Laser power stabilization using a double prism attenuator

An electro-opto-mechanical device based on frustrated total internal reflection is designed and constructed for use in the laser beam power control. It is based on a double prism attenuator and it demonstrates high dynamic range continuous attenuation up to 120 dB. The device is used to actively stabilize the power of a laser beam over a bandwidth of more than 1 kHz. An enhancement of more than one order of magnitude in the power spectral density of the power fluctuations is obtained in closed-loop operation. • Seamless, 110 dB laser beam piezo-based attenuator of glass prisms, in visible range. • Response speed of the attenuator/shutter shorter than 1 ms. • More than 10 dB noise reduction, to 0.04% laser power fluctuations over few seconds.