Passive Integrated Optic Mixer Providing Quadrature Outputs

Abstract

The principle of an integrated optic component providing four optical signals in quadrature is presented. Such an interferometric element has been fabricated by ion -exchange in glass. The effect of various parameters on the quadrature condition have been studied: length of the mixing section, temperature, polarisation. Losses have been characterised. A possible use of this device is illustrated.

Optical multi-mode interference devices based on self-imaging: principles and applications

“…This situation is analogous to the focal shift from paraxial rays prediction due to aberration in optical systems of finite aperture. However, some balancing of the phase errors-and thus an improvement of the imaging quality-is possible by a slight correction of the imaging lengths predicted by (24), (33), and (37), 1351.…”

“…Optical N-way splitters can in principle be realized on the basis of the general N-fold imaging at lengths given by (24). However, by exciting only the even symmetric modes, l-to-N beam splitters can be realized with multimode waveguides four times shorter [33].…”