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Chapter 6 - Optical Telescopes - Coggle Diagram
Chapter 6 - Optical Telescopes
telescope optics
refraction
Snell's law
reflection
law of reflection
collecting light
the larger a telescope mirror or lens, the more light it collects.
light gathering power(LGP)
the ratio of the collected light
the ratio of time used to collect light
focal length, image scale and focal ratio
focal point: the point where parallel light rays focus
focal length: distance from center of objective to focal point
plate/image scale: how many arches sky fall on each pixel
focal ratio: focal length divided by diameter
surface brightness and image brightness
image size: h = θf
image brightness
LGP divided by the image area
inversely proportional to the square of focal ratio
limiting magnitude: M_{L} = 2.7 + 5logd
angular resolution
Airy disk
Rayleigh criterion: smallest resolvable detail
Dawes limit: smaller than Rayleigh criterion
types of telescope
refractors
classical cassegrain
Gregorian
reflectors
compound
schmidt camera
schmidt-cassegrain
aberrations
deviations from the ideal diffraction patterns
chromatic aberration
dispersion
monochromatic aberration
spherical
coma
astigmatism
distortion
filed curvature
vignetting
telescope mounts
equatorial
polar axis
declination axis
alt-az
foci
prime focus
nasmyth focus
coude focus
eyepieces
magnification: ratio of focal length
eye relief: distance between eyepiece and exit pupil
other visual accessories
eyepiece accessories
barlow lens
erecting lens
star diagonal
finder
crosswire or reticles
field of view
true field of view
apparent died of view
concepts
focal ratio:焦比
aberration：像差
chromatic aberration：色差
monochromatic aberration：单色像差
astigmatism：像散
distortion：畸变
exit pupil：出射光瞳
eye relief：适瞳距
star diagonal：天顶镜
erecting lens：正像棱镜
finder：寻星镜
crosswire/reticle：十字丝