Solid-state subnanosecond light switch

The design and realisation of a reliable and simple subnanosecond electro-optic light switch is given. This switch is suitable for controlling a mode-locked laser, or for use as a light shutter where nanosecond or subnanosecond response is necessary. The direct-current and pulse responses of the longitudinal zcut XH2PO4 modulator are considered in detail, and an optimum design established using KD2PO4 with ring electrodes. The pulse-forming network employed incorporates several novel features, to produce an overall jitter time of less than 1 ns for a wavefront of 1¿4.3kV and a risetime of 0.65ns.