Optical coating machine control method, optical coating machine control system and optical coating system

Abstract

The invention discloses an optical coating machine control method, an optical coating machine control system and an optical coating system, and relates to the field of optical coating, the method comprises the following steps: in a coating process, controlling a bearing part to rotate at a constant speed, and detecting reference light and signal light in real time; the monitoring sheet and the reference hole are located at different positions on the bearing part; the monitoring light forms reference light after passing through the reference hole, and the monitoring light forms signal light after passing through the monitoring sheet; and according to the signal intensity of the reference light and the signal intensity of the signal light, the reference light is attenuated, and the coating process of the evaporation component is controlled so as to control the thickness of the film on the monitoring piece. The light intensity of the reference light can be attenuated, the light intensity difference between the reference light and the signal light is reduced, and the measurement precision of the film thickness is improved.

Description

Technical Field

[0001] The present application relates to the field of optical coating, and particularly to a control method for an optical coating machine, a control system for an optical coating machine, and an optical coating system. Background Art

[0002] In the monitoring of the preparation process of optical thin films, after allowing the monitoring light to pass through the reference light R part, the signal light S part, and the background light Z part respectively, and then being received by the same photodetector to form three parts of optical signals, namely reference light, signal light, and background light, the transmittance of the light passing through the object to be measured can be obtained by comparing these three parts of optical signals: T = (signal light - background light) / (reference light - background light). Among them, the background light signal is a noise signal, which refers to the noise signal generated by the detector and the test equipment itself when no monitoring light is received by the detector.

[0003] As the coating process continues, after multiple layers of films are deposited on the object to be measured, its transmittance continuously decreases, thereby causing the energy of the signal light to decrease, while the energy of the reference light remains unchanged. When the signal light gets closer and closer to the background noise, its signal-to-noise ratio decreases, and the measured signal has a large jitter, which affects the judgment of the film thickness and leads to coating failure.

[0004] In order to improve the measurement accuracy, only the light intensity of the signal light can be increased. Although this can increase the intensity of the transmitted light signal and improve the signal-to-noise ratio of the transmitted light, it also increases the light intensity of the reference light, thereby causing the reference light signal to be saturated or exceed the detection limit of the detector. Summary of the Invention

[0005] The purpose of the present application is to provide a control method for an optical coating machine, a control system for an optical coating machine, and an optical coating system, which can attenuate the light intensity of the reference light, reduce the light intensity difference between the reference light and the signal light, and improve the measurement accuracy of the film thickness.

[0006] To achieve the above purpose, the present application provides the following solutions:

[0007] In a first aspect, the present application provides a control method for an optical coating machine. The optical coating machine includes a carrying component, an evaporation coating component, and a light source component. The carrying component is used to carry a monitoring film and a reference hole. The evaporation coating component is used to coat a film on the monitoring film. The light source component is used to emit monitoring light to the carrying component. The control method for the optical coating machine includes:

[0008] During the coating process, control the carrying component to rotate at a constant speed and detect the reference light and the signal light in real time. The monitoring film and the reference hole are located at different positions on the carrying component. The monitoring light forms the reference light after passing through the reference hole, and the monitoring light forms the signal light after passing through the monitoring film.

[0009] Attenuate the reference light according to the signal intensity of the reference light and the signal intensity of the signal light, and control the coating process of the evaporation component to control the thickness of the film on the monitoring sheet.

[0010] Optionally, attenuating the reference light according to the signal intensity of the reference light and the signal intensity of the signal light specifically includes: at the falling edge of the energy of the signal light, insert a reference light attenuation component between the monitoring light and the carrying component to attenuate the reference light; at the falling edge of the energy of the reference light, remove the reference light attenuation component between the monitoring light and the carrying component.

[0011] In a second aspect, the present application provides an optical coating machine control system. The optical coating machine includes a carrying component, an evaporation component, and a light source component. The carrying component is used to carry a monitoring sheet and a reference hole. The evaporation component is used to coat the monitoring sheet. The light source component is used to emit monitoring light to the carrying component. The optical coating machine control system includes: a reference light attenuation component and a control component;

[0012] The control component is configured to: during the coating process, control the carrying component to rotate at a constant speed, and detect the reference light and the signal light in real time; according to the signal intensity of the reference light and the signal intensity of the signal light, control the reference light attenuation component to attenuate the reference light, and control the coating process of the evaporation component to control the thickness of the film on the monitoring sheet;

[0013] Wherein, the monitoring sheet and the reference hole are located at different positions on the carrying component; the monitoring light forms reference light after passing through the reference hole, and the monitoring light forms signal light after passing through the monitoring sheet.

[0014] Optionally, the monitoring sheet and the reference hole are symmetrically arranged at both ends of the carrying component.

[0015] Optionally, the control component inserts the reference light attenuation component between the monitoring light and the carrying component at the falling edge of the energy of the signal light to attenuate the reference light; the control component removes the reference light attenuation component between the monitoring light and the carrying component at the falling edge of the energy of the reference light.

[0016] Optionally, the reference light attenuation component includes a plurality of attenuation sheets with different attenuation values; the plurality of attenuation sheets are evenly spaced on a ring; the control component determines the attenuation value of the reference light according to the signal intensity of the reference light and the signal intensity of the signal light at the falling edge of the energy of the signal light, and inserts the attenuation sheet with the corresponding attenuation value between the monitoring light and the carrying component to attenuate the reference light.

[0017] Optionally, the control component detects the thickness of the thin film on the monitoring sheet according to the intensity of the signal light and the intensity of the reference light, and controls the coating process of the evaporation component according to the thickness of the thin film on the monitoring sheet, so as to control the thickness of the thin film on the monitoring sheet.

[0018] In a third aspect, the present application provides an optical coating system, including: a carrying component, an evaporation component, a light source component, a reference light attenuation component, and a control component;

[0019] The carrying component is used to carry a monitoring sheet and a reference hole; the monitoring sheet and the reference hole are located at different positions on the carrying component;

[0020] The evaporation component is used to coat the monitoring sheet;

[0021] The light source component is used to emit monitoring light to the carrying component; the monitoring light forms signal light after passing through the monitoring sheet, and the monitoring light forms reference light after passing through the reference hole;

[0022] The control component is used to: during the coating process, control the carrying component to rotate at a constant speed, and detect the reference light and the signal light in real time; according to the signal intensity of the reference light and the signal intensity of the signal light, control the reference light attenuation component to attenuate the reference light, and control the coating process of the evaporation component, so as to control the thickness of the thin film on the monitoring sheet.

[0023] Optionally, the carrying component includes a coating umbrella and a rotating motor; the monitoring sheet and the reference hole are located at different positions on the coating umbrella; the rotating motor is used to drive the coating umbrella to rotate at a constant speed.

[0024] Optionally, the monitoring sheet and the reference hole are symmetrically arranged at both ends of the coating umbrella.

[0025] According to the specific embodiments provided by the present application, the present application has the following technical effects:

[0026] The present application provides an optical coating machine control method, an optical coating machine control system, and an optical coating system. By introducing attenuation during the reference light test and withdrawing the attenuation during the signal light test, the intensity of the monitoring light can be increased, the intensity of the signal light can be increased, but the intensity of the reference light is not increased. Furthermore, the intensity difference between the reference light and the signal light is reduced, the measurement accuracy of the thin film thickness is improved, and the accuracy of the optical coating is improved. Description of the Drawings

[0027] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 Schematic diagram of the structure of an optical coating system provided by an embodiment of the present application;

[0029] Figure 2 Schematic flowchart of a control method for an optical coating machine provided by an embodiment of the present application;

[0030] Figure 3 Curve graph of signal changes during the coating process in an embodiment of the present application;

[0031] Figure 4 Schematic diagram of a reference light attenuation component in an embodiment of the present application.

[0032] Reference numerals: 101 - vacuum system, 102 - coating umbrella, 103 - rotating motor, 104 - electron gun, 105 - light source component, 106 - monitoring film, 107 - reference hole, 108 - control component, 109 - photodetector, 110 - amplifier, 111 - analog-to-digital converter, 112 - computer. Detailed implementation manners

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0034] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below with reference to the drawings and specific implementation manners.

[0035] As Figure 1 shown, the optical coating machine includes a vacuum system 101, a carrier component, an evaporation component, and a light source component 105.

[0036] Both the carrier component and the evaporation component are located inside the vacuum system 101, and the vacuum system 101 is used to ensure and maintain the coating vacuum degree.

[0037] The carrier component is used to carry the monitoring film 106 and the reference hole 107. The carrier component includes a coating umbrella 102 and a rotating motor 103.

[0038] The evaporation coating component is used to coat a film on the monitoring sheet 106. The evaporation coating component includes two electron guns 104, and a thin film is formed by heating and evaporating the coating material with an electron beam.

[0039] The light source component 105 is used to emit monitoring light to the carrying component.

[0040] In an exemplary embodiment, as Figure 2 shown, an optical coating machine control method is provided, which is used to control the above-mentioned optical coating machine. The optical coating machine control method includes the following steps 201 and 202.

[0041] Step 201, during the coating process, control the carrying component to rotate at a constant speed, and detect the reference light and the signal light in real time. The monitoring sheet 106 and the reference hole 107 are located at different positions on the carrying component. The monitoring light forms reference light after passing through the reference hole 107, and the monitoring light forms signal light after passing through the monitoring sheet 106.

[0042] Step 202, according to the signal intensity of the reference light and the signal intensity of the signal light, attenuate the reference light, and control the coating process of the evaporation coating component to control the thickness of the thin film on the monitoring sheet 106.

[0043] Specifically, as Figure 3 shown, at the falling edge of the energy of the signal light, insert a reference light attenuation component between the monitoring light and the carrying component to attenuate the reference light. At the falling edge of the energy of the reference light, remove the reference light attenuation component between the monitoring light and the carrying component. Figure 3 In, R represents the reference light, and S represents the signal light.

[0044] In this application, attenuation is introduced during the reference light test, and the attenuation is withdrawn during the signal light test. Furthermore, by increasing the intensity of the monitoring light, the intensity of the signal light can be increased, but the intensity of the reference light is not increased, enabling the photodetector 109 to operate in the linear region or the test equipment to operate in the low-noise measurement range, and the intensity of the transmitted light can be obtained more accurately, thereby improving the measurement accuracy of the thin film.

[0045] In another exemplary embodiment, an optical coating machine control system is provided, which executes the above-mentioned optical coating machine control method. The optical coating machine control system includes: a reference light attenuation component and a control component 108.

[0046] The control component 108 is configured to: during the film coating process, control the carrier component to rotate at a constant speed, and detect the reference light and the signal light in real time. According to the signal intensity of the reference light and the signal intensity of the signal light, control the reference light attenuation component to attenuate the reference light, and control the film coating process of the evaporation coating component, so as to control the thickness of the film on the monitoring sheet 106.

[0047] Wherein, the monitoring sheet 106 and the reference hole 107 are located at different positions on the carrier component. The monitoring light forms the reference light after passing through the reference hole 107, and the monitoring light forms the signal light after passing through the monitoring sheet 106.

[0048] In a specific application example, the monitoring sheet 106 and the reference hole 107 are symmetrically arranged at both ends of the carrier component.

[0049] The control component 108 inserts the reference light attenuation component between the monitoring light and the carrier component at the falling edge of the energy of the signal light to attenuate the reference light. The control component 108 removes the reference light attenuation component between the monitoring light and the carrier component at the falling edge of the energy of the reference light.

[0050] In a specific application example, as Figure 4 shown, the reference light attenuation component includes a plurality of attenuation sheets with different attenuation values. The plurality of attenuation sheets are evenly spaced on a ring. There is no attenuation in the spaced areas of the attenuation sheets. Figure 4 The shaded part in represents attenuation, and the blank part represents no attenuation.

[0051] The control component 108 determines the attenuation value of the reference light according to the signal intensity of the reference light and the signal intensity of the signal light at the falling edge of the energy of the signal light, and inserts the attenuation sheet with the corresponding attenuation value between the monitoring light and the carrier component to attenuate the reference light.

[0052] In a conventional optical coating machine, the physical distance between the reference light and the signal light is very close. When the coating umbrella 102 rotates, the time difference between the reference light and the signal light detected by the photodetector 109 is very small, and the purpose of attenuating the energy of the reference light without affecting the energy of the signal light cannot be achieved. In this application, the physical space distance between the reference light and the signal light is first increased, so that the time interval for the reference hole 107 and the monitoring sheet 106 to pass through the test area is extended, which is convenient for inserting the attenuation sheet to attenuate the energy of the reference light. The reference hole 107 and the monitoring sheet 106 are symmetrically placed on both sides of the coating umbrella 102 to maximize the time interval between the two signals.

[0053] The reference hole 107 and the monitoring film 106 are distinguished by comparing the dark current time of different lengths in front of the reference hole 107 and the monitoring film 106. The insertion and extraction actions of the attenuation film are triggered at the falling edges of the energies of the reference light and the signal light. The insertion and extraction actions can be completed within 5 seconds. By comparing the time interval between the reference light and the signal light for more than 30 seconds, the result of attenuating the reference light energy without affecting the signal light energy can be obtained.

[0054] The overall working process of the optical coating machine control system is as follows: At the beginning of coating, the ratio of the signal light S to the reference light R is approximately equal to 92%. After the coating starts, it is continuously judged whether the ratio of the signal light S to the reference light R is less than 10%. If it is less than 10%, attenuation films with different attenuation values are sequentially introduced in ascending order to attenuate the reference light.

[0055] In a specific application example, the control component 108 detects the thickness of the thin film on the monitoring film 106 according to the intensity of the signal light and the intensity of the reference light, and controls the coating process of the evaporation component according to the thickness of the thin film on the monitoring film 106 to control the thickness of the thin film on the monitoring film 106.

[0056] In a specific application example, the control component 108 includes a photodetector 109, an amplifier 110, an analog-to-digital converter 111, and a computer 112 connected in sequence. The photodetector 109 converts the optical signal into an electrical signal. The amplifier 110 amplifies the electrical signal to an electrical signal sufficient to be detected by an ammeter. The analog-to-digital converter 111 converts the analog signal output by the amplifier 110 into a digital signal recognizable by the computer 112. The computer 112 calculates the corresponding thin film thickness according to the change of the optical signal and controls the entire coating process.

[0057] This application does not reduce the energy of the signal light, only reduces the energy of the reference light, makes the energies of the reference light and the signal light close, enables the ammeter to work in the optimal range by increasing the amplification factor of the amplifier 110 or increasing the incident light energy, adjusts the noise level to make the noise integrated power zero, improves the signal-to-noise ratio of the system, and thus obtains a stable signal output.

[0058] In another exemplary embodiment, an optical coating system is provided, which includes a carrier component, an evaporation component, a light source component 105, a reference light attenuation component, and a control component 108.

[0059] The carrier component is used to carry the monitoring film 106 and the reference hole 107. The monitoring film 106 and the reference hole 107 are located at different positions on the carrier component. In a specific application example, the carrier component includes a coating umbrella 102 and a rotating motor 103. The monitoring film 106 and the reference hole 107 are located at different positions on the coating umbrella 102. The rotating motor 103 is used to drive the coating umbrella 102 to rotate at a constant speed. Preferably, the monitoring film 106 and the reference hole 107 are symmetrically arranged at both ends of the coating umbrella 102.

[0060] The evaporation coating component is used to coat a film on the monitoring film 106.

[0061] The light source component 105 is used to emit monitoring light to the carrier component. The monitoring light forms signal light after passing through the monitoring film 106, and the monitoring light forms reference light after passing through the reference hole 107.

[0062] The control component 108 is used to: during the film coating process, control the carrier component to rotate at a constant speed, and detect the reference light and the signal light in real time; according to the signal intensity of the reference light and the signal intensity of the signal light, control the reference light attenuation component to attenuate the reference light, and control the film coating process of the evaporation coating component to control the thickness of the film on the monitoring film 106.

[0063] In summary, the beneficial effects of the present application include the following points:

[0064] 1) In order to achieve the purpose of attenuating the intensity of the reference light, it is necessary to increase the spatial distance between the reference light structure part and the signal light structure part, and use the time difference generated during the rotation of the coating umbrella 102 to insert or remove the attenuation sheet in the optical path respectively to achieve the purpose of attenuating the reference light.

[0065] 2) In terms of the coating umbrella 102, the scheme of concentrating the reference light signal, the signal light signal and the dark signal part of the traditional coating umbrella 102 in a small area is changed to arranging the reference light structure part and the signal light structure part at different parts of the coating umbrella 102 respectively, for example, on both sides symmetric about the central axis, and using the time difference when the coating umbrella 102 rotates to these two different parts to achieve the purpose of switching the attenuation sheet.

[0066] 3) Add a switching mechanism for the attenuation sheet in the optical path of the monitoring light to achieve the purpose of switching the attenuation sheet in a short time.

[0067] 4) Increase the dynamic range of signal testing and achieve signal extraction in the case of a small transmittance.

[0068] In this application, all actions of obtaining signals, information or data are carried out on the premise of complying with the corresponding data protection regulations and policies of the country where the location is located and obtaining the authorization given by the owner of the corresponding device.

[0069] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0070] Specific examples are used in this article to elaborate on the principles and implementation manners of this application. The description of the above embodiments is only used to help understand the method and its core idea of this application; at the same time, for those of ordinary skill in the art, according to the idea of this application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to this application.

Claims

1. A control method for an optical coating machine, the optical coating machine comprising a carrying component, an evaporation coating component and a light source component, the carrying component being used for carrying a monitoring film and a reference hole, the evaporation coating component being used for coating the monitoring film, and the light source component being used for emitting monitoring light to the carrying component, characterized in that, The optical coating machine control method includes: During the coating process, controlling the carrying component to rotate at a constant speed, and detecting the reference light and the signal light in real time; the monitoring film and the reference hole are located at different positions on the carrying component; the monitoring light forms the reference light after passing through the reference hole, and the monitoring light forms the signal light after passing through the monitoring film; According to the signal intensity of the reference light and the signal intensity of the signal light, attenuating the reference light, and controlling the coating process of the evaporation component to control the thickness of the film on the monitoring film.

2. The optical coating machine control method according to claim 1, characterized in that, Attenuating the reference light according to the signal intensity of the reference light and the signal intensity of the signal light specifically includes: At the falling edge of the energy of the signal light, inserting a reference light attenuation component between the monitoring light and the carrying component to attenuate the reference light; At the falling edge of the energy of the reference light, removing the reference light attenuation component between the monitoring light and the carrying component.

3. An optical coating machine control system, wherein the optical coating machine includes a carrying component, an evaporation coating component, and a light source component. The carrying component is used to carry a monitoring film and a reference hole. The evaporation coating component is used to coat the monitoring film. The light source component is used to emit monitoring light to the carrying component, and is characterized in that, The optical coating machine control system includes: a reference light attenuation component and a control component; The control component is used for: during the coating process, controlling the carrying component to rotate at a constant speed, and detecting the reference light and the signal light in real time; according to the signal intensity of the reference light and the signal intensity of the signal light, controlling the reference light attenuation component to attenuate the reference light, and controlling the coating process of the evaporation component to control the thickness of the film on the monitoring film; Wherein, the monitoring film and the reference hole are located at different positions on the carrying component; the monitoring light forms the reference light after passing through the reference hole, and the monitoring light forms the signal light after passing through the monitoring film.

4. The optical coating machine control system according to claim 3, characterized in that, The monitoring film and the reference hole are symmetrically arranged at both ends of the carrying component.

5. The optical coating machine control system according to claim 3, characterized in that The control component inserts the reference light attenuation component between the monitoring light and the carrying component at the falling edge of the energy of the signal light to attenuate the reference light; The control component removes the reference light attenuation component between the monitoring light and the carrying component at the falling edge of the energy of the reference light.

6. The optical coating machine control system according to claim 3, characterized in that, The reference light attenuation component includes a plurality of attenuation films with different attenuation values; the plurality of attenuation films are evenly spaced and distributed on a circular ring; The control component determines the attenuation value of the reference light according to the signal intensity of the reference light and the signal intensity of the signal light at the falling edge of the energy of the signal light, and inserts the attenuation film with the corresponding attenuation value between the monitoring light and the carrying component to attenuate the reference light.

7. The optical coating machine control system according to claim 3, characterized in that, The control component detects the thickness of the film on the monitoring film according to the intensity of the signal light and the intensity of the reference light, and controls the coating process of the evaporation component according to the thickness of the film on the monitoring film to control the thickness of the film on the monitoring film.

8. An optical coating system, characterized in that, The optical coating system includes: a carrying component, an evaporation component, a light source component, a reference light attenuation component and a control component; The carrying component is used for carrying the monitoring film and the reference hole; the monitoring film and the reference hole are located at different positions on the carrying component; The evaporation component is used for coating the monitoring film; The light source component is used to emit monitoring light to the carrier component; the monitoring light forms signal light after passing through the monitoring film, and the monitoring light forms reference light after passing through the reference hole; The control component is used to: during the film coating process, control the carrier component to rotate at a constant speed, and detect the reference light and the signal light in real time; according to the signal intensity of the reference light and the signal intensity of the signal light, control the reference light attenuation component to attenuate the reference light, and control the film coating process of the evaporation coating component to control the thickness of the film on the monitoring film.

9. The optical coating system according to claim 8, wherein The carrier component includes a coating umbrella and a rotating motor; The monitoring film and the reference hole are located at different positions on the coating umbrella; The rotating motor is used to drive the coating umbrella to rotate at a constant speed.

10. The optical coating system according to claim 9, characterized in that, The monitoring film and the reference hole are symmetrically arranged at both ends of the coating umbrella.

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