SU1339476A1 - Zoom lens - Google Patents

Abstract

The invention can be used in tele-equipment and allows for an increase in the back focal length. relative aperture of the lens and improve color reproduction. The lens consists of an apokalevnoy system 1 with variable magnification and a power unit 2. In block 2 between the two-convex lens 21 and the negative 23 and positive 24 meniscus interconnected by meniscus there is a two-curved lens 22, the positive 25 and the negative 26 menisci are glued into a positive component, which has a dual bucket lens 27. In. System 1 components 4 and 6 are installed with the possibility of simultaneous movement of the optical axis of the lens relative to stationary components 3.5 and 7. When the lens is installed in a color television camera, behind unit 2, a prism unit is installed to separate the luminous flux. 1 il. SL Prizmenny OO oo s 4; :: O5

Description

The invention relates to optical instrumentation, namely, lenses with variable focal length, and can be used in professional and amateur television equipment, in particular, for color television cameras using mm transmission tubes and video and television equipment,

The purpose of the invention is to increase the rear focal segment of the relative aperture and improve color reproduction.

The drawing shows the principal optical layout of a lens with a variable focal length.

The lens consists of an afocal system with a variable value of 1 and a power unit 2. The afocal system 1 is formed by five components 3-7, of which components 4 and 6 are installed with the possibility of simultaneous movement along the optical axis of the lens relative to fixed components 3.5 and 7, The components of the system 1 are made: 3 - made of glued two-convex lenses 8 and a negative meniscus 9 and a single two-convex lenses 10; 4 - from a single negative meniscus 1T, convex to the object, and a concave-flat lens 12; 5 - from a flat-convex lens 13 and a positive meniscus 14, convex to the object; 6 - of two identical, separated by an air gap, glued pairs of lenses, of which the first consists of flat-convex 15 and two-concave 16 lenses, the second - from double-concave 17 and flat-convex lenses 18; 7 - from a glued pair of LENSES, the first of which is flat-folded 19, and the second - a two-doll 20.

Power unit 2 contains five components; 21 - single lump lens; 22 - single d; in the case of a lens; negative 23 and positive 24 menisci are glued to the negative component, and positive 25 and negative 26 menisci are glued to the positive component; 27 - two co-convex lens.

Between the afocal system 1 and the power unit 2 there is an aperture-diaphragm with a diameter of 12.1 mm, located at a distance of 1.5 mm

from component 7. A prism unit is installed in the color television camera behind the power unit 2 to install the variable focal length lens into the color television camera to separate the light flux.

The range of change of the focal lengths of the proposed lens

10.58 - 43.02 mm, relative aperture 1: 1.7, linear image size 2–8 mm, rear focal length 5p 24.38 mm. The lens is corrected for wavelength 1, achromatized in the wavelength range c-g. Distance focusing is performed by moving component 3. The minimum shooting distance is 1.5 m.

The lens has a telecentric

the course of the main rays in the space of images, which improves color reproduction.

Image quality: at a focal length of 10.58 mm transverse

spherical aberration no more than 0.008 mm, position chromatism no more than 0.096 mm, for angles of inclination up to .21 ° 25, the sagittal curvature is 0.121 mm, meridional 0.057 mm, astigmatism no more than 0.072 mm, distortion is no more than 9.3%, chromatism of an increase of 0.004 mm, aberration of wide oblique beams no more than 0,018 mm.

With a focal length of 43.066 mm

transverse spherical aberration on the edge of the pupil of no more than 0.019 mm, position chromatism of no more than 0.102 mm, for angles of inclination to a sagittal curvature of 0.073 mm, meridional 0.105 mm, astigmatism of no more than 0.176 mm, distortion of no more than 0.88%, increase chromatism of no more than 0.01 mm, aberration of wide oblique beams, not more than 0.016 mm.

Claims (1)

Invention Formula A variable focal length lens containing an afocal system of variable magnification of five components, the first, third and five of which are fixed, and the second and fourth are made with the possibility of simultaneous movement along the optical axis, and the power unit, of four components, and afocal system ac 31 neither the first positive component contains a positive lens glued together from a two-convex lens and a negative meniscus, and a two-convex lens, the second negative component is a negative meniscus convex to the object, and a cello-flat lens, the third positive component - a flat-convex lens and a field of a thermal meniscus convex to the object; the fourth negative component is two negative lenses, each of which is glued together from a convex and double-concave lenses, mutually facing concave Tube to each other, the fifth component is a positive lens, glued from flat-concave and two 39476- convex lenses, in the power block the first component is a positive lens, the second and third} are menisci, the fourth is a duplex lens, characterized in that in order to increase the back focal length of the relative aperture and improve color reproduction, in the power block between the first and second the components are fitted with a double-concave lens, the first component is made in the form of a double convex lens, the third one is made up of negative glued and has a flat meniscus facing t with a concavity to the object, and the third component is made of Leen positive and negative meniscus facing the concavity of the subject. ten