Fiber-optic voltage sensor based on a Bi12TiO20 crystal

A fiber-optic voltage sensor based on the longitudinal Pockels effect in a Bi12TiO20 crystal is described. The use of a special backreflecting prism a s a phase-retarding element is shown to improve the sensitivity and tempera ture stability of the sensor. A comparison between the temperature properti es of the glass backreflecting prism and that of a quarter-wave plate is de rived. The sensor demonstrates temperature stability of +/-1.5% from -20 de grees C to 60 degrees C and sensitivity of 0.145% per 1 V-max at 850 nm wit hout the use of an additional temperature control channel. (C) 2000 Optical Society of America OCIS codes: 060.2370, 230.2090, 230.5440, 260.1440.