18, rue Nicolas Appert 91400 Orsay - France

Polychromatic modulators

The AOTFnC is a special acousto-optic tunable filter which uses the anisotropic interaction inside a Tellurium dioxide crystal (TeO2) 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 (1-2 nm), 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 (<0.2 to <0.3 mrd ) make this AOTF a powerful tool for free space or fibre pigtailed applications. Its associated thermal stabilization maintains stable diffraction efficiency and reduces dramatically beam drift with single mode fibre pigtailing. This is a major advantage for high sensitivity applications.

 

Additional information

AOTFnC*HR7MR7LR7VISCPChIRAssociated RF drivers
Number of channels / Lines842881
Acoustic velocity (nom)660 m/s660 m/s660 m/s675 m/s640 m/s
Optical wavelength range400-650 nm400-650 nm400-650 nm450-700 nm400-650 nm700-1000 nm
Transmission> 90 %> 90 %> 90 %> 95 %> 90 %> 95 %
AO interaction typeBirefringentBirefringentBirefringentBirefringentBirefringentBirefringent
Selected order-1-1-1-1-11
Input Light polarizationLinear orthogonalLinear orthogonalLinear orthogonalLinear orthogonalLinear orthogonalLinear parallel
Output Light polarizationLinear parallelLinear parallelLinear parallelLinear parallelLinear parallelLinear orthogonal
Drive frequency range74-158 MHz74-158 MHz74-158 MHz80-153 MHz52-111 MHz37-62 MHz
Active aperture3 x 3 mm²3.5 x 3.5 mm²3 x 3 mm²3 x 3 mm²2.5 x 2.5 mm²2.5 x 2.5 mm²
Spectral resolution (FWHM)nom 1-4 nmnom 2-8 nmnom 4-16 nm< 1.5 nmnom 1.6-7.6 nmnom 5-11 nm
Separation angle (orders 0-1)> 4°> 4°> 4°> 4.6°> 3°> 3.5°
Chromatic colinearity (order 1)< 0,3 mrd< 0,3 mrd< 0,3 mrd< 0,2 mrd< 0.3 mrd< 0.2 mrd
Temperature stabilizationTNTNTNTNTNTN
AO Efficiency>=90% /line>= 90 % /line>= 90 % /line>= 90 % /line>= 90% /line>= 85% /line
Rise time1 µs / mm1 µs / mm1 µs / mm1 µs / mm1 µs / mm1 µs / mm
Max accepted RF power< 0.15 W /line< 0.3 W /line< 0.5 W /line< 0.1 W /line< 0.15 W /line< 1 W /line
Electrical impedance50 Ohms50 ohms50 ohms50 ohms50 ohms50 ohms
VSWR< 2/1< 2/1< 2/1< 2/1< 2/1< 2/1
Size70 x 36,6 x 35,8 mm370 x 36,6 x 35,8 mm370 x 36,6 x 35,8 mm370 x 36,6 x 35,8 mm370 x 36,6 x 35,8 mm370 x 36,6 x 35,8 mm3
Operating temperature10 to 40 °C10 to 40 °C10 to 40 °C10 to 40 °C10 to 40 °C10 to 40 °C