SU1652956A1 - Optical system of binocular apparatus - Google Patents

Abstract

The invention relates to optical instrumentation, namely to telescopic loupes, which can be widely used in medicine. The purpose of the invention is to improve the image quality with a simultaneous increase in the removal of the exit pupil with small dimensions. Each of the channels of the optical system of a binocular instrument, the optical axes of which are placed at an angle to each other less than 90 ° C, contains a lens whose components are made single, the negative meniscus 1 of the lens faces concavity to the image space and is located in front of the two-convex lens 2 at a distance not more than 0.1 focal length of the lens, a negative meniscus 5, glued together from a bent 6 and two convex 7 lenses, is introduced in front of the two convex lens 8 and glued 7 lenses, the outer dimensions of which are equal to each other, the second component is made in the form of a two-convex lens 9. The difference in the refractive indices of materials double-bent 6 and two-convex 7 lines of negative meniscus 5 of an eyelet is not less than 0.25, and the difference of the coefficients of average dispersions is not less than 2 The transverse spherical aberration is Ј and to a point on the axis 40, the chromatism of the position for axial rays is 0.15 dptr, the increase chromatism: at the edge of the field - 1 13. on the zone - 2 st. The transverse spherical aberration of wide oblique beams does not exceed b1. 1 il. co

Description

The invention relates to optical instrumentation, in particular to telescopic magnifiers, which can be widely used in medicine.

The purpose of the invention is improving image quality with a simultaneous increase in the removal of the exit pupil with small dimensions.

The drawing shows a schematic diagram of the optical system of the binocular device and the relative position of the two channels.

Each channel of the optical system of the binocular device consists of a negative meniscus 1, facing a concavity to the space of images, and a biconvex lens 2, performing the function of the lens. The prism wrapping system consists of a half-prism 3 and a Schmidt prism 4 with a roof, each of which gives a deflection angle of 45 °. Behind the Pehan prism (3, 4), there is a negative meniscus 5 glued from biconcave 6 and biconvex 7 lenses, and two biconvex lenses 8 and 9. The exit pupil 10 of the optical system is at _t . distance convenient for observation.

The optical system of the binocular device operates as follows.

The subject is at a finite distance. The lens 1.2 creates an intermediate image of the object near the focal plane of the eyepiece 5-9. The exit pupil 10 is located at a distance of 25 mm and provides ease of observation. The pupil of the eye on the observer is combined with the exit pupil of the magnifier. For convenience of observing an object, the general enlarged image of the object coincides with the plane of objects.

The proposed binocular device is intended for surgeons during operations, so it should have small dimensions and weight. The weight of the optics of one observing system is 25 g. This is ensured by the choice of optical material and the design of the optical scheme of the device.

The binocular device is used to observe the object at a finite distance.

When moving the lens along the optical axis to the eyepiece, you can increase the distance to the object from 260 mm to infinity, while the image quality remains almost unchanged. The range of motion of the lens is about 10 mm. This property of the proposed optical system makes it possible to use the device visually impaired with visual acuity of 0.1-0.06 for viewing objects at different distances.

The exit pupil of the optical systems! .. is located at a distance of 25 mm, which makes it possible to use the device with glasses or contact lenses. This is especially important for people with complex vision correction.

The entrance pupil of the binocular device is located near the lens 1.2, so it is necessary to correct the spherical aberration, coma and the chromaticity of the position in it. To correct these aberrations, the lens 1, 2 is made of two lenses: a negative meniscus 1, facing a concavity to the image space, and a biconvex lens 2. The distance between the lens components was chosen experimentally. Each optical branch is a low magnification microscope. In the lens

1.2 microscope entrance pupil is at infinity.

The eyepiece contains a negative meniscus 5 having the same outer radii, which ensures the correction of the curvature of the image and simplifies the manufacturing technology of this component.

The specified component of the eyepiece is glued from biconcave 6 and biconvex lenses 7, the difference in the refractive indices of which is not less than 0.25 and the difference in the coefficients of the average dispersions is not less than 40. This ensures correction of image curvature, astigmatism and chromatic aberration, especially chromatic aberration.

The use of negative meniscus 5 in the eyepiece provides a small front focal segment. In this design, the front focal plane of the eyepiece, in which an intermediate image of the object is obtained, is located between the Pehan prism (3, 4) and the eyepiece (Sf - -1.5 mm). A grid can be spread in the plane of the intermediate image, which makes it possible to carry out measurement work.

The use of two biconvex lenses 8 and 9 in the eyepiece provides correction of spherical aberration on the axis and in wide inclined beams with a large exit pupil Sp - 25 mm.

As a prism wrapping system, a Pehan prism with a roof (3.4) is used, which has a long stroke with a small distance between the input and output faces.

By way of example, we calculated ogtical circuits of two binocular observation devices with the following characteristics:

J 652956

Magnification, multiple Linear field, mm Exit pupil diameter, mm Removal of the exit

4.0 6.0

57.0 40.0

4.0

25.0 pupils, mm

Front working segment, mm Length of the optical system, mm Transverse spherical points on the axis ~ 40 ¹ ', position chromatism for axial rays is -0.15 diopters.

Image curvature across the field: y = -27.0 mm. C = 0.045 diopters, L · ¹ = 1.78 diopters: • y "-19.0 mm, C = 0.368 diopters, Ls' = 0.961 diopters.

Chromatism of increase: at the edge of the field 1Ί3, at the zone - 2 ^ 6 ¹¹ . The transverse spherical aberration of wide inclined beams does not exceed 6 ¹ .

260,0

245.0

59.0 aberration for

75.0

Claims (1)

Claim An optical system of a binocular device containing two channels, the optical axes of which are placed at an angle to each other of less than 90 ^υ , and each channel is made in the form of a lens including a biconvex lens and a negative meniscus, a prism wrapping system and an eyepiece, the first component of which is a biconvex lens, and the second component is positive, characterized in that, in order to improve image quality while increasing the exit pupil extension at small dimensions, the object components in each channel The lenses are single, the negative meniscus of the lens is convex to the image space and is located in front of the biconvex lens at a distance not exceeding 0.1 f _O 6. and in front of the biconvex lens of the eyepiece, a negative meniscus is glued from the biconcave and biconvex lenses, the outer radii of which are made equal friend, while the second component of the eyepiece is made in the form of a biconvex lens, and the difference in the refractive indices of the materials of the biconcave and biconvex lenses relative to the meniscus eyepiece is less than 0.25 and the difference in average coefficients of dispersions of at least 40, where f ₀ 6 - lens focal distance.