High light intensity photographic lens of the extended gauss type

Claim 1

High light intensity lens of the extended GAUSS type, consisting of at least six structural elements in contact with air, of which at least four belong to the front component situated on the object side and facing towards the longer conjugated member, followed by a GAUSS half forming the rear component on the image side and mainly built up in the normal standard manner, enclosing between them a highly dispersive biconvex central vertex gap CS in such a way that the outer surfaces belonging to the two inner negative components and in contact with air are concave towards the said air gap, in addition to which at least one of these two negative menisci is made up Of at least two individual lenses, while to ensure the maximum possible width of cut on the image side the negative meniscus N2 will be followed solely by one unequal-sided collecting element, as viewed in the direction of the shorter conjugated member, while the other negative N1 is preceded, as viewed in the direction of the object side, by at least three predominantly separate structural elements which are exposed to the air, characterized by the following dimensioning combination: a. the lens components which, as viewed in the direction of the longer conjugated member, precede the negative N1 situated on the side of the inner biconvex air space CS, contain at least two menisci (PII L and PIII L ), in each case delimited on both sides by an air space, and of positive refraction power, the sum of the surface refractive powers ( phi + phi ''+ phi + phi ''+ phi ) of these two positive menisci being greater than 1.23 times the equivalent refraction power Phi of the total lens system but less than 1.65 Phi these two positive menisci being preceded, as viewed in the direction of the object space(longer conjugated member), by at least one third positive component(PI L ), while at the same time b. the third collecting structural element (PI L ), which precedes the said two positive menisci on the object side, and which, as viewed in the direction of the light, from the object side, constitutes the front structural element, is provided, like each of the two subsequent positive menisci (PII L and PIII L ) with one surface with a convexity towards the longer conjugated member, these three surfaces having among themselves a progressively increased curvature from the side of the longer to the shorter conjugated member (the reciprocal lengths of radii thus being Rho 1 : R), while the curvature difference ( Delta , ) between the front surfaces of the collecting lenses on the object side and of the inner positive meniscus, based on the equivalent refraction power Phi 1 (as the reference unit), is selected between a lower position range limit of 0.600 on the one hand and an upper limit of 1.475 on the other, and the curvature difference ( Delta , ) (likewise based on Phi 1) between the front surface of the inner positive meniscus and that of the last collecting frontcomponent meniscus, which is the subsequent one as viewed in the direction of the light to the first negative N1, between a lower position range limit of 0.900 on the one hand and an upper limit of 1.350 on the other, in addition to which the space S preceding the said negative N1, to the added third positive (PIII - L ), is given the meniscal shape required to ensure that the limiting surfaces enclosing the said space, will be given a curvature difference ( Delta (S) ) - based on the equivalent focal length F 1 and thus on the equivalent refraction power Phi 1 - of which the absolute values are less than 0.625, but without falling below the minimum value of 0.410, while, in addition, c. the positive meniscus (PIII L ) directly preceding the negative N1 is so constructed that its hollow surface, which delimits the finite air space S enclosed in the direction of the subsequent negative N1, and which in respect of the direction of the light constitutes the rear surface, has a considerable dispersion effect, of which the surface refraction power ( phi '') is greater than 0.765 Phi , but without exceeding the value of -1.580 Phi , while at the same time the positive meniscus (PII L ) which precedes this meniscal collecting lens (L ) in the direction of the longer conjugated member, in a finite air gap, likewise has a dispersive concave rear surface which is given the dimensions required to ensure that its surface refraction power ( phi '') combined with the aforementioned dispersive surface refraction power ( phi ''), i.e. the sum ( phi ''+ phi '') of the refraction powers, is greater than -0.975 Phi , but without exceeding the value 1.950 Phi , wherein, in accordance with scientific practice, the symbol phi is adopted for the equivalent refraction power of the total lens system and the surface refraction powers of the individual lens surfaces are expressed as phi (n''- n''nR (n''- n) Rho and the lens refraction powers as phi (as the sum of the surface refraction powers phi + phi '' in the direction of the light for the front and for the particular rear lens surface which faces towards the shorter conjugated member), in addition to which, within the framework of the overall combination provided by the invention, the further dimensional rule is fulfilled according to which d. the negative value of the quotient resulting from the division of the sum of the lens refraction powers ( phi + phi ) of the inner and of the third collecting meniscus, which latter is separated from the meniscal negative N1 by an air gap and directly precedes it, by the sum of the surface refraction powers ( phi ''+ phi '') of the two rear dispersion surfaces of these two lenses, these surfaces being hollow towards the shorter conjugated member, is smaller than 1.500 but does not fall below 0.705.