in an optical waveguide structure (G02F1/017, take precedence)

Full Title

Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics > for the control of the intensity, phase, polarisation or colour (G02F1/29, G02F1/35 take precedence) > based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction (G02F1/03 takes precedence) > in an optical waveguide structure (G02F1/017, take precedence)