SU1610457A1 - Lens - Google Patents

Abstract

The invention relates to optical instrumentation and can be used to reduce the scattered light in lenses for various purposes. The aim of the invention is to reduce the effective reflection coefficient of a corrugated surface by reducing the ratio of the total area of edges on the projections of the grooves to the surface area on which the corrugation is applied. The lens contains optical elements between which the frame is corrugated on the inside, the edges of the corrugated surface facing the last lens form an angle α with the optical axis, and the edges of corrugation facing the first lens form an angle β, and angles are determined from the ratios: = ϕ _min + ψ _min / 2, β = ϕ _max + ψ _max / 2, where ϕ _min (ϕ _max ) is the smallest (largest) angle defined in the space of the corrugated surface between the optical axis and a line connecting any point of the corrugated surface with optical the point of the front surface of the first optical element bounded by its light diameter

ψ _min (ψ _max ) is the smallest (largest) angle defined in the space of the corrugated surface between the optical axis and the line connecting any point of the corrugated surface with the point of the rear focal plane of the lens optically conjugate and bounded by its linear field of view. 2 Il.

Description

The invention relates to optical instrument making and can be used to reduce the scattered light in lenses of various applications, microscopes, telescopes, binoculars, telescopes, and other optical devices.

The aim of the invention is to reduce the effective reflection coefficient of a corrugated surface by reducing the ratio of the edge area on the projections of the grooves to the surface area on which the corrugation is applied.

FIG. Figure 1 shows the optical layout of the lens; in fig. 2 - profile of ri, fleece surface.

FIG. Figures 1 and 2 show the upper and lower meridional rays 1 and 2 falling on a corrugated surface: 6 from the space of objects, the upper and lower meridional rays 3 and 4 connecting the corrugated surface with an image plane limited by the frame frame 5} are located in the plane of the lens image surface 6 on which

4 SP

grooved; edges (ledges) 7 grooves.

FIG. Figure 2 shows schematically the profile of the corrugated surface and the designation of the angles ω and J}, which are the edges of the corrugated with the optical axis. The angles fti and A are determined according to the formulas

. H mmn H min About

;

(

I min ML acr is the smallest (largest) angle defined in the space of the corrugated surface between the optical axis and the line connecting any point of the corrugated surface with the point of the front optical surface of the first optical element bounded by its optical diameter, and ((the smallest (largest) angle defined in the space of the corrugated surface, between the optical axis and the line connecting any point of the corrugated surface with the optical focus point of the rear focal plane of the lens, ennoy its linear field of view.

The device works as follows. in a way.

When the lens is illuminated from the entire front half hemisphere of the object space (which is the most severe condition from the point of view of the formation of scattered light) and if the angles of inclination of the corrugation faces applied to the inner cylindrical surfaces of the frame to the optical axis satisfy these equalities, then the light flux reflected from these faces does not fall within the linear field of the lens in the image plane. Only the luminous flux that is reflected from the edges (protrusions) of the grooves applied to the frame enters the frame window of the lens. However, the total area of these edges under a given condition for the selection of ei and A is minimal, which is ensured by an increase in the effectiveness of anti-reflection.

Claims (1)

Invention Formula A lens containing - optical elements fixed in a frame, on the inner surface of which, made cylindrical or conical and located behind the first optical element, is caused by a counter-reflecting corrugation in the form of annular or screw grooves, characterized in that reflection corrugated surface by reducing the ratio of the total  the area of the edges on the projections of the grooves to the surface area on which the corrugation is applied, the faces of the corrugated surface between the optical axis, facing the last lens , lens, make the angle Oi with the optical axis, and the edges of the corrugated, reflected in the direction of the first lens, make the angle b with the optical axis, and the angles Si and L are equal  min 0 --- -5 - /  - - Mqicc J five 0 0 whereSOC., H max is the smallest (largest) angle defined in space of the corrugated surface between the optical axis and the line connecting any point of the corrugated surface with the optical surface of the first surface of the first optical element bounded by its optical diameter} (,), 0 - the smallest (the most | 4 m ks.) Is defined in space by a corrugated axis and a line connecting any point of the corrugated surface with the rear focal plane of the lens optically coupled with its linear field see about five 50 55 Rifleia surface   // Frame pofit Q , 1 FIG. 2