PURPOSE: Individual observation of floaters in the eye.

DESCRIPTION: Each spool has opaque material across both ends with a pinhole in each center. Viewing a distant light through the pinholes with the spool very close to your eye produces a nearly parallel light beam through your eye onto your retina. Red blood cells located directly in front of your retina diffract this parallel light, causing dark circle diffraction patterns on the retina.

These red blood cells sometimes cause floaters to appear in your eye when you stare into space, for example at the pure blue sky.

SUGGESTIONS:

REFERENCES: (PIRA unknown.) Compare with diffraction of laser light M2-02: LASER DIFFRACTION - OPAQUE DISCS

EQUIPMENT: Spools with end covers with pinholes.

SETUP TIME: None.