Overview
The fundamental purpose of optics is to control light in a manner to make it functional, optical coatings play a big role to enhance that optical control and the performance for your optical system by modifying the reflectance, transmittance, and absorptive properties of the optic substrates to make them much more efficient and functional. Paralight Optics' optical coating department provides our customers throughout the world state-of-the-art in-house coatings, our full-scale facility allows us to produce large number of custom-coated optics to suit a variety of customer needs.
Features
Coating Capabilities
Paralight Optics' state-of-the-art, in-house, optical coating department provides our customers worldwide with coating capabilities ranging from metallic mirror coatings, diamond-like carton coatings, anti-reflection (AR) coatings, to an even wider range of custom optical coatings in our internal coating facilities. We have extensive coating capabilities and expertise in both designing and producing coatings for applications throughout the ultraviolet (UV), visible (VIS), and infrared (IR) spectral regions. All optics are meticulously cleaned, coated, and inspected in a class 1000 clean room environment, and subjected to the environmental, thermal, and durability requirements specified by our customers.
Coating Design
Coating materials are combination of thin lays of metals, oxides, rare earth, or diamond-like carton coatings, the performance of an optical coating depends on the number of layers, their thickness, and the refractive index difference between them, and the optical properties of the substrate.
Paralight Optics has a selection of thin film modeling tools to design, characterize, and optimize many aspects of an individual coating's performance. Our engineers has the experience and expertise to assist you at the design stage of your product, we use software packages such as TFCalc & Optilayer to design coating, your ultimate production volume, performance requirements and cost needs are considered to assemble a total supply solution for your application. Developing a stable coating process takes several weeks, spectrophotometer or spectrometer is used to check that the coating run meets the specifications.
There are several pertinent pieces of information that need to be relayed in the specification of optical coating, the essential information would be substrate type, wavelength or the range of wavelength of interest, transmission or reflection requirements, angle of incidence, the range of angle of incidence, polarization requirements, clear apertures, and other supplemental requirements such as environmental durability requirements, laser damage requirements, witness sample requirements, and other special requirements of marking and packaging. These information should become consideration to ensure the finished optics will fully meet your specifications. Once the coating formula has been finalized, it is ready to be applied to optics as a part of the production process.
Equipment of Coating Production
Paralight Optics has six coating chambers, we have the capability to coat very high volumes of optics. Our state-of-the-art optical coating facilities including:
Ion-Beam Assisted Deposition (IAD) uses the same thermal & E-beam method to evaporate coating materials but with the addition of an ion source to promote nucleation and growth of materials at lower temperatures (20 - 100 °C). The ion source allows temperature-sensitive substrates to be coated. This process also results in a denser coating that is less sensitive to spectral shifting in both humid and dry environmental conditions.
Our Ion Beam Sputtering (IBS) deposition chamber is the most recent addition to our line-up of coating tools. This process uses a high energy, radio frequency, plasma source to sputter coating materials and deposit them on substrates while another RF ion source (Assist source) provides IAD function during deposition. The sputtering mechanism can be characterized as momentum transfer between ionized gas molecules from the ion source and the atoms of the target material. This is analogous to a cue ball breaking a rack of billiard balls, only on a molecular scale and with several more balls in play.
● Advantages of IBS
★ Better Process Control
★ Wider Selection of Coating Designs
★ Improved Surface Quality and Less Scatter
★ Reduced Spectral Shifting
★ Thicker Coating in a Single Cycle
We utilize E-Beam and thermal evaporation with ion assist. Thermal & Electron Beam (E-Beam) deposition uses a resistive heat load source or an electron beam source to evaporate a selection of materials such as transition metal oxides (e.g., TiO2, Ta2O5, HfO2, Nb2O5, ZrO2), metal halides (MgF2, YF3), or SiO2 in a high vacuum chamber. This type of process must be done at elevated temperatures (200 - 250 °C) to achieve good adhesion to the substrate and acceptable material properties in the final coating.
Paralight Optics has long history of Diamond-like carbon (DLC) coatings exhibiting hardness and resistance to stress and corrosion similar to natural diamonds, making them ideal for harsh environments. DLC coatings provide high transmission in the infrared (IR) such as Germanium, Silicon and a small friction coefficient, which improves wear resistance and lubricity. They are constructed from nano-composite carbon and are often used in defense applications and other systems exposed to potential scratches, stress, and contamination. Our DLC coatings are compliant with all military durability testing standards.
Metrology
Paralight Optics employs a range of testing to ensure the specified performance of custom optical coatings and meet your application needs. Coating metrology equipment contains:
✔ Spectrophtometers
✔ Microscopes
✔ Thin Film Analyzer
✔ ZYGO Surface Roughness Metrology
✔ White Light Interferometer for GDD measurements
✔ Automated Abrasion Tester for Durability
