Service Detail from Cascade Optical Corp.
They are designed to operate over narrow part of spectrum with very high efficiency. Our V-Coatings centered at wavelengths starting from 193 nm up to 10.6 µ all have R < 0.1% at the design wavelength. Extra high efficiency V-Coatings with R < 0.03% are also available starting at 248 nm up to 2.1 µ. Plot to the right shows a typical response of the V-Coating centered in the UV part of the spectrum.
Micro-machining, photolithographic systems, and a variety of medical equipment use UV lasers with emissions at 193, 248, and 360 nm. In addition most of these systems require a visible laser for alignment. In most cases optical components of these systems are identical, and systems differ only by the laser wavelengths and AR coatings applied. If 633 nm is visible laser used for alignment and/or targeting then there are three different specs for the coatings of the systems operating at 193, 248, and 360 nm, typically:
1. R < 0.25% @ 193 and R < 1% @ 633 nm
2. R < 0.25% @ 248 and R < 1% @ 633 nm
3. R < 0.25% @ 360 and R < 1% @ 633 nm
Since these UV coatings are very difficult to distinguish visually, parts have to be marked and carefully tracked in the inventory. Multi-band V-coating operating simultaneously at 193, 248, 360 and 633 nm solves this problem and all parts from inventory could be used in any system regardless of the operating wavelength of the laser. Spectral performance of our standard 3-V coating is shown in the plot above. Cascade has in production multi V-Coatings operating over any other part of the spectrum within 193 nm and 10.6 µ range.