The invention relates to a double light path high-efficiency
fluorescence collecting
system which mainly comprises a slit plate, an IP plate, two
optical fiber rows, a light screen, a
photomultiplier tube (PMT), a
light filter, a support and a logarithmic
amplifier. The two ends of the slit plate are fixed on a support platform, and the IP plate is transmitted on the slit plate. The two
optical fiber rows are fixed on the slit plate by the fixing support. The back ends of the two
optical fiber rows are integrated into one bundle which is fixed by a
metal column and is packed into a
metal round cover of the
photomultiplier tube, and the back end faces of the two optical
fiber rows are close to the light screen. The
light filter is arranged behind the light screen, the PMT is arranged behind the
light filter, the output of the PMT is connected with the logarithmic
amplifier, and the PMT
metal round cover is fixed on a
machine frame through the support. The double light path high-efficiency
fluorescence collecting
system has the advantages of simplified light path
layout, convenient adjustment, reduction in cost and improvement in
fluorescence collecting efficiency; the fluorescence collecting efficiency of the invention is more than 50 percent higher than that of the prior structure; the
quantum detection efficiency of a CR reading
system is improved.