SPECTRALLY VARIABLE SOURCE BASED ON SPATIAL CONTROL OF WHITE-LIGHT BEAM (PP20, 374-377)

We experimentally demonstrate the concept of the spectrally variable source whose spectral distribution can be controlled via spatial transmission pattern. We built a proto-type setup consisting of a super-continuum white-light source, a Powell lens for generation of the lineshape beam, a spatially variable spectral filter for the wavelength-to-position transition, and a transmissive LCD display as the computer-assisted spatial light modulator. The experimental results show the control of spectral distribution in a range from 470 nm to 650 nm via 15 spectral channels with a resolution of approximately 15 nm. The results confirm the feasibility of the concept and indicate technical issues for improvement towards a programmable source generating any arbitrary spectral distribution in the whole visible range, which can be a useful tool for colour and vision experiments.