Method for detecting time-resolved fluorescence based on principle of phase balanced frequency multiplication modulation

摘要

The present invention relates to a method for detecting time-resolved fluorescence based on a principle of phase balanced frequency multiplication modulation. A stimulating light source modulated by using a baseband signal acts on a to-be-measured target to trigger fluorescence, so that the fluorescence intensifies and decays periodically; then, a frequency-doubled square signal is used to control a sampling period and divide an ascending period of the fluorescence into two and a decay period of the fluorescence into two; after independent sampling is performed separately, sampling differences of the two parts are separately calculated and then added to obtain an intensity representative value of a fluorescence signal and to obtain a concentration value of the to-be-measured target. The method in the present invention can not only likewise cancel fluorescence interference of a substrate in a sample, but also can cancel ambient bias light, power-frequency interference of a spatial electromagnetic wave or other signals, and therefore improves signal intensity in fluorescence measurement on the detection sample, has an advantage that cannot be accomplished in a conventional time-resolved fluorescence method, and can be applied in fluorescence intensity detection of a target in fields such as biology, chemistry, and medicine.