SU1236412A1 - Photographic lens - Google Patents

Abstract

This invention relates to an optical instrument, in particular to long-focus photographic lenses for SLR cameras with a frame size of 24 x 36 mm. The aim of the invention is to improve the image quality: in a wide range of shooting distances and reduce the size of the device. The lens consists of four components, the first of which is made in the form of a single positive meniscus (m) 1. The second component is glued together from positive M 2 and, negative one M 3, Aperture aperture 5 is placed before the third component - 4 - The twisted component is a two-convex lens 6. Conditions are given from which the radii of the surfaces of the third component and the distance are selected by the second, third, and fourth components. Objective has a relative aperture. 1: 2.8, focal length 100 mm, optical block size 0 x L 36 x 53 mm. silt co (L co w

Description

The invention relates to optical instrument making, namely, to long focus photographic objects for SLR cameras with a frame size of 24 x 36 mm.

The purpose of the invention is to improve the quality of the image in a wide range of shooting distances and reduce the size.

The optical image of the photographic lens is shown in the drawing.

The proposed lens consists of four components formed by five lenses. The first component is a single positive meniscus 1. The second component is a positive doublet, glued from a positive 2 and a negative 3 meniscus. The third component is the negative meniscus 4. All menisci are turned with a concavity towards the image, in front of the negative meniscus there is an aperture aperture 5. The fourth component is made in the form of a two-convex lens 6,

The proposed lens is characterized by a relative aperture of 1: 2.8, a focal length for a frame of 24 mm is corrected for – 546.07 µm, achromatized for –– 435.83 µm and; 656.3 microns. When shooting objects that are distant for a long distance, the image quality is determined by the spherical aberration of & 0.015 mm, with a maximum size of 7; the handle for the points of the field in 10 mm is not more than 0.03 mm and for points of the field L | 20 mm no more than 0.05 mm

In the case of S7zeme objects that are 1.2 m apart, the spherical aberration does not increase, but Max H, Dumb 3086/48

Compiled by V. Arkhipov Tehred M. Morgental

Cor Pod

Circulation 501 VNIIPI State Committee on the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab. D. 4/5

Production and printing company, Uzhgorod, st. Project, 4

the maximum size of the circle of scattering points of the field and -10 mm does not rjpe- go up 0.06 mm and for the points of the field 20 NfM not more than 0.08 mm.

In the lens, the length from the first surface to the film plane is 96.3 mm, the dimensions of the optical unit are 0 X L 36x53 mm, the mass of optical parts is 67 g.

“The formula of the invention

A photographic lens containing four components, the first, the second and the third of which are respectively a positive single, put a fir-tree glued from positive and negative menisci, and a negative single meniscus facing a concavity to the image, the fourth is a positive lens, and an aperture diaphragm , about 10 a (and with the fact that, with a trick of improving the quality of the image in a wide range of shooting distances and reduction {abaritov), the fourth part is made in the form of a two-convex lens, aperture diagonal the fragment is installed between the second and third components, the radii r and r of the surfaces of the third component are chosen by jibi from the condition

G5

 15,

R

and the distances d, between the second and the third and d mulsda, the third and fourth components are selected # 1 from the condition

, 0.1 f dj d 0.16 f

I

where f is the focal length of the lens.

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Claims (2)

Claim A photographic lens containing four components, the first, 15th, second and third of which are positively single, positive, glued together from positive and negative menisci, and negative single menisci, 2Q facing with concavity to the image, the fourth is a positive lens, and an aperture diaphragm different the fact that, in order to improve image quality in 25 wide range of shooting distances and reduce dimensions, the fourth component is made in the form of a biconvex lens, aperture aperture mounted between the second and third components 30, radii and ₇ g of surfaces of a third component selected from the condition 2 15, ^G G and the distance d _? between the second and third and d ₆ between the third and fourth components are selected from the condition 0.1 fJd. id _fi <0.16 40. ^{5 6} 'ι where f is the focal length of the lens.