Acousto-Optic Frequency Shifters

Wavelength 415-1550 nm; Type Visible, IR; Operating Frequency 40-200 MHz; Active Aperture 1.5-6 mm; Optical Material Tellurium Dioxide

Transmission through an acousto-optic (AO) device causes the input light to experience a frequency shift equal to the RF drive frequency. The acousto-optic frequency shifters (AOFS) from Gooch & Housego (G&H) are optimized for the needs of applications like interferometry, with the ability to achieve high extinction ratio between modes.

The product line includes standard products with frequency shifts of over 300 MHz and integrated low-power AOFS modules in which the RF driver has been built into the housing. Frequency shifters for specific application, including frequency shifts up to 600 MHz, can be customized on request. The frequency shifters are manufactured using high quality tellurium dioxide (TeO2), grown and polished in-house, for lowest insertion loss and excellent power handling. Standard AOFS products are offered for wavelengths in the visible and NIR for use with fundamental and doubled Argon Ion, Nd:YAG, He:Ne, diode, dye, and Ti:Sapphire lasers. With standard frequency shifts of over 300 MHz and custom frequency shifts up to 600 MHz, as well as models for double-pass configurations, the frequency shifters match most research and industrial needs.

Frequency shifters are highly efficient acousto-optic devices, requiring very low drive power to achieve the desired frequency shift. G&H’s AOFS designs typically use the slow shear mode, resulting in slow rise time, but requiring minimal power consumption (typically < 100 mW power draw). This allows to often package the driver with the AOFS for a compact and power-efficient solution.

Applications: Interferometry; Laser Cooling; Laser Doppler Velocimetry; Laser Doppler Vibrometry (LDV); Optical Heterodyne Detection