Jason Michael Alexander

57871027, Jul 28, 1998

Nov 20, 1996

8/754217

Jason I. Alexander - Foster City CA
Walter R. Bosenberg - Sunnyvale CA
Richard W. Wallace - Los Altos CA

Lightwave Electronics Corporation - Mountain View CA

H01S 310
G02F 135
G02B 600

372 22

A non-linear optical device in which quasi-phase matching between different optical waves of differing polarizations and refractive indices increases the interaction length between the waves. The quasi-phase matching structure includes a periodic structure over which the non-linear coefficient varies with a given period, preferably the sign of the non-linear coefficient being inverted between two alternating regions. In LiNbO. sub. 3, the periodic structure can be achieved by electrical poling. The required period length is increased by selecting light waves of different polarizations for the non-linear interaction such that a large portion of the dispersion between the waves of different wavelength is compensated by the birefringence of the waves of different polarization. In particular, periodic poling can quasi-phase match radiation in the range of 0. 80. mu. m to 1. 2. mu. m to generate second harmonic generation radiation in the blue and green visible spectrum.