Decide the concentration of the systematic pigment known absorbance of in vivo making use of the attenuation property of dispersion electric Osamu emission manner and the device

摘要

PURPOSE: To enable to convert obtained data to data expressing the density of an absorptive coloring matter with known absorptive properties, by generating a short light pulse to transmit objective tissue and detecting moved photons to determine the attenuation rate of photons. CONSTITUTION: At first, signals of 2MHZ are supplied to a mode lock circuit 9 to produce a short light pulse through a NaYAG laser 10 and LDL 20. Next, signals of 4MHZ are injected into the output of YAG laser and then supplied to LDL. The light pulse passes through an inputted light guide and is guided from a subject 30 to an output light guide 24 and a detector 26 jointed with the light guide is connected to a photomultiplier 40 for amplifying detected light. The output of the photomultiplier 40 is next supplied to a constant part of an identification device 50 of a photon counting system to identify the pulse amplitude, and then signals are supplied to a time-amplitude converter 60 to generate an output pulse of an amplitude proportional to the time difference of a starting pulse and a stopping pulse and to convert the pulse by a multi-channel analyzer 70 and a computer 80 into a signal or data set suitable for a display to display the set on a logarithmic display 90.