DE2450400C3 - Telephoto lens - Google Patents

Description

5. 0.9 <rj / r ₅ <l, l group caused chromatic aberration

6. 0.008 / «/ * rf ₄ <0.015 / prevents.

-7 "" ^ i er "._ ι ι 40 The invention will now be based on the drawings

_Q. 1 ,, . , explained in more detail. It shows

8. IV ₁ -V ₂ |> J3, [V ₃ -V ₂ |> jU _{Fig χ a schemat} j _sc he sectional view of a

Telephoto lens according to the invention and

The air gap between the front and Fig. 2, 2A, 2B, 2C the correction curves of the

Condition 1 relating to the rear lens group 45 telephoto lens according to claim 1,

serves to intensify coma and astig- Fig. 3, 3A, 3B, 3C the correction curves of the

to counter matism when the telephoto ratio small telephoto lens according to claim 2,

is made. where the representations are based on the focal length / = 100

Which are related to the radius of curvature of the image-sided upper.

For this purpose 2 sheets of drawings

Claims (1)

Patent claims: · Telephoto lens made up of five lenses with a positive one Meniski lens with a convex object-side Lens surface, a concave lens and a positive meniscus with a convex object-side Lens surfaces in the front lens group as well as a negative lens with a concave lens surface on the object side and a biconvex lens through the following construction data: Table 1 T ₁ = 0.3186 r ₂ = 2.8394 r ₃ = -0.9987 r ₄ = 1.2312 r ₅ = 0.3283 f ₀ = co r ₇ = -0.1408 r _s = co r ₀ = 0.6388 Ίο = -0.4795 i /, = 0.0225 d _t = 0.0112 d ₃ = 0.0110 </ ₄ = 0.0020 d ₅ = 0.0230 d, = 0.3649 </ ₇ = 0.0100 d _a = 0.0140 i / ₀ = 0.0200 / = 1.0 1: 4.5 W ₁ = 1.48749 W ₂ = 1.7400 W ₃ = 1.52542 W ₄ = 1.51874 = 70.1 v ₂ = 31.7 v ₃ = 64.5 v ₄ = 64.5 M ₅ = 1.57309 v _s = »42.6 Sb = 0.3413 P = 0.82 where r to r _{10 are} the radii of curvature of the corresponding lens surfaces, d _x to d _{9 are} the thicknesses or air gaps of the lenses, M ₁ to W _{5 are} the refractive indices of the corresponding lenses, »! up to v ₅ the Abbe number of the corresponding lenses, / the total focal length of the lens system, fn the back focal length and P the partial ratio. 2. Telephoto lens with five lenses with a positive meniscus lens with a convex object-side Lens surface, a concave lens and a positive meniscus with a convex object-side Lens surface in the front lens group and a negative lens with a concave lens surface on the object side and a biconvex lens, characterized by the following design data: Table 2
T ₁ = 0.3224 r ₂ = 1.3884 r ₃ = -0.9223 r ₄ = 2.6366 r ₅ = 0.3329 r "= co r, = -0.1406 r ₈ = co r ₉ = 0.7064 r ₁₀ = -0.5568 d ₁ = 0.0208 d ₂ = 0.0105 d ₃ = 0.0110 d _t = 0.0020 d ₅ = 0.0230 d _t = 0.3625 d., = 0.0100 dt = 0.0140 d ₉ = 0.0250 / = 1.0 1: 4.5 W ₁ = 1.48749 w ₂ = 1.74000 W ₃ == 1.51821 w ₄ = 1.49782 V ₁ = 70.2 v ₂ = 28.3 V ₃ = 65.0 v ₄ = 66.8 w ₅ = 1.57309 v ₅ = 42.6 Sa = 0.3329 P = 0.81 3 ^ 4 therein T ₁ to r _{l0 are} the radii of curvature of the curse of the front lens relevant condition 2 is used corresponding lens surfaces, rf, to d _0, which are used to prevent overcorrection of the spherical Thicknesses or air gaps between the lenses, up to / I ₅ see aberration. Which is the radius of curvature of the the refractive indices of the corresponding lenses on the image-side surface of the third lens v, to; r ₅ the payoff of the corresponding 5 condition 3 is used for this with a small tele-ratio Lenses, / the total focal length de? Lenses- an advantageous correction of the image errors to cr- systems, f _D the back focal length and P are sufficient and make it possible to plan this surface the telephoto ratio. form what the manufacture-simplifies. Condition 4 is used for a small number of ίο Lenses a good correction for coma and To achieve sine condition, while condition 5 serves to favor the spherical aberration to correct. The invention relates to a telephoto lens. When condition 6 is met, on the one hand a the 15 insufficient correction of the spherical aberration mentioned in the preamble of claims 1 and 2 Art. Are prevented, on the other hand, the interim From US-PS 35 02 394 a telephoto lens of these spaces between the lenses is dimensioned so that none Kind of known that at a field angle of 9 ° difficulties in assembling the lenses and compact design due to low telephoto behavior. nis has a good optical correction state, ao Conditions 7 and 8 are used for correction The present invention is the task of coma, Petzval sum and chromatic aberrations, using cheap glasses a ration, in particular the condition 7 it er telephoto lens with a low telephoto ratio and a small one enables the coma to be corrected cheaply and a To create dimensions. To prevent the Petzval sum from growing, while this task is done by forming the part, the condition 8 is used for the secondary objective with the design data according to a spectrum, which the resolving power in the lower in the characteristics of claims 1 and 2, the lesser area of the image field is reduced, to be kept small, managed data tables solved. In the telephoto lens according to the present invention When developing the objects according to the invention, the differences in the dispersions The following conditional equations 30 of the corresponding positive lenses and the disperser were assumed: sion of the negative lens in the front lens group can be made large, the secondary spectrum small 1. 0.32 / << / _e <0.40 /, whereby the resolving power in the mean 2125 / "</ ·. ^'Older B ^ere i ^cn of the image field is increased. In ■ i \\ i. \ _< -n-) f 35 is achieved by using glass with low • I / 'al <.- / refractive index and lower dispersion for the 4. 0.3 <γ ₃ / γ ₄ <0.9 front lens an increase in the