PURPOSE: To show pincushion and barrel distortion.
DESCRIPTION: The optical system in the photograph includes the following: bright point source with condenser lens, ground glass screen, coarse mesh object, first iris, 8 cm focal length lens, second iris, and distant screen. Closing the first iris (preceding the lens) causes barrel distortion, while closing the second iris (following the lens) produces pincushion distortion.
This is not a bright display, but can be seen in a large room and is closest to the theoretical description of distortion.
REFERENCES: (PIRA 6A65.30)
EQUIPMENT: Bright point source with condenser lens, ground glass screen, coarse mesh, iris, 8 cm focal length lens, and second iris.
SETUP TIME: 5 min.
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