CN103185640A - Michelson interferometer control device and control method - Google Patents
Michelson interferometer control device and control method Download PDFInfo
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- CN103185640A CN103185640A CN2012105426459A CN201210542645A CN103185640A CN 103185640 A CN103185640 A CN 103185640A CN 2012105426459 A CN2012105426459 A CN 2012105426459A CN 201210542645 A CN201210542645 A CN 201210542645A CN 103185640 A CN103185640 A CN 103185640A
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Abstract
The invention discloses a Michelson interferometer control device and control method. A Michelson interferometer is arranged on a rack and comprises a photoelectric sensor circuit, a controller, a motor, a display, a copper piece arranged on a drum of the Michelson interferometer and a drum momentum detection circuit which is arranged on the rack close to the drum and is corresponding to the copper piece; the Michelson interferometer control device is respectively electrically connected with the photoelectric sensor circuit, the drum momentum detection circuit, the motor and the display; the motor is connected with the drum, and the photoelectric sensor circuit is arranged on the rack of an observation screen close to the Michelson interferometer; and the motor is a direct current speed reduction motor. The Michelson interferometer control device and control method disclosed by the invention have the characteristics that wavelength measurement accuracy of light wave is effectively improved, labour intensity of a measurer is reduced, measuring efficiency is improved, structure is simple, operation is easy and a measuring result can be visually displayed.
Description
Technical field
The present invention relates to a kind of opertaing device of measurement mechanism, especially relate to a kind of Michelson interferometer control device and control method that can effectively improve the optical wavelength measuring accuracy and measure efficient.
Background technology
Michelson interferometer is generally used for measurement of doing optical wavelength, refractive index, thickness and concentric circles interference fringe etc.
When using the michelson interferometer measurement interference fringe, need count hundreds of the interference fringes of passing the visual field.Traditional method is by hundreds of interference fringes of artificial calculating, the shortcoming of this method of counting: (1) eye fatigue.(2) degree of stability not high (interference fringe has some to rock slightly, just can't count).(3) make mistakes easily.In order to have improved the accuracy of measuring, take the method repeatedly measured usually, but this method is difficult to improve the precision of measuring.
For this reason, domestic and international many scholar's research designs are the various devices of counting automatically, for example people such as the Zhang Xuelong of China Mining University once designed with counter and realized the device of counting automatically, its cardinal principle is by photoelectric switching circuit light signal to be converted to simulating signal to arrive digital signal again, in the final signal feed-in counter.But the defective of this system is a little less than the antijamming capability, in case extraneous generation disturbance causes the visual field interference fringe to be rocked, can influence the accuracy of counting.
At the deficiency of said method, this paper is according to series materials such as single-chip microcomputer and data acquisitions, introduces a kind of online Michelson interferometer system, and it is to programme by single-chip microcomputer language and other higher level lanquages to realize the communication of computing machine and single-chip microcomputer.Carry out mechanical mechanism by single-chip microcomputer by reducing motor, finish the rotation of advance and retreat knob, reach the manual operations that replaces the people.Come the number of variation of the light and shade line of detection laser interference fringe by light activated element, and pass computing machine back by single-chip microcomputer and show that in addition, a burst wheel number of turns also reaches single-chip microcomputer by photoelectric sensor circuit and delivers to computing machine and shows.And computing machine also can be controlled single-chip microcomputer, realizes bi-directional communication function.Having avoided in whole measuring process because stochastic error artificial and that extraneous factor causes, and can draw precise results at short notice, is a kind of conveniently survey instrument.Also can be used for demonstrating the measurement of measuring wavelength.
Chinese patent mandate publication number CN101520439A, authorize and disclose a kind of Defectoscope control device open day on September 2nd, 2009, mainly by Y shape support, reach the control roll formation that is connected Y shape support front end by screw, its innovative point is: described control roll two ends are connected with miniature bearing respectively, described miniature bearing is embedded in the dead eye of the outer terminal screw of support, in order to make control roll and support coaxial connection of energy, screw divides inner layer surface and outer layer surface, described outer layer surface is A, B, three layers of disk stairstepping of C, inner layer surface is that the embedded hole of fabrication hole and bearing constitutes, and the embedded hole of described fabrication hole and bearing communicates.This invention is a kind of control device of defectoscope, has the coaxial and concentricity that has guaranteed control roll, has improved the accuracy of detection to steel ball, and described slippage prevention device greatly reduces the probability that occurs skidding in the control lever flaw detection process, guarantees to detect the stable of effect.
Summary of the invention
The present invention is in order to overcome the deficiency that people of the prior art read number of interference fringes, a kind of Michelson interferometer control device and control method that can effectively improve the optical wavelength measuring accuracy and measure efficient to be provided.
To achieve these goals, the present invention is by the following technical solutions:
A kind of Michelson interferometer control device, described Michelson interferometer is located on the frame, comprises photoelectric sensor circuit, controller, motor, display, is located at copper sheet on the drum of Michelson interferometer, is arranged near the drum amount of spin testing circuit corresponding with copper sheet on the frame of drum; Described controller is electrically connected with photoelectric sensor circuit, drum amount of spin testing circuit, motor and display respectively; Motor is connected with drum, and described photoelectric sensor circuit is located on the frame near the observation screen of Michelson interferometer; Described motor is DC speed-reducing.
Michelson interferometer control device of the present invention drives the rotating operation of drum by reducing motor, has replaced people's manual operations.Responded to the variation of the light and shade line of laser interferencefringes by the light activated element of photoelectric sensor circuit, and by the calculating of the software in controller number of interference fringes, and detect the number of turns that drum rotates by drum amount of spin testing circuit, and by the calculating of the software in controller drum amount of spin, controller calculates optical wavelength according to number of interference fringes and drum amount of spin, and in display number of interference fringes, drum amount of spin and optical wavelength is shown.
Avoid stochastic error artificial and that extraneous factor causes in the measuring process, and can draw accurate measurement result at short notice, improved measurement efficient.
Michelson interferometer control device of the present invention has been realized the automatic calculating of interference fringe and drum amount of spin, has not only alleviated gauger's burden greatly, and has improved the degree of accuracy of measurement data, has improved work efficiency; And it is easy to operate, simple and practical.
As preferably, described photoelectric sensor circuit comprises optical detection circuit, amplifying circuit and the shaping circuit that connects successively; Described optical detection circuit comprises photoresistance, operational amplifier and several resistance.
As preferably, described drum amount of spin testing circuit comprises copper sheet sensor circuit and oscillating circuit; The copper sheet sensor circuit comprises triode, reflective photoelectric switch, several resistance and several electric capacity.
Design is during oscillatory circuit, makes the bandwidth of oscillatory circuit comprise the frequency of the interference fringe that light wave inspires of common detection.
As preferably, also comprise the camera of being located on the frame, described camera is electrically connected with controller.
A kind of control method of Michelson interferometer control device comprises the steps:
(5-1) the interference fringe sum M that needs detection is set in controller in advance; Open the power supply of controller, controller control motor, display, drum amount of spin testing circuit and photoelectric sensor circuit are started working;
(5-2) light-wave irradiation is to Michelson interferometer, and controller control driven by motor drum rotates, and photoelectric sensor circuit detects lightwave signal and detected signal is input in the controller, and controller calculates number of interference fringes N; Drum amount of spin testing circuit is with in the drum signal input controller that detects, and controller calculates drum and rotates number of turns △ d; When N＞M, controller stops the counting that number of interference fringes and drum rotate the number of turns;
(5-3) controller utilizes formula
Calculate optical wavelength λ, and demonstration number of interference fringes N, drum rotate number of turns △ d and optical wavelength λ in display; Controller control motor, drum amount of spin testing circuit and photoelectric sensor circuit quit work.
As preferably, described photoelectric sensor circuit detects lightwave signal and detected signal is input in the controller, and controller calculates number of interference fringes N; Also comprise the steps:
(6-1) photoresistance of optical detection circuit accept illumination penetrate the back resistance change, electric signal in the optical detection circuit changes, amplifying circuit amplifies the electric signal of optical detection circuit output, and the electric signal that shaping circuit is exported amplifying circuit converts pulse signal to and imports in the controller;
After (6-2) controller receives pulse signal, postpone several burst lengths, begin to calculate pulse number, obtain number of interference fringes.
When the drum on the driven by motor Michelson interferometer rotates, have light and dark interference fringe constantly " emerging " or " flooding " on the observation screen.Certain any light intensity also is that light and shade alternately changes on the interference fringe, and its light and shade changes one-period, once the handling up of lucky corresponding interference fringe.When light intensity, pulse of sensor electrical road direction controller input.Therefore, photoelectric sensor circuit changes the pulse signal that has converted to for the recording interference fringe number with the light intensity of certain point on the observation screen.
As preferably, described drum amount of spin testing circuit is with in the drum signal input controller that detects, and controller calculates drum amount of spin △ d; Comprise the steps:
When copper sheet passes through, low level of drum amount of spin testing circuit output, when controller received low level and N=1, controller began to calculate the drum amount of spin, and a low level tail-pulley of every reception amount of spin count value increases by 1.
Oscillatory circuit is given reference frequency of drum amount of spin testing circuit, and when in the bandwidth range of interference fringe frequency at oscillatory circuit that the detected light wave of reflective photoelectric switch excites, drum amount of spin testing circuit is to low level of controller input.
When the reflective photoelectric switch inspection did not detect light wave, drum amount of spin testing circuit kept high level to the signal of controller input.
As preferably, also comprise the camera of being located on the frame, described camera is electrically connected with controller; It is characterized in that, also comprise the steps:
When first time when interference fringe counting and last interference fringe counting, controller is controlled the photo that camera is taken drum respectively, and with the photo storage of taking to the hard disk of controller; Interference fringe counting shows two photos after finishing in display screen.
The drum number of turns when drum number of turns deducts interference fringe counting for the first time when utilizing last interference fringe counting can obtain accurate drum amount of spin.
Observe two photos that show on the display screen, obtain to be accurate to the drum amount of spin of decimal, adopt this drum amount of spin to calculate optical wavelength and can obtain accurate more optical wavelength.
And, camera be arranged so that Michelson interferometer control device of the present invention can make the gauger see for the first time interference fringe counting and last interference fringe counting more intuitively the time drum amount of spin difference, can give the more intuitive impression of gauger.
Therefore, the present invention has following beneficial effect: (1) effectively improves the optical wavelength measuring accuracy; (2) reduction gauger's labour intensity improves and measures efficient; (3) simple in structure, easy to operate; (4) measurement result can intuitively show.
Description of drawings
Fig. 1 is a kind of theory diagram of the present invention;
Fig. 2 is a kind of process flow diagram of embodiments of the invention 1;
Fig. 3 is a kind of process flow diagram of embodiments of the invention 2.
Among the figure: electric transducer circuit 1, controller 2, motor 3, display 4, drum amount of spin testing circuit 5, camera 6.
Embodiment
The present invention will be further described below in conjunction with the drawings and specific embodiments.
Embodiment 1
Embodiment as shown in Figure 1 is a kind of Michelson interferometer control device, described Michelson interferometer is located on the frame, comprises photoelectric sensor circuit 1, controller 2, motor 3, display 4, is located at copper sheet on the drum of Michelson interferometer, is arranged near the drum amount of spin testing circuit 5 corresponding with copper sheet on the frame of drum; Controller is electrically connected with photoelectric sensor circuit, drum amount of spin testing circuit, motor and display respectively; Motor is connected with drum, and photoelectric sensor circuit is located on the frame near the observation screen of Michelson interferometer; Described motor is DC speed-reducing.Photoelectric sensor circuit comprises optical detection circuit, amplifying circuit and the shaping circuit that connects successively; Described optical detection circuit comprises photoresistance, operational amplifier and 3 resistance.
Drum amount of spin testing circuit comprises copper sheet sensor circuit and oscillating circuit; The copper sheet sensor circuit comprises triode, reflective photoelectric switch, 4 resistance and 2 electric capacity.Also comprise the camera of being located on the frame 6, camera is electrically connected with controller.
As shown in Figure 2, a kind of control method of Michelson interferometer control device comprises the steps:
When copper sheet passed through, when controller received low level and N=1, controller began to calculate the drum amount of spin, and a low level tail-pulley of every reception amount of spin count value increases by 1, thereby obtains drum amount of spin △ d.
As N during greater than 900, controller stops the counting of number of interference fringes and drum amount of spin; During last interference fringe counting, controller control camera is taken the photo of drum, and with the photo storage of taking to the hard disk of controller;
Embodiment 2
Comprise structure divisions all among the embodiment 1 and step part among the embodiment 2; And comprise the steps:
As shown in Figure 3, step 500, the drum number of turns on two photos on the manual observation reading displayed screen, the drum number of turns on two photos is respectively 1.5 circles and 7.6 and encloses, and then manually calculates △ d=7.6-1.5=6.1; With N=900, △ d=6.1 substitution formula
In, obtain λ=1.36 * 10
7Nanometer; So far obtain the more accurate wavelength of measured light wave.
Should be understood that present embodiment only to be used for explanation the present invention and be not used in and limit the scope of the invention.Should be understood that in addition those skilled in the art can make various changes or modifications the present invention after the content of having read the present invention's instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.
Claims (8)
1. Michelson interferometer control device, described Michelson interferometer is located on the frame, it is characterized in that, comprise photoelectric sensor circuit (1), controller (2), motor (3), display (4), be located at copper sheet on the drum of Michelson interferometer, be arranged near the drum amount of spin testing circuit (5) corresponding with copper sheet on the frame of drum; Described controller is electrically connected with photoelectric sensor circuit, drum amount of spin testing circuit, motor and display respectively; Motor is connected with drum, and described photoelectric sensor circuit is located on the frame near the observation screen of Michelson interferometer; Described motor is DC speed-reducing.
2. Michelson interferometer control device according to claim 1 is characterized in that, described photoelectric sensor circuit comprises optical detection circuit, amplifying circuit and the shaping circuit that connects successively; Described optical detection circuit comprises photoresistance, operational amplifier and several resistance.
3. Michelson interferometer control device according to claim 1 is characterized in that, described drum amount of spin testing circuit comprises copper sheet sensor circuit and oscillating circuit; The copper sheet sensor circuit comprises triode, reflective photoelectric switch, several resistance and several electric capacity.
4. according to claim 1 or 2 or 3 described Michelson interferometer control device, it is characterized in that also comprise the camera of being located on the frame (6), described camera is electrically connected with controller.
5. the control method of a Michelson interferometer control device according to claim 1 is characterized in that, comprises the steps:
(5-1) the interference fringe sum M that needs detection is set in controller in advance; Controller control motor, display, drum amount of spin testing circuit and photoelectric sensor circuit are started working;
(5-2) light-wave irradiation is to Michelson interferometer, and controller control driven by motor drum rotates, and photoelectric sensor circuit detects lightwave signal and detected signal is input in the controller, and controller calculates number of interference fringes N; Drum amount of spin testing circuit is with in the drum signal input controller that detects, and controller calculates drum amount of spin △ d; When N＞M, controller stops the counting of number of interference fringes and drum amount of spin;
(5-3) controller utilizes formula
Calculate optical wavelength λ, and in display, show number of interference fringes N, drum amount of spin △ d and optical wavelength λ; Controller control motor, drum amount of spin testing circuit and photoelectric sensor circuit quit work.
6. the control method of Michelson interferometer control device according to claim 5 is characterized in that, described photoelectric sensor circuit detects lightwave signal and detected signal is input in the controller, and controller calculates number of interference fringes N; Also comprise the steps:
(6-1) photoresistance of optical detection circuit accept illumination penetrate the back resistance change, electric signal in the optical detection circuit changes, amplifying circuit amplifies the electric signal of optical detection circuit output, and the electric signal that shaping circuit is exported amplifying circuit converts pulse signal to and imports in the controller;
After (6-2) controller receives pulse signal, postpone several burst lengths, begin to calculate pulse number, obtain number of interference fringes.
7. the control method of Michelson interferometer control device according to claim 5 is characterized in that, described drum amount of spin testing circuit is with in the drum signal input controller that detects, and controller calculates drum amount of spin △ d; Comprise the steps:
When copper sheet passes through, low level of drum amount of spin testing circuit output, when controller received low level and N=1, controller began to calculate the drum amount of spin, and a low level tail-pulley of every reception amount of spin count value increases by 1.
8. the control method of Michelson interferometer control device according to claim 5 also comprises the camera of being located on the frame, and described camera is electrically connected with controller; It is characterized in that, also comprise the steps:
When first time when interference fringe counting and last interference fringe counting, controller is controlled the photo that camera is taken drum respectively, and with the photo storage of taking to the hard disk of controller; Interference fringe counting shows two photos after finishing in display screen.
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| CN201210542645.9A CN103185640B (en) | 2012-12-13 | 2012-12-13 | Michelson interferometer control device and control method |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104848946A (en) * | 2015-04-17 | 2015-08-19 | 南京邮电大学 | WIFI-based Michelson interferometer automatic detection device |
| CN105241557A (en) * | 2015-10-15 | 2016-01-13 | 南阳理工学院 | Novel Michelson interference fringe measurement and control apparatus and application method thereof |
| CN105606231A (en) * | 2016-02-01 | 2016-05-25 | 黎碧莲 | Digital display type Michelson interferometer automatic measurement system and method |
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| CN103185640B (en) | 2014-12-03 |
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