Variable Edge-Pass Filters

Variable Edge-pass filters from coherent provide the ability to trim the spectral response of a source or detector by continuous adjustment of the cut-on or cut-off wavelength (COWL). The detector can be used to define one side of the curve while another side can be adjusted by means of this filter to fit the exact bandwidth you need. Alternatively, it is possible to trim the source output in a similar manner.

These filters are deposited on a circular substrate and the edge-pass is varied in a linear fashion over a 330 degree arc around the disc. A central hole permits mounting in a wheel, as with the variable neutral density filters.

A broadband source may be converted to a color source by the use of opposed pairs of these filters. Counter rotation adjusts the bandwidth while coordinated rotation will change the center wavelength.

Coherent Auburn Group, 2303 Lindbergh Street, Auburn CA 95602. Phone: 530-889-5365; Fax: 530-889-5366.