Reflection type coating thickness monitoring system for optical coating

Abstract

The utility model discloses a reflective coating thickness monitoring system for optical coating. The reflective coating thickness monitoring system comprises a monitoring sheet placing device, a transmission device, a driving device and a light control device, the transmission device comprises a rotary transmission cylinder; the monitoring piece placing device comprises a light-operated tray, a monitoring piece fixing seat used for fixing the circular ring monitoring piece is rotatably arranged on the light-operated tray, and the monitoring piece fixing seat is fixedly connected with the rotary transmission cylinder; the circular ring monitoring sheet is divided into a plurality of groups of light-operated monitoring points according to a first rated angle, and coating through holes are formed in a manner of penetrating through the light-operated tray and correspond to the light-operated monitoring points; the light-operated device comprises a light source, a focusing lens and a measuring mechanism, the focus of the focusing lens corresponds to the light-operated monitoring point, the light source is optically connected with the focusing lens through a first optical fiber to output light beams to the circular ring monitoring piece, and the focusing lens is optically connected with the measuring mechanism through a second optical fiber to receive reflected light passing through the circular ring monitoring piece; and the coating thickness is measured according to the change of the reflected light induction light quantity.

Description

Technical Field

[0001] The utility model relates to the technical field of film thickness monitoring systems, and particularly relates to a reflection type film thickness monitoring system for optical coating. Background Technique

[0002] The requirements for film thickness monitoring during the optical coating process are to measure the thickness of the optical thin film in a non-contact, non-destructive, and real-time manner, and to give a control signal in a timely manner when the required thickness is reached.

[0003] There are usually two ways to characterize the monitored film thickness, namely physical thickness and optical thickness. The corresponding film thickness monitoring methods are commonly the quartz crystal oscillator method (crystal control) and the optical film thickness monitoring method (light control). Among them, the optical film thickness monitoring method includes reflection type light control monitoring and direct control type light control monitoring.

[0004] The reflection type light control monitoring mainly plays a role in accurately monitoring the optical coating thickness for irregular film systems. To deposit a filter with relatively high spectral requirements, a relatively high-precision optical monitoring system is required. However, in the existing reflection type light control monitoring, the light spot from the light source on the monitoring film to the monitoring film is relatively large, and the number of monitoring points is relatively small, which affects the number of monitored coating layers that can be deposited. At the same time, the existing system has an angle during monitoring, causing monitoring errors. Therefore, the utility model can provide 60 - 80 monitoring points for the monitoring film. When monitoring, the angle between the incident light and the normal of the monitoring film is 0, and the angle between the reflected light and the normal of the monitoring film is 0. A motor and a positioning magnetic ring are also used for positioning to ensure the positioning accuracy. Content of the Utility Model

[0005] In order to overcome the above technical problems, the utility model discloses a reflection type film thickness monitoring system for optical coating.

[0006] The technical solution adopted by the utility model to achieve the above purpose is:

[0007] A reflection type film thickness monitoring system for optical coating, which includes a monitoring film placement device, a transmission device, a driving device, and a light control device. The monitoring film placement device is arranged in a vacuum chamber;

[0008] The transmission device includes a rotating transmission cylinder, and the rotating transmission cylinder is in transmission connection with the driving device;

[0009] The monitoring film placement device includes a light control tray installed at the bottom of the vacuum chamber. A monitoring film fixing seat for fixing a circular ring monitoring film is rotatably arranged on the light control tray, and the monitoring film fixing seat is fixedly connected with the rotating transmission cylinder;

[0010] The circular monitoring sheet is divided into several groups of light control monitoring points according to a first rated angle. A coating through-hole for coating the circular monitoring sheet is provided through the light control tray, and the coating through-hole is arranged corresponding to the light control monitoring points.

[0011] The light control device includes a light source, a focusing lens, and a measuring mechanism. The focal point of the focusing lens is arranged corresponding to the light control monitoring points. The light source is optically connected to the focusing lens through a first optical fiber to output a light beam to the circular monitoring sheet, and the focusing lens is optically connected to the measuring mechanism through a second optical fiber to receive the reflected light from the circular monitoring sheet and measure the coating thickness according to the change in the sensed light quantity of the reflected light.

[0012] In the above-mentioned reflection type coating thickness monitoring system for optical coating, the driving device includes a motor and a speed reducer arranged at the output end of the motor. The output end of the speed reducer is in transmission connection with the rotary transmission cylinder through a transmission gear.

[0013] In the above-mentioned reflection type coating thickness monitoring system for optical coating, a plurality of groups of positioning magnetic rings are annularly arranged on the outer peripheral surface of the rotary transmission cylinder according to a second rated angle, and each group of the positioning magnetic rings corresponds to a group of the light control monitoring points.

[0014] The driving device further includes a magnetic inductor for sensing the positioning magnetic rings, and the magnetic inductor is electrically connected to the motor.

[0015] In the above-mentioned reflection type coating thickness monitoring system for optical coating, the first rated angle is equal to the second rated angle.

[0016] In the above-mentioned reflection type coating thickness monitoring system for optical coating, the light source includes a halogen lamp and a chopper which are electrically connected. The halogen lamp includes a reflector cup, and the halogen lamp is optically connected to the first optical fiber.

[0017] In the above-mentioned reflection type coating thickness monitoring system for optical coating, the measuring mechanism includes a single wavelength controller, a light sensor, a photoelectric conversion circuit, and a film thickness calculation component which are electrically connected. The single wavelength controller is optically connected to the second optical fiber.

[0018] In the above-mentioned reflection type coating thickness monitoring system for optical coating, the system further includes a mounting base.

[0019] The transmission device further includes a rotating seal seat, a cylindrical roller bearing, and a guide copper sleeve. The rotary transmission cylinder is installed in the mounting base through the rotating seal seat, and the cylindrical roller bearing and the guide copper sleeve are both arranged between the rotating seal seat and the rotary transmission cylinder.

[0020] The above-mentioned reflective coating thickness monitoring system for optical coating, wherein an O-ring seal is provided between the mounting seat and the guide bushing;

[0021] A skeleton oil seal is provided between the rotating transmission cylinder and the guide bushing.

[0022] The above-mentioned reflective coating thickness monitoring system for optical coating, wherein the first optical fiber and the second optical fiber are the first branch end and the second branch end of a Y-shaped bifurcated optical fiber;

[0023] The light control device further includes an optical fiber fixing seat. The common end of the Y-shaped bifurcated optical fiber is arranged on the optical fiber fixing seat, and the focusing lens and the common end of the Y-shaped bifurcated optical fiber are on the same central axis.

[0024] The above-mentioned reflective coating thickness monitoring system for optical coating, wherein the coating through hole, the focusing lens and the common end of the Y-shaped bifurcated optical fiber are on the same central axis.

[0025] The beneficial effects of the present utility model are as follows: The design of the present utility model is reasonable and ingenious. The driving device drives the monitoring film placing device to rotate via the transmission device. By rotating the circular ring monitoring film, the coating thickness difference of different light control monitoring points on the circular ring monitoring film is reduced, and the monitoring accuracy of the coating thickness is optimized by monitoring the change in the light quantity of the light control monitoring points. The circular ring monitoring film is divided into several groups of light control monitoring points according to the first rated angle. During monitoring, the angle between the incident light and the normal of the circular ring monitoring film is 0, and the angle between the reflected light and the normal of the circular ring monitoring film is 0, effectively reducing the influence of the coating thickness difference between adjacent light control monitoring points on the circular ring monitoring film on the accuracy of the light signal, improving the monitoring speed and accuracy of the coating thickness. And the light emitted by the light source converges the light beam on the light control monitoring point through the focusing lens, and its reflected light is reflected to the measuring mechanism through the focusing lens, and the coating thickness is measured according to the change in the light quantity sensed by the reflected light, effectively improving the measuring speed and accuracy of the film thickness. Description of the Drawings

[0026] The present utility model will be further described below with reference to the drawings and embodiments.

[0027] Figure 1 It is a schematic cross-sectional view of the structure of the present utility model;

[0028] Figure 2 is Figure 1 The enlarged schematic view of part A in

[0029] Figure 3 is Figure 1 The enlarged schematic view of part B in Detailed Embodiments

[0030] The present utility model will be further described below through specific embodiments to make the technical solution of the present utility model easier to understand and master, rather than limiting the present utility model.

[0031] Embodiment: Refer to Figures 1 to 3 , a reflection type coating thickness monitoring system for optical coating provided in this embodiment includes a monitoring film placement device, a transmission device, a driving device, and an optical control device. The monitoring film placement device is arranged in a vacuum chamber;

[0032] The transmission device includes a rotating transmission cylinder 11, and the rotating transmission cylinder 11 is in transmission connection with the driving device;

[0033] The monitoring film placement device includes an optical control tray 21 installed at the bottom of the vacuum chamber. A monitoring film fixing seat 22 for fixing the annular monitoring film 23 is rotatably arranged on the optical control tray 21, and the monitoring film fixing seat 22 is fixedly connected to the rotating transmission cylinder 11;

[0034] The annular monitoring film 23 divides a number of optical control monitoring points according to a first rated angle. A coating through hole 24 for coating the annular monitoring film 23 is arranged through the optical control tray 21, and the coating through hole 24 is arranged corresponding to the optical control monitoring points;

[0035] The optical control device includes a light source 31, a focusing lens 32, and a measuring mechanism 33. The focus of the focusing lens 32 is arranged corresponding to the optical control monitoring points. The light source 31 is optically connected to the focusing lens 32 through a first optical fiber to output a light beam to the annular monitoring film 23. The focusing lens 32 is optically connected to the measuring mechanism 33 through a second optical fiber to receive the reflected light from the annular monitoring film 23, and measure the coating thickness according to the change in the amount of light sensed by the reflected light.

[0036] Specifically, the driving device is utilized to drive the monitoring film placing device to rotate via the transmission device. By rotating the annular monitoring film 23, the coating thickness difference of different light control monitoring points on the annular monitoring film 23 is reduced, so as to realize optimizing the monitoring accuracy of the coating thickness by monitoring the change in the light quantity of the light control monitoring points. The annular monitoring film 23 is divided into several groups of light control monitoring points according to the first rated angle. During monitoring, the angle between the incident light and the normal line of the annular monitoring film is 0, and the angle between the reflected light and the normal line of the annular monitoring film is 0, effectively reducing the influence of the coating thickness difference between adjacent light control monitoring points on the annular monitoring film 23 on the accuracy of the light signal, improving the monitoring speed and accuracy of the coating thickness. And the light source 31 emits light, and the light beam is converged on the light control monitoring point through the focusing lens 32. Its reflected light is reflected by the focusing lens 32 to the measuring mechanism 33, and the coating thickness is measured according to the change in the light quantity sensed by the reflected light, effectively improving the measuring speed and accuracy of the film thickness.

[0037] In this embodiment, the annular monitoring film 23 is divided into 60 light control monitoring points in total according to the first rated angle of 6°.

[0038] Preferably, the driving device includes a motor 41 and a speed reducer 42 arranged at the output end of the motor 41. The output end of the speed reducer 42 is in transmission connection with the rotating transmission cylinder 11 through a transmission gear 45. Specifically, the motor uses a Panasonic CONT.TORQUE 1.3N-m servo motor, and the speed reducer 42 uses a KIMPO ABLE REDCER KPL62 5-P1 speed reducer.

[0039] Further, several groups of positioning magnetic rings 43 are annularly arranged on the outer peripheral surface of the rotating transmission cylinder 11 according to the second rated angle, and each group of positioning magnetic rings 43 corresponds to a group of light control monitoring points.

[0040] The driving device further includes a magnetic inductor 44 for sensing the positioning magnetic ring 43, and the magnetic inductor 44 is electrically connected to the motor 41.

[0041] The first rated angle is equal to the second rated angle.

[0042] Specifically, the cooperative setting of the magnetic inductor 44 and the positioning magnetic ring 43 helps to correct the rotation error of the motor 41 and greatly optimize the positioning accuracy of the light control monitoring points. When the motor 41 drives the rotating transmission cylinder 11 to rotate, the magnetic inductor 44 senses the positioning magnetic ring 43, that is, at this time the light control monitoring point rotates to align with the coating through hole 24.

[0043] Preferably, the light source 31 includes a halogen lamp and a chopper connected electrically, the halogen lamp includes a reflector cup, and the halogen lamp is optically connected to the first optical fiber;

[0044] The measuring mechanism 33 includes a single-wavelength controller, a light sensor, a photoelectric conversion circuit and a film thickness calculation component connected electrically, and the single-wavelength controller is optically connected to the second optical fiber.

[0045] Specifically, the light emitted by the light source 31 is transmitted to the focusing lens 32 via the first optical fiber, the focusing lens 32 converges the light beam at the light control monitoring point, after its reflected light passes through the focusing lens 32, it is reflected to the single-wavelength controller via the second optical fiber to receive the monitoring wavelength optical signal, the light quantity value is sensed by the light sensor, and a voltage value is obtained through data processing of the photoelectric conversion circuit, and the film thickness calculation component obtains the coating thickness according to the change of the light quantity value and the voltage value.

[0046] Preferably, the system further includes a mounting base;

[0047] The transmission device further includes a rotating seal seat 12, a cylindrical roller bearing 13 and a guide copper bushing 14. The rotary transmission cylinder 11 is installed in the mounting base through the rotating seal seat 12. The cylindrical roller bearing 13 and the guide copper bushing 14 are both arranged between the rotating seal seat 12 and the rotary transmission cylinder 11. The cylindrical roller bearing 13 and the guide copper bushing 14 effectively improve the rotation accuracy of the rotary transmission cylinder 11 and avoid the problem of swing of the rotary transmission cylinder 11 during the transmission process.

[0048] Furthermore, an O-ring seal 15 is arranged between the mounting base and the guide copper bushing 14;

[0049] A skeleton oil seal 16 is arranged between the rotary transmission cylinder 11 and the guide copper bushing 14; the O-ring seal 15 and the skeleton oil seal 16 ensure that the inside of the vacuum chamber maintains a vacuum-sealed state.

[0050] Specifically, the first optical fiber and the second optical fiber are the first branch end and the second branch end of a Y-shaped bifurcated optical fiber;

[0051] The light control device further includes an optical fiber fixing seat. The common end of the Y-shaped bifurcated optical fiber is arranged on the optical fiber fixing seat, and the focusing lens 32 and the common end of the Y-shaped bifurcated optical fiber are on the same central axis.

[0052] Specifically, the coating through hole 24, the focusing lens 32 and the common end of the Y-shaped bifurcated optical fiber are on the same central axis.

[0053] When the utility model works, it includes the following steps:

[0054] (1) The driving device drives the monitoring sheet placing device to rotate via the transmission device, and further drives the circular monitoring sheet 23 to rotate, so as to enable several groups of the light-controlled monitoring points to sequentially flow through the coating through holes 24;

[0055] (2) Coating the circular monitoring sheet 23 through the coating through holes 24;

[0056] (3) The light source 31 emits light and is transmitted to the focusing lens 32 via the first optical fiber. The focusing lens 32 converges the light beam on the light-controlled monitoring point. After the reflected light passes through the focusing lens 32, it is reflected to the single-wavelength controller via the second optical fiber to receive the monitoring wavelength optical signal. The light quantity value is sensed by the light sensor, and the voltage value is obtained through the data processing of the photoelectric conversion circuit. The film thickness calculation component obtains the coating thickness according to the changes of the light quantity value and the voltage value.

[0057] The design of the present utility model is reasonable and ingenious. The driving device drives the monitoring sheet placing device to rotate via the transmission device, and by rotating the circular monitoring sheet, the coating thickness difference of different light-controlled monitoring points on the circular monitoring sheet is reduced, so as to realize optimizing the monitoring accuracy of the coating thickness by monitoring the light quantity change of the light-controlled monitoring points. The circular monitoring sheet is divided into several groups of light-controlled monitoring points according to the first rated angle. During monitoring, the angle between the incident light and the normal line of the circular monitoring sheet is 0, and the angle between the reflected light and the normal line of the circular monitoring sheet is 0, effectively reducing the influence of the coating thickness difference between adjacent light-controlled monitoring points on the circular monitoring sheet on the accuracy of the optical signal, improving the monitoring speed and accuracy of the coating thickness. Moreover, the light emitted by the light source is converged on the light-controlled monitoring point through the focusing lens, and its reflected light is reflected to the measuring mechanism through the focusing lens, and the coating thickness is measured according to the change of the sensed light quantity of the reflected light, effectively improving the measuring speed and accuracy of the film thickness.

[0058] The above is only the preferred embodiment of the present utility model, and does not impose any form of limitation on the present utility model. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present utility model by using the above-disclosed technical means and technical content, or modify it into an equivalent embodiment with equivalent changes. Therefore, all equivalent changes made according to the shape, structure and principle of the present utility model without departing from the content of the technical solution of the present utility model shall be covered by the protection scope of the present utility model.

Claims

1. A reflective coating thickness monitoring system for optical coating, characterized in that, It includes a monitoring film placement device, a transmission device, a driving device, and a light control device. The monitoring film placement device is arranged in the vacuum chamber; The transmission device includes a rotating transmission cylinder, and the rotating transmission cylinder is in transmission connection with the driving device; The monitoring film placement device includes a light control tray installed at the bottom of the vacuum chamber. A monitoring film fixing seat for fixing a circular ring monitoring film is rotatably arranged on the light control tray, and the monitoring film fixing seat is fixedly connected with the rotating transmission cylinder; The circular ring monitoring film is divided into several groups of light control monitoring points according to a first rated angle. A coating through hole for coating the circular ring monitoring film is arranged through the light control tray, and the coating through hole is arranged corresponding to the light control monitoring points; The light control device includes a light source, a focusing lens, and a measuring mechanism. The focus of the focusing lens is arranged corresponding to the light control monitoring points. The light source is optically connected to the focusing lens through a first optical fiber to output a light beam to the circular ring monitoring film, and the focusing lens is optically connected to the measuring mechanism through a second optical fiber to receive the reflected light from the circular ring monitoring film and measure the coating thickness according to the change in the light quantity sensed by the reflected light.

2. The reflective coating thickness monitoring system for optical coating according to claim 1, wherein The driving device includes a motor and a speed reducer arranged at the output end of the motor. The output end of the speed reducer is in transmission connection with the rotating transmission cylinder through a transmission gear.

3. The reflective coating thickness monitoring system for optical coating according to claim 2, wherein A number of groups of positioning magnetic rings are annularly arranged on the outer peripheral surface of the rotating transmission cylinder according to a second rated angle, and each group of the positioning magnetic rings corresponds to a group of the light control monitoring points; The driving device further includes a magnetic inductor for sensing the positioning magnetic rings, and the magnetic inductor is electrically connected to the motor.

4. The reflective coating thickness monitoring system for optical coating according to claim 3, characterized in that, The first rated angle is equal to the second rated angle.

5. The reflective coating thickness monitoring system for optical coating according to claim 1, characterized in that, The light source includes a halogen lamp and a chopper connected electrically. The halogen lamp includes a reflector cup, and the halogen lamp is optically connected to the first optical fiber.

6. The reflective coating thickness monitoring system for optical coating according to claim 5, characterized in that, The measuring mechanism includes a single wavelength controller, a light sensor, a photoelectric conversion circuit, and a film thickness calculation component connected electrically. The single wavelength controller is optically connected to the second optical fiber.

7. The reflective coating thickness monitoring system for optical coating according to claim 1, wherein The system further includes a mounting seat; The transmission device further includes a rotating seal seat, a cylindrical roller bearing, and a guide copper sleeve. The rotating transmission cylinder is installed in the mounting seat through the rotating seal seat, and the cylindrical roller bearing and the guide copper sleeve are both arranged between the rotating seal seat and the rotating transmission cylinder.

8. The reflective coating thickness monitoring system for optical coating according to claim 7, wherein An O-ring seal is arranged between the mounting seat and the guide copper sleeve; A skeleton oil seal is arranged between the rotating transmission cylinder and the guide copper sleeve.

9. The reflective coating thickness monitoring system for optical coating according to claim 1, wherein The first optical fiber and the second optical fiber are the first branch end and the second branch end of a Y-shaped bifurcated optical fiber; The light control device further includes an optical fiber fixing seat, and the common end of the Y-shaped bifurcated optical fiber is arranged on the optical fiber fixing seat.

10. The reflective coating thickness monitoring system for optical coating according to claim 9, wherein, The coating through hole, the focusing lens, and the common end of the Y-shaped bifurcated optical fiber are on the same central axis.

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