SU1422206A1 - Zoom eyepiece - Google Patents

Abstract

FIELD: optical instrumentation; used in visual optical instruments to obtain variable magnification. The purpose of the invention is to expand the range of focal distance. The positive component 1 is glued together from two convex lenses 3, 4 and a double-curved lens 5 placed between them and adapted to move along an axis. The fixed positive component 2 is glued together from the double-constricted lens 6 to the negative meniscus 7. In the first extreme position of the component I, the axial point of the object is aligned with the top of its last surface, and the first its surface is concentric to the axial point of the object, since the radii of the outer surfaces of the component are equal to its thickness. In this position, the increase in component 1 is l / n, where n is the refractive index of lens materials 3, 4, 5. In the second extreme component, the top of its first surface is aligned with the axial point of the object, and the last surface is concentric with the axial point of the object, so that in this position, the increase in component 1 is equal to p. The magnitude of the change in the focal length of the ocular p & equal to n i pc, keodl

Description

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The invention relates to an optical instrument, namely, a pancratical eyepiece, and can be used in visual optical devices for providing variable magnification.

The aim of the invention is to expand the range of focal length variation,

The drawing shows an optical scheme for the ocular,

The oculare consists of two components AND 2. The first component is made of glued together two identical positive two-convex lenses 3 and 4 and a negative two-concave lens 5 located between them, in which case all the lenses have the same indications of refraction. Component 1 has a positive optical power, the outer radii of component 1 are equal in magnitude to its thickness and opposite in sign. The second component is glued from a positive 6 and a negative 7 lenses, while the ratio of the outer radius of the first component to the focal distance of the second component is 0.82-0.67. The ocular plane is located in the front focal ixnoCKOcTH of the second component.

The change of the focal distance is accomplished by moving the first component. In the first extreme of its position (solid line), the first component surface is concentric with the axial point of the object, and the top of the last surface of the component is aligned with the axial point of the object. In this case, the own increase

1 of the first component is equal to where

n is the refractive index of the component lenses. In the second extreme position of the first component (dotted line), the top of the first surface of the component is aligned with the axial point of the object, and the last surface concentric to the axial point of the preset in this case, the first component is equal to n. Thus, the displacement of the first component ensures that the ocular focal length changes equal to n. Since 55 ak the subject is located in the feather, the focus of the second component, then with an increase of equal to n, it is necessary that

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the front focal segment of the second component was larger in magnitude of the last radius of the first component. In addition, the dioptricity change in the ocular is performed by moving the second component, therefore, the ratio of the external radius to the focal length of the second component is 0.82-0.67.

The proposed ocular has the following basic characteristics: focal length f 46.62-15.24 mm; change rate f -3.06; angular field of view 2 with ZO; relative hole 1:12.

With a maximum focal length in the reverse direction of the rays, the longitudinal spherical aberration is no more than 0.6 mm, the chromatism of the position is no more than 0.15 mm, the astigmatism is no more than 2 mm, the aberrations of the mipoKoro meridional beam are no more than 0.175 mm.

At the minimum focal length, the longitudinal spherical aberration is no more than 0.04 mm, the chromatism of the position is no more than 0.04 mm, the astigmatism is no more than 0.3 mm, the aberrations of the wide meridional beam are no more than 0.006 mm.

Claims (1)

Invention Formula five A pancratum of the eye, containing the 1st two components, the first of which is mounted for movement along the axis, the second positive fixed is glued from the positive and negative lenses, it is different with the fact that, in order to expand the range of change of the focal distance, the first component made positive of two two-convex lenses glued together and a double-concave lens placed between them, while the radii of the outer surfaces of the first component are in absolute value equal to its thickness, in the second comp The positive lens is made double-convex, negative in the form of a meniscus, and the ratio of the radius of the outer surface of the first component to the focal length of the second component is 0.67-0.82. 0 five 0