|
Because of the heat-resistant difference between the cancer cell and the normal cell, the normal cell can resistant higher
temperature than cancer cell does. Clinical experiments showed that microwave or ultrasonic can effectively cure cancer.
But since there is strong electromagnetic interference, the conventional temperature sensor will find itself hard to get the
accurate temperature. So it is necessary to find a feasible sensor to measure the temperature. Fiber optic grating (FBG)
sensor is excellent candidate for measuring temperature of in vivo lesion. In this paper, the investigation on the
application of an optical fiber sensor in the field of biomedical engineering was introduced. The main objective of our
investigation has been to develop a novel senor based on FBG to measure the temperature of in vivo lesion. Based on the
Bragg equation, the temperature sensing properties of fiber optic grating was studied and the affection of central
wavelength on the FBG sensing sensitivities have also been analyzed. In order to reduce the error of the FBG sensors
system, it is necessary to adopt a good demodulation algorithm to calculate peak wavelength. An experimental system
was set up which to test feasibility of the sensor. Among some of the peak detection algorithms, tested by experimental
measuring system, the peak detection method by the Gaussian nonlinear curve fitting was finally adopted and the test
results showed that the temperature measuring system based on the FBG was in the accuracy of 0.1°C.
|
