The spectral position of the center wavelength λm of the Narrow passband of VERIL linear variable interference filters changes constantly over the length of the filter. These filters possess the same curve characteristics as the corresponding homogeneous filters. Additional blocking is achieved in some cases by graduated colored glasses (graduated optical filter glass). When linear variable filters with a pre-fitted slit are used, Increasing the slit width widens the passband curve and reduces the maximum transmittance ?max. Slit widths up to 1 mm in the case of VERIL S 60 filters and up to 3 mm in the case of VERIL S 200 and BL 200 have practically no effect on spectral performance. The special method of manufacturing these filters gives rise to slight deviations in dispersion from filter to filter and to deviations in linearity. A calibration curve and a calibration table are included with each linear variable filter ordered.

Information provided by SCHOTT.