[0003] Errors inevitably exist in the processing and installation of the monochromator, and the monochromator must be calibrated before use. Traditionally, the calibration method using a mercury lamp has a limited number of wavelengths, which limits the calibration accuracy of the monochromator. Based on the principle of a grating monochromator, a monochromator calibration method based on a continuous spectrum light source is proposed, and a calibration experimental system is designed and built. The system is composed of a supercontinuum laser, a light source power supply, a filter, a monochromator, a spectrometer, and a computer. A halogen lamp is used as a light source, and a spectrometer is used to measure the radiation of the halogen lamp after passing through the monochromator and directly measure the radiation of the halogen lamp. The transmittance function of the monochromator is obtained by comparing the two, eliminating the influence of the radiation of the halogen lamp and the response function of the spectrometer. At a certain reading position of the scale disc, the transmittance function of the monochromator is obtained and normalized, and the peak wavelength is calculated to obtain a set of peak wavelength and scale disc reading data. However, the wavelength calibration error of the monochromator is large in this way, and only the sharp peaks of the spectral line lamp can be used to calibrate the discrete points of the monochromator, and the entire wavelength band cannot be calibrated. SUMMARY

[0004] The present application provides a monochromator wavelength error calibration device and method, which can solve the technical problem of large wavelength calibration error and inability to calibrate the entire wavelength band in the prior art.

[0005] According to an aspect of the present application, a monochromator wavelength error calibration device is provided, comprising: a supercontinuum laser; a monochromator connected with the supercontinuum laser; an interference assembly arranged on a sinusoidal driving mechanism of the monochromator, the interference assembly being used for interfering monochromatic light output by the monochromator to generate interference fringes; a detector and an imaging unit, the detector being used for collecting the interference fringes and displaying on the imaging unit; and a control processor connected with the monochromator, the control processor being used for driving the sinusoidal driving mechanism of the monochromator to move repeatedly and calibrating wavelength error of the monochromator according to changes of the interference fringes on the imaging unit.

[0006] Further, the interference assembly comprises a reference corner cube reflector, a beam splitter and a target corner cube reflector, the monochromator comprises a monochromator body and a sinusoidal driving mechanism, the reference corner cube reflector and the beam splitter are arranged on the monochromator body, and the target corner cube reflector is arranged on the sinusoidal driving mechanism, the sinusoidal driving mechanism being used for driving the target corner cube reflector to move.

[0007] Further, the interference assembly further comprises a compensation plate arranged on the sinusoidal driving mechanism, the compensation plate being arranged in parallel with the beam splitter, and the compensation plate being used for improving definition of an interference image.

[0008] Further, the monochromator wavelength error calibration device further comprises a frequency-doubling crystal arranged between the supercontinuum laser and the monochromator, the frequency-doubling crystal being used for modulating laser emitted by the supercontinuum laser into laser of a set frequency and wavelength.

[0009] Further, the monochromator wavelength error calibration device further comprises a first optical fiber collimating lens arranged between the supercontinuum laser and the frequency-doubling crystal, the first optical fiber collimating lens being used for collimating laser emitted by the supercontinuum laser.

[0010] Further, the monochromator wavelength error calibration device further comprises a first optical fiber converging lens arranged between the frequency-doubling crystal and the monochromator, the first optical fiber converging lens being used for converging laser output by the frequency-doubling crystal.

[0011] Further, the monochromator wavelength error calibration device further comprises a second optical fiber collimating lens arranged between the first optical fiber converging lens and an entrance slit of the monochromator, the second optical fiber collimating lens being used for collimating laser output by the first optical fiber converging lens.

[0012] Further, the monochromator wavelength error calibration device further comprises a second optical fiber converging lens, the second optical fiber converging lens is arranged between the exit slit of the monochromator and the interference assembly, and the second optical fiber converging lens is used for converging the monochromatic light output by the monochromator; and / or the monochromator wavelength error calibration device further comprises a third optical fiber collimating lens, the third optical fiber collimating lens is arranged between the second optical fiber converging lens and the interference assembly, and the third optical fiber collimating lens is used for collimating the monochromatic light output by the second optical fiber converging lens.

[0013] Further, the sine drive mechanism comprises a motor, a rotating shaft, a sliding block, a swing rod and a grating seat, the motor is used for driving the rotating shaft to rotate, the sliding block is threadedly connected with the rotating shaft, the rotating shaft can drive the sliding block to move in a straight line, one end of the swing rod is abutted with the sliding block, the sliding block can drive the swing rod to swing, and the other end of the swing rod is connected with the grating seat, and the grating seat is rotatably arranged on the monochromator body.

[0014] According to another aspect of the present application, a monochromator wavelength error calibration method is provided, the monochromator wavelength error calibration method comprises: arranging an interference assembly on a sine drive mechanism of a monochromator; the interference assembly interferes monochromatic light output by the monochromator to generate interference fringes; a detector receives the interference fringes and displays the interference fringes on an imaging unit; and a control processor drives the sine drive mechanism of the monochromator to repeatedly move and calibrates wavelength error of the monochromator according to changes of the interference fringes on the imaging unit.

[0015] The technical scheme of the present application provides a monochromator wavelength error calibration device, the error calibration device generates a laser beam with a set spectral range by using an ultra-continuous spectrum laser, the ultra-continuous spectrum laser beam enters a monochromator and outputs monochromatic light, an interference assembly interferes the monochromatic light to generate interference fringes, a detector collects the interference fringes and displays the interference fringes on an imaging unit, and a control processor drives a sine drive mechanism of the monochromator to repeatedly move and calibrates wavelength error of the monochromator according to changes of the interference fringes on the imaging unit, in this way, by arranging the interference assembly on the sine drive mechanism, according to the designed interference assembly, errors of one quarter of a wavelength generated by the sine drive mechanism of the monochromator are all reflected as changes in brightness of the interference fringes, through analysis by the detector and the control processor, the error of the sine drive mechanism of the monochromator can be accurately determined to one tenth of a wavelength. Therefore, compared with the prior art, the error calibration device provided by the present application greatly improves the calibration accuracy of the sine drive mechanism and effectively solves the technical problem of large wavelength calibration error of the monochromator. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is understood that the drawings are for purposes of illustrating the concepts of the application and are not intended to limit the scope of the application. It is further understood that the drawings can not be to scale and that, unless otherwise specifically mentioned, the drawings are merely intended to conceptually illustrate one or more embodiments of the application.

[0017] Figure 1 Fig. 1 shows a structural schematic diagram of a monochromator wavelength error calibration device according to a first embodiment of the present application;

[0018] Figure 2 Fig. 2 shows a structural schematic diagram of a monochromator wavelength error calibration device according to a second embodiment of the present application;

[0019] Figure 3 Fig. 3 shows a structural schematic diagram of a sine drive mechanism according to a specific embodiment of the present application;

[0020] Figure 4 Fig. 4 shows a schematic diagram of an interference assembly according to a specific embodiment of the present application.

[0021] In the above drawings, the following reference numerals are used:

[0022] 10, supercontinuum laser; 20, monochromator; 21, monochromator body; 21a, entrance slit; 21b, exit slit; 22, sine drive mechanism; 221, motor; 222, rotating shaft; 223, sliding block; 224, swing rod; 225, grating holder; 226, roller; 227, grating; 228, grating shaft; 229, spring; 30, interference assembly; 31, reference corner cube reflector; 32, beam splitter; 33, target corner cube reflector; 34, compensation plate; 40, detector; 50, imaging unit; 60, control processor; 70, frequency doubling crystal; 80, first fiber collimating lens; 90, first fiber converging lens; 100, second fiber collimating lens; 110, second fiber converging lens; 120, third fiber collimating lens; 130, lens. DETAILED DESCRIPTION

[0023] It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other in the case of no conflict. The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation to the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work under the premise that there is no conflict, belong to the scope of protection of the present application.

[0024] It should be noted that the terms used herein are only intended to describe specific embodiments and are not intended to limit exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and it should be understood that, when the terms "comprise" and / or "include" are used in the specification, it indicates the presence of the features, steps, operations, devices, components and / or combinations thereof.

[0025] Unless specifically stated otherwise, the relative arrangement of the components and steps illustrated in these embodiments do not limit the scope of the present application. It should be understood that the sizes of the various portions shown in the drawings are not necessarily to scale. Techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as part of the description of the present application. In all examples shown and discussed herein, any specific value should be interpreted as merely illustrative, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0026] As Figure 1 and Figure 2As shown, the specific embodiment according to the present application provides a monochromator wavelength error calibration device, which comprises a supercontinuum laser 10, a monochromator 20, an interference assembly 30, a detector 40, an imaging unit 50 and a control processor 60, the monochromator 20 is connected with the supercontinuum laser 10, the interference assembly 30 is connected with the monochromator 20, the interference assembly 30 is used for interfering monochromatic light output by the monochromator 20 to generate interference fringes, the detector 40 is used for collecting the interference fringes and displaying on the imaging unit 50, the control processor 60 is connected with the monochromator 20, and the control processor 60 is used for driving the sinusoidal driving mechanism 22 of the monochromator 20 to move repeatedly and calibrating the wavelength error of the monochromator 20 according to the change of the interference fringes on the imaging unit 50.

[0027] By using this configuration, a monochromator wavelength error calibration device is provided, which generates a laser beam with a set spectral range by a supercontinuum laser, the laser beam enters a monochromator and outputs monochromatic light, an interference assembly interferes the monochromatic light to generate interference fringes, a detector collects the interference fringes and displays on an imaging unit, and a control processor drives the sinusoidal driving mechanism of the monochromator to move repeatedly and calibrates the wavelength error of the monochromator according to the change of the interference fringes on the imaging unit. In this way, by arranging the interference assembly on the sinusoidal driving mechanism, according to the designed interference assembly, the error of the sinusoidal driving mechanism of the monochromator in a quarter wavelength is reflected as the light and dark change of the interference fringes, and through the analysis of the detector and the control processor, the error of the sinusoidal driving mechanism of the monochromator can be accurately to one-tenth of the wavelength, and the wavelength error calibration of the entire waveband can be realized. Therefore, compared with the prior art, the error calibration device provided by the present application greatly improves the calibration accuracy of the sinusoidal driving mechanism, can realize the wavelength error calibration of the entire waveband, and effectively solves the technical problems that the monochromator wavelength calibration error is large and the entire waveband error calibration cannot be realized.

[0028] Further, in the present application, in order to be able to realize the interference of the monochromatic light output by the monochromator 20, the interference assembly 30 can be configured to comprise a reference corner cube reflector 31, a beam splitter 32 and a target corner cube reflector 33, the monochromator 20 comprises a monochromator body 21 and a sinusoidal driving mechanism 22, the reference corner cube reflector 31 and the beam splitter 32 are arranged on the monochromator body 21, and the target corner cube reflector 33 is arranged on the sinusoidal driving mechanism 22, and the sinusoidal driving mechanism 22 is used to drive the target corner cube reflector 33 to move.

[0029] In this configuration, as shown in FIG. 2, the reference corner cube reflector 31 and the beam splitter 32 are arranged on the monochromator body 21, and the target corner cube reflector 33 is arranged on the sinusoidal driving mechanism 22. Figure 4As shown, the supercontinuum laser generates a laser beam of a set spectral range, the laser beam enters the monochromator and outputs monochromatic light, the monochromatic light is split in the beam splitter 32 of the interference assembly 30, one of the beams enters the reference corner cube reflector and is reflected by the reference corner cube reflector to enter the detector, the other beam enters the target corner cube reflector and is emitted by the target corner cube reflector to enter the detector, in the process, the target corner cube reflector moves in a straight line direction, thereby completing the interference of the monochromatic light and generating interference fringes.

[0030] Specifically, in the present application, in order to drive the target corner cube reflector to move in a straight line direction, as shown in the drawings, Figure 3 The sine drive mechanism 22 can be configured to include a motor 221, a rotating shaft 222, a sliding block 223, a swing rod 224 and a grating seat 225, the motor 221 is used to drive the rotating shaft 222 to rotate, the sliding block 223 is threadedly connected with the rotating shaft 222, the rotating shaft 222 can drive the sliding block 223 to move in a straight line direction, one end of the swing rod 224 abuts against the sliding block 223, the sliding block 223 can drive the swing rod 224 to swing, the other end of the swing rod 224 is connected with the grating seat 225, and the grating seat 225 is rotatably arranged on the monochromator body 21.

[0031] In this configuration, the motor 221 drives the rotating shaft to rotate, the rotating shaft drives the sliding block to move in a straight line direction, the sliding block movement drives the swing rod to swing, and further drives the grating seat to swing. By arranging the target corner cube reflector on the sliding block, the sliding block movement can drive the corner cube reflector to move in a straight line direction. As a specific embodiment of the present application, as shown in the drawings, Figure 3 The rotating shaft 222 is a lead screw, one end of the swing rod 224 is provided with a roller 226, the roller 226 is connected with the sliding block 223 through a spring 229, the grating seat 225 is provided with a grating 227, and the grating seat 225 is connected with the other end of the swing rod 224 through a grating shaft 228.

[0032] Specifically, in the present application, as a specific embodiment of the present application, the monochromator is an IV-type concave grating monochromator, and the dispersion spectrometer equation of the IV-type concave grating monochromator is:

[0033]

[0034] Wherein, m is the spectral order, σ is the grating constant, the grating rotation angle, δ is half of the grating beam deflection angle, l is the length of the swing rod, and x is the stroke of the swing rod end point.

[0035] By adding the interference assembly on the swing rod end point stroke mechanism, the swing rod end point stroke x is associated with the wavelength λ, and according to the Michelson monochromator distance change formula, it is:

[0036] x = Ak * l (Equation Two)

[0037] Wherein, x is the stroke of the end point of the connecting rod and the slider, l is the wavelength output by the monochromator, Ak is a constant, reflecting the relationship between x and l, and when x and l change proportionally, the interference image received by the detector remains unchanged. Equation Two is substituted into Equation One to obtain:

[0038]

[0039]

[0040] As can be seen from Equation Three, in an ideal state, Ak is a constant, which means that the interference fringes sensed by the detector do not change with the movement of the sinusoidal drive mechanism of the monochromator. In practice, since there is no ideal monochromator, Ak is not constant, and the change in interference fringes reflects the inherent error of the monochromator. According to the designed interference system, a quarter wavelength error generated by the sinusoidal drive mechanism of the monochromator is reflected in the light and dark changes of the interference fringes, and through the detector and computer analysis, the error of the sinusoidal drive mechanism of the monochromator can be accurately determined to one-tenth of the wavelength.

[0041] Further, in the present application, in order to ensure the clarity of the interference image, the interference assembly 30 can be further configured to include a compensation plate 34, the compensation plate 34 being arranged on the sinusoidal drive mechanism 22 and moving synchronously with the slider, the compensation plate 34 being arranged in parallel with the beam splitter 32, and the compensation plate 34 being used to improve the clarity of the interference image.

[0042] In this configuration, since the monochromatic light output by the monochromator has a certain spectral broadening, in order to ensure the clarity of the interference image, the use of a compensation plate with the same material and thickness as the beam splitter can solve the problem of spectral dispersion.

[0043] Further, in the present application, in order to be able to calibrate the entire wavelength band of the monochromator, a supercontinuum laser corresponding to the wavelength band and a corresponding wavelength detector can be selected according to the wavelength band used by the monochromator. Figure 2 If a suitable supercontinuum laser cannot be selected, as shown in FIG. 7, the monochromator wavelength error calibration device can be further configured to include a frequency doubling crystal 70, the frequency doubling crystal 70 being arranged between the supercontinuum laser 10 and the monochromator 20, and the frequency doubling crystal 70 being used to modulate the laser emitted by the supercontinuum laser 10 into laser with a set frequency and wavelength, and a corresponding optical path being selected.

[0044] In this configuration, by selecting a suitable supercontinuum laser and setting a frequency doubling crystal according to actual needs, the problem that only the peaks of spectral lines can be used to calibrate discrete points of the monochromator and the entire wavelength band cannot be calibrated in the prior art can be effectively solved.

[0045] Further, in the present application, in order to improve the laser transmission efficiency and ensure the laser transmission effect, the monochromator wavelength error calibration device further comprises a first optical fiber collimating lens 80, which is arranged between the supercontinuum laser 10 and the frequency doubling crystal 70, and is used for collimating the laser emitted by the supercontinuum laser 10.

[0046] In addition, in the present application, in order to further improve the laser transmission efficiency and ensure the laser transmission effect, the monochromator wavelength error calibration device can be configured to further comprise a first optical fiber converging lens 90, which is arranged between the frequency doubling crystal 70 and the monochromator 20, and is used for converging the laser output by the frequency doubling crystal 70.

[0047] In this way, the supercontinuum laser emits laser, the laser is collimated by the first optical fiber collimating lens 80 and then enters the frequency doubling crystal 70, the frequency doubling crystal 70 modulates the laser into laser with a set frequency and wavelength and then enters the first optical fiber converging lens 90, and the first optical fiber converging lens 90 converges the light and then sends it into the monochromator. This way can effectively reduce the loss of laser in the transmission process and greatly improve the laser transmission efficiency.

[0048] Further, in the present application, in order to improve the laser transmission efficiency and ensure the laser transmission effect, the monochromator wavelength error calibration device can be configured to further comprise a second optical fiber collimating lens 100, which is arranged between the first optical fiber converging lens 90 and the entrance slit of the monochromator 20, and is used for collimating the laser output by the first optical fiber converging lens 90.

[0049] In this way, before the laser output by the first optical fiber converging lens 90 enters the monochromator, the second optical fiber collimating lens 100 is used to collimate the laser, and then the collimated laser enters the monochromator through the entrance slit of the monochromator. This way can further improve the laser transmission efficiency and ensure the laser transmission effect.

[0050] In addition, in the present application, in order to further improve the laser transmission efficiency and ensure the laser transmission effect, the monochromator wavelength error calibration device can be configured to further comprise a second optical fiber converging lens 110, which is arranged between the exit slit of the monochromator 20 and the interference assembly 30, and is used for converging the monochromatic light output by the monochromator 20; and / or the monochromator wavelength error calibration device further comprises a third optical fiber collimating lens 120, which is arranged between the second optical fiber converging lens 110 and the interference assembly 30, and is used for collimating the monochromatic light output by the second optical fiber converging lens 110.

[0051] In this way, after the monochromator converts the laser into monochromatic light, the monochromatic light enters the second optical fiber converging lens 100 through the exit slit of the monochromator, the second optical fiber converging lens 100 converges the monochromatic light, and then the monochromatic light enters the third optical fiber collimating lens 120 for collimation, and the collimated monochromatic light enters the interference assembly. This way can further improve the laser transmission efficiency and ensure the laser transmission effect.

[0052] Further, in the present application, in order to improve the detection efficiency and imaging effect of the detector, the monochromator wavelength error calibration device can be further configured to include a lens 130. The interference assembly interferes with the monochromatic light output by the monochromator to generate interference fringes. The interference fringes are collected by the detector through the lens 130 and displayed on the imaging unit. Therefore, the detection efficiency and imaging effect of the detector can be improved. As a specific embodiment of the present application, the lens 130 includes a double convex lens or a single convex lens, which is not limited here and other types of lenses can also be selected.

[0053] According to another aspect of the present application, a monochromator wavelength error calibration method is provided, which includes: arranging an interference assembly 30 on a sinusoidal driving mechanism 22 of a monochromator 20; the interference assembly 30 interferes with monochromatic light output by the monochromator 20 to generate interference fringes; a detector 40 receives the interference fringes and displays the interference fringes on an imaging unit 50; and a control processor 60 drives the sinusoidal driving mechanism 22 of the monochromator 20 to move repeatedly and calibrates the wavelength error of the monochromator 20 according to the changes of the interference fringes on the imaging unit 50.

[0054] By applying this configuration, a monochromator wavelength error calibration method is provided. The error calibration method generates a laser beam with a set spectral range by an ultra-continuum spectrum laser, the laser beam enters a monochromator and outputs monochromatic light, an interference assembly interferes with the monochromatic light to generate interference fringes, a detector collects the interference fringes and displays them on an imaging unit, and a control processor drives the sinusoidal driving mechanism of the monochromator to move repeatedly and calibrates the wavelength error of the monochromator according to the changes of the interference fringes on the imaging unit. In this way, by arranging the interference assembly on the sinusoidal driving mechanism, the error of the sinusoidal driving mechanism of the monochromator in a quarter wavelength is reflected as the light and dark changes of the interference fringes according to the designed interference assembly. Through the analysis of the detector and the control processor, the error of the sinusoidal driving mechanism of the monochromator can be accurately determined to one-tenth of the wavelength. Therefore, compared with the prior art, the error calibration method provided by the present application greatly improves the calibration accuracy of the sinusoidal driving mechanism and effectively solves the technical problem of large wavelength calibration error of the monochromator.

[0055] In order to have a further understanding of the present application, the following will combine the specific embodiments of the present application with the accompanying drawings to make a detailed description. Figures 1 to 4The monochromator wavelength error calibration device and method provided by the present invention are described in detail.

[0056] like Figures 1 to 4 As shown, according to a specific embodiment of the present invention, a monochromator wavelength error calibration device is provided. The type IV concave grating monochromator wavelength error calibration device includes a supercontinuum laser 10, a monochromator 20, an interference assembly 30, a detector 40, an imaging unit 50, a control processor 60, a frequency doubling crystal 70, a first fiber collimating lens 80, a first fiber converging lens 90, a second fiber collimating lens 100, a second fiber converging lens 110, a third fiber collimating lens 120, and a lens 130. The type IV concave grating monochromator wavelength error calibration method specifically includes the following steps.

[0057] First, according to the operating band of the IV type concave grating monochromator, select the corresponding supercontinuum laser 10 and the detector 40 of the corresponding band. If the supercontinuum laser 10 of the appropriate band cannot be selected, a frequency doubling crystal 70 can be used to modulate the laser frequency and the corresponding optical path can be selected.

[0058] Second, turn on the supercontinuum laser, wait for the supercontinuum laser 10 to stabilize, adjust the monochromator 20 to the calibration state, adjust the monochromator entrance slit 21a and the monochromator exit slit 21b to the corresponding widths, align the second fiber collimating lens 100 with the entrance slit 21a of the monochromator, and align the second fiber converging lens 110 with the exit slit 21b of the monochromator.

[0059] Third, fix the beam splitter 32 and the reference retroreflector 31 to fixed positions near the motor of the monochromator drive mechanism, and fix the compensation plate 16 and the target retroreflector 33 to the slider of the monochromator drive mechanism, corresponding to the positions as shown in FIG. Figure 3 The interference pattern formed by the interference assembly reflects changes in the movement of the sinusoidal mechanism. According to the designed interference system, an error of a quarter wavelength in the positive selection drive mechanism of the monochromator is reflected as a change in the brightness of the interference fringes. Through detectors and computer analysis, the error of the monochromator's positive selection drive mechanism can be accurately determined to one tenth of the wavelength.

[0060] Fourth, the third fiber collimating lens 120, the lens 130 and the detector 40 of the corresponding wavelength band are adjusted so that the detector 40 of the corresponding wavelength band can receive the interference fringes.

[0061] Fifth, after the monochromator wavelength error calibration device is adjusted, the supercontinuum laser 10 generates a laser beam with a wide spectral range, and the supercontinuum laser 10 is a typical supercontinuum laser. The energy and wavelength of the supercontinuum laser are not limited, and a supercontinuum laser with a wavelength of 1000 nm to 3000 nm is preferred. If a suitable supercontinuum laser 10 cannot be selected, a frequency-doubling crystal 70 can be used to modulate the laser frequency, which is conducted into the frequency-doubling crystal 70 through an optical fiber and a first optical fiber collimation lens 80 to adjust the frequency of the laser to meet the working wavelength range of the monochromator, and then introduced into an optical fiber through a first optical fiber converging lens 90 to obtain a light source with a corresponding wavelength.

[0062] Sixth, the second optical fiber collimation lens 100 collimates the wide-spectrum laser and introduces it into the monochromator 20. The monochromatic light after being split by the monochromator is collected by the second optical fiber converging lens 110, and then introduced into the interference assembly 30 through an optical fiber and a third optical fiber collimation lens 120. The interference fringes are received by the corresponding wavelength detector 40.

[0063] Seventh, the control processor 60 drives the monochromator 20 to move repeatedly, and records the changes of the interference fringes at different positions. The changes of the interference fringes reflect the error of the sine value of the sine mechanism of the monochromator. The monochromator is calibrated according to the change information of the interference fringes. In this embodiment, the control processor 60 is a computer.

[0064] In summary, the present application provides a monochromator wavelength error calibration device and method. The error calibration device sets an interference assembly on the sine driving mechanism. According to the designed interference assembly, the error of one-quarter wavelength of the sine driving mechanism of the monochromator is reflected as the changes of the brightness of the interference fringes. Through the analysis of the detector and the control processor, the error of the sine driving mechanism of the monochromator can be accurately determined to one-tenth of the wavelength. Therefore, compared with the prior art, the error calibration method provided by the present application greatly improves the calibration accuracy of the sine driving mechanism, can realize the calibration of the entire wavelength range, and effectively solves the technical problems that the wavelength calibration error of the monochromator is large, and only the peaks of the spectral line lamp can be used to calibrate the monochromator at discrete points, and the entire wavelength range cannot be calibrated.

[0065] For purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "rear", "front", "vertical", "horizontal", and derivatives thereof shall relate to the application as oriented in the drawing. The terms "attached", "connected" and "coupled" as used herein refer to the connection between two members, directly or indirectly. Such connection can be manifested in various ways, for example and without limitation, through mechanical, electrical, and / or magnetic means. Such connection can occur at a single location or at multiple locations among two members, and can occur locally or remotely via an electrical signal travelling along a wire or network. Such connection can be temporary or permanent, and can or can not be made under the auspices of a specific program or application. Such connection can be direct or indirect, and such connection can occur through one or more other members.

[0066] In addition, it should be pointed out that the use of "first", "second" and the like words to qualify parts, is only intended to facilitate the distinction of the corresponding parts, and such words do not have a special meaning unless otherwise stated, and therefore cannot be understood as limiting the scope of protection of the present application.

[0067] The preferred embodiments of the present application are described above in detail. The present application, however, is not limited to the precise embodiments described. Instead, various changes and modifications can be suggested to one skilled in the art. It is intended to encompass those changes and modifications insofar as they fall within the scope of the present application.

Claims

1. A monochromator wavelength error calibration device, characterized in that: The monochromator wavelength error calibration device comprises: Supercontinuum lasers (10); a monochromator (20), the monochromator (20) being connected to the supercontinuum laser (10); an interference component (30), the interference component (30) being arranged on the sinusoidal drive mechanism of the monochromator (20), and the interference component (30) being used to interfere with the monochromatic light output by the monochromator (20) to generate interference fringes; A detector (40) and an imaging unit (50), wherein the detector (40) is used to collect the interference fringes and display them on the imaging unit (50); A control processor (60) is connected to the monochromator (20), and the control processor (60) is used to drive the sinusoidal drive mechanism of the monochromator (20) to move repeatedly and calibrate the wavelength error of the monochromator (20) according to the change of the interference fringes on the imaging unit (50).

2. The monochromator wavelength error calibration device according to claim 1, characterized in that: The interference assembly (30) includes a reference corner conical reflector (31), a spectroscope (32) and a target corner conical reflector (33); the monochromator (20) includes a monochromator body (21) and the sinusoidal drive mechanism (22); the reference corner conical reflector (31) and the spectroscope (32) are arranged on the monochromator body (21); the target corner conical reflector (33) is arranged on the sinusoidal drive mechanism (22); and the sinusoidal drive mechanism (22) is used to drive the target corner conical reflector (33) to move.

3. The monochromator wavelength error calibration device according to claim 2, characterized in that: The interference assembly (30) further includes a compensation plate (34), the compensation plate (34) being arranged on the sinusoidal drive mechanism (22), the compensation plate (34) being arranged parallel to the spectroscope (32), and the compensation plate (34) being used to improve the clarity of the interference image.

4. The monochromator wavelength error calibration device according to any one of claims 1 to 3, characterized in that: The monochromator wavelength error calibration device further comprises a frequency doubling crystal (70), wherein the frequency doubling crystal (70) is arranged between the supercontinuum laser (10) and the monochromator (20), and the frequency doubling crystal (70) is used to modulate the laser light emitted by the supercontinuum laser (10) into laser light of a set frequency and wavelength.

5. The monochromator wavelength error calibration device according to claim 4, characterized in that: The monochromator wavelength error calibration device further comprises a first optical fiber collimating lens (80), wherein the first optical fiber collimating lens (80) is arranged between the supercontinuum laser (10) and the frequency doubling crystal (70), and the first optical fiber collimating lens (80) is used to collimate the laser light emitted by the supercontinuum laser (10).

6. The monochromator wavelength error calibration device according to claim 5, characterized in that: The monochromator wavelength error calibration device further comprises a first optical fiber converging lens (90), the first optical fiber converging lens (90) being arranged between the frequency doubling crystal (70) and the monochromator (20), and the first optical fiber converging lens (90) being used to converge the laser light output by the frequency doubling crystal (70).

7. The monochromator wavelength error calibration device according to claim 6, characterized in that: The monochromator wavelength error calibration device further comprises a second optical fiber collimating lens (100), wherein the second optical fiber collimating lens (100) is arranged between the first optical fiber converging lens (90) and the incident slit of the monochromator (20), and the second optical fiber collimating lens (100) is used to collimate the laser output by the first optical fiber converging lens (90).

8. The monochromator wavelength error calibration device according to any one of claims 1 to 3, characterized in that: The monochromator wavelength error calibration device further comprises a second optical fiber converging lens (110), the second optical fiber converging lens (110) being arranged between the exit slit of the monochromator (20) and the interference assembly (30), and the second optical fiber converging lens (110) being used to converge the monochromatic light output by the monochromator (20); and / or the monochromator wavelength error calibration device further comprises a third optical fiber collimating lens (120), the third optical fiber collimating lens (120) being arranged between the second optical fiber converging lens (110) and the interference assembly (30), and the third optical fiber collimating lens (120) being used to collimate the monochromatic light output by the second optical fiber converging lens (110).

9. The monochromator wavelength error calibration device according to claim 2, characterized in that: The sinusoidal drive mechanism (22) comprises a motor (221), a rotating shaft (222), a slider (223), a rocker (224) and a grating seat (225), wherein the motor (221) is used to drive the rotating shaft (222) to rotate, the slider (223) is threadedly connected to the rotating shaft (222), and the rotating shaft (222) can drive the slider (223) to move in a straight line direction, one end of the rocker (224) is matched with the slider (223), and the slider (223) can drive the rocker (224) to swing, and the other end of the rocker (224) is connected to the grating seat (225), and the grating seat (225) is rotatably arranged on the monochromator body (21).

10. A monochromator wavelength error calibration method, characterized in that: The monochromator wavelength error calibration method comprises: The interference assembly (30) is arranged on the sinusoidal drive mechanism (22) of the monochromator (20); The interference component (30) interferes with the monochromatic light output by the monochromator (20) to generate interference fringes; The detector (40) receives the interference fringes and displays the interference fringes on an imaging unit (50); The control processor (60) drives the sinusoidal drive mechanism (22) of the monochromator (20) to move repeatedly and calibrates the wavelength error of the monochromator (20) according to the change of the interference fringes on the imaging unit (50).

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