Radial polarization converter S-waveplate is the most common available space-variant waveplate.
Higher order S-waveplate is similar to ordinary – converts linear polarization to radial or azimuthal polarization. However, this product can generate higher topological charge optical vortices. Fabrication of higher order S-waveplate is based on the inscription of self-organized nanogratings inside fused silica glass using a femtosecond laser.
Referring to LIDT measurements at fs regime (full report) and ns regime (full report), we’ve observed our S-waveplates have laser irradiation resistance similar to uncoated fused silica substrates. LIDT value measured at 1064 nm, ~10 ns is 63,4 J/cm² and it is not dropping while increasing exposure time. It proves, our waveplates are very high performance and suitable for high power laser applications.
Examples of fast axis patterns for 2nd (left), 3rd (center), and 4th (right) order S-Waveplates (measured with Hinds Instruments Exicor MicroImager).