34results about How to "Wide angle of field" patented technology

A zoom lens system comprises, from an object side to an image side: a first lens unit; a second lens unit; a third lens unit; a fourth lens unit; and a fifth lens unit having positive refractive power, wherein: in zooming from a wide angle end to a telephoto end, the first, the second, the third, and the fourth lens units move so that an interval between the first and the second lens units is larger at the telephoto end than that at the wide angle end, an interval between the second and the third lens units is smaller at the telephoto end than that at the wide angle end, and a distance between the third and the fourth lens units varies; and a focal length of the first lens unit, and focal lengths of an entire system at the wide angle end and the telephoto end are appropriately set.

A zoom lens includes in order from object side to image side: a positive first lens unit that does not move for zooming; a negative second lens unit that moves during zooming; and a positive N-th lens unit that does not move for zooming, the N-th lens unit being arranged closest to the image side. The first lens unit includes, in order from object side to image side: a negative first sub-lens unit that does not move for focusing; a positive second sub-lens unit that moves along an optical axis during focusing; and a positive third sub-lens unit that does not move for focusing. Focal length of the first lens unit, focal length at wide angle end of the zoom lens, and lateral magnification at wide angle end satisfy predetermined conditions.

A zoom lens includes in order from object side to image side: a positive first lens unit that does not move for zooming; a negative second lens unit that moves during zooming; and a positive N-th lens unit that does not move for zooming, the N-th lens unit being arranged closest to the image side. The first lens unit includes, in order from object side to image side: a negative first sub-lens unit that does not move for focusing; a positive second sub-lens unit that moves along an optical axis during focusing; and a positive third sub-lens unit that does not move for focusing. Focal length of the first lens unit, focal length at wide angle end of the zoom lens, and lateral magnification at wide angle end satisfy predetermined conditions.

A zoom lens system comprises, from an object side to an image side: a first lens unit; a second lens unit; a third lens unit; a fourth lens unit; and a fifth lens unit having positive refractive power, wherein: in zooming from a wide angle end to a telephoto end, the first, the second, the third, and the fourth lens units move so that an interval between the first and the second lens units is larger at the telephoto end than that at the wide angle end, an interval between the second and the third lens units is smaller at the telephoto end than that at the wide angle end, and a distance between the third and the fourth lens units varies; and a focal length of the first lens unit, and focal lengths of an entire system at the wide angle end and the telephoto end are appropriately set.

An image pickup lens includes a first lens with positive refractive power having a convex object side surface, an aperture stop, a second lens with negative refractive power having a convex image side surface, a third lens with positive refractive power having a concave image side surface, a fourth lens with positive refractive power having a convex image side surface, and a fifth lens with negative refractive power as a double-sided aspheric lens having a concave image side surface near the optical axis;wherein the first lens and the second lens satisfy following conditional expressions (1) and (2);50<ν1<85  (1)20<ν2<35  (2)where ν1 represents an Abbe number of the first lens, and ν2 represents an Abbe number of the second lens, and where the second lens satisfies a following conditional expression (3);1.55<Nd2<1.70  (3)where Nd2 represents a refractive index of d-ray of the second lens.

A zoom lens including, in order from an object side, positive, negative, positive, positive, and positive lens units, or positive, negative, positive, positive, positive, and positive lens units. 1.5<L2fm / L2W<500; −30<f3 / f2<−3; and −15<f1 / f23W<−8 are satisfied, where fm=fw×(Z)1 / 2, fw represents a focal length of the entire system at a wide angle end, Z represents a zoom ratio, L2W represents an interval between a second and third lens units at the wide angle end, L2fm represents an interval between the second and third lens units at a zoom position at which an offaxial principal ray having a largest image height is highest farthest from an optical axis on a lens surface disposed on the most object side in the first lens unit in a zoom range from the wide angle end to the focal length fm, f1, f2 and f3 respectively represent focal lengths of the first, second, and third lens units, and f23W represents a combined focal length of the second and third lens unit at the wide angle end.

A zoom lens includes a first lens unit, a second lens unit, a third lens unit and a fourth lens unit that includes a 41 lens group and a 42 lens group. The 41 lens group includes a 411 lens group and a 412 lens group. A lens surface on a most image side of the 411 lens unit has a shape convex to the image side and a lens surface on the most object side of the 412 lens unit has a shape concave to the object side. A curvature radius r411 of the lens surface on the most image side of the 411 lens unit, a curvature radius r412 of the lens surface on the most object side of the 412 lens unit, and lateral magnification β3w of the third lens unit at a wide-angle end are respectively appropriately set.

A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, a third lens unit having a positive refractive power, and a rear lens group including at least one lens unit, the first lens unit is positioned closer to the object side at a telephoto end than at a wide-angle end, the third lens unit includes at least one positive lens, and a partial dispersion ratio θgF3P of a material of one positive lens in the third lens unit, Abbe's number νd3P, focal lengths fW and fT of a total system at the wide-angle end and the telephoto end respectively, a focal length f1 of the first lens unit, and a focal length f3 of the third lens unit are appropriately set.

An image pickup lens having a relatively wide angle of field with various aberrations preferably corrected and having a small F-value is achieved. The image pickup lens is composed of, in order from an object side, an aperture stop, a first lens of a biconvex shape having a refractive power, a second lens of a meniscus shape having a negative refractive power with a concave surface facing the object side near the optical axis, a third lens of a meniscus shape having a positive refractive power with a concave surface facing the object side near the optical axis, and a fourth lens of a biconcave shape having a negative refractive power near the optical axis, wherein the image pickup lens satisfies a following conditional expression (1):0.6<f1 / f<0.8  (1)where f1 represents a focal length of the first lens, and f represents a focal length of the overall image pickup lens.

A projection zoom lens having broad angle of view, high zoom ratio, and large back focus while aberrations are corrected satisfactorily, including a negative first lens group, a positive second lens group, a positive third lens group, a negative fourth lens group, a positive fifth lens group, and a positive sixth lens group from the magnification side and is telecentric on the reduction side. When zooming, the first and sixth lens groups are fixed while the second to fifth lens groups are moved and the fourth lens group is composed of one negative lens whose magnification side surface has a greater curvature in absolute value than that of the reduction side surface, and the zoom lens satisfies conditional expression (1): −12.0<f4 / fw<−5.0, where f4 is focal length of the fourth lens group, and fw is focal length of the entire lens system at the wide angle end.

An image pickup lens includes, an aperture stop, a first meniscus lens having positive refractive power with a convex surface facing the object, a second lens having positive refractive power with a concave surface facing the object, a third lens having negative refractive power with a convex surface facing the object, the both surfaces of the third lens are aspheric and having at least one pole-change point, and following conditional expressions are satisfied:TTL<3.0  (1)0.80<f1 / f<0.93  (2)0.35<bf / TTL<0.42  (3)0.70<TTL / (2IH)<0.85  (4)where TTL: a length from the surface closest to the object to an image plane, f: a focal length of an overall optical system, f1: a focal length of the first lens, bf: a length from the image-side surface of the third lens to the image plane, and IH: a maximum image height.

An image pickup lens includes a first lens having a positive refractive power with a convex surface facing the object side, a second lens having a negative refractive power with a concave surface facing the image side, a third lens having a positive refractive power with a convex surface facing the object side, a fourth lens having both sides formed as aspheric surfaces and having a negative refractive power with a concave surface facing the image side, and a fifth lens having both sides formed as aspheric surfaces and having a positive refractive power with a concave surface facing the image side, wherein the first lens and the second lens satisfy following conditional expressions (1), (2) and (3);45<ν1<90  (1)22<ν2<35  (2)2.0<ν1 / ν2 <2.6  (3)where ν1 represents an Abbe number of the first lens, and ν2 represents an Abbe number of the second lens.

In a zoom lens including a positive first lens unit, negative second lens unit, positive third lens unit, and positive fourth lens unit, the fourth lens unit includes a 41 lens group, a 42 lens group, and a 43 lens group. the lateral magnification of the third lens unit at a wide-angle end when an infinite object is focused, the focal length of the fourth lens unit, the lens configuration length of the fourth lens unit, the air interval between the 41 and 42 lens groups, the air interval between the 42 and 43 lens groups, the focal length of the 42 lens group, the average values of the Abbe constants and partial dispersion ratios of positive lens of the 42 lens group, the average values of the Abbe constants and partial dispersion ratios of negative lenses of the 42 lens group, and the like are appropriately set.

A three-dimensional image pickup optical system for forming two different images having a parallax alternately in time sequence on a single image pickup element, includes, in order from object side: a front system including a pair of negative 1f-lens units, a pair of an optical path deflecting units, and a combining unit for combining two optical paths on the same optical axis; and a rear system including a positive 1b-lens unit which does not move for magnification-varying, a lens unit moving for magnification-varying, and a stop, in which: the front system includes a pair of light quantity control units disposed in optical paths for the eyes on the object side of the combining unit, for switching left and right subject images alternately in a time sharing manner; and power arrangement of the 1f-lens units and the 1b-lens unit is set appropriately.

The zoom lens according to the present invention includes, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; a third lens unit having a negative refractive power that moves along a locus convex toward the object side during zooming from a wide angle end to a telephoto end; a fourth lens unit having a positive refractive power that moves during zooming; an aperture stop; and a fifth lens unit having a positive refractive power that does not move for zooming, in which the fourth lens unit has a lens surface having an aspherical shape with which the positive refractive power is weakened.

A zoom lens includes, in order from an object side: a first positive lens unit not moving for zooming; a second negative lens unit moving during zooming; a third positive lens unit moving during zooming; a fourth positive lens unit moving during zooming; and a fifth positive lens unit not moving for zooming. Each of the lens units includes positive and negative lenses, and satisfies 10<νp−νn<54, −1<β2w<−0.05, −5<β2t<−1, and −1<β34z2<−0.3, where νp is average Abbe constant of the positive lens of the fourth unit, νn an average Abbe constant of the negative lens of the fourth unit, β2w a magnification of the second unit at wide angle end, β2t a magnification of the second unit at telephoto end, and β34z2 a magnification of a combined lens unit including the third and fourth unit at a zoom position where the magnification of the second unit is −1.