substrate-free grid optics
Neutral Density Filters
LASNIX neutral density filters are precision components to reduce laser beam power. All other beam parameters stay unaffected.
The filters are designed for simple alignment and ease of use.
The attenuation principle is based on proprietary free-standing metal grid technology introduced by LASNIX in 1984. Originally developed for high-power CO2 lasers, these grids have been tailored to accomodate the complete infrared spectrum from 0.7 to 1200 Ám. Remarkably high power handling up to 30 kW c.w. has been achieved.
Since the grids are freely suspended, i.e. have no substrate, they can not deviate or offset the beam - in contrast to usual, substrate-bound optical elements. Dispersion of fs pulses is negligible.
In the neutral density filter, a precision fabricated metal grid diffracts a calibrated percentage of power out of the beam. The rejected power is absorbed in the walls of the water-coolable housing. The attenuated transmitted beam passes undeviated (in diffraction terms this beam represents the zeroth order). The mode structure and other beam properties, including the divergence and M2 parameters are fully preserved, as well as the polarization.