DE2314881C3 - Wide angle lens system - Google Patents

Description

F ₁ = -94.8

Λ ... Μ.6 = 52.3 Another advantage of the invention is that the wide-angle lens system is a compact one

Construction has. ,. ,. ,,

It is advantageous that the objective according to the invention fulfills the following conditions at the same time:

35

The invention relates to a compact wide-angle lens system with six approximately symmetrical in four Lenses arranged in groups of effects.

From US-PS 25 16 724 a wide-angle lens system has become known, which consists of six in four Action groups combined lenses. This wide angle lens system is for use developed for aerial photography. In particular, there should be a greater drop in light intensity to be avoided towards the edge of the lens. A disadvantage of this wide-angle lens system is that that undesirable distortions occur at larger angles. For example, the distortion is at an angle of 37.5 °, approximately 0.033%.

The object of the invention is to provide a compact To create wide-angle lens system in which the distortion that occurs is as low as possible.

This task is accomplished by forming the wide angle lens system with the design data solved according to the data table listed in the characterizing part of the claim.

A major advantage of the invention is that the distortion at 37.5 ° is only 0.02%. At 40 ° the distortion is only about 0.01%. The inventive design of the The wide-angle lens system was able to reduce the distortion compared to the wide-angle lens system already mentioned can be reduced to about 0.6 times. The wide-angle lens system according to the invention is characterized above all by the fact that it images practically distortion-free. It is suitable therefore particularly suitable for use in surveying equipment.

II) 0.1 <B, -n, <0.16; 0.1 F <r _t < 0.15 F,
HI) 20 <r ₄ -v ₅ <24; 0.005 <W ₁ -W ₅ <0.02,

IV) / 72.2 <Λ.2.3.4.5 < Fl ¹ ' ⁶ '

V) 0.2f <N <0.3F; r _e <0.

The subject matter of the invention is explained in more detail below. It shows

F i g. 1 the lens system according to the invention and

2 shows the characteristic aberration curves of the system.

In the lens system as shown in F1 g. 1 shows the four action groups 10, 20, 30, 40, of which the first action group 10 and the fourth action group 40 each consist of a lens LX and L6, while the second and the third action group each consist of two lenses cemented together Ll and L3 or LA and LS exist. The first lens Ll is a negative meniscus, the more strongly curved surface of which faces the image side. The second lens Ll is a negative meniscus, the more strongly curved surface of which is cemented to the more strongly curved surface of the third lens L3. This third lens L3 is itself a positive lens and together with the second lens L1 forms the overall positive effect group 20. The fourth lens LA is a positive lens, while the fifth lens LS has almost no refractive power. The lenses LA and LS are cemented to one another on their more curved surfaces and form the overall positive effect group 30. The sixth lens L6 is a negative meniscus, the more strongly curved surface of which faces the object side.

The following designations are chosen for the lens according to the invention:

F focal length of the entire system,
F _lf2 ... i combined focal length of the subsystem

of lenses 1 to i, m is the refractive index of the i-th lens for the rf line,

na refractive index for the d-ΙΛηκ, ng refractive index for the g-line,
η ABBE number of the i-th lens,
η radius of curvature of the / -th surface and dj vertex distance between surfaces j and O "+ 1) ·

Below are the numerical values of the lens of the invention and its SEIDEL coefficients reproduced:

585.51 di F = 100 Jv ₁ 1.61375 / 56.4 52.68 d ₂ 7.69 W. > "i 26.50 d ₃ 23.08 > 2 1.7440 / 44.80 r ₃ 12.27 d _t 7.69 η Jv ₃ 1.60729 / 59.4 10.77 η

-869.76 d _b -64.54

-39.80 -41.68 -25.89 -62.57

4.62

d _s 10.77 d _H 23.08

F ₁ = -94.8

23 1488 1 0 S ₂ 4th S ₃ U P. S ₅ -9.44 0.01 0.04 Y 0.07 0.55 75.24 -0.36 -0.01 I. -0.72 -0.03 -73.33 1.85 0.05 1.61 0.04 SEIDEL coefficients 1.52 1.49 -0.03 -0.40 0.01 1.81600 / 46.8 -9.14 -1.11 0.81 0.04 -0.62 1 0.16 3.12 -1.06 -0.70 0.60 1 80518/25 4 2 33.69 -0.02 0 0.01 0 ⁵ 3 -15.06 -3.32 0.33 11.07 -0.14 4th 1.45 -1.72 -0.20 -1.63 -0.21 5 5.09 -0.39 0.11 0.67 -0.21 6th -0.46 0.02 0.03 0 1.72825 / 28.5 7th IO g 9 10

In Fig. 2 are the aberrations of the invention Objectively presented in the usual way.

1 sheet of drawings

Claims (1)

Claim: Compact wide-angle lens system with six symmetrically arranged in four action groups Lenses, characterized by the following data: F = 100 fj 585.51 d _x 7.69 JiJv ₁ 1.61375 / 56.4 r _t 54.68 d ₂ 23.08
r ₃ 26.50 d ₃ 7.69 w "/ v ₂ 1.74400 / 44.8 r ₄ 12.27 ¹ p d _t 10.77 W ₃ K 1.60729 / 59.4 r ₅ -869.76 d _t 4.62
r, -64.54 d, 10.77 w ₄ / v ₄ 1.81600 / 46.8 ao r, -39.80 </ ₇ 8.46 fie / p, 1.80518 / 25.4 r ₈ -41.68 rf ₈ 23.08
r, -25.89 ^a 5 rf ₈ 10.77 w ₆ / v ₀ 1.72825 / 28.5 r ₁₀ -62.57