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Method of controlling polarization properties of a photo-induced device in an optical waveguide and method of investigating structure of an optical waveguide

Assignee: Furukawa Electric North America Inc
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Filing: 1994-02-17
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Granted: 1996-09-24
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Expires: 2014-02-17
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Abstract

Abstract A method of controlling the polarization properties of a photo-induced device in an optical waveguide and a method of investigating the structure of a light guiding body such as an optical waveguide are disclosed. A device, such as gratings, is written by exposing one side of the optical waveguide to light. The unexposed side is then exposed to an amount of light sufficient to impart the desired birefringence to the written device. The birefringence can be minimized in the written device by exposing the opposite side to light in an amount sufficient to minimize the amount of birefringence. The light guiding body is investigated by cleaving the elongated light guiding body, such as an optical waveguide, to expose its cross-section. The cleaved section is then treated to expose difference between the core and cladding. Treatment may include etching in an acid or base. The cross-section is then profiled with a scanning probe microscope such as an atomic force microscope to investigate the structure of the light guiding body. The difference in refractive index can be determined across the cleaved endface based on differences in the etched depth.

Inventors

  • 👤 Daryl Inniss
  • 👤 Ashish M. Vengsarkar
  • 👤 Qian Zhong

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-10 01:36
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; G02B6/02057; G02B6/02076; G02B6/0208; G02B6/021; G02B6/02109; B; B82; B82Y; B82Y15/00; G02B21/00; G02B21/0004; G02B21/002; G02B6/10; G02B6/105; G02B6/02123; G02B6/02152

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 62 words
A method of controlling polarization properties of a photo-induced device in an optical fiber comprising the steps of writing the device by exposing one side of the optical fiber to light while leaving another side unexposed, and then exposing the previously unexposed side to light in an amount sufficient to symmetrize the refractive index change about the optical axis of the fiber.
Claim 2
Independent Claim 62 words
A method of controlling polarization properties of a photo-induced device in an optical fiber comprising the steps of writing the device by exposing one side of the optical fiber to light while leaving another side unexposed, and then exposing the previously unexposed side to light in an amount sufficient to symmetrize the refractive index change about the optical axis of the fiber.
Claim 3
Dependent Claim 14 words
The method according to claim 1 wherein one or several unexposed sides are exposed.
Claim 4
Dependent Claim 35 words
The method according to claim 1 including the step of minimizing birefringence in the written device by exposing several sides to light in an amount sufficient to minimize the amount of birefringence in the device.
Claim 5
Dependent Claim 14 words
The method according to claim 1 wherein the light source is an ultraviolet source.
Claim 6
Dependent Claim 14 words
The method according to claim 1 wherein the light source is an infrared source.
Claim 7
Dependent Claim 15 words
The method according to claim 1 wherein the optical fiber has a germanium doped core.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-09-24 2000-03-25 2000-09-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-09-24 2004-03-25 2004-09-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-09-24 2008-03-25 2008-09-24 $7700.00 Window Closed / Lapsed

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