TechSpecs

BPI^® Spectrometers utilize a spectrometer chip (micro spectrometer mounted on a linear CCD detector array) to produce a survey type spectrometer with a resolution of about 10nm. The ‘entrance slit’ is a 300 micrometer optical fiber. The reflection grating has 625 lines/mm with a blaze wavelength of 560nm. The dispersion is 0.12nm/micrometer. The wavelength reproducibility is about 0.1nm. The ‘exit slit’ is a 256 pixel linear photodiode array. The visible light source is a high temperature incandescent bulb. The UV source is a phosphor broadened mercury vapor tube.

The units can also determine if colored lenses meet EC standards for traffic signal safety as outlined in ISO 14889, ISO DIS 8980-3 and ISO 13666.5 Filter Level LED's are located on the left of the instrument.
One LED comes on and stays on. This indicates the filter level that the lens has achieved. (There is no violation of the safety standards).
Flashing LED. As the main display cycles through the colors as they are being analyzed, a LED may change from being steadily lit to flashing. This indicates a safety standard violation. The LED will start to flash as the main display reaches the color that is out of range. As the main display reaches the end of its cycle, the LED stops flashing. It will resume flashing as it reaches the out of range color during subsequent cycles.
NO LED's illuminated. No LED will be lit if the ratio of UV to visible light is too great to meet the standard.