Fosforoskoop koosneb kahest pöörlevast kettast, mille sees on augud, mis on paigutatud igale kettale võrdsete nurkade vahedega ja konstantse kaugusega keskpunktist, kuid ühes kettas olevad augud ei ühti teise ketta aukudega.
Hea teada
Fosforestsentsi mõõtmisel asetatakse kahe ketta vahele fosforestseeruva materjali proov, kusjuures ühes kettas oleva augu kaudu sisse tulev valgus ergastab fosforestseeruvat materjali, mis seejärel kiirgab valgust lühikeseks ajaks, seejärel kettaid pööratakse ja nende kiirust muutes saab mõõta materjali hõõgumise aja.
A phosphoroscope consists of two rotating disks with holes in them. The holes are arranged on each disk at equal angular intervals and a constant distance from the centre, but the holes in one disk do not align with the holes in the other.
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A sample of phosphorescent material is placed in between the two disks. Light coming in through a hole in one of the discs excites the phosphorescent material which then emits light for a short amount of time. The disks are then rotated and by changing their speed, the length of time the material glows can be determined.