BANDPASS FILTER FOR LIGHT HAVING VARIABLE LOWER AND UPPER CUT-OFF WAVELENGTHS

摘要

A bandpass filter for light has variable lower and upper cut-off wavelengths. The bandpass filter comprises an areal long-pass filter defining the variable lower cut-off wavelength and an areal short-pass filter defining the variable upper cut-off wavelength. The long-pass filter has different lower cut-off wavelengths in different first area regions which follow to one another in a first direction, and the short-pass filter has different upper cut-off wavelengths in different second area regions which follow to one another in a second direction. The long-pass filter and the short-pass filter are connected in series and spatially fixed relative to one another. The first direction and the second direction are oriented crosswise to one another.