Fluorescence emission model for micro-optic detection system in biochips

In the work, the light source model for the fluorescence emission in the biochips has been extensively studied such as to effectively design the necessary micro-optic elements for the fluorescence signal detection in biochips. With most advantaging properties, the fluorescence technology does provide the high sensitivity, response in real time, and multiple target labeling for the applications in biochips. To practical applications, the final signal detection is to measure the fluorescence emission. In fact, the fluorescence emission process can be determined through four stages of transformation; that is the excitation, the absorption, the fluorescence conversion, and the fluorescence scattering. As the total internal reflection configuration for the fluorescence excitation is utilized, the evanescent waves are introduced from different excitation sources in the viewpoints of the principle analysis and the practical applications, respectively. In such a way, the the spatial intensity of the fluorescence emission is found not to be uniformly distributed, and the performance of the micro-optic detection system thus diversed deviated. Except that, the fluorescence emission is further considered to include the extinction ratio and the quantum yield of the fluorescent dyes and the scattering effect from the molecules in the reaction solution. To the end, the precise fluorescence emission model in the microstructure has been obtained through the above 4 stages by the optic ray-tracing simulation. Accordingly, one corresponding collimating lens has been designed based on the new light source model.