US3711184A - Large catadioptric objective - Google Patents

Large catadioptric objective Download PDF

Info

Publication number
US3711184A
US3711184A US00133223A US3711184DA US3711184A US 3711184 A US3711184 A US 3711184A US 00133223 A US00133223 A US 00133223A US 3711184D A US3711184D A US 3711184DA US 3711184 A US3711184 A US 3711184A
Authority
US
United States
Prior art keywords
glass
air
corrector
primary
correctors
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00133223A
Inventor
M Amon
S Rosin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
KOLLSMAN INSTR CORP US
Kollsman Instrument Corp
Original Assignee
Kollsman Instrument Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kollsman Instrument Corp filed Critical Kollsman Instrument Corp
Application granted granted Critical
Publication of US3711184A publication Critical patent/US3711184A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00Systems with reflecting surfaces, with or without refracting elements
    • G02B17/08Catadioptric systems
    • G02B17/0884Catadioptric systems having a pupil corrector
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00Systems with reflecting surfaces, with or without refracting elements
    • G02B17/08Catadioptric systems
    • G02B17/0804Catadioptric systems using two curved mirrors
    • G02B17/0808Catadioptric systems using two curved mirrors on-axis systems with at least one of the mirrors having a central aperture
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00Systems with reflecting surfaces, with or without refracting elements
    • G02B17/08Catadioptric systems
    • G02B17/0852Catadioptric systems having a field corrector only

Definitions

  • the present invention relates generally to catadioptrics and the more specifically to a large catadioptric objective arrangement.
  • secondary spherical mirrors the primary being a mangin mirror; large corrector elements forward of the primary, the rear surface of one of the elements being coincident with the secondary mirror; and field corrector means near the focal plane of the system.
  • the forwardmost of the corrector elements is positive so that the primary need not be larger than such element.
  • All of the surfaces of the catadioptric can be spherical and a common glass can be employed throughout.
  • One objective lens system in accordance with the invention and illustrated herein for specific use with an image intensifier incorporating an S-20 extended red sensor whose sensitive spectral region extends from 0.04 to 0.9 microns resolves 1,130 lines/mm on axis, and 500 lines/mm at the edge of the field, with considerations of observation and transmission, yielding a T/number of L93.
  • the same objective system has been found to have a reasonable performance as far as 1.2 microns and, hence, anticipates the needs of future image intensifiers that are sensitive to spectral regions extending into the near IR.
  • FIG. 1 is a schematic diagram illustrating a preferred embodiment of the objective lens system of the present invention
  • FIG. 2 is a sectional view illustrating the housing and mountings for the objective lens system of FIG. 1;
  • FIGS. 3A-3D are performance charts for an objective lens system of the present invention.
  • a large aperture objective system in accordance with the present invention comprises a catadioptric arrangement that includes a primary mirror 10, a secondary mirror 12, a number of relatively large corrector elements 14 forward of the primary l0, and field corrector means 16 near the focal plane P of the system.
  • the corrector elements 14 comprise three large diameter lenses l8, l9 and 20 and the field corrector means 16 comprises a pair of smaller lenses 22 and 24.
  • the first or forwardmost corrector element 18 is a positive lens therebyinsuring that the primary 10 need not be any larger than lens 18.
  • the third or forwardleast of the correctors 20' is combined with the primary 10 to jointly therewith form a Mangin type mirror 26.
  • the system is compensated so that the rear surface of thesecond-or intermediate lens 19 of the corrector elements I4 is made coincident with the secondary mirror 12. All of the surfaces of the objective lens system are spherical, a common glass being employed throughout.
  • FIG. 2 illustrates the housing and support structure for the objective.
  • the two large corrector elements l8 and 19 are shown each supportedby and sealed into a main tubular support structure 32, the elements I8 and 19 being cushioned and centralized by potting compound around the circumference.
  • the field correctors 22 and 24 are sealed in a tubular cell 40 that can be axially adjusted to eliminate any residual spherical aberration.
  • position accuracy is basically built into the machining of the structural members by holding tolerances of 0.001 inches at most places, but it will be appreciated that enough versatility exists to use shimming if required.
  • the air space between the Mangin 26 and the secondary mirror 12 is held to within i 0.006 inches and a more relaxed i 0.024-inch air space tolerance between the first and second elements l8, l9. Decentration of any of the lenses does not burden the system performance, and can be easily held within 10.01 inches to the optical axis.
  • the performance specifications for the illustrated embodiment are in terms of square wave transfer function (MTF).
  • MTF square wave transfer function
  • the minimum permissible transfer function for our requirements is 66 percent at 40 lines/mm for the axial case, and 38 percent modulation at 40 lines/mm at 2 off-axis.
  • the computed and measured axial MTF of the objective is shown in FIG. 3.
  • the axial MTF theoretically is 87 percent at 40 lines/mm, and it is anticipated that it could degrade as much as l0 per- 7 Radius (mm.) Thickness (mm.) Clear Surface (calculated) (center) Aperture (mm.)
  • Airspace adjustable 1 2.0 millimeters APER. STOP SURF b. 2.0
  • a catadioptric objective comprising a primary and a secondary mirror, three refractive correctors of relatively large clear aperture forward of the primary mirror and field corrector means comprising a pair of refractive elements of relatively small clear aperture near the focal plane, said objective being characterized v by the following parameters:
  • surfaces a and b have reference respectively the forward and rear surfaces of the forwardmost of said correctors
  • surfaces 0 and d have reference respectively to the forward and rear surfaces of the intermediate of said correctors
  • surface c has reference to the forward surface of the forwardleast of said correctors
  • surface f has reference to the rear surface of the forwardleast corrector and to the surface of the primary mirror
  • surface g has reference to the surface of the secondary mirror
  • surfaces h, i, j, k and l have A reference respectively to the surfaces of said pair of refractive elements.

Abstract

An objective system of high relative aperture for low-lightlevel application comprises a catadioptric system, utilizing a single glass type and only spherical surfaces, and includes three large correctors in front of the primary, and a field corrector element located near the focal plane. One of the large corrector elements is combined with the primary to form a Mangin mirror, the secondary is made coincident with the rear surface of the intermediate corrector, and the forwardmost of the corrector elements is positive.

Description

United States Amon et al.
541 LARGE CATADIOPTRIC OBJECTIVE [75] Inventors: Max Amon, Farmingdale; Seymour Rosin, Massapequa, both of [73] Assignee: Kollsman Instrument Corporation,
Syosset, N.Y.
[22] Filed: April 12, 1971 [21] Appl.No.: 133,223
[52] US. Cl. ..350/201 [51] Int. Cl. ..G02b 17/08 [58] Field of Search ..350/20l, 199
[56] References Cited I Q UNITED STATES PATENTS 2,520,635 8/1950 Grey ..350/20l 3,547,525 l2/l970 Rayces et al ..350/20l X 4 1 Jan. 16,1973
Primary Examiner-David Schonberg Assistant Examiner--Paul A. Sacher Attorney-E. Manning Giles, J. Patrick Cagney, Michael A. Kondzella and Richard A. Zachar [57] ABSTRACT An objective system of high relative aperture for low-' 1 Claim, 6 Drawing Figures PATENTEDJAN 16 I975 SHEET 1 OF 2 FIG.|
FIG.2
INVENTORS MAX AMO/V ssmoun ROS/N BY- d 3 4 2 AT'TORNEY LARGE CATADIOPTRIC OBJECTIVE BACKGROUND OF THE INVENTION The present invention relates generally to catadioptrics and the more specifically to a large catadioptric objective arrangement.
SUMMARY OF THE INVENTION secondary spherical mirrors, the primary being a mangin mirror; large corrector elements forward of the primary, the rear surface of one of the elements being coincident with the secondary mirror; and field corrector means near the focal plane of the system.
The forwardmost of the corrector elements is positive so that the primary need not be larger than such element. All of the surfaces of the catadioptric can be spherical and a common glass can be employed throughout.
One objective lens system, in accordance with the invention and illustrated herein for specific use with an image intensifier incorporating an S-20 extended red sensor whose sensitive spectral region extends from 0.04 to 0.9 microns resolves 1,130 lines/mm on axis, and 500 lines/mm at the edge of the field, with considerations of observation and transmission, yielding a T/number of L93. The same objective system has been found to have a reasonable performance as far as 1.2 microns and, hence, anticipates the needs of future image intensifiers that are sensitive to spectral regions extending into the near IR.
Other features and advantages of the invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which show structure embodying preferred features of the present invention and the principles thereof, and what is now considered to be the best mode in which to apply these principles.
BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings forming a part of the specification, and in which like numerals are employed to designate like parts throughout the same:
FIG. 1 is a schematic diagram illustrating a preferred embodiment of the objective lens system of the present invention;
FIG. 2 is a sectional view illustrating the housing and mountings for the objective lens system of FIG. 1;
FIGS. 3A-3D are performance charts for an objective lens system of the present invention.
DETAILED DESCRIPTION With reference now to the drawings and, specifically to FIG. 1, a large aperture objective system in accordance with the present invention comprises a catadioptric arrangement that includes a primary mirror 10, a secondary mirror 12, a number of relatively large corrector elements 14 forward of the primary l0, and field corrector means 16 near the focal plane P of the system.
In the illustrated embodiment, the corrector elements 14 comprise three large diameter lenses l8, l9 and 20 and the field corrector means 16 comprises a pair of smaller lenses 22 and 24. The first or forwardmost corrector element 18 is a positive lens therebyinsuring that the primary 10 need not be any larger than lens 18. The third or forwardleast of the correctors 20' is combined with the primary 10 to jointly therewith form a Mangin type mirror 26. In the preferred form the system is compensated so that the rear surface of thesecond-or intermediate lens 19 of the corrector elements I4 is made coincident with the secondary mirror 12. All of the surfaces of the objective lens system are spherical, a common glass being employed throughout. In the preferred form illustrated herein, F11 glass, developed by Schott, is employed because of its high index (1.620 at= 0.5876'microns), its efficiency with a single magnesium flouride anti-reflection coating (yielding 6 percent gain in transmission for the 10' airglass surfaces over the more common 1.5 index glasses), as well as because of its unusual properties of high rigidity and light weight.
FIG. 2 illustrates the housing and support structure for the objective. In FIG. 2 the two large corrector elements l8 and 19 are shown each supportedby and sealed into a main tubular support structure 32, the elements I8 and 19 being cushioned and centralized by potting compound around the circumference.
The field correctors 22 and 24 are sealed in a tubular cell 40 that can be axially adjusted to eliminate any residual spherical aberration.
In the illustrated embodiment position accuracy is basically built into the machining of the structural members by holding tolerances of 0.001 inches at most places, but it will be appreciated that enough versatility exists to use shimming if required. The air space between the Mangin 26 and the secondary mirror 12 is held to within i 0.006 inches and a more relaxed i 0.024-inch air space tolerance between the first and second elements l8, l9. Decentration of any of the lenses does not burden the system performance, and can be easily held within 10.01 inches to the optical axis.
The performance specifications for the illustrated embodiment are in terms of square wave transfer function (MTF). The minimum permissible transfer function for our requirements is 66 percent at 40 lines/mm for the axial case, and 38 percent modulation at 40 lines/mm at 2 off-axis. The computed and measured axial MTF of the objective is shown in FIG. 3. The axial MTF theoretically is 87 percent at 40 lines/mm, and it is anticipated that it could degrade as much as l0 per- 7 Radius (mm.) Thickness (mm.) Clear Surface (calculated) (center) Aperture (mm.)
a 969.92 15.0 (Glass) 232.0 6 116.70 (Air) 231.4 3 l 80.7 10.0 (Glass) 214.3 d 4778.6 133.13 (Air) 213.6 2 432.79 20.0 (Glass) 197.0 f v 631.40 20.0 (RefL) 199.2 g 432.79 133.13 (Air) h 4778.6 138.88 (Refl.) 110.4 1' 326.71 8.0 (Class) 64.2 j 492.95 7.47 (Air) 62.2 k 116.64 10.0 (Glass) 58.4 I 483.91 27.727 (Air) 55.4
Airspace adjustable 1 2.0 millimeters APER. STOP SURF b. 2.0
ENT. PUPIL DIA. 232.0 mm.
ENT.PUP1L LOC =9.315 mm.
EXT. PUPIL LOC 255.02 mm.
OVERALL LENGTH 332.78
EFL 345.8 mm.
BFL 26.727 mm.
f/No. 1.49 T.No. 2.0 SEMI FIELD ANGLE 3.2 SPEC. RANGE 0.4 to 0.9
While preferred embodiment is designed for S-20 extended red sensor whose sensitive spectral region extends from 0.4 to 0.9 microns, further analysis has shown that the system performance remains reasonable as far as 1.2 microns. This objective system of the present invention, therefore, anticipates the needs of future image intensifiers that are sensitive to spectral regions extending into the near IR.
While preferred constructional features of the invention are embodied in the structure illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit and scope of the appended claims.
What is claimed is:
l. A catadioptric objective comprising a primary and a secondary mirror, three refractive correctors of relatively large clear aperture forward of the primary mirror and field corrector means comprising a pair of refractive elements of relatively small clear aperture near the focal plane, said objective being characterized v by the following parameters:
Radius (mm.) Thickness (mm.) Clear Surface (calculated) (center) Aperture (mm).
a 969.92 15.0 (Glass) 232.0 b 116.70 (Air) 231.4 c 3 1 80.7 10.0 (Glass) 214.3 d 4778.6 133.13 (Air) 213.6 e 432.79 20.0 (Glass) 197.0 f 432.79 20.0 (RefL) 199 2 g 432.79 l33.13 (Air) h 4778.6 138.88 (RefL) 110.4 1' 326.71 8.0 (Glass) 64.2 j 492.95 7.47 (Air) 62.2 k 116.64 10.0 (Glass) 58.4 1 483.91 27.727 (Air). 55.4
* Airspace adjustable 2.0 millimeters wherein surfaces a and b have reference respectively the forward and rear surfaces of the forwardmost of said correctors, surfaces 0 and d have reference respectively to the forward and rear surfaces of the intermediate of said correctors, surface c has reference to the forward surface of the forwardleast of said correctors, surface f has reference to the rear surface of the forwardleast corrector and to the surface of the primary mirror, surface g has reference to the surface of the secondary mirror, and surfaces h, i, j, k and l have A reference respectively to the surfaces of said pair of refractive elements.

Claims (1)

1. A catadioptric objective comprising a primary and a secondary mirror, three refractive correctors of relatively large clear aperture forward of the primary mirror and field corrector means comprising a pair of refractive elements of relatively small clear aperture near the focal plane, said objective being characterized by the following parameters: Radius (mm.)Thickness (mm.)ClearSurface(calculated)(center)Aperture (mm). a969.9215.0(Glass) 232.0b-116.70(Air) 231.4c-3180.710.0(Glass) 214.3d-4778.6133.13(Air) 213.6e- 432.7920.0(Glass) 197.0f432.79- 20.0(Refl.) 199.2g-432.79-133.13(Air) h4778.6138.88*(Refl.) 110.4i326.718.0(Glass) 64.2j492.957.47(Air) 62.2k116.6410.0(Glass) 58.4l483.9127.727(Air) 55.4* Airspace adjustable + OR - 2.0 millimeters wherein surfaces a and b have reference respectively the forward and rear surfaces of the forwardmost of said correctors, surfaces c and d have reference respectively to the forward and rear surfaces of the intermediate of said correctors, surface e has reference to the forward surface of the forwardleast of said correctors, surface f has reference to the rear surFace of the forwardleast corrector and to the surface of the primary mirror, surface g has reference to the surface of the secondary mirror, and surfaces h, i, j, k and l have reference respectively to the surfaces of said pair of refractive elements.
US00133223A 1971-04-12 1971-04-12 Large catadioptric objective Expired - Lifetime US3711184A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US13322371A 1971-04-12 1971-04-12

Publications (1)

Publication Number Publication Date
US3711184A true US3711184A (en) 1973-01-16

Family

ID=22457556

Family Applications (1)

Application Number Title Priority Date Filing Date
US00133223A Expired - Lifetime US3711184A (en) 1971-04-12 1971-04-12 Large catadioptric objective

Country Status (1)

Country Link
US (1) US3711184A (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0046443A1 (en) * 1980-08-16 1982-02-24 Ludvik Dr. Canzek Wide aperture catadioptric objective
US4411499A (en) * 1980-11-07 1983-10-25 Honeywell Inc. Compact optical system
US4456343A (en) * 1980-10-17 1984-06-26 Ludvik Canzek High speed catadioptric objective lens system
US5471346A (en) * 1992-03-13 1995-11-28 Lockheed Missiles & Space Co., Inc. Casegrain telescope with spherical mirror surfaces
EP0770224A1 (en) * 1994-06-07 1997-05-02 Industrial Research Limited High speed optical system
US5631778A (en) * 1995-04-05 1997-05-20 National Research Council Of Canda Panoramic fish-eye imaging system
US20050179994A1 (en) * 2004-02-18 2005-08-18 Webb James E. Catadioptric imaging system for high numerical aperture imaging with deep ultraviolet light
US20140300959A1 (en) * 2013-04-05 2014-10-09 University Of Florida Research Foundation, Incorporated Telescope and telescope array for use in spacecraft
US10133043B1 (en) * 2016-09-05 2018-11-20 Telelens LLC. Compact telephoto lens camera suitable for use in smart phones and similar devices, and methods of using same
RU220310U1 (en) * 2023-06-06 2023-09-06 Акционерное общество "ЛОМО" MIRROR LENS

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2520635A (en) * 1949-03-10 1950-08-29 Polaroid Corp Optical system
US3547525A (en) * 1967-08-31 1970-12-15 Perkin Elmer Corp Catadioptric system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2520635A (en) * 1949-03-10 1950-08-29 Polaroid Corp Optical system
US3547525A (en) * 1967-08-31 1970-12-15 Perkin Elmer Corp Catadioptric system

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0046443A1 (en) * 1980-08-16 1982-02-24 Ludvik Dr. Canzek Wide aperture catadioptric objective
US4398809A (en) * 1980-08-16 1983-08-16 Ludvik Canzek High speed catadioptric system
US4456343A (en) * 1980-10-17 1984-06-26 Ludvik Canzek High speed catadioptric objective lens system
US4411499A (en) * 1980-11-07 1983-10-25 Honeywell Inc. Compact optical system
US5471346A (en) * 1992-03-13 1995-11-28 Lockheed Missiles & Space Co., Inc. Casegrain telescope with spherical mirror surfaces
EP0770224A1 (en) * 1994-06-07 1997-05-02 Industrial Research Limited High speed optical system
EP0770224A4 (en) * 1994-06-07 1998-11-25 Ind Res Ltd High speed optical system
US5631778A (en) * 1995-04-05 1997-05-20 National Research Council Of Canda Panoramic fish-eye imaging system
US20050179994A1 (en) * 2004-02-18 2005-08-18 Webb James E. Catadioptric imaging system for high numerical aperture imaging with deep ultraviolet light
WO2005081030A1 (en) * 2004-02-18 2005-09-01 Corning Incorporated Catadioptric imaging system for high numerical aperture imaging with deep ultraviolet light
US7564633B2 (en) 2004-02-18 2009-07-21 Corning Incorporated Catadioptric imaging system for high numerical aperture imaging with deep ultraviolet light
US20140300959A1 (en) * 2013-04-05 2014-10-09 University Of Florida Research Foundation, Incorporated Telescope and telescope array for use in spacecraft
JP2017513074A (en) * 2013-04-05 2017-05-25 ユニバーシティ オブ フロリダ リサーチ ファウンデーション,インコーポレイティド Telescopes and telescope arrays used in spacecraft
US9846299B2 (en) * 2013-04-05 2017-12-19 University Of Florida Research Foundation, Incorporated Telescope and telescope array for use in spacecraft
US10416423B2 (en) 2013-04-05 2019-09-17 University Of Florida Research Foundation, Incorporated Telescope and telescope array for use in spacecraft
US10133043B1 (en) * 2016-09-05 2018-11-20 Telelens LLC. Compact telephoto lens camera suitable for use in smart phones and similar devices, and methods of using same
RU220310U1 (en) * 2023-06-06 2023-09-06 Акционерное общество "ЛОМО" MIRROR LENS

Similar Documents

Publication Publication Date Title
US3244073A (en) Centered optical mirror system having finite conjegates
GB677982A (en) Improvements in or relating to telescopes
US4061420A (en) Catadioptric lens system
GB1119910A (en) Improvements relating to device comprising electron-optical night telescopes
CN105759410A (en) Refraction and reflection type large aperture and large field of view imaging system
US3752559A (en) Ritchey-chretien telescope
US2481639A (en) High-aperture copying lens system
US3711184A (en) Large catadioptric objective
WO2002093230A1 (en) High etendue optical imaging system
US3460886A (en) Telescopic system utilizing three axially aligned substantially hyperbolic mirrors
CN112147759B (en) Optical lens and electronic device
US2492461A (en) Corrected schmidt type optical system
CN111830672A (en) Optical lens and imaging apparatus
US3547525A (en) Catadioptric system
JPH09101456A (en) Objective lens system
US2817270A (en) Telescope objective systems
US4392710A (en) Optical apparatus
WO2001077734A1 (en) Compact imaging system including an aspheric quaternary element
US2608129A (en) Two-mirror telescope focusing system
US3180217A (en) Cassegrainian type telescope optical system utilizing a coma correcting meniscus
CN114236798A (en) Catadioptric afocal optical system
US2571657A (en) Catadioptric lens system
US3016798A (en) Compact achromatic telescope lens
US2968220A (en) Cassegrain mirror lens objective
CN110501800B (en) Optical lens