aberration
(types of flaws in telescope images)
In optics, aberration is an optical system's deviation
from true, such as points in the image being smeared and/or shapes being
changed. Lenses and mirrors inevitably cause some aberration
which can be the primary limit to a telescope's use.
They come from a variety of causes resulting in a variety
of symptoms. Some classes:
The term aberration has other uses in astronomy that
are not related to optics, i.e., better optics would not help:
- astronomical aberration (sometimes just called aberration), is the apparent difference in position in the celestial sphere of a celestial body (e.g., star) due to the motion of the observer. Given the orbit of the Earth around the Sun, light received from a particular star is approaching us at a slightly different angle because both we and the light are moving. This factor is sufficiently significant (several arcseconds) that it must be taken into account in determining accurate and precise coordinates for a celestial object, and is especially need in astrometry and in the determination of orbits of solar system bodies.
- relativistic aberration further effects due to the speed of light due to relativity including relativistic beaming.
(telescopes,optics)
Further reading:
http://en.wikipedia.org/wiki/Optical_aberration
http://www.telescope-optics.net/aberrations.htm
Referenced by pages:
astigmatism
barrel distortion
chromatic aberration
convolution
Dall-Kirkham telescope
distortion
deformable mirror (DM)
field curvature
focal plane
focal plane tilt
Herschelian telescope
image stabilization
Korsch telescope
coma
pointing error (PE)
pincushion distortion
Ritchey-Chrétien telescope (RCT)
refracting telescope
Schiefspiegler
Schmidt camera
speckles
spherical aberration
Strehl ratio
three-mirror anastigmat
wavefront error (WFE)
Index