Method for determining an aging condition for an optical waveguide grating and temperature sensor

• US 6,504,962 B2
• Filed: 07/23/2001
• Issued: 01/07/2003
• Est. Priority Date: 05/01/1997
• Status: Expired due to Fees

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Inoue, Akira, Ishikawa, Shinji, Shigehara, Masakazu, Iwashima, Toru, Harumoto, Michiko
• Primary Examiner(s): SIKDER, MOHAMMAD YUNUS
• Application Number:
  US09/909,897
• Publication Number:
  US 20020009281A1
• Time in Patent Office: 533 Days
• Field of Search: 385/12, 385/13, 385/37, 385/123, 385/124, 359/566, 359/570, 65/171, 65/291.8, 653/84, 654/25
• US Class Current: 385/12
• CPC Class Codes: G02B 6/02185 based on treating the fibre, e.g. post-manufacture treatment, thermal aging, annealing annealing glass fibres C03B37/15

Abstract

The present invention provides a method for determining a condition of aging for an optical waveguide grating. In this method, the aged deterioration,curve of the optical waveguide grating is set as a forms of C·t^−α, t represents time, and α and C represent parameters. Then, the condition of the aging is determined based on the aged deterioration curve.

Claims

1. A temperature sensor having an operating temperature range, guaranteed operating time and temperature resolution, said temperature sensor comprising an optical waveguide with a grating as a sensing section, said grating having been subjected to accelerated aging under a predetermined condition, the condition being determined to provide a displacement of a measured temperature value due to aged deterioration of the grating that is no greater than the temperature resolution when the sensor is used for the guaranteed operating time at the maximum temperature in the operating temperature range.

2. The temperature sensor according to claim 1, wherein said waveguide has the surface subjected to etching after the accelerated aging.

3. The temperature sensor according to claim 1, wherein said waveguide has a heat-resisting coating as its surface.