SU1755244A1 - Stage lens - Google Patents

Abstract

Use: observation at various magnifications. Summary of the Invention: Observation through the peripheral part of the ophthalmic 3 and collective 2 lenses is realized with an increase of 2.5x. When viewed through the central part, lenses 4 and 1 are included in the work, which allows an increase of 5x. 1 il.

Description

The invention relates to optical instrumentation, and more specifically to loops, and can be used in cases where the object is required to be viewed at different magnifications, for example, when performing preparative work.

Magnifiers are known, consisting of one or several lenses of discrete or smoothly changing magnification.

These devices are usually either fixed on a tripod, or the researcher holds the device in his hands. At the same time, in order to obtain different magnifications, or several loupes are used, or lens movement is required to switch from one magnification to another.

A magnifying glass is known, containing a collective and ophthalmic flat-convex lenses that are convex to each other. Such a magnifying glass makes it possible to observe at a fixed magnification.

The purpose of the invention is to provide two magnification values without refocusing.

The goal is achieved by the fact that in a magnifying glass containing a collective and ophthalmic flat-convex lenses facing outwards, a convex-flat lens with a diameter smaller than the diameter of the collective lens is installed coaxially with the collective lens a flat-bent lens, the diameter of which is less than the diameter of the ophthalmic lens, while the point of the front focus of the magnifying glass is aligned with the point of the front focus of the system of collective and ophthalmic lenses.

The drawing shows the optical layout of the proposed pre-loop loupe.

Magnifier consists of located along the course of the lens 1-4. Positive flat convex lenses 2 and 3 constitute a magnifying glass with an increase of FI, a front focal length S FI. Positive flat-convex lenses 1–3 and negative flat-concave lenses 4 constitute a magnifying glass with increasing F2, the front focal length of which is S F2

In this case, S F2 S FI + di, where di is the thickness along the axis of the lens 1.

Magnifier works as follows.

The object is located in the front focal plane of the lees 2 and 3, which constitute a magnifying glass with an increase in FL. A parallel beam of beams hits the observer’s eye;

WITH

ate

Yu

four

Peace picture on the retina. At small magnifications and dimensions of a magnifying glass corresponding to the eye base, binocular observation can be made.

In order to observe an object with an increase in F2, a beam of rays formed by lenses 1 - 4 must penetrate into the eye of the observer.

Example. Magnifier with an increase of Ft 2.5x and Fa 5x

Lens parameters:

P 28,3

G2 oo

G3 "

di 10 d2 0 03 - 20 u 1.65 P2 1.0 pz 1.65 G4 -130.0 p 130.0 rg e

 s

re 23,0 d4 1 ds 20 de 0

P4 1.0 P5 1.65

ne 1.0

P7 1.65

The magnifying glass has: f 52 mm; Sp, -77 mm; Fa

Fi

0

five

0

five

0

Parameters of lenses constituting a magnifying glass with 2.5x: r3 °° r4 -130.0, guv 130.0

Г6 °°

d3 20

, 0

ds 20

pz 1.65

 1.0

ns 1.65

G 100mm; SFI -87 mm.

The use of the proposed loupe as compared with the known one makes it possible to observe the object with a single instrument at two magnifications without refocusing.

Claims (1)

Invention Formula A preparative loupe containing collective and ophthalmic flat-convex lenses convex to each other, characterized in that, in order to provide two magnification values without refocusing, a convex-flat lens with a diameter smaller than the diameter of the collective lens is installed coaxially with the collective lens , behind the ophthalmic lens, a flat-bent lens is installed coaxially with it, the diameter of which is smaller than the diameter of the ophthalmic lens, while the point of the front focus of the magnifying glass is aligned with the point of the front focus of the system of collective th and ocular lenses.