For use in anti-Stokes Raman applications, Semrock Inc. has unveiled patent-pending short-wave-pass thin-film filters that are an addition to the company’s RazorEdge family of steep-edge filters. Designed to attenuate a designated laser line by six orders of magnitude, they maintain a typical edge steepness of 0.5% of the laser wavelength to measure small Raman shifts. RazorEdge technology produces >93% average signal transmission to detect weak signals, and the filters display a laser damage threshold of 1 J/cm2 at 532 nm. Transition width is <186 cm–1. Rejected light is reflected for convenient alignment and good stray-light control. The filters are fabricated by ion-beam sputtering.