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Experimental Study on the Light Output of the Photonic Crystals Fabricated Using Femtosecond Laser

One of the keys to improve PET imaging performance is to improve light output of the detector module [1],[2]. At present, the scintillation crystal used in PET detectors cannot output satisfactory amount of intercepted light because the high refractive index causes the phenomenon of total reflection, which seriously affects the imaging effect. Femtosecond laser is a promising method to process a large number of photonic crystal structures on conventional scintillation crystals to improve light output. The following conclusion can be drawn: (1) Femtosecond laser can be implemented to fabricate photonic crystal. The parameters of the laser may have great impact on the performance of light output. (2) Initial experiment showed that the micro-structure can greatly improve the light output by over 50%. (3) Simulation using Tracepro matched perfectly to the experimental result. Next step is to determine the appropriate process parameters and processing methods. Techniques of processing practical large-scale surface will be studied, too.