whenever light passes from one medium to another medium with different optical properties,most notably refractive index,part of the light is reflected and part of the light is transmitted(refracted). The intensity ratio of the reflected and refracted components is a function of the difference in refractive index among the materials,the polarization of the incident light and the qngle incidence.
According to Fresnel's law it is convenient to think of incident ra-diation as the superposition of two plane polarized beams,p-pplasrized which electric field parallel to plane of incidence and s-polarized which electric field perpendicular to the plane of incidence . Fresnel's laws can be summarized the following two equations.
When reflected and refracted rays are perpendicular to each other (θ1+ θ2=90°),the reflected light is completely s-polarized. This angle is calld Brewster's angle.Optical coatings are used to alter the reflectance,transmittance,absorbance,or polarizing properties of optical components.The optic being coated is call the substrate.The coating is deposited in high vacum using the process of evaporation by either e-beam,resistive heat or IAD(Ion assisted Deposition) in conjunction with an e-beam source..We can also offer coating done with an APS(Advanced Plasma Source) by Leybold .This technique combines the advantages of IAD coating and ion plating without some of the drawbacks associated with ion plating.We can offer state-of-the-art equipment,advanced design software and highly experieced engineers to provide you with absoluterly the highest level of support.Coating materials include metals(Au,Al,Ag) ,dielectrics(Oxides,Fluorides) . |
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The standard coating following :
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Coating Type |
Properties and Application |
| Antireflection |
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Applied to materials with refractive indices from 1.45 to 2.4.The most popular antireflection coating for visible. They are insensitive to change in incidence angles. |
Multilayer “V” |
Used to provide low reflectance with in a narrow durable wavelength band for most laser application. Minimum reflection can be less than 0.1% |
Broadband Multilayer |
These coatings have excellent performance over a broad spectral range broadband. Coating performance is sensitive to angle of incidence. |
Dual Wavelength Band |
Offer very low reflectance at two widely spaced wavelengths, such as Nd:YAG Laser (1064) and its second harmonic (532) . Lasertec makes this a double wavelength waveplate. |
| Partial Reflection |
Narrow Band |
Provide 50% reflection and transmission at an angle of 45qincidence for a single wavelength. Perfect for beamsplitters application. Transmission/reflection (T/R) ratio of 20/80, or othersfor Beamsplitter is available upon request |
Broadband |
Over a wide bandwidth provides 50% reflection and transmission.Lasertec can also provide coatings with different R/T ratios at and specific angle of incident. |
| Beamsplitter |
Laser Line Polarization Beamsplitter |
High reflection for s-polarized and antireflection for p-polarized for laser application. |
Broadband Polarization Beamsplitter |
Wide wavelength bandwidth provide high reflection to s-polarized and antiflection to p-polarized |
Dichroic Beamsplitters Mirrors |
These coatings can separate the laser fundamental and the pumpwavelength, or the fundamental and the second harmonic. They are specific applied to laser mirror. |
| DPSSLaser |
diode pumped laser optics coating (DPO) |
These coatings are designed for a diode pumped laser. They can be deposited on a variety of substrates and have high damage threshold. |
| High Reflection |
Dielectric High Reflective Coatings |
Provide high reflectance over a broad bandwidth, and is ideal for a tunable laser or in white light applications. |
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Metallic High Reflective Coatings |
Metallic coatings have low peak reflectance, mechanical durability and damage threshold, but they have extremely broadband and low cost. They are insensitivity to angle of incident light and polarization. |
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