JPS6410206A - Lens system with long back focus - Google Patents

Lens system with long back focus

Info

Publication number
JPS6410206A
JPS6410206A JP62166215A JP16621587A JPS6410206A JP S6410206 A JPS6410206 A JP S6410206A JP 62166215 A JP62166215 A JP 62166215A JP 16621587 A JP16621587 A JP 16621587A JP S6410206 A JPS6410206 A JP S6410206A
Authority
JP
Japan
Prior art keywords
lens
lens system
long
focus
constitution
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.)
Pending
Application number
JP62166215A
Other languages
Japanese (ja)
Inventor
Akinaga Horiuchi
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 JP62166215A priority Critical patent/JPS6410206A/en
Publication of JPS6410206A publication Critical patent/JPS6410206A/en
Pending legal-status Critical Current

Links

Landscapes

  • Lenses (AREA)

Abstract

PURPOSE:To obtain a long-back-focus lens system of simple constitution which enables a color separation prism and various filters to be arranged behind a lens system, and has a back focus nearly as long as the focal length and high optical performance over the entire picture plane by composing the lens system of six lenses in specific shapes. CONSTITUTION:This lens system has a 1st meniscus lens which has its convex surface on an object side and negative refracting power, a 2nd biconvex lens which has larger curvature on the object side than on the image side, a 3rd biconcave lens, a 4th biconvex lens, a 5th lens with negative refracting power, and a 6th biconvex lens in order from the object side. Consequently, the long- back-focus lens system of simple lens constitution is obtained which consists of the six lens elements, has an about 40 deg. effective field angle, an about 2.8 F number, and its back focus nearly equal to the focal length, and allows the color separation prism, various filters, etc., to be arranged behind the lens system.
JP62166215A 1987-07-02 1987-07-02 Lens system with long back focus Pending JPS6410206A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62166215A JPS6410206A (en) 1987-07-02 1987-07-02 Lens system with long back focus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62166215A JPS6410206A (en) 1987-07-02 1987-07-02 Lens system with long back focus

Publications (1)

Publication Number Publication Date
JPS6410206A true JPS6410206A (en) 1989-01-13

Family

ID=15827240

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62166215A Pending JPS6410206A (en) 1987-07-02 1987-07-02 Lens system with long back focus

Country Status (1)

Country Link
JP (1) JPS6410206A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04174808A (en) * 1990-11-08 1992-06-23 Canon Inc retro focus lens
JPH04174807A (en) * 1990-11-08 1992-06-23 Canon Inc Retro-focus type lens

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04174808A (en) * 1990-11-08 1992-06-23 Canon Inc retro focus lens
JPH04174807A (en) * 1990-11-08 1992-06-23 Canon Inc Retro-focus type lens

Similar Documents

Publication Publication Date Title
JPS6457222A (en) Zoom lens for compact camera
JPS54157620A (en) Photographic telephoto lens
JPS54119233A (en) Finder optical system
JPS5659217A (en) Lens for compact camera of short overall length using aspherical face
JPS57190917A (en) Superwide-angle zoom lens
JPS5767908A (en) Wide-angle zoom lens
JPS5643618A (en) Attachment lens
JPS55147607A (en) Retrofocus type wide angle photographic lens
JPS57161822A (en) Large aperture ratio lens
JPS57171309A (en) Lens for compact camera having short total length
JPS54158225A (en) Photographic lens having long back focus and large aperture ratio
JPS6429812A (en) Refraction type optical system for video projector
JPS64512A (en) Albada system zoom finder
JPS5517132A (en) High contrast objective lens used in finite distance
JPS5659216A (en) Standard lens with wide angle of view
JPS6410206A (en) Lens system with long back focus
JPS557712A (en) Compact standard zoom lens
JPS5643619A (en) Wide angle zoom lens
JPS57163212A (en) Retrofocus wide-angle lens consisting of 5-sheets structure
JPS55111915A (en) Zoom lens
JPS5722215A (en) Photographic lens
JPS5443725A (en) Standard photographic lens
JPS565518A (en) Optical correction type variable focal length lens system
JPS5694318A (en) Lens system provided with rear converter lens
JPS6474519A (en) Zoom lens