Multiple spectral band opto-mechanical modular

摘要

A multiple spectral band opto-mechanical modulator for obtaining simultaneous but independent modulation of an extended IR source in two distinct wavelength bands comprises in one embodiment a first rotating filter wheel having alternating radial segments of transparent and short wavepass filter material, a second rotating filter wheel having alternating radial segments of transparent and long wavepass filter material, a stationary wheel having alternating radial transparent and opaque segments positioned intermediate the first and second rotating wheels and means for rotating said first and second filter wheels at predetermined frequencies.