Optically compensated loom type optical objective

Claim 1

A VARIABLE FOCAL LENGTH OPTICAL OBJECTIVE OF THE ZOOM OPTICALLY COMPENSATED TYPE HAVING A RANGE OF FOCAL LENGTH VARIATION OF ABOUT 3 AND HAVING A RELATIVE APERTURE OF F/1.0, SAID OBJECTIVE BEING CORRECTED IN A SUPERIOR MANNER FOR SPHERICAL AND CHROMATIC ABERRATIONS, SAGITTAL AND TANGENTIAL ASTIGMATISM, COMA, AND FIELD CURVATURE, SAID OBJECTIVE BEING COMPOSED OF TWO SPACED LENS GROUPS BETWEEN WHICH A DIPHRAGM IS INTERPOSED, THE FRONT LENS GROUP NEAREST TO ENTRANT LIGHT COMPRISING A MOVABLE FRONT DOUBLET LENS WHICH IS COMPOSED OF A FRONT DOUBLE CONVEX LENS ELEMENT DESIGNATED I IN CONTACT WITH A REAR NEGATIVE MENISCUS LENS ELEMENT DESIGNATED II, THE GROUP FURTHER COMPRISING A STATIONARY REARWARDLY SPACED DOUBLE CONCAVE SINGLET LENS DESIGNATED III, A MOVABLE PLANO CONVEX SINGLET LENS AT DESIGNATED IV WHICH IS COUPLED TO SAID DOUBLET LENS AT A CONSTANT DISTANCE THEREFROM AND MOVABLE THEREWITH TO VARY THE FOCAL LENGTH OF SAID OBJECTIVE, AND LASTLY COMPRISES A REARWARDLY SPACED NEGATIVE MENSICUS SINGLET LENS DESIGNATED V, THE REAR LENS GROUP COMPRISING THREE POSITIVE MENISCUS SINGLET LENSES DESIGNATED VI, VII, AND VIII SPACED FROM EACH OTHER AND FROM A REARWARD PLANO CONCAVE SINGLET LENS DESIGNATED IX, AND SPACED REARMOST THEREFROM IS A DOUBLE CONVEX SINGLET LENS DESIGNATED X, THE VALUES OF THE LENS PARAMETERS FOR ONE SPECIFIC FORM OF THE OBJECTIVE BEING GIVEN SUBSTANTIALLY IN THE TABLE OF MATHEMATICAL STATEMENTS HEREBELOW WHEREIN R1 TO R19 REPRESENT THE RADII OF THE SUCCESSIVE LENS SURFACES, THE MINUS (-) SIGN BEING APPLIED TO THOSE SURFACES WHOSE CENTERS OF CURVATURE LIE ON THE ENTRANT SIDE OF THEIR VERTICES, THE AXIAL THICKNESSES OF THE SUCCESSIVE LENS ELEMENTS I TO X BEING DESIGNATED T1 TO T10, THE INTERLENS AXIAL AIR SPACES BEING DESIGNATED S1 TO S9, S4 AND S5 LYING ON EITHER SIDE OF SAID DIAPHRAGM, F DENOTES THE EQUIVALENT FOCAL LENGTH OF SAID REAR LENS GROUP, AND ND AND V REPRESENT THE REFRACTIVE INDEX AND ABBE NUMBER RESPECTIVELY OF THE GLASSES FROM WHICH SAID LENS ELEMENTS ARE MADE,