Optical Instruments

1
Optical Instruments
2
The Camera
3
(No Transcript)
4
Shutter speed refers to how long the shutter is
open and the film exposed.
5
f-Stop
f-stop f/D
6
Focusing
- operation of placing the lens at the correct
position relative to the film for the sharpest
image. To focus on nearby objects the lens must
be moved away from the film.
7
(No Transcript)
8
Depth of Field
For a given distance setting, there is a range of
distances over which the circles the confusion
will be small enough that the images will be
reasonably sharp.
9
Conceptual Example Shutter Speed
To improve the depth of field, you stop down your
camera lens by two f-stops from f/4 to f/8. What
should you do to the shutter speed to maintain
the same exposure?
10
The Human Eye
11
Focusing The Eye
12
(No Transcript)
13
Astigmatism
14
Farsighted Eye
A particular farsighted person has a near point
of 100 cm. Reading glasses must have what lens
power so that this person can read a newspaper at
a distance of 25 cm? Assume that the lens is very
close to the eye.
15
(No Transcript)