SPHERICAL
ABERRATION - LENS WITH VARIABLE DIAPHRAGM
APPARATUS
object
light source
113-01-C1
plano-convex
lens with V-shaped slot
101-17-B
ground
glass screen
113-01-A
optical
bench
113-01-D
camera
202-09-D
DESCRIPTION
The mask has a V-shaped slot behind
a vertical slot that together provide two apertures at equal distances
above and below the central axis. The V-shaped slot moves
laterally so that the aperture-axis distance is continuously
variable. With the apertures near the central axis and the plane
side of the lens facing the source, focus the image of the light source
on the ground glass screen. As you increase of the aperture
distance, it is necessary to move the screen further away to locate the
point where the two rays converge.
