Sill Optics is now offering an f-theta scan lens, model S4FLT2500/328, which can accommodate multi kW high power lasers. This is the first 30mm aperture high power lens made of fused silica with low absorption anti-reflection coatings to dramatically reduce internal absorption in the bulk material and the coating. This minimises thermal shift within the lens. Thermal shift can lead to changes in spot size and energy density which leads to unstable process conditions.
The S4LFT2500/328 has a focal length of 500mm, optimised for wavelength 1064nm, but usable from 1,030nm to 1,090nm, a maximum scan field size of 280 x 280mm and can accommodate up to a 30mm input beam diameter. The performance of the lens is well suited to image single mode fiber or disc lasers with Gaussian intensity profiles of M²=1.X.