PURPOSE: Model the optics of an astronomical telescope.
DESCRIPTION: The lens at the left produces parallel light, as from a star. The second lens is the telescope objective, and the lens at the right is the eyepiece. The parallel beam of rays entering the objective lens is wider than that emerging from the eyepiece, indicating the ability of the telescope to "gather" light. When the position of the "star" is changed by moving the source up, the image is moved down and the angle at which it is viewed (inverted) is magnified relative to the incoming light, indicating the ability of the telescope to produce angular separation of the stars it is viewing.
Choice of slit baffle and distance of baffle from source determine the number of rays and their spacing.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Optical board with slit baffle and accessory lenses.
SETUP TIME: None.
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