Study on signal-to-noise ratio of drug-fluorescence imaging system

The quantity value of signal and background light of fluorescence imaging system of nasopharyngeal carcinoma is calculated when photosensitizer is excited by the light at the wavelength of 488nm.In order to distinguish the signal from the background light,the light-transmission coefficient of a narrow-band filter must be as great as possible and noise must be reduced by a factor of 4.3×10-5.According to the absorption characteristic of colored glass,the ratio of signal transmission coefficient to background light transmission becomes large with optical-path increased suitably.If the thickness of the colored glass and the band width of the narrow-band filter now on hand is encreased properly,fine signal-to-noise ratio and resolving capability of fluorescence imaging can be obtained.