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B a s i c O p t i c s S y s t e m
T e a c h e r ’ s G u i d e
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tual image, viewed through the eyepiece lens, coincides with the virtual image of the grid pattern viewed through
both lenses.
Further study, Increasing Magnification:
As the objective lens is moved closer to the object, the eye-
piece must be moved further away. In practice, the objective can be moved to within about 13 cm before distor-
tion from lens aberrations becomes significant. The theoretical limit is 10 cm, or the focal length of the objective
lens.
When the pencil is illuminated by the point source, the shadow appears sharper than when illuminated by a dis-
tributed light source (the crossed-arrow object). When illuminated by both point sources, the pencil casts two
shadows. The area where the shadows overlap is the umbra. The areas of partial shadow are the penumbra. By
moving the pencil toward the screen, the relative size of the umbra is increased. By moving the pencil away from
the screen, the umbra is decreased until the two shadow separate entirely.
Summary of Contents for OS-8515B
Page 6: ... Basic Optics System About the Experiments 6 ...
Page 26: ... Basic Optics System Experiment 9 Apparent Depth 26 ...
Page 38: ... Basic Optics System Experiment 13 Telescope 38 ...
Page 42: ... Basic Optics System Experiment 14 Microscope 42 ...
Page 44: ... Basic Optics System Experiment 15 Shadows 44 ...
Page 46: ... Basic Optics System Telescope and Microscope Test Pattern 46 ...