 |
In
this section, we look at some of the properties of ideal lenses and
mirrors. The level is pretty simple throughout; little more
than
basic trigonometry is assumed. None the less some of the
results
get rather complex.
In this section, we're going to assume
that lenses and mirrors form images, and then look at some of the
details of the image formation. Elsewhere, we proved that
parabolic mirrors bring light to a focus.
A proof that a parabolic lens brings light to a focus would be a
bit more complex, as lenses are not quite so simple as mirrors, but
geometrically very similar. In no case do we attempt to prove
that parabolic mirrors or lenses actually form perfect images -- as, in
fact, they don't. We discuss this in a little more detail when we consider ideal lenses and mirrors.
| A
discussion of what we mean by an "ideal" lens or mirror, along with
some notes on how they differ from real lenses and mirrors. |
Ideal
Lenses and Mirrors |
| A discussion of
images formed by lenses and mirrors: whether they're real or
virtual, how large they are, and where they're formed. | Lens and Mirror Images | | We
determine the brightness of the image formed in a simple camera.
This result is needed for some other things we'll do later. | Camera Image
Brightness | | It's
impossible to build a telescope, pair of binoculars, or other optical
instrument out of simple mirrors and lenses which makes extended
objects appear brighter. In other words, nebulae will always appear dim when viewed through an ordinary telescope. | Visual
Image Brightness |
Page created on 9/23/07. Updated on 9/26/07. |
