Optical waveguides – With optical coupler – Particular coupling structure
Patent
1991-12-02
1993-04-13
Ullah, Akm E.
Optical waveguides
With optical coupler
Particular coupling structure
G02B 610, G02B 600, G02F 100
Patent
active
052029417
ABSTRACT:
Polarization independent switch or coupler including a directional coupler with extremely relaxed fabrication tolerances. The coupler includes a mono-crystalline wafer of electro-optic material with two closely adjacent light waveguides at an upper surface along with electrodes positioned adjacent the waveguides. The electrodes include a grounded, main electrode formed on one side of the waveguides and four smaller electrodes formed in a line on a side or sides of the waveguides opposite to the main electrode, each of the four smaller electrodes being supplied with a voltage. The electrodes and waveguides can be in a planar or stacked relationship to one another. When the voltages applied to the middle two electrodes have equal values and have like polarity (V.sub.c =V.sub.b) and the voltages applied to the outer electrodes have equal values and like polarity (V.sub.d =V.sub.a), the light travelling in one waveguide is barred from transferring to another waveguide.
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Telefonaktiebolaget L M Ericsson
Ullah Akm E.
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