Polarization beam splitter-polarization rotator structure

• US 8,238,697 B2
• Filed: 04/19/2010
• Issued: 08/07/2012
• Est. Priority Date: 09/08/2005
• Status: Active Grant

• Current Assignee: Infinera Corp.
• Original Assignee: Infinera Corp.
• Inventors: Little, Brent E., Chen, Wei
• Primary Examiner(s): Kianni, K. Cyrus
• Application Number:
  US12/762,495
• Publication Number:
  US 20100202724A1
• Time in Patent Office: 841 Days
• Field of Search: 385/5, 385/28, 385/32
• US Class Current: 385/5
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G02B 6/1228 Tapered waveguides, e.g. integrated spot-size transformers for coupling with fibres G02B6/305
• CPC Class Codes: G02B 6/126 using polarisation effects G02B6/1226 takes precedence
• CPC Class Codes: G02B 6/136 by etching
• CPC Class Codes: G02B 6/272 comprising polarisation means for beam splitting and combining
• CPC Class Codes: G02B 6/2766 Manipulating the plane of polarisation from one input polarisation to another output polarisation, e.g. polarisation rotators, linear to circular polarisation converters
• CPC Class Codes: G02B 6/2773 Polarisation splitting or combining

Abstract

A polarization beam splitter-polarization rotator-polarization beam combiner optical structure comprising a pair of polarization rotators having a polarization beam splitter associated with the input ends of the two polarization rotators, and a polarization beam combiner associated with output ends of the two polarization rotators, and a method of purifying a light signal comprising TE and TM modes by disassociating the primary TE and TM modes from first order splitter and rotation error components.

Claims

1. An optical structure, comprising:

a polarization beam splitter comprising an input end, and an output end having a first output and a second output;

a polarization rotator system comprising a first polarization rotator having an input end and an output end, and a second polarization rotator having an input end and an output end; and

a polarization beam combiner comprising an input end having first and second inputs, and an output end; and

a first optical path including the first output of the polarization beam splitter, the input end of the first polarization rotator, the output end of the first polarization rotator, and the first input of the polarization beam combiner, the first optical path being configured such that first light propagates along the first optical path from the first output of the polarization beam splitter to the first input of the polarization beam combiner through the first polarization rotator; and

a second optical path including the second output of the polarization beam splitter, the input end of the second polarization rotator, the output end of the second polarization rotator, and the second input of the polarization beam combiner, the second optical path being configured such that second light propagates along the second optical path from the second output of the polarization beam splitter to the second input of the polarization beam combiner through the second polarization rotator, wherein the first polarization rotator is spaced from the second optical path and the second polarization rotator is spaced from the first optical path.

2. The optical structure of claim 1 comprising at least one additional optical element.

3. The optical structure of claim 2 wherein the at least one additional optical element is a filter, polarizer, waveguide, reflector, coupler, interconnect, phase modulator, intensity modulator, frequency shifter transducer, oscillator, power splitter, resonator or photodetector.