A Preliminary Study on Non-contact and High Resolution Laser Speckle Method for Temperature Detecting
|School||Huazhong University of Science and Technology|
|Keywords||Brownian motion Dynamic Light Scattering Laser Speckle Contrast Imaging High-resolution Temperature distribution measurement|
Temperature measurement is an old subject , but due to the form of heat propagation , and measurement of the complexity and diversity of the objects , on many occasions , the temperature measurement is still a very difficult task . In this paper, the temperature field of non-contact laser speckle sensing method dynamic monitoring of the temperature distribution and variation of the measured object surface can be achieved in the case without scanning , high temporal and spatial resolution in biomedical good prospect of application . Of particles suspended in a liquid in constant Brownian motion , and its speed of movement and the temperature of the liquid , by laser speckle imaging techniques can be used to measure the relative rate of the Brownian movement , and to further obtain the temperature information of the liquid . The key to this method is how to calculate the relative rate of particle movement by laser speckle image . The main content of this paper and the results are as follows : design dynamic light scattering experiments , determined through experiments with a model solution scattering intensity autocorrelation function expressions , further deduced the the laser speckle lining ratio and the relative rate relationship for the measurement of the rate laid theoretical basis. Design experimental verification by the rate of laser speckle contrast image obtained by the Brownian movement of the absolute temperature relationship : a linear relationship between the square of the absolute temperature value of the rate within a certain range , and to prove the feasibility of the temperature measuring method . Using this method to measure the dynamic changes of the temperature of the surface of the model solution , reconstruction of the distribution of temperature field , and the measurement results and the thermocouple measurement results were compared , and shows good spatial and temporal resolution of the present method . Of course , as a new principle of temperature measurement and temperature measurement method , the method also there are many inadequacies , the paper also gives some suggestions for improvement .