SU1283692A1 - High-speed telecentric lens with extended entrance pupil - Google Patents

Abstract

The invention relates to optical instrumentation and can be used in spectral instruments. In order to increase the relative aperture and expand the spectral range of the objective lens 4, the lens is made negative, and after lens 5, a negative meniscus 6 is installed in the form of a positive meniscus with a concavity facing the object. The force positive component 1 is corrected for spherical aberration, field curvature, position chromatism, and astigmatism. Corrective negative component 2 reduces coma and compensates for residual aberrations of component 1. 1 Il. (Ls

Description

/

Primary-pupil

YU

00 CO O) C & K9

F

The invention relates to optical instrumentation, namely to lens lenses used as focusing lenses in spectral instruments (monochromators, high resolution spectrometers).

The aim of the invention is to increase the relative aperture and expand the spectral range.

The drawing shows the optical layout of the lens.

The lens consists of two components: a power positive component 1 and a corrective negative component 2. The power component 1 consists of three elements: the first element is the bottom of the tricular lens 3, the second element is a double-bent negative 50 lens 4, the third is a two-convex positive lens 5. The second correction component 2 consists of a negative meniscus 6 facing the concavity towards the image plane, a positive meniscus 7 facing the concavity towards the plane of the object, negative nisk 8, facing concavity to the plane of objects,

The entrance pupil of the system is located 94G from the first surface of the lens.

The optical power of the lens of the power component of the comput kl KT with the formulas

H.

-blJb -Aac 23

where a, b, s .-; square coefficients

equations;

V is the optical power of the first lens,

a (Jl-2B)., (n -nJnn ,,

.

2S -9, B ,,) p, p, + (2e - ,,, c (V,), + (,) n,

n., n, n - refractive indices

materials respectively 1, 2 and 3 lenses;

50

The scattering circle for a point on the axis is no more than 0.02 mm; for a beam of rays with a field angle, the scattering circle in the meridional section does not exceed 0.042 mm, and in the sagittal section it is 0.036 mm.

The relative distortion does not exceed 0.22%.

, i j ,, t j - the average dispersion of a matter - Invention Formula

alov 1, 2 and 3 lenses; S ..., - the first chromatic sum of Pr, - /

Ma Zeidel (. Determining chromatic position aberration);

55

A high-aperture telecentric lens with a remote pupil of the body, containing five single lenses, the first and third of which are two to one-fourth Zaydel sum (the field defining curvature);

- back working piece;

V: n, Gp, 7

(2)

where Vj is the optical power of the second lin

Shl.

7V,

(3)

5 0 5 0

with

0

five

0

where is the optical power of the third

lenses.

With the optimal choice of the parameters of the power component, the optical powers of the lenses of which are calculated by formulas (1) - (3), the component is corrected for spherical aberration, field curvature, position chromatism and astigmatism.

To compensate for the residual aberrations of the power component, a correction element consisting of three meniscuses is introduced into the system. The parameters of the meniscus are chosen in such a way as to minimize coma, as well as to compensate for the remaining aberrations.

The lens according to the proposed scheme has a focal length of 190 mm, a relative aperture of 1: 3, a field angle of 12 °,

Removal of the entrance pupil 180 mm, rear segment of the power component 165 mm.

The lens is corrected for a wavelength of 2.4 µm and achromatized for a spectral range from 7, 1.6 µm to 3.2 µm.

The chromatism of the position of this lens does not exceed 0.010 mm, the secondary spectrum is 0.02 mm.

The scattering circle for a point on the axis is no more than 0.02 mm; for a beam of rays with a field angle, the scattering circle in the meridional section does not exceed 0.042 mm, and in the sagittal section it is 0.036 mm.

The relative distortion does not exceed 0.22%.

A high-aperture telecentric lens with a remote pupil of the body, containing five single lenses, the first and third of which are two.

protruding, second - double-curved, after the fifth lens is set the negative of the quarter - meniscus, facing the focal meniscus, facing the concavity of the image, about the object, the fourth lens with the same the goal is enhanced by a negative, and p is the one in

the relative aperture and the form of a positive meniscus, reverberation of the spectral range conducive to the object.

Claims (1)

Claim A fast telecentric lens with a remote entrance pupil containing five single lenses, the first and third of which are biconvex, the second is biconcave, and the fourth is a meniscus facing concavity to the image, characterized in that, in order to increase the relative aperture and expand the spectral range , after the fifth lens a negative meniscus is installed, facing concavity to the object, the fourth lens is made “negative”, and the fifth is in the 5th form of a positive meniscus facing concavity to the object.