发明申请
- 专利标题: Optical Sensors
- 专利标题(中): 光学传感器
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申请号: US11572125申请日: 2005-07-07
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公开(公告)号: US20080043242A1公开(公告)日: 2008-02-21
- 发明人: Gregory Emmerson , Corin Barry Gawith , Peter Smith
- 申请人: Gregory Emmerson , Corin Barry Gawith , Peter Smith
- 优先权: GB0415882.0 20040715
- 国际申请: PCT/GB05/02682 WO 20050707
- 主分类号: G01B9/02
- IPC分类号: G01B9/02
摘要:
An optical sensor comprises a sensing element comprising a waveguide grating with a response that varies with an effective modal index experienced by light propagating in the grating and a sample window for receiving fluid which affects the effective modal index to modify the response, the sensing element arranged to receive light from a light source and to output the light after filtering; and an analysing element comprising a second waveguide grating having a second response, and arranged to receive light output by the sensing element and to output the light after filtering for detection by an optical power detector. The combination of the two gratings converts changes in the wavelength of light output by the sensing element in response to the sample of fluid to changes in the amount of light, allowing the fluid index to be deduced from a measurement of optical power. The two elements may be fabricated on a single substrate to reduce errors from environmental disturbances such as temperature changes.