DE1472188C - Telephoto lens for infrared radiation - Google Patents

Description

/ = 100; 1: 2.5 Ί + 66.04 di = 4.6 r ₂ = 61.72 / ι = 5.0 r ₃ + 41.60 d _% = 8.6

1 sheet of drawings

Claims (4)

1 2 tive for this spectral range are known, their claims: But the focal length is about according to their structure as normal achromatic lenses from two thin menisci 1. Telephoto lens for infrared radiation from SiI- equal to the focal length. Also in the case of the objective according to the zium and germanium lenses, which is characterized by the long focal length facing the long focal length, the converging grain converging lens is meniscus-shaped and made of silicon; On each component of the telesystem, they are followed by two scattering lenses made of germanium, which are flat-silicon meniscus and a scattering Germanium meniscus and between their nium meniscus, the scattering component of the facing hollow surfaces enclose the diaphragm.
Telephoto lens from a single dispersing io It is primarily characteristic of the telesystem that it consists of germanium meniscus, both of which are scattered, that the distance between the menisci ending in the long focal length have their hollow surfaces facing each other, to which the collecting components also turn and have a distance , which is between the converging meniscus of the adjacent scattering 25 and 35, preferably at 30% of the focal length. Meniscus belongs, and the scattering component 2. Telephoto lens according to claim 1, characterized in that the second negative of the telephoto lens indicates that the scattering component of the meniscus lens is formed much larger, be telephoto lens a thickness between 7 and 10, "preferably about three times as large, than the distance which preferably has about 9 ° / _{0 of} the focal length, hollow surface of this second negative meniscus from 3. Telephoto lens according to claim 1, characterized by the focal point on the image side and thus at 25 to 35 indicates that the front lens is through a 20 of the focal length, preferably at 30 ° / ". This hollow refractive powerless Meniscus is protected from silicon. area is the dominant component of the litter 4. Telephoto lens according to claim 1, 2 and 3 according to the end component. the following data on any scale, with further it is with a view to correcting the the thicknesses and distances by ± 5% of the focal off-axis image errors appropriate, the thickness of this wide, the surface powers vary by ± 10% meniscus between 7 and 10%, preferably to about can: 9% to choose the focal length so that the cut width is only small, namely between 1 and 2% of the / = 100; Focal length is 1: 2.5. :. r _x = 66.4 - For installation in movable facilities, it is d ₁ = 4.6 / i = 3.42 protective meniscus 30 advantageous, the objective through a _{superposed r 2} = 61.72. Meniscus without refractive power to protect itself from 1 ₁ = 5.0 of the converging lens made of silicon on the side of the long r ₃ + 41.60 ... Barked back focal length. This meniscus consists of d ₂ = 8.6 η = 3.42 moderately also made of silicon. / "4 + 118.6 35 The data of the system according to the invention go 1 ₂ = 2.05 from the following table; the refractive indices r ₅ -f- 193.5. apply to a wavelength of 4.26 mm: d ₃ = 4.9 η = 4.02 r _e + 72.0 1 ₃ = 30.0 r ₇ = - 7.92. d _x = 4.6 η = 3.42 protective meniscus (Z ₄ = 9.3 / 1 = 4.02 r ₈ - 26.66 J'o = 1.48 45 d ₂ = 8.6 η = 3.42 r ₄ +118.6 . * I ₂ = 2.05 . ■ ■ · r ₅ + 193.7 '4> = ⁴ > ⁹ η = 4.02 The invention relates to a telephoto lens made of 50 r _e + '72.0 _: Silicon and germanium for infrared radiation I ₃ = 30.0 between about 3 and 8 mm wavelength, which r ₇ = -7.92 would solve, with an aperture ratio of at least d _t - 9.3 η = 4.02 1: 3, preferably 1: 2.5, for the stated range achro- r _s -26.66
to be matic with a working length of 55 s' _o = 1.48 To show the sum of the overall length and back focal length, less than _^2/3 of the focal length, preferably only about In the figure, a lens according to the invention 55% of the focal length. Achromatic object shown in longitudinal section.