Copper-indium-gallium gradient optical coating for stereoscopic imaging

Abstract

The application provides a copper-indium-gallium gradient optical coating for stereoscopic imaging, a reflective coating is formed by depositing on a substrate surface through a magnetron sputtering process, the reflective coating comprises copper elements, indium elements and gallium elements; the side of the reflective coating in contact with the substrate is an inner layer, and the side away from the substrate is a surface layer; the content of the copper elements increases linearly and continuously from the inner layer to the surface layer along the thickness direction of the reflective coating, the content of the indium elements increases linearly and continuously from the inner layer to the surface layer along the thickness direction of the reflective coating, and the content of the gallium elements decreases linearly and continuously from the inner layer to the surface layer along the thickness direction of the reflective coating. The application forms a blue light prevention selective reflective coating with continuously changing content on the substrate surface through the magnetron sputtering process, the reflective coating has high reflectivity for short wave blue light with a wavelength between 400-450 nm, and high transmittance for visible light in other wavelength ranges.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of reflective coating and relates to a copper-indium-gallium gradient optical coating for stereoscopic imaging. BACKGROUND

[0002] With the wide application of LED display technology in electronic devices, the potential harm of short-wave blue light generated by the LED display technology to human retina has been increasingly concerned. Traditional blue light prevention technologies mostly adopt absorption-type optical filters or ordinary reflective coatings, but there are problems such as poor spectral selectivity and low visible light transmittance, and it is difficult to block 400-450 nm harmful blue light while retaining the transmission performance of 450-500 nm beneficial blue light and long-wave visible light. The existing coating material system is single, the element distribution is uniform, and the gradient regulation of refractive index and reflection characteristics cannot be realized to achieve efficient selective regulation of light waves, so that the blue light blocking efficiency and optical transmission performance are difficult to be considered.

[0003] In recent years, optical materials based on metal elements such as copper, indium and gallium have been explored for use in the blue light protection field due to their unique optical properties. However, single-component or fixed-ratio composite coatings are difficult to coordinate the synergistic effect among high reflectivity, refractive index and absorption rate due to the lack of dynamic regulation of element distribution. In addition, traditional coating processes are prone to cause interface stress concentration and non-uniform optical performance, affecting the bonding strength and long-term stability of the coating and the substrate. How to build a continuous gradient structure inside the coating to achieve efficient reflection of short-wave blue light and lossless transmission of the remaining visible light has become a technical bottleneck that needs to be broken through in this field. SUMMARY

[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide a copper-indium-gallium gradient optical coating for stereoscopic imaging. The present application adopts a magnetron sputtering process to deposit a blue light prevention selective reflection coating with continuously changing content on the surface of a substrate, which has a high reflectivity for short-wave blue light with a wavelength between 400-450 nm, and a high transmittance for visible light in other wavelength ranges (450-780 nm), thereby realizing selective filtering of short-wave blue light.

[0005] To achieve this purpose, the present application adopts the following technical solutions:

[0006] The present application provides a copper-indium-gallium gradient optical coating for stereoscopic imaging, which adopts a magnetron sputtering process to deposit a reflective coating on the surface of a substrate, and the reflective coating includes copper elements, indium elements and gallium elements.

[0007] The side of the reflective coating in contact with the substrate is an inner layer, and the side away from the substrate is a surface layer, the content of the copper element linearly and continuously increases from the inner layer to the surface layer along the thickness direction of the reflective coating, the content of the indium element linearly and continuously increases from the inner layer to the surface layer along the thickness direction of the reflective coating, and the content of the gallium element linearly and continuously decreases from the inner layer to the surface layer along the thickness direction of the reflective coating.

[0008] The application adopts a magnetron sputtering process to deposit a blue light prevention selective reflective coating with continuously changing content on the surface of a substrate, has high reflectivity for short-wave blue light with a wavelength between 400-450 nm, and has high transmittance for visible light in other wavelength ranges (450-780 nm), thereby realizing selective filtering of short-wave blue light.

[0009] The application combines the high reflectivity of the indium element, the high refractive index of the copper element, and the high absorption rate of the gallium element, adjusts the atomic ratio of the three elements in the reflective coating, and obtains a reflective coating with excellent blue light filtering and blocking capacity. Specifically, (1) the indium element has excellent reflectivity in the visible light range, especially for short-wave blue light in the 400-450 nm band, the reflectivity can be as high as 0.8-0.9, which is much higher than the reflectivity of visible light in other wavelength ranges. The content of the indium element in the reflective coating provided by the application linearly and continuously increases from the inner layer to the surface layer, forms an indium-rich region in the surface layer, so that the reflectivity of the surface layer is higher, thereby ensuring that most of the short-wave blue light is reflected in the surface layer of the reflective coating; (2) the copper element has excellent refractive index (1.5-2.5), a small part of the blue light that is not reflected by the surface layer of the reflective coating enters the interior of the reflective coating, and under the action of the high refractive index of the copper element, the blue light is continuously refracted and deflected in the interior of the reflective coating, thereby prolonging the propagation path of the blue light and facilitating the absorption of the blue light; (3) the gallium element has specific absorption characteristics for different wavelength bands, especially strong absorption capacity for ultraviolet light and short-wave blue light. By doping the gallium element into the reflective coating, the small part of the blue light that is not reflected can be completely absorbed; meanwhile, combined with the excellent refractive index of the copper element, an "optical trap" is formed in the interior of the reflective coating, so that the blue light is continuously refracted and deflected in the interior of the reflective coating and is absorbed by the gallium element in the process of refraction and deflection, thereby completely blocking the blue light.

[0010] In the present application, the content of copper element linearly and continuously increases from the inner layer to the surface layer, while the content of gallium element linearly and continuously decreases from the inner layer to the surface layer, so that a copper-rich area and a gallium-poor area are formed on the surface layer of the reflective coating, and a copper-poor area and a gallium-rich area are formed on the inner layer of the reflective coating. The reverse content gradient distribution of copper element and gallium element can ensure that the short-wave blue light is fully refracted and deflected inside the reflective coating, so as to obtain the longest light propagation path, so that the photon energy is fully dissipated, and the subsequent absorption is facilitated. After the blue light is fully refracted and deflected, it can be fully absorbed by the gallium-rich area close to the inner layer before entering the substrate. However, if the short-wave blue light is not fully refracted and deflected, its photon energy is strong, and the gallium element cannot completely absorb it, so that part of the blue light easily passes through the inner layer of the reflective coating and enters the substrate.

[0011] The present application can form copper-rich area, indium-rich area, gallium-poor area, copper-poor area, indium-poor area and gallium-rich area on the surface layer and inner layer of the reflective coating by controlling the sputtering power of copper target, indium target and gallium target, and can also form a continuous content change inside the reflective coating, thereby reducing the element content difference of each area inside the reflective coating, and further reducing the residual internal stress generated in the process of magnetic control sputtering, and improving the hardness, strength and interface bonding performance between the reflective coating and the substrate.

[0012] The magnetic control sputtering process provided by the present application can directly deposit a blue light-proof selective reflective coating on the display device glass, and better solve the harm of high-energy blue light existing in computer display devices, digital electronic product display devices, mobile phones and television display devices to the human eye.

[0013] As a preferred technical solution of the present application, in the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.42 to 0.5, for example, it can be 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49 or 0.5; the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.32 to 0.37, for example, it can be 0.32, 0.325, 0.33, 0.335, 0.34, 0.345, 0.35, 0.355, 0.36, 0.365 or 0.37, but is not limited to the listed values, other values not listed in this range are also applicable, and the rest is In.

[0014] In some optional examples, in the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.55 to 0.63, for example, can be 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62 or 0.63; the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.05 to 0.13, for example, can be 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12 or 0.13, but not limited to the listed values, other values not listed in the range are also applicable, and the rest is In.

[0015] The application particularly limits the atomic proportions of copper element, indium element and gallium element in the inner layer and the surface layer of the reflective coating, which can make the surface layer of the reflective coating have high reflectivity and refractivity, and the inner layer of the reflective coating have high absorption.

[0016] As a preferred technical solution of the application, the thickness of the reflective coating is 420-500nm, for example, can be 420nm, 430nm, 440nm, 450nm, 460nm, 470nm, 480nm, 490nm or 500nm, but not limited to the listed values, other values not listed in the range are also applicable.

[0017] As a preferred technical solution of the application, the reflective coating is prepared by the following method:

[0018] After the substrate is cleaned, it is fixed on a substrate pedestal in a vacuum chamber, the substrate pedestal drives the substrate to rotate and heats the substrate; the copper target, the gallium target and the indium target are fixed in a target base in the vacuum chamber, and the copper target, the gallium target and the indium target are respectively connected to independent radio frequency power sources; the vacuum chamber is evacuated and argon gas is introduced into the vacuum chamber, the radio frequency power sources are started, and a reflective coating with continuously changing content is formed on the surface of the substrate by controlling the sputtering power of the radio frequency power sources.

[0019] As a preferred technical solution of the application, the cleaning method of the substrate is solvent ultrasonic cleaning or ion source cleaning.

[0020] In some optional examples, the cleaning time of the substrate is 10-30min, for example, can be 10min, 12min, 14min, 16min, 18min, 20min, 22min, 24min, 26min, 28min or 30min, but not limited to the listed values, other values not listed in the range are also applicable.

[0021] In some optional examples, after cleaning, the substrate is placed in an oven for drying.

[0022] In some optional examples, the drying temperature of the oven is 100-150℃, for example, it can be 100℃, 105℃, 110℃, 115℃, 120℃, 125℃, 130℃, 135℃, 140℃, 145℃ or 150℃, but not limited to the listed values, and other values not listed in the range are also applicable.

[0023] The reflective coating provided by the application is particularly suitable for glass substrate surfaces. Because the glass substrate surface has strong adsorption, a large amount of dust, grease, impurities and particles and other pollutants will be adsorbed on the surface during long-term storage, resulting in a decrease in the surface cleanliness of the glass substrate. The surface cleanliness of the glass substrate directly affects the adhesion of the reflective coating on the glass substrate surface, and even causes part of the reflective coating to fall off; at the same time, pinholes and speckles and other defects will also be generated on the surface of the reflective coating. Therefore, the glass substrate needs to be thoroughly cleaned before magnetron sputtering.

[0024] The application preferably uses solvent ultrasonic cleaning. The ultrasonic oscillation frequency of the solvent cleaning can be selected to be 20-50kHz. The cavitation energy generated by liquid oscillation can shake off impurities from the surface of the glass substrate, so that the glass substrate has high cleanliness, greatly enhances the surface processing performance of the glass substrate, improves the adhesion of the reflective coating and the glass substrate, and effectively reduces the surface defects of the reflective coating, which plays an important role in improving the process yield in actual production.

[0025] As a preferred technical solution of the application, the rotation speed of the substrate is 10-30r / min, for example, it can be 10r / min, 12r / min, 14r / min, 16r / min, 18r / min, 20r / min, 22r / min, 24r / min, 26r / min, 28r / min or 30r / min, but not limited to the listed values, and other values not listed in the range are also applicable.

[0026] In some optional examples, the heating temperature of the substrate is 400-500℃, for example, it can be 400℃, 410℃, 420℃, 430℃, 440℃, 450℃, 460℃, 470℃, 480℃, 490℃ or 500℃, but not limited to the listed values, and other values not listed in the range are also applicable.

[0027] The substrate temperature has a significant influence on the performance of the reflective coating, the heating temperature of the substrate can change the activity of copper particles, indium particles and gallium particles diffusing on the surface of the substrate, thereby affecting the deposition morphology, growth mode and crystallization degree of the reflective coating, and the crystallization degree and surface roughness of the reflective coating will inevitably affect the reflection and refraction characteristics of the surface layer; in addition, when the surface layer of the reflective coating has a certain rough structure, the visible light with a wavelength range of 450-780 nm can produce multiple diffuse reflection and multi-angle refraction on the surface of the reflective coating, thereby increasing the transmittance of other wave bands of visible light on the basis of blocking short-wave blue light.

[0028] As a preferred technical solution of the present application, the sputtering power of the radio frequency power supply of the copper target is uniformly increased from 30-40W to 50-70W, for example, it can be uniformly increased from 30W to 50W, from 31W to 52W, from 32W to 54W, from 33W to 56W, from 34W to 58W, from 35W to 60W, from 36W to 62W, from 37W to 64W, from 38W to 66W, from 39W to 68W or from 40W to 70W, but not limited to the listed values, other values not listed in this range are also applicable.

[0029] In some optional examples, the sputtering power of the radio frequency power supply of the indium target is uniformly increased from 50-60W to 80-90W, for example, it can be uniformly increased from 50W to 80W, from 51W to 81W, from 52W to 82W, from 53W to 83W, from 54W to 84W, from 55W to 85W, from 56W to 86W, from 57W to 87W, from 58W to 88W, from 59W to 89W or from 60W to 90W, but not limited to the listed values, other values not listed in this range are also applicable.

[0030] In some optional examples, the sputtering power of the radio frequency power supply of the gallium target is uniformly decreased from 120-130W to 40-60W, for example, it can be uniformly decreased from 120W to 40W, from 121W to 42W, from 122W to 44W, from 123W to 46W, from 124W to 48W, from 125W to 50W, from 126W to 52W, from 127W to 54W, from 128W to 56W, from 129W to 58W, or from 130W to 60W, but not limited to the listed values, other values not listed in this range are also applicable.

[0031] The sputtering power has a significant influence on the deposition rate, surface morphology and crystallization degree of the reflective coating during the deposition process, thereby affecting the reflectivity and refractivity of the surface layer of the reflective coating, and the size of the sputtering power directly determines the energy of the argon ion bombarding the surface of the target material and the energy of the sputtered target material particles during the deposition process of the reflective coating, thereby affecting the deposition rate of the reflective coating, if the sputtering power is too low, the energy of the incident argon ion cannot reach the sputtering threshold of the corresponding target material, and a continuous and stable sputtering phenomenon cannot be generated, thereby affecting the thickness and uniformity of the reflective coating, if the sputtering power is too large, the ionization rate of the gas in the vacuum cavity and the sputtering energy will be enhanced, and the phenomenon of injecting the substrate will occur, in addition, too high sputtering power will cause certain damage to the equipment.

[0032] The present application particularly limits the numerical range of the initial value and the terminal value of the sputtering power of each target material, and in particular, the terminal value of the sputtering power will directly affect the surface roughness of the reflective coating, and the surface roughness of the reflective coating will further affect the reflectivity of the surface layer to the short-wave blue light of the 400-450nm wave band and the transmittance of the visible light of the 450-780nm wave band.

[0033] The surface of the reflective coating formed after deposition has a rough structure formed by a plurality of protrusions, by controlling the sputtering power at the sputtering end point of each target material, the distance between the protrusions of the surface layer of the reflective coating can be controlled to be less than 780nm, so that the visible light of the 450-780nm wave band can be reflected multiple times between the protrusions, thereby reducing the reflectivity of the surface layer of the reflective coating to the visible light of the 450-780nm wave band, and thereby enhancing the transmittance of the reflective coating to the visible light of the 450-780nm wave band, at the same time, since the distance between the protrusions of the surface layer of the reflective coating is much larger than the wavelength of the short-wave blue light (400-450nm), the short-wave blue light is mainly reflected on the surface layer of the reflective coating, combined with the high reflectivity of the indium-rich region of the surface layer, the reflectivity of the surface layer of the reflective coating to the short-wave blue light is further improved. Therefore, by controlling the sputtering power at the sputtering end point of different target materials, the surface roughness of the surface layer of the reflective coating can be adjusted, and the blocking of the short-wave blue light of the 400-450nm wave band and the transmission of the visible light of the 450-780nm wave band are finally realized.

[0034] When the sputtering power at the sputtering end point is too low, the roughness of the reflective coating surface is too low, the distance between the surface layer protrusions is too large, the reflectivity of the reflective coating surface layer to visible light is increased, and finally the transmittance of the reflective coating to the visible light in the 450-780 nm wave band is affected. With the increase of the sputtering power, the energy of the sputtered target particles gradually increases, the bombardment effect of the high-energy target particles on the substrate also gradually increases, the diffusion rate of the target particles on the substrate increases, and the atoms or atomic groups on the reflective coating surface gradually migrate, collide and merge, and finally form a number of island clusters, resulting in an increase in the roughness of the reflective coating surface layer. When the sputtering power exceeds the upper limit of the range defined by the present application, the surface roughness of the reflective coating is too high, the distance between the adjacent protrusions on the surface layer is less than the wavelength of the short-wave blue light, and the reflection of the short-wave blue light is affected, and finally the barrier rate of the reflective coating to the short-wave blue light in the 400-450 nm wave band is affected.

[0035] As a preferred technical solution of the present application, the deposition time of the magnetron sputtering is 10-30 min, for example, it can be 10 min, 12 min, 14 min, 16 min, 18 min, 20 min, 22 min, 24 min, 26 min, 28 min or 30 min, but not limited to the listed values, other values not listed in this range are also applicable.

[0036] It should be noted that the sputtering power of each target provided by the present application changes linearly and continuously, and the adjustment rate can be calculated according to the initial value and the final value of the sputtering power and the deposition time of co-sputtering. For example, if the sputtering power of the copper target is uniformly increased from 30 W to 50 W, the deposition time is 20 min, and the sputtering power should be uniformly increased at a rate of 1 W / min. Therefore, the adjustment rate of the sputtering power of each target is not additionally limited by the present application.

[0037] As a preferred technical solution of the present application, the vacuum degree in the vacuum chamber is 1x10 -5 Pa, for example, it can be 1x10 -3 Pa, 3x10 -5 Pa, 5x10 -5 Pa, 7x10 -5 Pa, 9x10 -5 Pa, 1x10 -4 Pa, 3x10 -4 Pa, 5x10 -4 Pa, 7x10 -4 Pa, or 9x10 -3 Pa, but not limited to the listed values, other values not listed in this range are also applicable.

[0038] The vacuum degree in the vacuum chamber is 1x10 -5 -1x10 -3 Pa. The vacuum degree will change the number of residual gas molecules in the vacuum chamber. The higher the vacuum degree, the smaller the chance of collision between target atoms and other molecules during the transmission to the substrate, and the greater the kinetic energy of the deposition molecules reaching the substrate, and the denser the reflection coating.

[0039] As a preferred technical solution of the present application, the purity of the argon gas is above 99.999%.

[0040] In some optional examples, the flow rate of the argon gas is 20-30 sccm, for example, it can be 20 sccm, 21 sccm, 22 sccm, 23 sccm, 24 sccm, 25 sccm, 26 sccm, 27 sccm, 28 sccm, 29 sccm or 30 sccm, but not limited to the listed values, other values not listed in this range are also applicable.

[0041] In some optional examples, the argon gas is introduced at a pressure of 0.8-1.2 Pa, for example, it can be 0.8 Pa, 0.85 Pa, 0.9 Pa, 0.95 Pa, 1.0 Pa, 1.05 Pa, 1.1 Pa, 1.15 Pa or 1.2 Pa, but not limited to the listed values, other values not listed in this range are also applicable.

[0042] Exemplarily, the present application provides a preparation method of copper-indium-gallium gradient optical coating for stereoscopic imaging, which specifically comprises the following steps:

[0043] The substrate is cleaned by solvent ultrasonic cleaning or ion source cleaning, and after cleaning for 10-30 min, the substrate is placed in an oven at 100-150℃ for drying. The cleaned substrate is fixed on the substrate pedestal in the vacuum chamber, and the substrate pedestal drives the substrate to rotate at a speed of 10-30 r / min and heats the substrate to 400-500℃;

[0044] The copper target, gallium target and indium target are fixed in the target material pedestal in the vacuum chamber, and the copper target, gallium target and indium target are respectively connected to independent radio frequency power sources;

[0045] The vacuum chamber is evacuated to 1x10 -5 -1x10 -3 Pa, and argon gas with a purity of above 99.999% is introduced into the vacuum chamber at a flow rate of 20-30 sccm and a pressure of 0.8-1.2 Pa;

[0046] Start the radio frequency power supply and adjust the sputtering power of each radio frequency power supply, wherein the sputtering power of the radio frequency power supply of the copper target is uniformly increased from 30-40W to 50-70W, the sputtering power of the radio frequency power supply of the indium target is uniformly increased from 50-60W to 80-90W, the sputtering power of the radio frequency power supply of the gallium target is uniformly reduced from 120-130W to 40-60W, and after co-sputtering for 10-30min, a reflective coating with a thickness of 420-500nm is deposited on the surface of the substrate.

[0047] In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) is in the range of 0.42-0.5, the atomic ratio of Ga / (Cu+In+Ga) is in the range of 0.32-0.37, and the rest is In. In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) is in the range of 0.55-0.63, the atomic ratio of Ga / (Cu+In+Ga) is in the range of 0.05-0.13, and the rest is In.

[0048] Compared with the prior art, the present application has the following advantages:

[0049] The present application adopts a magnetron sputtering process to deposit a blue light prevention selective reflective coating with continuously changing content on the surface of the substrate, which has a high reflectivity for short-wave blue light with a wavelength between 400-450nm, and a high transmittance for visible light in other wavelength ranges (450-780nm), thereby realizing selective filtering of short-wave blue light.

[0050] The present application comprehensively combines the high reflectivity of indium element, the high refractive index of copper element and the high absorption rate of gallium element, and obtains a reflective coating with excellent blue light filtering and blocking capability by adjusting the atomic ratio of the three elements in the reflective coating. Specifically, (1) indium element has excellent reflectivity in the visible light range, especially for short-wave blue light in the 400-450 nm band, its reflectivity can be as high as 0.8-0.9, which is much higher than the reflectivity of visible light in other wavelength ranges. In the reflective coating provided by the present application, the content of indium element increases linearly and continuously from the inner layer to the surface layer, forming an indium-rich region on the surface layer of the reflective coating, so that the reflectivity of the surface layer is higher, thereby ensuring that most of the short-wave blue light is reflected on the surface layer of the reflective coating; (2) copper element has excellent refractive index (1.5-2.5), and a small part of blue light that is not reflected by the surface layer of the reflective coating enters the inside of the reflective coating, and under the action of the high refractive index of copper element, the blue light is continuously refracted and deflected inside the reflective coating, thereby prolonging the propagation path of the blue light and facilitating the absorption of the blue light; (3) gallium element has specific absorption characteristics for different wavelength bands of light, especially strong absorption ability for ultraviolet light and short-wave blue light. By doping it into the reflective coating, all the small part of blue light that is not reflected can be absorbed. At the same time, combined with the excellent refractive index of copper element, an "optical trap" is formed inside the reflective coating, so that the blue light is continuously refracted and deflected inside the reflective coating and is absorbed by the gallium element in the process of refraction and deflection, and finally the complete blocking of the blue light is realized.

[0051] In the present application, the content of copper element increases linearly and continuously from the inner layer to the surface layer, while the content of gallium element decreases linearly and continuously from the inner layer to the surface layer, thereby forming a copper-rich region and a gallium-poor region on the surface layer of the reflective coating, and forming a copper-poor region and a gallium-rich region on the inner layer of the reflective coating. The reverse content gradient distribution of copper element and gallium element can ensure that the short-wave blue light is fully refracted and deflected inside the reflective coating, thereby obtaining the longest light propagation path, so that the photon energy is fully dissipated, facilitating subsequent absorption. After the blue light is fully refracted and deflected, it can be fully absorbed by the gallium-rich region close to the inner layer before entering the substrate. However, if the short-wave blue light is not fully refracted and deflected, its photon energy is strong, and the gallium element cannot completely absorb it, so part of the blue light can easily pass through the inner layer of the reflective coating and enter the substrate.

[0052] By controlling the sputtering power of the copper target, indium target and gallium target, the present application forms a copper-rich region, an indium-rich region, a gallium-poor region, a copper-poor region, an indium-poor region and a gallium-rich region on the surface layer and the inner layer of the reflective coating, and also forms a continuous content change inside the reflective coating, thereby reducing the element content difference between the regions inside the reflective coating, and further reducing the residual internal stress generated in the process of magnetic sputtering, improving the hardness, strength and interface bonding performance between the reflective coating and the substrate.

[0053] The magnetron sputtering process provided by the application can directly coat the selective reflection coating film for preventing blue light on the display device glass, and better solves the harm of high-energy blue light existing in computer display devices, digital electronic product display devices, mobile phones and television display devices to human eyes. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 The wavelength-reflection rate curve of the surface layer of the reflection coating film prepared in the embodiment 1 of the application is shown in the figure. DETAILED DESCRIPTION

[0055] The technical solutions of the application will be described in detail below with specific embodiments and their drawings. The embodiments described herein are specific specific embodiments of the application, which are used to explain the concept of the application; all the descriptions are explanatory and exemplary, and should not be understood as limiting the embodiments of the application and the protection scope of the application. In addition to the embodiments described herein, those skilled in the art can also employ other technical solutions which are obvious based on the content disclosed in the claims and the description of the application, which include technical solutions of any obvious replacement and modification of the embodiments described herein.

[0056] Embodiment 1

[0057] The embodiment provides a preparation method of copper-indium-gallium gradient optical coating film for stereoscopic imaging, and the preparation method specifically comprises the following steps:

[0058] The glass substrate is subjected to solvent ultrasonic cleaning, and after cleaning for 10 minutes, the glass substrate is placed in an oven at 100 DEG C for drying. The cleaned glass substrate is fixed on a substrate base in a vacuum chamber, and the substrate base drives the glass substrate to rotate at a speed of 10 r / min and heats the glass substrate to 400 DEG C.

[0059] The copper target, the gallium target and the indium target are fixed in the target base in the vacuum chamber, and the copper target, the gallium target and the indium target are respectively connected to independent radio frequency power sources.

[0060] The vacuum chamber is pumped to 1x10 -3 Pa, and the vacuum chamber is filled with argon with a purity of more than 99.999%, the flow rate of the argon is 20 sccm, and the gas pressure is 0.8 Pa.

[0061] The radio frequency power sources are started, and the sputtering power of each radio frequency power source is adjusted, wherein the sputtering power of the radio frequency power source of the copper target is uniformly increased from 30 W to 50 W, the sputtering power of the radio frequency power source of the indium target is uniformly increased from 50 W to 80 W, and the sputtering power of the radio frequency power source of the gallium target is uniformly decreased from 120 W to 40 W. After a total sputtering of 10 minutes, a reflection coating film with a thickness of 420 nm is formed on the surface of the glass substrate.

[0062] In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.42, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.32, and the rest is In. In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.55, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.05, and the rest is In.

[0063] Figure 1 The wavelength-reflectivity curve of the surface layer of the reflective coating prepared in this example is shown in FIG. 2. Figure 1 It can be seen that the reflectivity of the surface layer of the reflective coating to short-wave blue light in the wavelength range of 400-450 nm can reach 98%.

[0064] Example 2

[0065] The present example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which specifically comprises the following steps:

[0066] The glass substrate is subjected to solvent ultrasonic cleaning, and after cleaning for 15 min, the glass substrate is placed in an oven at 110°C for drying. The cleaned glass substrate is fixed on a substrate base in a vacuum chamber, and the substrate base drives the glass substrate to rotate at a speed of 15 r / min and heats the glass substrate to 420°C.

[0067] The copper target, the gallium target, and the indium target are fixed in a target base in the vacuum chamber, and the copper target, the gallium target, and the indium target are respectively connected to independent radio frequency power sources.

[0068] The vacuum chamber is evacuated to 5x10 -3 Pa, and argon gas with a purity of 99.999% or above is introduced into the vacuum chamber at a flow rate of 22 sccm and a pressure of 0.9 Pa.

[0069] The radio frequency power sources are started, and the sputtering power of each radio frequency power source is adjusted. Specifically, the sputtering power of the radio frequency power source of the copper target is uniformly increased from 32 W to 55 W, the sputtering power of the radio frequency power source of the indium target is uniformly increased from 52 W to 82 W, and the sputtering power of the radio frequency power source of the gallium target is uniformly decreased from 122 W to 45 W. After co-sputtering for 15 min, a reflective coating with a thickness of 430 nm is formed on the surface of the glass substrate.

[0070] In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.45, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.33, and the rest is In. In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.58, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.06, and the rest is In.

[0071] Example 3

[0072] The embodiment provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, and the preparation method specifically comprises the following steps:

[0073] The glass substrate is subjected to ion source cleaning, and after cleaning for 20 minutes, the glass substrate is placed into an oven at 120 DEG C for drying. The cleaned glass substrate is fixed on a substrate base in a vacuum chamber, and the substrate base drives the glass substrate to rotate at a speed of 20 r / min and heat the glass substrate to 450 DEG C.

[0074] The copper target, the gallium target and the indium target are fixed in a target base in the vacuum chamber, and the copper target, the gallium target and the indium target are respectively connected to independent radio frequency power sources.

[0075] The vacuum chamber is vacuumized to 1x10 -4 Pa, pure argon with a purity of 99.999% or above is introduced into the vacuum chamber, the flow rate of the argon is 25 sccm, and the gas pressure is 1 Pa.

[0076] The radio frequency power sources are started, and the sputtering power of each radio frequency power source is adjusted. The sputtering power of the radio frequency power source of the copper target is uniformly increased from 35 W to 60 W, the sputtering power of the radio frequency power source of the indium target is uniformly increased from 55 W to 85 W, and the sputtering power of the radio frequency power source of the gallium target is uniformly decreased from 125 W to 50 W. After co-sputtering for 20 minutes, a reflective coating with a thickness of 450 nm is formed on the surface of the glass substrate.

[0077] In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.46, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.35, and the rest is In. In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.6, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.08, and the rest is In.

[0078] Example 4

[0079] The embodiment provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, and the preparation method specifically comprises the following steps:

[0080] The glass substrate is subjected to ion source cleaning, and after cleaning for 25 minutes, the glass substrate is placed into an oven at 140 DEG C for drying. The cleaned glass substrate is fixed on a substrate base in a vacuum chamber, and the substrate base drives the glass substrate to rotate at a speed of 25 r / min and heat the glass substrate to 480 DEG C.

[0081] The copper target, the gallium target and the indium target are fixed in a target base in the vacuum chamber, and the copper target, the gallium target and the indium target are respectively connected to independent radio frequency power sources.

[0082] The vacuum chamber is pumped to 5x10 -4 The vacuum chamber is pumped to 5x10

[0083] The RF power is started and the sputtering power of each RF power source is adjusted, wherein the sputtering power of the RF power source of the copper target is uniformly increased from 38 W to 65 W, the sputtering power of the RF power source of the indium target is uniformly increased from 58 W to 88 W, and the sputtering power of the RF power source of the gallium target is uniformly decreased from 128 W to 55 W. After co-sputtering for 25 min, a reflective coating with a thickness of 480 nm is formed on the surface of the glass substrate.

[0084] In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.48, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.36, and the rest is In. In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.62, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.1, and the rest is In.

[0085] Example 5

[0086] The present embodiment provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which specifically comprises the following steps:

[0087] The glass substrate is cleaned by ion source for 30 min, and then dried in an oven at 150°C. The cleaned glass substrate is fixed on a substrate pedestal in the vacuum chamber, and the substrate pedestal drives the glass substrate to rotate at a speed of 30 r / min and heats the glass substrate to 500°C.

[0088] The copper target, the gallium target, and the indium target are fixed in the target material pedestal in the vacuum chamber, and the copper target, the gallium target, and the indium target are respectively connected to independent RF power sources.

[0089] The vacuum chamber is pumped to 1x10 -5 The vacuum chamber is pumped to 1x10

[0090] The RF power is started and the sputtering power of each RF power source is adjusted, wherein the sputtering power of the RF power source of the copper target is uniformly increased from 40 W to 70 W, the sputtering power of the RF power source of the indium target is uniformly increased from 60 W to 90 W, and the sputtering power of the RF power source of the gallium target is uniformly decreased from 130 W to 60 W. After co-sputtering for 30 min, a reflective coating with a thickness of 500 nm is formed on the surface of the glass substrate.

[0091] In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.5, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.37, and the rest is In. In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.63, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.13, and the rest is In.

[0092] Comparative Example 1

[0093] The present comparative example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which is different from Example 1 in that the sputtering power of the radio frequency power supply of the copper target is uniformly increased from 30 W to 40 W, the overall co-sputtering time remains unchanged, and the other process parameters and operation steps are completely the same as those of Example 1.

[0094] Comparative Example 2

[0095] The present comparative example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which is different from Example 1 in that the sputtering power of the radio frequency power supply of the copper target is uniformly increased from 30 W to 80 W, the overall co-sputtering time remains unchanged, and the other process parameters and operation steps are completely the same as those of Example 1.

[0096] Comparative Example 3

[0097] The present comparative example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which is different from Example 1 in that the sputtering power of the radio frequency power supply of the indium target is uniformly increased from 50 W to 70 W, the overall co-sputtering time remains unchanged, and the other process parameters and operation steps are completely the same as those of Example 1.

[0098] Comparative Example 4

[0099] The present comparative example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which is different from Example 1 in that the sputtering power of the radio frequency power supply of the indium target is uniformly increased from 50 W to 100 W, the overall co-sputtering time remains unchanged, and the other process parameters and operation steps are completely the same as those of Example 1.

[0100] Comparative Example 5

[0101] The present example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which is different from Example 1 in that the sputtering power of the radio frequency power supply of the gallium target is uniformly reduced from 120 W to 30 W, the overall co-sputtering time remains unchanged, and the other process parameters and operation steps are completely the same as those of Example 1.

[0102] Comparative Example 6

[0103] The comparative example provides a preparation method of a copper-indium-gallium gradient optical coating for stereoscopic imaging, which is different from example 1 in that the sputtering power of the radio frequency power supply of the gallium target is uniformly reduced from 120 W to 70 W, the overall sputtering time remains unchanged, and the other process parameters and operation steps are completely the same as those of example 1.

[0104] The reflectance coating provided by examples 1-5 and comparative examples 1-6 is tested for blue light blocking rate of 400-450 nm and visible light transmittance of 450-780 nm, and the test results are shown in Table 1.

[0105] Table 1 Performance test results of the reflectance coating provided by examples 1-5 and comparative examples 1-6

[0106] 400-450 nm blue light barrier % transmittance 450-780 nm visible light barrier % transmittance Example 1 98.3 93.6 Example 2 98.5 94.0 Example 3 99.2 94.8 Example 4 99.8 96.5 Example 5 99.4 95.2 Comparative Example 1 75.3 85.8 Comparative Example 2 68.6 90.3 Comparative Example 3 84.5 77.4 Comparative Example 4 53.1 92.6 Comparative Example 5 78.8 80.2 Comparative Example 6 60.2 91.5

[0107] As can be seen from the test data provided in Table 1, the reflectance coating prepared in examples 1-5 has excellent blue light blocking ability and visible light transmittance, can filter more than 98% of short-wave blue light in visible light, and the transmittance of other wavelengths of visible light can be as high as 95%.

[0108] As can be seen from the test data of examples 1, comparative example 1 and comparative example 2, in comparative example 1, the sputtering power of the copper target is low at the end of sputtering, on the one hand, the energy of the incident argon ions cannot reach the sputtering threshold of the copper target, and a stable sputtering phenomenon cannot be produced, on the other hand, it will cause the surface roughness of the reflectance coating to decrease, the refractive index of the surface layer of the reflectance coating to decrease, and finally affect the transmittance of the reflectance coating to visible light of 450-780 nm. In comparative example 2, the sputtering power of the copper target is high, which causes the surface roughness of the reflectance coating to be high, the distance between adjacent protrusions on the surface layer to be less than the wavelength of short-wave blue light, and thus the reflection of short-wave blue light to be affected, and finally the blocking rate of short-wave blue light to decrease.

[0109] As can be seen from the test data of examples 1, comparative example 3 and comparative example 4, in comparative example 3, the sputtering power of the indium target is low at the end of sputtering, on the one hand, the energy of the incident argon ions cannot reach the sputtering threshold of the indium target, and a stable sputtering phenomenon cannot be produced, on the other hand, it will cause the surface roughness of the reflectance coating to decrease, the refractive index of the surface layer of the reflectance coating to decrease, and finally affect the transmittance of the reflectance coating to visible light of 450-780 nm. In comparative example 4, the sputtering power of the indium target is high, which causes the surface roughness of the reflectance coating to be high, the distance between adjacent protrusions on the surface layer to be less than the wavelength of short-wave blue light, and thus the reflection of short-wave blue light to be affected, and finally the blocking rate of short-wave blue light to decrease.

[0110] The test data from Examples 1, 5, and 6 show that in Comparative Example 5, the sputtering power of the gallium target was low at the end of sputtering. On one hand, the energy of the incident argon ions did not reach the sputtering threshold of the gallium target, preventing a continuous and stable sputtering phenomenon. On the other hand, this led to a decrease in the surface roughness of the reflective coating, resulting in a decrease in the refractive index of the reflective coating surface, ultimately affecting the transmittance of the reflective coating for visible light in the 450-780 nm wavelength range. In Comparative Example 6, the sputtering power of the gallium target was high, resulting in a higher surface roughness of the reflective coating. This caused the spacing between adjacent protrusions on the surface to be smaller than the wavelength of short-wavelength blue light, thus affecting the reflection of short-wavelength blue light and ultimately reducing the blocking rate of short-wavelength blue light.

[0111] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A copper indium gallium gradient optical coating for stereoscopic imaging, characterized in that, A reflective coating is deposited on the substrate surface using a magnetron sputtering process, wherein the reflective coating comprises copper, indium, and gallium. The side of the reflective coating that contacts the substrate is the inner layer, and the side that faces away from the substrate is the outer layer. The content of copper increases linearly and continuously from the inner layer to the outer layer along the thickness direction of the reflective coating. The content of indium increases linearly and continuously from the inner layer to the outer layer along the thickness direction of the reflective coating. The content of gallium decreases linearly and continuously from the inner layer to the outer layer along the thickness direction of the reflective coating. In the inner layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.42 to 0.5, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.32 to 0.37, and the remainder is In; In the surface layer of the reflective coating, the atomic ratio of Cu / (Cu+In+Ga) ranges from 0.55 to 0.63, the atomic ratio of Ga / (Cu+In+Ga) ranges from 0.05 to 0.13, and the remainder is In.

2. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 1, characterized in that, The thickness of the reflective coating is 420-500 nm.

3. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 1, characterized in that, The reflective coating is prepared using the following method: After cleaning, the substrate is fixed on the substrate stage in the vacuum chamber. The substrate stage drives the substrate to rotate and heat the substrate. Copper, gallium and indium targets are fixed in the target base in the vacuum chamber. The copper, gallium and indium targets are connected to independent radio frequency power supplies. The vacuum chamber is evacuated and argon gas is introduced into it. The radio frequency power supply is started. By controlling the sputtering power of the radio frequency power supply, a reflective coating with continuously changing content is deposited on the substrate surface.

4. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 3, characterized in that, The substrate is cleaned by solvent ultrasonic cleaning or ion source cleaning. The cleaning time for the substrate is 10-30 minutes; After cleaning, place the substrate in an oven to dry. The drying temperature of the oven is 100-150℃.

5. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 3, characterized in that, The substrate rotates at a speed of 10-30 r / min; The heating temperature of the substrate is 400-500℃.

6. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 3, characterized in that, The sputtering power of the RF power supply of the copper target is increased at a constant rate from 30-40W to 50-70W. The sputtering power of the radio frequency power supply of the indium target is increased at a constant rate from 50-60W to 80-90W; The sputtering power of the RF power supply of the gallium target is reduced at a constant rate from 120-130W to 40-60W.

7. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 3, characterized in that, The deposition time for magnetron sputtering is 10-30 minutes.

8. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 3, characterized in that, The vacuum level inside the vacuum chamber is 1×10⁻⁶. -5 -1×10 -3 Pa.

9. The copper indium gallium gradient optical coating for stereoscopic imaging according to claim 3, characterized in that, The purity of the argon gas is above 99.999%; The argon gas flow rate is 20-30 sccm; The argon gas is introduced at a pressure of 0.8-1.2 Pa.

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