Frequency-modulated single-mode laser
Three frequency-modulated single-mode lasers employing long multicavity resonators are presented. The f.m. is achieved by simultaneous changes of the length of the additional cavities in such a way that resonance conditions are preserved, and the resonator Q factor remains constant. The linear electro-optic Pockels effect in KDP crystals is used to change the optical length of the additional cavities.