Method and system for manufacturing optical film

Abstract

The invention provides a manufacturing method of an optical film. The method comprises the following steps: executing a first coating procedure to form a first optical film, and measuring the penetration rates of the first optical film at a plurality of time points when the first coating procedure is executed; determining a plurality of parameters in the fitting function according to the time points and the corresponding penetration rates; determining a plating stop point of the second coating procedure according to the fitting function and the parameter; and executing a second coating procedure according to the plating stop point to form a second optical film. Therefore, the plating stopping point can be accurately determined.

Description

Technical Field

[0001] The present disclosure relates to an optical film manufacturing method and a manufacturing system capable of calculating a stop plating point. Background Art

[0002] Optical films are often manufactured using coating methods, such as physical vapor deposition, which presents some challenges, including film thickness control. Precise control of film thickness is critical to optical performance, especially for wavelength films, such as quarter-wavelength films, which require very accurate thickness, which requires precise coating rate control and precise control of the end of coating. How to accurately determine the stop point is a topic of concern to technicians in this field. Summary of the invention

[0003] The disclosed embodiment provides a method for manufacturing an optical film, comprising: performing a first coating process to form a first optical film, measuring the transmittance of the first optical film at multiple time points when performing the first coating process; determining multiple parameters in a fitting function according to these time points and the corresponding transmittances; determining a stop point of a second coating process according to the fitting function and the parameters; and performing a second coating process according to the stop point to form a second optical film.

[0004] In some embodiments, the fitting function includes a plurality of trigonometric functions.

[0005] In some embodiments, the fitting function is expressed as the following mathematical formula 1.

[0006] [Mathematical formula 1]

[0007]

[0008] Where Σ, ω, Ω, Ψ are parameters, k is a constant, t is time, and p is penetration.

[0009] In some embodiments, the step of determining the stop point of the second coating process according to the fitting function and the parameters includes: substituting the predetermined transmittance into the fitting function to obtain the corresponding stop time as the stop point.

[0010] In some embodiments, the first coating process and the second coating process include physical vapor deposition.

[0011] From another perspective, the embodiment of the present disclosure provides a manufacturing system for an optical film, including a coating device and a computing module. The coating device is used to perform a first coating process to form a first optical film, and measure the transmittance of the optical film at multiple time points when performing the first coating process. The computing module is communicatively connected to the coating device, and is used to determine multiple parameters in a fitting function according to these time points and corresponding transmittances. The computing module is used to determine a stop point of a second coating process according to the fitting function and the parameters, and the coating device is used to perform a second coating process according to the stop point to form a second optical film.

[0012] In the above system and method, the stop plating point of the optical film can be accurately calculated.

[0013] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram of a system for manufacturing an optical film according to an embodiment.

[0015] Figure 2 The present invention is a flow chart showing a method for manufacturing an optical film according to an embodiment.

[0016] Figure 3 is a schematic diagram illustrating actual coating and a fitting function according to an embodiment.

[0017]

Main component symbol description

[0018] 100: Manufacturing System

[0019] 110: Computing module

[0020] 120: Coating equipment

[0021] 130: Optical film

[0022] 201-204: Steps

[0023] 300: Chart DETAILED DESCRIPTION

[0024] The terms “first”, “second”, etc. used herein do not particularly refer to an order or sequence, but are only used to distinguish elements or operations described with the same technical terminology.

[0025] Figure 1 is a schematic diagram of a manufacturing system for an optical film according to an embodiment. Figure 1, the manufacturing system 100 includes a computing module 110 and a coating device 120, wherein the computing module 110 can be connected to the coating device 120 by any wired or wireless means. The computing module 110 can be a personal computer, a server or other electronic device with computing capabilities. The coating device 120 is used to execute a coating process to form an optical film 130, and the optical film 130 can be a 1 / 4 film or a non-1 / 4 film, and the present disclosure is not limited thereto. The coating process may include physical vapor deposition, which can be a method such as evaporation (Thermal Evaporation) or sputtering (Sputtering). Therefore, the coating device 120 may include an evaporation system or a sputtering system. The evaporation system uses a heat source (such as an electron beam or resistance heating) to evaporate a solid material into a gaseous state, and then forms a thin film on a cooled substrate. This system usually includes a vacuum chamber, one or more heating sources, one or more evaporation sources, and an instrument for controlling temperature and pressure. The sputtering system uses ions to bombard the target material, ionize it and sputter it onto the substrate to form a thin film. Such a system generally includes a vacuum chamber, one or more ion sources (such as gas plasma), one or more sputtering targets, and instruments for controlling temperature and pressure. The present disclosure is not limited to the above embodiments, and the coating equipment 120 may include any suitable device to perform the coating process. In addition, the coating equipment 120 also includes a suitable sensor or measuring instrument to measure the transmittance of the optical film 130 when implementing the coating process.

[0026] Figure 2 is a flow chart of a method for manufacturing an optical film according to an embodiment. Figure 2 In step 201, a first coating process is performed by the coating device 120 to form a first optical film, and the transmittance of the first optical film at multiple time points is measured when the first coating process is performed. The first coating process includes, for example, physical vapor deposition, and the obtained time and corresponding transmittance are also referred to as training data.

[0027] In step 202, the calculation module 110 determines multiple parameters in the fitting function according to the time points and the corresponding transmittances. The fitting function is derived from the characteristic matrices of the optical film, which includes multiple trigonometric functions. Specifically, the fitting function is expressed as the following mathematical formula 1.

[0028] [Mathematical formula 1]

[0029]

[0030] Wherein Σ, ω, Ω, Ψ are the above-mentioned multiple parameters. k is a constant, for example, 100. t is time. p is the transmittance. Substitute the above-obtained transmittance into p in mathematical formula 1, and substitute each time point into t in mathematical formula 1. As long as the number of time points is greater than or equal to the number of parameters, the parameters such as Σ, ω, Ω, Ψ can be solved. In some embodiments, step 201 can also be performed multiple times, and step 202 is performed after collecting training data of multiple optical films. Derived from the characteristic matrix, the above-mentioned four parameters already include relevant factors such as initial brightness, equivalent admittance of the film surface, refractive index of the film layer, and coating rate. In one experiment, Σ=1.043, ω=1.337, Ω=-0.001, Ψ=0.004795, but the present disclosure is not limited to this.

[0031] In the prior art, a polynomial function is used to simulate the relationship between time and transmittance, but such a function is not accurate. Figure 3 300 is a schematic diagram showing actual coating and fitting function according to an embodiment. The horizontal axis of the graph 300 is time, and the vertical axis is transmittance. The curve labeled "design" represents the transmittance calculated according to the theory; the curve labeled "measurement" represents the transmittance measured when the coating process is actually performed; the curve labeled "fitting" represents the fitting function, from Figure 3 It can be seen that the fitting function is very close to the curve labeled "measurement". If a polynomial function is used to fit the curve labeled "measurement", it may be accurately fitted in a small range, but it will form a large error in a large range.

[0032] Please refer to the reply Figure 3 , in step 203, the calculation module 110 determines the stop point of the second coating process according to the fitting function and the above parameters. For example, the predetermined transmittance can be substituted into p in mathematical formula 1 to obtain the stop time t as the stop point. In some embodiments, if there are multiple solutions (multiple times t produce the same transmittance), the time t within the preset range can be selected as the stop point. In some embodiments, after obtaining the stop point, the thickness of the optical film can also be calculated according to the deposition rate, and the phase of the optical film can also be calculated by adding known parameters such as the wavelength of the light and the refractive index of the optical film. In step 204, the coating equipment 120 performs the second coating process according to the stop point to form the second optical film. The second coating process and the first coating process both include physical vapor deposition, and the same process parameters can be used for both. Through such a process, the time of the coating process can be accurately controlled, and accurate optical properties such as optical film thickness and transmittance can be obtained. Steps 203 and 204 can be repeated to form other optical films.

[0033] Although the present invention has been disclosed as above by way of embodiments, it is not intended to limit the present invention. Any person having ordinary knowledge in the technical field may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A method for manufacturing an optical film, characterized in that: include: Performing a first coating process to form a first optical film, and measuring the transmittance of the first optical film at multiple time points when performing the first coating process; Determine the parameters in the fitting function according to the time point and the corresponding penetration rate; Determining a stop point of the second coating process according to the fitting function and the parameters; as well as The second coating process is performed according to the stop coating point to form a second optical film.

2. The method for manufacturing an optical film according to claim 1, wherein: The fitting function includes a plurality of trigonometric functions.

3. The method for manufacturing an optical film according to claim 2, wherein: The fitting function is expressed as the following mathematical formula 1: [Mathematical formula 1] Wherein Σ, ω, Ω, Ψ are the parameters, k is a constant, t is time, and p is the penetration rate.

4. The method for manufacturing an optical film according to claim 1, wherein: The step of determining the stop point of the second coating process according to the fitting function and the parameter comprises: Substitute the predetermined penetration rate into the fitting function to obtain the corresponding stop time as the stop plating point.

5. The method for manufacturing an optical film according to claim 1, wherein: The first coating process and the second coating process include physical vapor deposition.

6. A system for manufacturing an optical film, characterized in that: include: A coating device, used for performing a first coating procedure to form a first optical film, and measuring the transmittance of the optical film at multiple time points when performing the first coating procedure; as well as A calculation module is communicatively connected to the coating device and is used to determine the parameters in the fitting function according to the time point and the corresponding transmittance. The calculation module is used to determine the stop point of the second coating process according to the fitting function and the parameter, and the coating equipment is used to execute the second coating process according to the stop point to form a second optical film.

7. The optical film manufacturing system according to claim 6, characterized in that: The fitting function includes a plurality of trigonometric functions.

8. The optical film manufacturing system according to claim 7, characterized in that: The fitting function is expressed as the following mathematical formula 1: [Mathematical formula 1] Wherein Σ, ω, Ω, Ψ are the parameters, k is a constant, t is time, and p is the penetration rate.

9. The optical film manufacturing system according to claim 6, characterized in that: The calculation module is used to substitute the predetermined penetration rate into the fitting function to obtain the corresponding stop time as the stop plating point.

10. The optical film manufacturing system according to claim 6, characterized in that: The first coating process and the second coating process include physical vapor deposition.

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