We have demonstrated a thermally compensated KTiOPO4(KTP)Q‐switch with a 10 mm × 6 mm clear aperture and high contrast ratio. This device showed excellent resistance to thermal depolarization at average power densities as high as 1 kW/cm2. Capacitive coupling allowed us to operate theQ‐switch for greater than 109shots with no sign of electrochromic damage. ©1995 American Institute of Physics.