A Lucas cell is a type of scintillation counter. In contrast to a scintillation counter the light production is instantaneous. See scintillator and scintillation counter for practical applications. Radioactivity is usually measured in these procedures using a scintillation counter. The plastic scintillation counter delivers fast rising edge with varying heights. Low levels may be reported in counts per minute using a scintillation counter. The Wilson chamber represented a primitive scintillation counter which could measure radioactivity. It used a scintillation counter to detect hard x-rays emitted by the Sun.