elementary optical concepts - the university of...
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![Page 1: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/1.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
Inverted imageObject
Elementary Optical ConceptsA Simple Camera
f
ab
Thin lens formula: 1/f = (1/a) + (1/b)
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and PupilsThe exit pupil is an image of the entrance pupil formed by the eyepiece lens.
Basic layout of a Keplerian telescope.
![Page 2: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/2.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
Inverted imageObject
Elementary Optical ConceptsA Simple Camera
f
ab
Thin lens formula: 1/f = (1/a) + (1/b)
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and PupilsThe exit pupil is an image of the entrance pupil formed by the eyepiece lens.
Basic layout of a Keplerian telescope.
![Page 3: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/3.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and PupilsThe exit pupil is an image of the entrance pupil formed by the eyepiece lens.
Basic layout of the Keplerian telescope.
![Page 4: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/4.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
![Page 5: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/5.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
Telescope magni�cation
![Page 6: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/6.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and Pupils
![Page 7: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/7.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
Inverted imageObject
Elementary Optical ConceptsA Simple Camera
f
ab
Thin lens formula: 1/f = (1/a) + (1/b)
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
The eye is an integral part of the “telescope system”
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and PupilsThe exit pupil is an image of the entrance pupil formed by the eyepiece lens.
Basic layout of a Keplerian telescope.
![Page 8: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/8.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
Inverted imageObject
Elementary Optical ConceptsA Simple Camera
f
ab
Thin lens formula: 1/f = (1/a) + (1/b)
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
The eye is an integral part of the “telescope system”
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and PupilsThe exit pupil is an image of the entrance pupil formed by the eyepiece lens.
Basic layout of a Keplerian telescope.
![Page 9: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/9.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
Entrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
Collimated light: light rays from individual image points are parallel.
![Page 10: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/10.jpg)
Objective lensEyepiece lens
Image
Elementary Optical ConceptsA Simple Keplerian Telescope
Inverted imageObject
Elementary Optical ConceptsA Simple Camera
f
ab
Thin lens formula: 1/f = (1/a) + (1/b)
O�-axis light raysEntrance pupil
Exit pupil
Field plane(or image plane)
Pupil diameter = D/Mag
(Diameter = D)
feyepiece fobjective
Telescopes magnify angles
Mag = fobj/feye
The eye is an integral part of the “telescope system”
Collimated light: light rays from individual image points are parallel.
Telescope magni�cationFields and PupilsThe exit pupil is an image of the entrance pupil formed by the eyepiece lens.
Basic layout of a Keplerian telescope.
![Page 11: Elementary Optical Concepts - The University of Chicagoastro.uchicago.edu/yerkes/docs/AstronomerTalks/AlHarper-Elementary... · Eyepiece lens Objective lens Image Elementary Optical](https://reader030.vdocuments.mx/reader030/viewer/2022020316/5b26a22c7f8b9af4578b4f8e/html5/thumbnails/11.jpg)
“Night glasses” and “richest -!eld’ telescopes
• If the exit pupil of a telescope is bigger than about 7mm, all the lightwon’t enter our dark-adapted eye
• A “rich-field” telescope has just the right focal length eyepiece lens togive us all the light we can use and no more
• The objective lenses of 7x50 binoculars are just the right size to giveus all the light we can use from a seven-power telescope
• Questions– What is the magnification of the telescope in our example?– What’s the “richest-field” objective lens diameter for our telescope?– Why might we want to use a higher power eyepiece, even if it gives us an
exit pupil smaller than 7 mm?– What power eyepiece would give us “richest field” performance with an
8-inch diameter telescope with a focal length of 40 inches?– What would be the focal length of a “rich field” eyepiece for our 8-inch,
f/5 telescope?– Why wouldn’t we want binoculars with larger diameter objective lenses
than 50 mm?