The test works by detecting fluorescence.

Scanners that detect fluorescence are routinely used to sort mail and thus can guard against conterfeiting or re-use.

Chlorophyll fluorescence has been revolutionized by the use of modulated chlorophyll fluorometers in which the light source is modulated (rapidly switched on and off) and the detector is tuned to detect only fluorescence excited by the measuring light.

BiFC does not require specialised equipment, as visualisation is possible with an inverted fluorescence microscope that can detect fluorescence in cells.

With it we might be able to detect fluorescence from considerable distances, and record its density on photographic film.

The most impressive items were a lumines- cence-spectrophotometer and a binocular microscope to detect fluorescence.

The beads are run through a flow cell which uses a laser to detect fluorescence.

They range from Plant Science based, which are used extensively to detect, measure and analyse fluorescence from chlorophyll during the photosynthesis process, to general purpose fluorometers tuned to the specific fluorescence properties of target samples.

Within the machine the transducer that detects fluorescence created from the upper beam is located a distance away from the sample and at a 90-degree angle from the incident, upper beam.