Three-channel High-precision Optical Detecting Instrument Based on FPGA

In order to detect weak optical signals quickly and precisely,a three-channel high-precision optical detecting instrument based on FPGA was designed.The system uses a very sensitive photomultiplier tube to be the sensor,transform the strength of light to digital pulse signal,then catch the frequency of the pulse which could reflect the strength of the optical signal.Inside the FPGA,a NIOS II soft core was configured to be the central control,μC/OS-II operating system was transplanted to control the key module,LCD,step motor and so on.The system has three channels which could detect three different kinds of reagent,the interference among the three channels was little,the consistency and the system noise was low,greatly improve the detection efficiency.In the real experiment,the instrument was quite sensitive,the linear response was good and the detecting time was short,so it could be an efficient tool in the rapid detection.