Wavelength selective optical switching devices

• US 9,025,094 B2
• Filed: 07/13/2012
• Issued: 05/05/2015
• Est. Priority Date: 11/08/2011
• Status: Active Grant

• Current Assignee: Santec Holdings Corp.
• Original Assignee: Santec Incorporated
• Inventors: Sakurai, Yasuki
• Primary Examiner(s): NGO, HUYEN LE
• Application Number:
  US13/548,401
• Publication Number:
  US 20130128215A1
• Time in Patent Office: 1,026 Days
• Field of Search: 349/18, 349/196, 359/356
• US Class Current: 349/18
• CPC Class Codes: G02B 6/35 having switching means by changing the optical properties of the medium G02F1/00
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon

Abstract

A wavelength selective switch device includes an incidence part where wavelength multiplexed light made of light of a plurality of wavelengths enters, an exit part that includes a plurality of fiber that outputs light of a wavelength selected from a signal in which wavelength multiplexed light that entered from the incidence part enters, a polarization diversity part that separates incidence light that entered the incidence part according to polarization components of the incidence light to make first and second optical beams, a wavelength dispersion and synthesis element that spatially disperses incidence light according to a wavelength of the incidence light and multiplexes the spatially dispersed reflected light according to the wavelength, and a wavelength dispersion and synthesis element that spatially disperses incidence light according to a wavelength of the incidence light and multiplexes the spatially dispersed reflected light according to the wavelength.

Claims

1. A wavelength selective switch device, comprising:

an incidence part where input wavelength multiplexed light comprising a plurality of wavelengths enters along an input direction;

an exit part comprising a plurality of fibers that outputs, along an output direction, output wavelength multiplexed light comprising selected wavelengths from the plurality of wavelengths;

a polarization diversity part that;

separates the input wavelength multiplexed light travelling along the input direction according to polarization components to make a first and a second optical beam; and

synthesizes a third and a fourth optical beam both having the selected wavelengths and travelling along the output direction by aligning a polarization direction of one of the third and the fourth optical beam with the other of the third and the fourth optical beam to generate the output wavelength multiplexed light comprising the selected wavelengths;

a wavelength dispersion and synthesis element that;

spatially disperses the first and second optical beams travelling along the input direction according to the plurality of wavelengths to generate spatially dispersed light travelling along the input direction; and

wavelength multiplexes spatially dispersed and wavelength selected light travelling along the output direction to generate the third and the fourth optical beams;

a condensing element that condenses the spatially dispersed light travelling along the input direction onto a two-dimensional liquid crystal beam deflection element;

the two dimensional liquid crystal beam deflection element comprising a plurality of pixels arrayed in a lattice on an xy plane, with an x-axis direction defining a wavelength dispersion direction, and wherein changes in refractive index characteristics of the pixels changes a phase of the plurality of pixels along the y axis direction, and changes the output direction of each wavelength of the spatially dispersed light to generate the direction;

a liquid crystal beam deflection element drive part that changes the refractive index characteristics of the pixels by driving an electrode of each pixel; and

an image height adjusting medium (IHAM) disposed at a position to receive either the third or the fourth optical beam, such that one of the third or the fourth optical beam passes through the IHAM and the other of the third or the fourth optical beam does not pass through the IHAM, and the IHAM adjusts an image height of the third or the fourth beam that passes through the IHAM to match an image height of the third or fourth optical beam that does not pass through the IHAM, wherein the image height is defined to be a height of the optical beams relative to the plurality of optical fibers of the exit part.

2. The wavelength selective switch device according to claim 1, wherein

the liquid crystal beam deflection element is a LCOS element having a multiplicity of pixels arrayed two-dimensionally, and

the liquid crystal beam deflection element drive part controls the voltage applied to each pixel according to wavelength selection characteristics.

3. The wavelength selective switch device according to claim 1, wherein

the liquid crystal beam deflection element is a liquid crystal element having a multiplicity of pixels arrayed two-dimensionally, and

the liquid crystal beam deflection element drive part controls the voltage applied to each pixel according to wavelength selection characteristics.

4. The wavelength selective switch device according to claim 1, wherein

the polarization diversity part includes:

a polarizing beam splitter that separates the input wavelength multiplexed light into the first and second optical beams, and

a wavelength plate that aligns the polarization direction of one of the third and the fourth optical beam with the other of the third and the fourth optical beam.

5. The wavelength selective switch device according to claim 1, wherein the image height adjusting medium is a meniscus lens.

6. A method of switching wavelength multiplexed light comprising a plurality of wavelengths using a wavelength selective switch device, the method comprising:

receiving, by a polarization diversity part, the wavelength multiplexed light;

separating, by the polarization diversity part and according to polarization components, the wavelength multiplexed light to generate a first and a second optical beam;

spatially dispersing, by a wavelength dispersion and synthesis element, the first and second optical beams to generate spatially dispersed light;

condensing, by a condensing element, the spatially dispersed light onto a two-dimensional liquid crystal beam deflection element,

wherein the liquid crystal beam deflection element comprises a plurality of pixels that when driven change the reflected output direction of each wavelength of spatially dispersed light to generate spatially dispersed and wavelength selected light comprising wavelengths selected from the plurality of wavelengths;

multiplexing, by the wavelength dispersion and synthesis element, the spatially dispersed and wavelength selected light to generate a third and a fourth optical beam both having the selected wavelengths;

passing one of the third or the fourth optical beam through an image height adjusting medium (IHAM) to adjust an image height of the one of the third or fourth optical beam to match an image height of the third or the fourth optical beam that did not pass through the image height adjusting medium, wherein the image height is defined to be a height of the optical beams relative to a plurality of optical fibers of an exit part of the wavelength selective switch device;

synthesizing, by the polarization diversity part, the third and the fourth optical beams by aligning a polarization direction of one of the third or the fourth optical beam with the other of the third or the fourth optical beam to generate output wavelength multiplexed light; and

coupling the output wavelength multiplexed light into a fiber from the plurality of optical fibers of the exit part.

7. The method according to claim 6, wherein

the liquid crystal beam deflection element is a LCOS element having a multiplicity of pixels arrayed two-dimensionally, and

the liquid crystal beam deflection element drive part controls the voltage applied to each pixel according to wavelength selection characteristics.

8. The method according to claim 6, wherein

the liquid crystal beam deflection element is a liquid crystal element having a multiplicity of pixels arrayed two-dimensionally, and

the liquid crystal beam deflection element drive part controls the voltage applied to each pixel according to wavelength selection characteristics.

9. The method according to claim 6, wherein

the polarization diversity part includes:

a polarizing beam splitter that separates the input wavelength multiplexed light into the first and second optical beams, and

a wavelength plate that aligns a polarization direction of one of the third and the fourth optical beam with the other of the third and the fourth optical beam having the selected wavelengths.

10. The method according to claim 6, wherein the image height adjusting medium is a meniscus lens.