CN108844488A - Annular polishing pitch panel surface face shape on-line monitoring device and monitoring method - Google Patents

Abstract

Panel surface face shape on-line monitoring device and monitoring method are polished in a kind of annular polishing, device includes the fixed bracket of system, reflecting mirror, reflector alignment mirror holder, lens, spectroscope, CCD, lens barrel adjustment device, can be manually rotated platform, light-conductive optic fibre and light source, the face shape of the pitch disk in polishing process can be monitored online in apparatus of the present invention, it can make the face shape stable convergence of disk, have the characteristics that measurement accuracy is high, structure is simple, real-time is good, improves the processing efficiency of optical element.

Description

On-line monitoring device and monitoring method for surface shape of annular polished asphalt disc

technical field

The invention relates to an annular polishing machine, in particular to an on-line monitoring device and a monitoring method for the surface shape of an asphalt disk polished by an annular polishing machine.

Background technique

Annular polishing is a key process for processing high-precision planar optical components. This processing technology is the main means to obtain high-precision planar optical components. The processing results directly determine the final quality of optical components. For a long time, the polishing process has always been the bottleneck in the processing process of high-precision planar optical components, and its manufacturing cost and man-hours account for more than half of the entire manufacturing process.

Ring polishing is to adjust the surface shape of the workpiece by controlling the surface shape of the polishing disc. The polishing disc (the main component is a mixture of asphalt and rosin) is a viscoelastic material, and its surface shape can change the pressure on the surface of the polishing disc by changing the position of the correction disc. The distribution is adjusted. Because ring polishing is affected by various factors such as temperature, humidity, and the hardness of the disk surface, coupled with the lack of sufficient theoretical research, this adjustment process is very difficult. The current ring polishing process still largely depends on the experience of workers, and stays on a qualitative rather than quantitative basis, which seriously restricts the processing efficiency of optical components.

In actual processing, in order to understand the change of the surface shape of the polishing disc during the processing, it is necessary to frequently remove the workpiece from the polishing disc and then use the interferometer to detect it. According to the test results, new processing parameters are set for processing until the surface shape meets the requirements, which generally requires multiple repetitions. After the workpiece and the calibration disc are separated from the polishing disc, they need to be kept at a constant temperature for 1-2 hours before they can be tested. During this time, the upper and lower polishing discs of the calibration disc will cause new uncertain effects on the polishing disc.

Contents of the invention

The object of the present invention is to provide an on-line monitoring device for surface shape of asphalt discs polished by a ring polisher in order to solve the above-mentioned problems in the prior art.

Technical solution of the present invention is as follows:

The on-line monitoring device for the surface shape of the polishing disk is characterized in that the device includes a system fixing bracket, a manual rotary table fixed on the bracket, a pitch adjustment mechanism, an integrated packaged CCD, a beam splitter, and a collimating lens fixed on the pitch adjustment Mechanismally, the imaging surface of the CCD is located on the focal plane of the collimating lens, the integrated packaging system is connected to the light source through the light-guiding optical fiber, and the CCD is connected to the computer through the data line; the reflector with the two-dimensional adjustment frame It is rigidly connected with the correction plate through a connecting piece. The light emitted by the light source passes through the light-guiding fiber, passes through the beam splitter and collimating lens, and the light reflected by the reflector passes through the lens and beam splitter and forms an image on the CCD, and transmits the data collected by the CCD to the computer through the data line.

The left side of the manual rotating table is fixedly connected to the fixed bracket, and the right side is fixedly connected to the pitch adjustment mechanism. The left and right parts can be rotated and fixed around the central axis in a plane perpendicular to the paper surface.

The lower end of the pitch adjustment mechanism is provided with a knob, and the device adjusts the pitch angle of the system by adjusting the knob at the lower end.

The reflective surface coating of the reflector with the two-dimensional adjustment frame can adjust the spatial attitude of the reflector by adjusting the knob at the lower end of the two-dimensional adjustment frame.

In the process of circular polishing, the polishing disc always tends to a flat or spherical surface naturally. At this time, the correction disc and the reflector form an angle α with the horizontal direction. The collimating lens becomes a parallel beam; the parallel beam is reflected by a mirror with a certain inclination, and after being converged by the collimating lens and the beam splitter again, it is converged on the CCD, and the position of the formed image changes and is input to the A computer, which calculates the value of the angle through real-time software, and stores it.

According to the geometric relationship in Figure 2, it can be seen that the relationship between the PV value △h of the surface shape of the workpiece, the diameter D of the workpiece, the inclination angle α of the correction disc, and the eccentric distance e of the correction disc is:

The computer can detect the inclination angle α in real time, thereby detecting the surface shape of the polishing disc in real time.

In the actual processing process, due to the existence of various external interference signals, the very small angle signal will be submerged in the noise signal. After the angle signal collected by the computer is processed by low-pass filtering, the effective angle change signal is extracted, and then Combined with specific processing parameters, the surface shape information of the polishing disc can be calculated.

Technical effect of the present invention is as follows:

1. The on-line monitoring device for polishing the asphalt disk surface shape of the annular polishing machine of the present invention has a simple structure and high measurement accuracy, which greatly reduces the labor intensity of the operator and improves the processing efficiency;

2. The measuring device of the present invention has no contact with the surface of the polishing disc, and has no interference with the processing process. The measurement accuracy of the surface shape of the monitoring workpiece with a measuring diameter of 100mm is less than 0.1λ;

3. After the online real-time monitoring results are processed by the computer, the processing parameters can be changed in time, so that the surface shape of the polishing disc can be stabilized and converged to the required surface shape.

Description of drawings

Fig. 1 is the structural representation of the on-line monitoring device for the surface shape of the asphalt disk polished by the ring polishing machine of the present invention;

Fig. 2 is the sectional schematic view of the polishing workpiece of the annular polishing machine;

Fig. 3 is the optical path diagram of the horizontal inclination measurement of the correction disc;

Fig. 4 Comparison results of real-time online detection and offline detection;

In the figure, 1 is the system fixing bracket, 2 is the manual rotating table, 3 is the pitch adjustment mechanism, 4 is the hinge, 5 is the correction disk, 6 is the CCD, 7 is the beam splitter, 8 is the collimating lens, 9 is the 10 is the connector of the correction plate and the reflector, 11 is the marble turntable, 12 is the light guide fiber, 13 is the optical element, 14 is the ring polished asphalt disc, 15 is the computer, and 16 is the light source.

Detailed ways

The present invention will be further described below in conjunction with the embodiments and accompanying drawings, but the protection scope of the present invention should not be limited thereby.

Referring to Fig. 1, Fig. 1 is the structural schematic diagram of the on-line monitoring device of the polished asphalt disc surface of the present invention, as can be seen from the figure, the on-line monitoring device of the polishing disc surface of the present invention, the device comprises a fixed support 1, a manual rotary table 2. Pitch adjustment mechanism 3, hinge 4, correction disc 5, CCD6, beam splitter 7, collimator lens 8, the CCD6, beam splitter 7 and collimator lens 8 are integrated and packaged and fixed on the pitch adjustment mechanism 3 Above, the left side of the manual rotary table 2 is fixedly connected to the fixed bracket 1, and the right side is fixedly connected to the pitch adjustment mechanism 3. The in-plane rotation of the surface is adjusted and locked; the imaging surface of the CCD6 is located on the focal plane of the collimator lens 8, and the integrated packaging system is connected with the light source 16 through the light-guiding optical fiber 12, and the CCD6 passes through The data line is connected with the computer 15; the reflector 9 with the two-dimensional adjustment frame is rigidly connected with the correction disc 5 through the connector 10, and the reflection surface of the reflector 9 is parallel to the lower surface of the correction disc 5, reflecting The reflective surface of the mirror 9 is coated, and the surface PV value is less than 0.1λ (λ=632.8nm). The light emitted by the light source 16 passes through the light-guiding optical fiber 12 and passes through the beam splitter 7 and the collimating lens 8 Then irradiate the reflector 9, and the light reflected by the reflector 9 is imaged on the CCD6 after passing through the lens 8 and the beam splitter 7.

When in use, the machine tool is at first shut down, and the manual rotary table 2, the pitch adjustment mechanism 3 and the reflector 9 with the two-dimensional adjustment frame are adjusted in cooperation, so that a clear crosshair image appears on the CCD6. Turn the correction disc 5 manually to keep the position of the crosshairs unchanged. Referring to Fig. 3, the light emitted by the light source 16 is transmitted through the light-guiding optical fiber 12, split by the beam splitter 7, and then becomes a parallel beam through the collimator lens 8; The position of the image formed by the straight lens 8 and the beam splitter 7 converging on the CCD changes and is input into the computer 15, which calculates the value of the angle through real-time software and stores it. Turn on the machine tool, and adjust the rotational speeds of the annular polishing asphalt disk 14 and the correction disk 5 to appropriate values. Set the reference plane and continuous sampling time interval on the computer in sequence, and then let the computer carry out continuous data collection, and the computer will process the real-time data collected by the program to obtain the real-time change law of the surface shape of the optical element, see Figure 4 (Fig. In λ=632.8nm), it is a comparison image of a continuous online detection and an off-line interferometer detection result. Experimental results show that the invention realizes the on-line detection of the surface shape of the asphalt disk, and greatly shortens the processing period of the optical element.

Claims (3)

1. a kind of polishing panel surface face shape on-line monitoring device, it is characterised in that the device includes fixed bracket (1), can be manually rotated Platform (2), pitching adjusting mechanism (3), hinge (4), correction disk (5), CCD (6), spectroscope (7), collimation lens (8), it is described It is fixed on after CCD (6), spectroscope (7) and collimation lens (8) integration packaging on the pitching adjusting mechanism (3), the hand The left side of dynamic turntable (2) is fixedly connected with the fixation bracket (1), and right side and the pitching adjusting mechanism (3) are fixed Connection, the left and right sides can adjust and lock in the plane internal rotation of vertical paper around manual turntable (2) central axis；Described The imaging surface of CCD (6) is located on the focal plane of the collimation lens (8), and the integration packaging system passes through light-conductive optic fibre (12) it is connected with light source (16), the CCD (6) is connected by data line with computer (15)；With the anti-of two-dimension adjustment frame It penetrates mirror (9) and correction disk (5) is rigidly connected by connector (10), the reflecting surface of the reflecting mirror (9) and the correction The lower surface of disk (5) is parallel, the reflecting surface plated film of reflecting mirror (9), and face shape PV value is issued less than 0.1 λ, the light source (16) Light irradiates the reflecting mirror by the light-conductive optic fibre (12) after the spectroscope (7), collimation lens (8) (9), it is imaged on the CCD (6) after the light of reflecting mirror (9) reflection is using lens (8), spectroscope (7).

2. polishing panel surface face according to claim 1 shape on-line monitoring device, it is characterized in that the light source (16) is He-Ne light source, wavelength X 632.8nm.

3. carrying out polishing panel surface face shape using polishing panel surface face shape on-line monitoring device described in claim 1 to be monitored online Method, it is characterised in that this method includes the following steps：

1) lathe is allowed to be in shutdown status, cooperation adjustment can be manually rotated platform (2), pitching adjusting mechanism (3) and with two-dimension adjustment The reflecting mirror (9) of frame makes occur the picture of clearly crosshair on the CCD (6)；

2) rotation correction disk (5) manually, remains unchanged the position of crosshair；

3) the practical face shape of one group of inclination angle and monitoring element is measured, system compensation is carried out, eliminates systematic error；

4) monitoring parameters, the inclination angle of continuous on-line monitoring correction disk (5), after handling the angle signal of actual acquisition are set Calculate the practical face shape information of polishing panel surface.