Photoelastically induced light modulation in gradient index lenses

Abstract

A new photoelastic light modulator is demonstrated based on the modulation of the birefringence and of the index profile in graded index lenses. Using the birefringence modulation we obtained 35% modulation depth in a quarter-pitch lens and 65% using a half pitch lens at acoustic frequencies up to the MHz range. Using the index profile modulation in a half-pitch lens as a fibre-to-fibre connector we obtained 15% modulation without the incorporation of any polarizer