Tunable optical filter changer Lambda VF™ series

Sutter Instrument has developed several filter changers specially designed for wavelength selection over a wide spectral range to any given nanometer value. The Lambda VF-5™, Lambda VF-10, Lambda VF-1™ and Lambda VF-1 Edge™ employ the innovative VersaChrome® and VersaChrome Edge™ thin-film filter technology from Semrock® to provide outstanding bandpass characteristics such as high transmission (close to 100%), steep edges and out of band blocking. These tunable filter systems produce the center wavelength you select on command. And since these filters pass an image, they are equally suitable for emission and excitation paths. How It Works A specific wavelength within the wide spectral range of each filter is obtained by adjusting the angle of incidence from 0 to 60 degrees. This tuning causes little or no change in spectral performance of the filter regardless of the state of polarization of the light passing through the filter. The current VersaChrome series has 15 filters covering 338 to 900nm. By simply selecting the desired center-wavelength on the controller, users can select any combination of filters for the Lambda VF-5 (which holds up to 5 filters), any single filter in the series for the Lambda VF-1 or any one of 10 filters in the VF-10 that uses smaller filters suitable for laser applications. The latest development from Semrock® is the VersaChrome Edge filter technology that allows selection of the band-width as well as the center wavelength. This new filter system uses separate tunable high-pass and low -pass filters in series to define the bandpass. An additional filter is used in series with these filters to provide the best blocking outside the pass-band.