The pulseSelect is an acousto-optical single pulse selector developed for the special demands of femtosecond laser technology. Pulse distortion is minimized by a low dispersive design and the use of reflective optics.  The use of an acousto-optical selection element allows for high repetition rates and high contrast ratio. The pulse repetition rate can be reduced by using an adjustable internal frequency divider or by external triggering. With the pulseSelect low division ratios down to fREP/2 are possible. It has an integrated RF power limitation and protection circuit to prevent modulator damage. For highest stability the phase of the RF carrier frequency is locked to the repetition rate of the laser that is used with. Besides the standard version suited for fs or ps mode-locked Ti:Sapphire lasers, custom wavelength ranges in the VIS are available. For improved contrast ratio of above 6000:1 A·P·E offers the double stage version pulseSelect DUAL (seriell) and for selecting pulses from two synchronized laser sources simultaneously the pulseSelect DUAL parallel.