The AOTFnC is a special acousto-optic tunable filter called Polychromatic Modulator, which uses the anisotropic interaction inside a tellurium dioxide crystal to control independently or simultaneously different lines from an incoming UV or VISIBLE laser light (White laser, Ar+, Kr+, HeNe, DPSS, Dye...). Up to 8 distinct lines can be mixed and separately modulated in order to generate different colorimetric patterns. The specific crystal cut of the AOTFnC produces good diffraction efficiency (> 90%), narrow resolution (1-2nm), a low cross-talk between lines, and high extinction ratio.
The large separation angle between 0 and 1st orders, as well as the excellent output chromatic colinearity (<0.2mrd ) make this AOTF a powerful tool for free space or fiber pigtailed applications. Its associated thermal stabilisation maintains stable diffraction efficiency and reduces dramatically beam drift with single mode fibre pigtailing. This is a major advantage for high sensitivity applications.