Temperature-compensated fibre optic strain gauge

US7796844B2 · kind B2 · utility

Assignees

• The Hong Kong Polytechnic University · CN
• Mass Transit Railway Corporation Limited · CN

Inventors

• Hwa Ywa Tam · Kowloon, CN
• Siu Lau Ho · Kowloon, CN
• Shun Yee Liu · Kowloon, CN
• Kang Kuen Lee · Kowloon, CN
• Tony Kar Yun Lee · Kowloon, CN
• Chun Cheong Hon · Kowloon, CN
• Hing Keung Chan · Kowloon, CN
• Aiken Yiu Ming Tam · Kowloon, CN

Key dates

• Filing date: Jul 22, 2008
• Grant date: Sep 14, 2010
• Expiry date: Nov 14, 2028

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/02204
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A temperature-compensated fibet optic strain gauge (10) for measuring strain of a host structure (5), the strain gauge (10) comprising: a mount (20) having a void (19) separating a first section (17) from a second section (18); a first fiber Bragg grating (FBG) (30); a second fiber Bragg grating (FBG) (40); and removable bridging portions (24) adjacent to the void (19) to connect the first section (17) to the second section (18), the bridging portions (24) being removed after the mount (20) is operatively attached to the host structure (5); wherein a right-side failure proof feature is provided by detecting whether a reflection wavelength reverts to an original Bragg wavelength of the first FBG (40) to indicate whether the first FBG (40) has broken.