Optical coating materials

An optical coating involves the plating of one (or several) metallic or dielectric films on the surface to an optical component. It is intended to increase or reduce the reflectivity, beam separations, color separations, and polarization of the light. The most widely used coating methods include vacuum-coating and electronicless coating. Principle of optocoating: Vacuum coating: Vacuum coatings are coatings which require higher vacuum. It is made from the plated metal and then electroplated. You can place the substrate in the same space as your target. The evaporation coating is usually the target of heating so that the surface components evaporate in the form of free radicals or ions and are deposited on the surface of the substrate by film-forming method (scattering island structure-trapezoidal structure-layered growth). Sputtered coating It’s easy to see how the sputtered layer is formed. A characteristic of an optical film is its smooth surface. An interface between the layers of the film layer is also geometrically segmented. Although the film’s refractiveindex can jump at that interface, it remains continuous throughout the film. Medium for absorption: It may be normal uniformed or non-uniform. It is more challenging to use the film in practical applications than the ideal film. Because its optical properties and physical properties are different from that of bulk material and because it has rough interfaces, diffuse scattering results. A diffusion interface is created by mutual penetration between films. The film exhibits anisotromy due to its growth, structure, stress and time effects. The following are common optical coating materials. 1. Metal (alloy): germanium, chromium, aluminum, silver, gold, etc. Germanium. A rare metal which is not toxic and nonradioactive. It is used mostly in the semiconductor and plastic industries. The light transmission range for this metal is from 2000NM to 4000NM. Chrome. Colloid is used sometimes in spectroscopes, and used to enhance adhesion. A colloid layer might be as low as 550NM. Under the guidance of aluminum mirror, however, 30NM can provide effective adhesion. Aluminium. It exhibits the best ultraviolet reflection performance, surpassing all other common metals. Additionally, the effective thickness of this film exceeds 50NM. Silver. When the evaporation is rapid enough and the substrate temperatures are not too high, silver can be as reflective as aluminum. This happens because of the large accumulations at low speed, which lead to higher absorption. Gold. This material has the highest reflection among all materials. 2. Oxides. Yttrium trioxide. With electron gun Evaporation, properties vary according to the film thickness. It is 8% at 500nm. It is very common as an aluminum protective layer, especially with the large incident angle between 800-12000nm. Cerium dioxide. Cerium dioxide is evaporated by high-density (tungsten boat) evaporation at 200°C. Its refractive int is about 2.2. You can obtain low-absorption thin nylon films in the 500nm range by using oxygen ion plating. titania. The refractive indice is defined as the distance between light and dark at 2.21500nm. High refractive Index and relative firmness make this material popular among people for their anti-reflection and splitter film applications. Silicon dioxide. The crystal is transparent and colorless, has high melting points, is hard, and exhibits good chemical stability. The crystal’s purity is excellent, and it can be used for Si02 coatings. It can be separated into visible, infrared or ultraviolet light depending on its intended use. You will see pores in the film, and it will become fragile. On the other hand, films with too much pressure will absorb the water, and the refractive indice will go up. Zirconium dioxide. White heavy crystals have high levels of refractive indices and resistance to heat, chemical properties that are stable and very pure. There are several reasons to use this crystal. It is used for the preparation of high quality zirconia coated without breaking point. It will diffuse the incident sunlight and decrease the light transmittance. Some incident light sources, such as those that emit high frequencies of radiation from the sun, will be affected by the optical rotation. For example, the material that absorbs light in red will look green. But these issues of poor processing are easily removed. Hafnium oxide. After it has evaporated at 150C with an electron gun, the refractive indice is around 2.0C. An oxygen-ion assisted plating technique can give stable refractive values of 2.5-2.1. For the protection of the aluminum outer layer in the range of 8000-12000NM, HFO2 is more effective than SiO2. 3. Fluoride. Magnesium fluoride. An antireflective material with a thickness of 4 waves, it’s widely used in glass optical films. Calcium fluoride & bariumfluoride. Their weakness is their inability to compact completely. A lack of complete compactness is their limitation. They cannot currently be used for infrared-based films because the transmittance shifts toward longer wavelengths at high temperature. Lead fluoride. It’s a UV-resistant material with high refractive index. It is best to use it at 300nm because it has a low refractive factor when in direct contact with tantalum (molybdenum), molybdenum (tungsten) and other materials. 4. You may also be interested in other compounds. Zinc sulfide. With a refractive index from 2.35400-13000m, the light transmission range is good for environmental durability and has high stress. Mainly used for decorative, spectroscopic, cold light and infrared film. Lead telluride. This type of IR material has a high refractive. This thin film material can be transparent for 300 to 4000NM. Sublimated is the method of sublimating the material in the far-infrared. A substrate temperature of 250C can be beneficial. This is a good way to protect your health. It is effective when 40000NM of it is present. There are many other materials that can be used with the infrared edge of 14000NM. Silicon dioxide Price The supply and need in the market, market trends and economic activity all have an impact on the price. To get a quote on the latest SiO2 cost send us an email. (brad@ihpa.net) Silicon dioxide Supplier Luoyang Tongrun Nano Technology Co. Ltd. We export our goods worldwide. Send an inquiry if you need high-quality SiO2 dust. (brad@ihpa.net)
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