PURPOSE: Demonstrate phosphorescence.

DESCRIPTION: An ultraviolet light illuminates the face of an oscilloscope tube, causing it to glow a bright green color. When the black light is removed, the tube screen still glows, demonstrating its phosphorescence. This effect is important in avoiding flickering when an oscilloscope, TV set, or computer monitor is viewed.

SUGGESTIONS:

REFERENCES: (PIRA unknown.)

EQUIPMENT: Black light and oscilloscope CRT.

SETUP TIME: None.