Bragg grating chemical sensor with hydrogel as sensitive element

• 作 者: 刘小梅 郑史烈 章献民 丛军 陈抗生 徐坚
• 机 构: Department of Information and Electronic Engineering,Department of Information and Electronic Engine
• 出 处: Chinese Optics Letters
• 发表日期: 2004年12期
• 关键词: chemical sensor polyacrylamide hydrogel fiber Bragg grating sensing mechanism hy

A novel fiber Bragg grating (FBG) based chemical sensor using hydrogel, a swellable polymer, as sensitive element is demonstrated. The sensing mechanism relies on the shift of Bragg wavelength due to the stress resulted from volume change of sensitive swellable hydrogel responding to the change of external environment. A polyacrylamide hydrogel fiber grating chemical sensor is made, and the experiments on its sensitivity to the salinity are performed. The sensitivity is low due to the less stress from the shrinking or swelling of hdrogels. Reducing the cross diameter of the grating through etching with hydrofluoric acid can greatly improve the sensitivity of the sensor.

A novel fiber Bragg grating (FBG) based chemical sensor using hydrogel, a swellable polymer, as sensitive element is demonstrated. The sensing mechanism relies on the shift of Bragg wavelength due to the stress induced from volume change of sensitive swellable hydrogel responding to the change of external environment. A polyacrylamide hydrogel fiber grating chemical sensor is made, and the experiments on its sensitivity to the salinity are performed. The sensitivity is low due to the less stress from the shrinking or swelling of hdrogels. Reducing the cross diameter of the grating through etching with hydrofluoric acid can substantially improve the sensitivity of the sensor.