The Gooch & Housego Acousto-Optic standing wave Mode Lockers can obtain near theoretical mode locked laser pulse widths. The exceptional performance is due to the design and manufacture of the high Q acoustic resonator with very low spurious modes. The Mode Lockers can be used for the Nd:YAG, Nd:YLF, Ti:Sapphire and Argon Ion lasers. The Gooch & Housego, Mode Locker Driver controls the temperature of the acoustic resonator with a closed loop temperature controller in order to control the resonant frequency of the acoustic resonator and maintain the resonance at the precise frequency of the driver's crystal controlled oscillator. The RF drive power is controlled from the front panel. The laser cavity length must be adjusted to match the resonance in order to produce mode locked pulses from the laser. Each Mode Locker system produced (Mode Locker and Driver) is manufactured to match the customer's laser cavity resonator length.