The invention relates to the field of biosensing technology, concretely relates to a biological
sensing system based on 45-degree dual drive symmetrical structure photoelastic modulation, and the
system realizes original position, rapid, high precision, high sensitivity, high
repeatability, low cost, and control convenience during measurement process. The
system comprises the following components:detection
laser, a
polarizer, a biochemical reaction tank, a microflow
syringe pump, an adjustable slit, a
photoelastic modulator, a polarization analyzer, a photoelectric
detector, an FPGA control module, and a control computer; the biochemical reaction tank is packaged by semicylindrical mirrors and
silicon wafers at interval with PDMS; a flowing channel and an outputting channel are also constructed, two channels are connected to the microflow
syringe pump, the
photoelastic modulator is a
photoelastic modulator with a 45-degree dual drive symmetrical structure, the structure comprises a dual drive
piezo electric crystal and a photoelastic
crystal which form a 45 degree angle, and the
piezo electric crystal is connected to an FPGA control module by an LC
resonance high voltage control circuit. The product is mainly applied to the aspect of biosensing.