RU2079154C1 - Objective lens with discrete change of focal distance for nearest ir region of spectrum - Google Patents

Abstract

FIELD: optics. SUBSTANCE: proposed objective lens is related to special ones and is used to observe objects within spectrum region 0.6-1.0 μm. Objective lens includes four components. First and second components ensure maximum focal distance. In addition to first two components third and fourth components are brought in to ensure minimum focal distance. Aiming for distance is performed for both focal distances by movement of first component toward objective. EFFECT: improved functional stability and precision. 7 dwg

Description

 The invention relates to special lenses and can be used to observe the terrain in the near infrared region of the spectrum.

Known for the design of lenses with a discrete change in focal length [1] [2]
The closest in technical essence is the lens [3] with a discrete change in focal length.

 The prototype lens is made of the following sequentially arranged components and lenses in them, namely, the first component of a biconvex lens, a negative meniscus facing concavity to the object, and a biconvex lens; the second component is a glued lens, consisting of a positive meniscus convex to the object, and a negative meniscus facing the concavity of the image; the third component of the negative meniscus, facing concavity to the image, biconvex lens and biconcave lens; the fourth component consists of biconvex and biconcave lenses.

 Moreover, the third and fourth components are installed with the ability to input and output them from the optical circuit.

The specified lens is designed for the visible region of the spectrum of 0.434 0.656 μm, has a small magnification factor of m 2 ^x .

(-0,2), (-0,2), для

(-0,8), (-0,42), сагиттальную и меридиональную кривизну в пределах 0,2 мм.The lens has a relative aperture of 1 4.5 1 10.4, position chromatism and a secondary spectrum for

(-0.2), (-0.2), for

(-0.8), (-0.42), sagittal and meridional curvature within 0.2 mm.

 The objective of the invention is to provide a lens with a discrete change in focal length, having a large magnification, a higher relative aperture, higher image quality in the field.

1 1,5 1 4, меридиональная и сагиттальная кривизна в пределах 0,075 мм, хроматизма положения и вторичный спектр в пределах 0,085 мм для

и 0,041 мм для

Сущность изобретения заключается в том, что объектив с дискретным изменением фокусного расстояния для ближней ИК-области спектра, содержащий четыре компонента, причем третий и четвертый компоненты установлены с возможностью ввода и вывода их из оптической схемы, при этом первый компонент состоит из двояковыпуклой линзы, отрицательной линзы и двояковыпуклой линзы, второй компонент состоит из отрицательного мениска, обращенного вогнутостью к изображению, третий компонент состоит из отрицательной линзы, двояковогнутой линзы, двояковыпуклой линзы, четвертый компонент состоит из двояковыпуклой и двояковогнутой линз, в отличие от известного в первом компоненте отрицательная линза выполнена в виде двояковогнутой, первый компонент дополнен двояковогнутой линзой, склеенной с двояковыпуклой, и склеенной линзой, состоящей из выпуклоплоской и плосковогнутой линз; второй компонент дополнен отрицательным мениском, обращенным вогнутостью к предмету, третий компонент дополнен положительным мениском, обращенным выпуклостью к изображению и расположенным первым в компоненте и склеенным с отрицательной линзой, которая имеет форму двояковогнутой, двояковогнутая и двояковыпуклая линзы склеены, в четвертом компоненте двояковыпуклая и двояковогнутая линзы склеены, четвертый компонент дополнен склеенной линзой, состоящей из двояковыпуклой и двояковогнутой линз, и склеенной линзой, состоящей из двояковыпуклой и двояковогнутой линз.The technical result of the magnification is 4.2 ^x , the relative aperture for

1 1.5 1 4, meridional and sagittal curvature within 0.075 mm, position chromatism and secondary spectrum within 0.085 mm for

and 0.041 mm for

The essence of the invention lies in the fact that the lens with a discrete change in focal length for the near infrared region of the spectrum containing four components, the third and fourth components are installed with the possibility of input and output from the optical circuit, while the first component consists of a biconvex lens, negative lens and biconvex lens, the second component consists of a negative meniscus facing concavity to the image, the third component consists of a negative lens, biconcave lens, biconvex a cohesive lens, the fourth component consists of a biconvex and biconcave lenses, in contrast to the known in the first component, the negative lens is made in the form of a biconcave, the first component is supplemented by a biconcave lens glued with a biconvex, and a glued lens, consisting of a convex and plano-concave lenses; the second component is complemented by a negative meniscus facing concavity to the object, the third component is complemented by a positive meniscus convex to the image and located first in the component and glued to a negative lens, which has the shape of a biconcave, biconcave and biconvex lenses glued together, in the fourth component a biconvex and biconvex and biconvex lens glued, the fourth component is supplemented by a glued lens, consisting of a biconvex and biconcave lens, and a glued lens, consisting of two convex and biconcave lenses.

 This embodiment allows you to get a lens with the characteristics presented in the table.

In FIG. 1 is an optical diagram of a lens; in FIG. 2 - lens construction elements cf ′ = 107.87 mm, 1: 1.5, 2σ = 6 ^° 1′49 ″ in FIG. 3 lens structural components cf ′ = 450.84 mm, 1: 4, 2σ = 1 ^q 23′53 ″ in FIG. 4 aberration plots for f ^' 107.87 mm; in FIG. 5 graphs of aberrations for f ^' 450.84 mm; in FIG. 6 graphs of the modulation transmission coefficient (KPM) for f ^' 107.87 mm; in FIG. 7 - KPM graphs for f ^' 450.84 mm.

The lens with a discrete focal length change for the near infrared region of the spectrum consists of four components, the third and fourth components are installed with the ability to input and output them from the optical circuit, the first component consists of a biconvex lens 1, a biconcave lens 2, a glued lens consisting of a biconvex lens 3 and a biconcave lens 4, a glued lens consisting of a convex flat lens 5 and a flat-concave lens 6. The second component consists of a negative meniscus 7, facing the concavity to the image, and negate solid meniscus 8, facing concavity to the subject; the third component consists of a glued lens, consisting of a positive meniscus 9, convex to the image, and a biconcave lens 10, a glued lens, consisting of a biconcave lens 11 and a biconvex lens 12; a fourth component consists of a glued lens consisting of a biconvex lens 13 and biconcave lens 14 glued lens consisting of a biconvex lens 15, a biconcave lens 16 glued lens consisting of a biconvex lens 17 and biconcave lens 18. For f ¹ 450.84 mm aperture the diaphragm is located on the first surface of the lens pos. 1 For f ¹ 107.87 mm, the aperture diaphragm is located on the first surface of the lens pos. 9.

 The lens works as follows.

 The first component (lenses pos. 1, 2, 3, 4, 5, 6) and the second component (lenses pos. 7, 8) provide a focal length of 450.84 mm. The first component (lenses pos. 1, 2, 3, 4, 5, 6), the second component (lenses pos. 7, 8), the third component (lenses pos. 9, 10, 11, 12), the fourth component (lenses pos. . 13, 14, 15, 16, 17, 18) provide a focal length of 107.8 mm. Aiming at a distance of D 50 m is carried out by moving the first component to the subject at a distance of 2.65 mm. The illumination at the receiver is adjusted by variable-density filters applied to two plane-parallel plates that are in front of the receiver.

Claims (1)

 A lens with a discrete focal length change for the near infrared region of the spectrum containing four components, the third and fourth components being mounted for input and output from the optical circuit, the first component comprising a biconvex and negative lens, the second component made of a negative meniscus, facing concavity to the image, the third component contains a biconcave lens, characterized in that in the first component the negative lens is biconcave and it is complemented by two menisci, the first of which is glued from a biconvex and biconcave lenses, and the second from a convex-plane and flat-concave lenses, the second negative meniscus is introduced into the second component, facing concavity to the object, in the third component the biconcave lens is glued from the positive meniscus, turned concave to the object, and a biconcave lens and is located first, behind which a double-glued meniscus is introduced, consisting of a biconcave and biconvex lens, and the fourth component is made in the form of three menisci, each of which glued from biconvex and biconcave lenses.

Images