JPS56111825A - Lens system with function of varying focal length easily - Google Patents

Lens system with function of varying focal length easily

Info

Publication number
JPS56111825A
JPS56111825A JP1508180A JP1508180A JPS56111825A JP S56111825 A JPS56111825 A JP S56111825A JP 1508180 A JP1508180 A JP 1508180A JP 1508180 A JP1508180 A JP 1508180A JP S56111825 A JPS56111825 A JP S56111825A
Authority
JP
Japan
Prior art keywords
lens
focal length
power
function
positive
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.)
Granted
Application number
JP1508180A
Other languages
Japanese (ja)
Other versions
JPS6146808B2 (en
Inventor
Kazuo Tanaka
Keiji Ikemori
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Priority to JP1508180A priority Critical patent/JPS56111825A/en
Publication of JPS56111825A publication Critical patent/JPS56111825A/en
Publication of JPS6146808B2 publication Critical patent/JPS6146808B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B15/00—Optical objectives with means for varying the magnification
    • G02B15/02—Optical objectives with means for varying the magnification by changing, adding, or subtracting a part of the objective, e.g. convertible objective
    • G02B15/10—Optical objectives with means for varying the magnification by changing, adding, or subtracting a part of the objective, e.g. convertible objective by adding a part, e.g. close-up attachment

Abstract

PURPOSE:To enable to vary focal length with compact constitution, by bearing prescribed relation between a master lens and auxiliary lens. CONSTITUTION:Auxiliary lens 12 provided, being insertable and extractable, on the optical path between master lens 11 and an image surface, varies the focal length of the whole lens system. With lens 12 insertd extracted, the distance between lens 11 and the image surface is unchanged and the conditions of formulas I are satisfied. In the formulas, phi1 is the power of lens 11, e1' the distance from the image-field-side principal point of lens 11 to the object-field-side principal point of lens 12, phi2 the power of lens 12, (DELTA) the principal-point interval of lens 12, and (m) the ratio between the power of only lens 11 and that of the whole system when lens 12 is equipped. Further, lens 12 has positive power and consists of positive, negative and positive lenses.
JP1508180A 1980-02-08 1980-02-08 Lens system with function of varying focal length easily Granted JPS56111825A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1508180A JPS56111825A (en) 1980-02-08 1980-02-08 Lens system with function of varying focal length easily

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1508180A JPS56111825A (en) 1980-02-08 1980-02-08 Lens system with function of varying focal length easily

Publications (2)

Publication Number Publication Date
JPS56111825A true JPS56111825A (en) 1981-09-03
JPS6146808B2 JPS6146808B2 (en) 1986-10-16

Family

ID=11878890

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1508180A Granted JPS56111825A (en) 1980-02-08 1980-02-08 Lens system with function of varying focal length easily

Country Status (1)

Country Link
JP (1) JPS56111825A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3329046A1 (en) * 1982-08-11 1984-02-16 Ricoh Co., Ltd., Tokyo LENS SYSTEM
WO2003077006A1 (en) * 2002-03-14 2003-09-18 Sony Corporation Imaging device and zoom lens
JP2015041003A (en) * 2013-08-22 2015-03-02 株式会社ニコン Rear wide-converter lens, image capturing device having rear wide-converter lens, and manufacturing method for rear wide-converter lens
WO2016035119A1 (en) * 2014-09-01 2016-03-10 株式会社ニコン Rear-type wide converter lens, image pickup device having rear-type wide converter lens, and method for manufacturing rear-type wide converter lens

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5413729A (en) * 1977-07-04 1979-02-01 Kokusai Electric Co Ltd Method of transmitting diversity
JPS5433027A (en) * 1977-08-19 1979-03-10 Nitto Optical Camera having focall distance changeeover lens
JPS54135546A (en) * 1978-04-13 1979-10-20 Canon Inc Lens system for mounting and dismounting auxiliary lens

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5413729A (en) * 1977-07-04 1979-02-01 Kokusai Electric Co Ltd Method of transmitting diversity
JPS5433027A (en) * 1977-08-19 1979-03-10 Nitto Optical Camera having focall distance changeeover lens
JPS54135546A (en) * 1978-04-13 1979-10-20 Canon Inc Lens system for mounting and dismounting auxiliary lens

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3329046A1 (en) * 1982-08-11 1984-02-16 Ricoh Co., Ltd., Tokyo LENS SYSTEM
WO2003077006A1 (en) * 2002-03-14 2003-09-18 Sony Corporation Imaging device and zoom lens
US7583300B2 (en) 2002-03-14 2009-09-01 Sony Corporation Imaging device and zoom lens
JP2015041003A (en) * 2013-08-22 2015-03-02 株式会社ニコン Rear wide-converter lens, image capturing device having rear wide-converter lens, and manufacturing method for rear wide-converter lens
WO2016035119A1 (en) * 2014-09-01 2016-03-10 株式会社ニコン Rear-type wide converter lens, image pickup device having rear-type wide converter lens, and method for manufacturing rear-type wide converter lens

Also Published As

Publication number Publication date
JPS6146808B2 (en) 1986-10-16

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