Filter optimization approach for a chromatic confocal triangulation sensor

Simplified, a chromatic confocal triangulation CCT sensor encodes different surface heights by different wavelengths. A height is measured by determining the corresponding wavelength of the optical signal. The CCT sensor concept solves this task using a multispectral camera, which is a camera with multiple channels, each characterized by a different optical filter. To measure the wavelength with high precision, these filters need to be optimized. For this purpose a physical model is introduced, which describes the multispectral camera. Based on this model, merit functions are developed that cover two aspects: increased resolution and statistical uniqueness of a measurement. These merit functions can be used in a next step to optimize a set of filters.