Measurement of sperm motility

摘要

A micro-sample of semen is exposed to a beam of light from an inexpensive and small laser device. Light scattered by the sample is detected by a photodetector. The photodetector signal is analyzed in the frequency domain to provide a measure of the amplitude of the signal components having frequencies above about 100 Hz. This measure is representative of the numbers of motile sperm in the sample. A motile/immotile percentage is obtained by dividing the motile measurement by a value representative of the amplitude of the full-frequency photodetector signal. In a preferred embodiment frequency-amplitude analysis is carried out in the time domain using frequency splitting filters and integrating the filtered signals. The light receiving aperture for the photodetector is made annular or part-annular in shape to overcome sample orientation or polarization effects.