Microarray technology has provided a way to quantitate the simultaneous expression of a large number of genes.As microarray developed towards miniaturization

high throughput and weak signals

it needs high sensitive and addressable detection.Fluorescent detection has been given more and more attention.The very rapid and remarkable development of fluorescence detection will no doubt impact the applications of microarray technology.In generally

fluorescence intensities of microarrays

which reflect the biochemical reaction are detected by a photomultiplier tube or a CCD camera

resulting in the production of digital images.As microarrays are scanned repeatedly for many times

the fluorescent dye will be bleached and the relative intensities of fluorescence probes will decay

which result in the error of microarray analysis. So the mathematical modification on the values of fluorescence intensities is important during microarray processing.An experimental device based the sensitive CCD area imaging and scanning technology is designed for the research on microarray fluorescence photobleaching properties

which is proved to be useful for fluorescence detection of microarray.The microarray consisting of different concentration fluorescence probes is scanned repeatedly in the same condition by this device

and the relative intensities of the same fluorescence probe in different images are extracted orderly by the special software

and then fitted by the nonlinear curves.The results show that the decay of the relative fluorescence intensity can be fitted perfectly by an exponential fitting method.The meanings of parameters in this exponential model are explained.The relations between the parameters of the exponential model and the concentrations of fluorescence probes are also analyzed.The analysis results can be used to modify the data error caused by the photobleaching in microarray technology and to improve the reliability of microarray analysis.