OPTI-502 Optical Design and Instrumentation I John E. Greivenkamp Final Exam In Class Page 1/16 Fall, 2015

Transcription

1 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 1/16 Fall, 2015 Name Closed book; closed notes. Time limit: 120 mintes. An eqation sheet is attached and can be removed. A spare ratrace sheet is also attached. Use the back sides i reqired. Assme thin lenses in air i not speciied. As sal, onl the magnitde o a magniication or magniing power ma be given. I a method o soltion is speciied in the problem, that method mst be sed. Ratraces mst be done on the ratrace orm. Be sre to indicate the initial conditions or or ras. Yo mst show or work and/or method o soltion in order to receive credit or partial credit or or answer. Provide or answers in a neat and orderl ashion. Onl a basic scientiic calclator ma be sed. This calclator mst not have programming or graphing capabilities. An acceptable example is the TI-30 calclator. Each stdent is responsible or obtaining their own calclator. Note: On some qantities, onl the magnitde o the qantit is provided. The proper sign convention mst be applied. Distance Stdents: Please retrn the original exam onl; do not scan/fax/ an additional cop. Yor proctor shold keep a cop o the completed exam. 1) (5 points) A 100 mm ocal length thin lens (in air) in made ot o glass N-LaSF46A. The glass code or this glass is What is the longitdinal chromatic aberration o this lens? Longitdinal Chromatic Aberration = = mm

2 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 2/16 Fall, ) (15 points) A 6x Keplerian telescope is constrcted ot o two thin lenses. The ocal length o the objective lens is 360 mm, and this lens serves as the setem stop. a) Determine the ocal length o the ee lens, the telescope length and the ee relie (the distance between the ee lens and the exit ppil) EYE = mm t = mm ER = mm

3 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 3/16 Fall, 2015 b) The objective lens has a diameter o 50 mm. What is the reqired ee lens diameter or the telescope to have an nvignetted ield o view o +/- 2 degrees in object space? Srace t D 2 = mm

4 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 4/16 Fall, ) (10 points) Consider the ollowing optical sstem comprised o or identical thin lenses o ocal length that are each separated b this same distance. Determine the rear ocal length R o this sstem b sketching ras. No calclations o an tpe are reqired or permitted. R =

5 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 5/16 Fall, ) (20 points) A dobl-telecentric sstem is constrcted ot o two thin lenses in air. The magniication o the sstem is m = An object is located 100 mm to the let o the irst element o the sstem, and its conjgate image is located 25 mm to the right o the second element o the sstem. Determine the sstem laot b providing the ocal lengths o the two lenses, the reqired spacing and the stop position. Contines

6 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 6/16 Fall, = mm 2 = mm t = mm Stop Location:

7 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 7/16 Fall, ) (25 points) A Cassegrain Objective consists o a concave primar mirror and a convex secondar mirror. The sstem stop is located at the primar mirror. The working distance is deined rom the vertex o the primar mirror to the image plane. For the prposes o this problem, assme that the mirrors have zero thickness. The object is at ininit. The maximm image size is +/- 8 mm. The sstem operates at an -nmber o /4. The sstem speciication is (onl the magnitdes o the qantities are provided): R P = 500 mm R s = 125 mm t = 200 mm R S D H R P Image Plane (+/- 8 mm) z t WD Determine the ollowing: - Sstem ocal length and the working distance. - Diameter o the Primar Mirror D P - The location and diameter o the Exit Ppil - The reqired diameter o the Secondar Mirror D S and reqired diameter o the Hole in the Primar Mirror D H the sstem to be nvignetted over the speciied Image Size. - The anglar Field o View o the sstem in Object Space NOTE: This problem is to be worked sing ratrace methods onl. All answers mst be determined directl rom the ras o trace; or example, the FOV mst be determined rom the chie ra. Ratraces mst be done on the ratrace orm. Be sre to clearl label or ras on the ratrace orm. A method o soltion explaining or procedre and calclations mst be provided. Gassian imaging methods ma not be sed or an portion o this problem. Yor answers mst be entered below. Be sre to provide details on the pages that ollow to indicate or method o soltion (how did o get or answer: which ra was sed, analsis o ra data, etc.) Sstem Focal Length = mm Working Distance = mm Primar Mirror Diameter D P = mm Secondar Mirror Diameter D S = mm Diameter o the Primar Mirror Hole D H = mm Exit Ppil: mm to the o the primar mirror vertex. D XP = mm FOV = +/- deg in object space

8 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 8/16 Fall, 2015 Srace C t n t/n n n n n n n Contines

9 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 9/16 Fall, 2015 Provide Method o Soltion This is a reqired portion o the problem: Contines

10 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 10/16 Fall, 2015 Contines

11 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 11/16 Fall, 2015

12 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 12/16 Fall, ) (10 points) An optical sstem is comprised o two thin lenses in air. The irst lens has a ocal length o 100 mm and the second lens has a ocal length o 200 mm. The two lenses are separated b 75 mm. An object is located 200 mm to the let o the irst lens. Determine the image location relative to the second lens and the image magniication. NOTE: Use Gassian Redction and Gassian Imaging or this problem. Cascaded imaging ma not be sed (o ma not image throgh one srace and then se this image as an object or the other srace). Image is located mm to the o the lens. Magniication =

13 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 13/16 Fall, ) (15 points) A 200 mm x 300 mm monochrome monitor is to be viewed at a distance o 0.5 m. The desired image qalit is to be excellent as determined b matching the resoltion o the ee. The image was captred on a 10 mm x 15 mm detector. The camera lens has a ocal length that matches the FOV o a 38 mm lens on a 35 mm camera (the ilm size is 24 x 36 mm). The camera is designed sing the hperocal condition so that objects between 2 m and ininit meet the above image qalit or blr condition. What is the reqired ocal length o the imaging lens? What is the reqired /# or the imaging lens? What is the approximate resoltion o the sstem in pixels (assme the blr size eqals the pixel size)? Blank page ollows

14 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 14/16 Fall, 2015 Resoltion: x pixels = mm /#:

15 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 15/16 Fall, 2015 Spare Ratrace Sheet: Srace C t n t/n n n n n n n

16 OPTI-502 Optical Design and Instrmentation I John E. Greivenkamp Final Exam In Class Page 16/16 Fall, 2015 Spare Ratrace Sheets: Srace C t n t/n n n Srace t

17 OPTI-502 Eqation Sheet OPL nl n sin n sin n1 dt t n t n n d n 1 d n 2 BFD d R FFD d F (n n)c n n z z 1 R n n F E z/n m z/n m n m m n m N F2 2 R1 1 n n 2 z/n mm z/n PN PN F 1 2 R n n k 1 t /# E NA n sin U n DEP 1 1 /# W 1 m/# 2NA 2n I HЖ n n tan( 1/2) 10in 250mm MP MP 1 m MP mrmpk mv mobjmpeye

18 M E L A LA 2 d LO E 2 4( /# ) W Exposre H E T a Un a and a Hal a and a Fll DOF B /# W L H D LH L B NEAR 2 n1 P n d n d2 P P sin MIN / 2 n sin / 2 1 n S C sin n R D2.44 /# D /# in m 2 Sag 2R nd 1 n n n F n C d C P n F n C 1 TA CH rp dc Cd P