Dielectric microfilter arrays for multispectral measuring devices

For specified colour measuring devices miniaturized dielectric filter arrays have been designed and developed. The manufacturing procedure is based on combination of coating- and micropatterning process including the employment of etchstop layers. The spectral properties of basic filter, fabricated as an unpatterned filter blank, have been modified within small areas by Reactive Ion Etching (RIE) a defined number of layers. This way dielectric interference filters with two different spectral characteristics have been arranged edge by edge within a period of 15 mu m. In this paper design and development of two-colour microfilter arrays are described and problems are depicted, arising with the production of multicolour dielectric microfilters. An alternative manufacturing procedure is discussed, making it possible to arrange more than two different interference filters edge by edge.