Picosecond Time-correlated Single Photon Counting Spectrometer Data Acquisition System Development,

Time correlated single photo counting(TCSPC) is a precise means that was used in measuring the high-speed and dim light signal, it is fittable especially for the measurement of fluorescent lifetime and time resolved spectrum in ps, ns and us interval. Now is applied broadly in scientific field such as physics, chemistry, biology, material research and information science. This paper is mainly about designing a data acquisition subsystem for the picosecond TCSPC spectrometer, a new acquisition stucture based on PCI bus is proposed and the feasible project is showed in details. In this paper, the principle and framework of picosecond TCSPC spectrometer are introduced firstly, and the relative progress of other confrere is mentioned too. Aimed at improving the shortcomings of the original system, a mended acquisition structure is proposed to replace the multi channel analyzer and the performance of two designs is contrasted. Then author take apart the realization of data acquisition subsystem into two chapters, software development and hardware design. In the chapter about hardware, PCI bus architecture is analyzed in the begining, the functional elements of data acquisition are partitioned based on good comprehension on the PCI bus protocol and application of bridge chip subsequently, then the functional elements are designed respectively according to the system's requirements, while using dual port RAM as local bus buffers and FPGA as control unit, so much for the hardware design. In the side of software development, kernel of Windows 2000, mode of WDM driver and tools for developing and debugging a WDM driver are introduced, then how to develop a driver through DriverStudio is illustrated and the practical driver code on how to deal with special problem such as interrupt is listed. At last, user application is programmed by VC++, using MFC and relative Win32 API as tools. User application provides a interface between operator and machine, with it, client can control data acquisition process. Finally, some measures are further put forward to improve the reliability and stability according to the request of system. All of these make favorable effect true. This design has been put into use in practice. It is certain that the performance indexes of this data acquisition system have completely accorded with the design requiremenst of picosecond TCSPC spectrometer.