Abstract: Disclosed is an image pickup lens (LN) including at least three lens blocks (BK) each equipped with a lens substrate (LS) being a parallel flat plate, and a lens or lenses (L) having a positive or negative power and being connected to at least one of an object-side surface and an image-side surface of the lens substrate (LS). In the image pickup lens (LN), a first lens block (BK1) arranged at a closest position to an object side has a positive powder, a second lens block (BK2) arranged at an image side of the first lens block (BK1) has s negative power, and predetermined conditional expressions are satisfied, whereby the image pickup lens capable of being easily produced at a low cost and having a high performance and a compact size can be provided.

Abstract: An imaging lens (LN) includes at least one lens block (BK), and an aperture stop (ape). The lens block (BK) includes parallel flat lens substrates (LS) formed of different materials, and a lens (L). In the imaging lens (LN), a first lens block (BK1) positioned closest to an object includes a first lens substrate (LS1) and a lens (L[LS1o], and a prescribed conditional expression is satisfied.

Abstract: A variable magnification optical system of the present invention and an image pickup device and a digital apparatus including this are provided with a four-component optical system of negative-negative-positive-negative arrangement, wherein a first lens group thereof includes only one negative lens as a lens having an optical power, and a third lens group thereof satisfies a conditional expression of 1.4<?3t/?3w<4 when ?3t and ?3w respectively denote image magnifications of the third lens group at a telephoto end and at a wide-angle end. The variable magnification optical system, the image pickup device and the digital apparatus having such a construction can be further downsized.

Abstract: Provided are a wide angle optical system having better optical performance, low in cost, and compact in size, an imaging lens device having the wide angle optical system, a monitor camera, and a digital apparatus. The wide angle optical system (1) has, in order from the object side to the image side, a first lens (11) having a negative optical power, a second lens (12) having a negative optical power, a third lens (13) having a positive optical power, an aperture (15), and a fourth lens (14) having a positive optical power. The wide angle optical system satisfies the conditional expression of 3<f34/f<10, where f34 is the composite focal length of the third and fourth lenses (13, 14) and f is the focal length of the entire system.

Abstract: A wide-angle optical system comprises a front lens group (11), and a rear lens group (12), with an aperture stop (13) interposed between. The front lens group (11) includes at least two negative lenses (111, 112) and at least one positive lens (113). At least one of the positive lenses included in the front lens group (11) has at least one aspherical surface. The front lens group (11) satisfies the conditional expression vdp<29 where vdp is the minimum value of the Abbe number of the positive lens(es) included in the front lens group (11).

Abstract: The present invention provides a wafer-scale lens in which a total optical length is short in comparison with an image height and astigmatism and other aberrations can be well corrected, and an optical system in which a lens element closest to the object side is thin in thickness. The optical system includes a first lens that is disposed closest to the object side and is positive in refractive power; a second lens that is disposed on the image side and has a concave surface on the object side; an i-th lens, (i?3), that is disposed closest to the image side in lenses disposed on the image side and includes an i-th lens plate and a lens element which is formed on at least either the object side surface or the image side surface of the i-th lens plate, and has a refraction index different from the i-th lens plate and positive or negative refractive power; and satisfies 0.9>Ymax/Y>0.

Abstract: Provided are a wafer scale lens, which is so short in an optical total length with respect to an image height that it can correct an aberration satisfactory, and an optical system including the wafer scale lens and having a thin lens element on the side closest to the image. The optical system includes a first lens having a positive refractive power relative to an object, and a second lens arranged on the side of the image of the first lens and having a recessed shape on the side of the object. At least one lens is arranged on the side of the second lens.

Abstract: There is provided a zoom optical system having lens elements produced with less difficulty i.e. with substantially the same skill level as the conventional arrangement, with sufficient miniaturization. The zoom optical system includes a first lens group having a negative optical power, and a second lens group having a positive optical power in the order from the object side, the distance between the first lens group and the second lens group being decreased in zooming from a wide angle end to a telephoto end. The first lens group is constituted of a negative lens element and a positive meniscus lens element. The second lens group is constituted of a biconvex positive lens element and a negative meniscus lens element.

Abstract: An imaging lens (LN) includes at least one lens block (BK), and an aperture stop (ape). The lens block (BK) includes parallel flat lens substrates (LS) formed of different materials, and a lens (L). In the imaging lens (LN), a first lens block (BK1) positioned closest to an object includes a first lens substrate (LS1) and a lens (L[LS1o], and a prescribed conditional expression is satisfied.

Abstract: An imaging lens (LN) includes at least one lens block (BK), and an aperture stop (ape). The lens block (BK) includes parallel flat lens substrates (LS) formed of different materials, and a lens (L). In the imaging lens (LN), a first lens block (BK1) positioned closest to an object includes a first lens substrate (LS1) and a lens (L[LS1o], and a prescribed conditional expression is satisfied.

Abstract: An imaging lens (LN) includes one or two lens blocks (BK), and an aperture stop (ape). The lens block (BK) includes a plane-parallel lens substrate (LS) and a lens (L) formed of different materials. In the imaging lens (LN), a first lens block (BK1) disposed at the most object-side exerts a positive optical power, and a conditional formula defined by the absolute difference between the index of refraction of a first lens substrate (LS1) and the index of refraction of a lens (L[LS1o]) contiguous with an object-side substrate surface of the first lens substrate (LS) is fulfilled.

Abstract: An imaging lens (LN) includes one or two lens blocks (BK), and an aperture stop (ape). The lens block (BK) includes a plane-parallel lens substrate (LS) and a lens (L) formed of different materials. In the imaging lens (LN), a first lens block (BK1) disposed at the most object-side exerts a positive optical power, and a conditional formula defined by the absolute difference between the index of refraction of a first lens substrate (LS1) and the index of refraction of a lens (L[LS1o]) contiguous with an object-side substrate surface of the first lens substrate (LS) is fulfilled.

Abstract: Provided is an imaging lens using a wafer scale lens which can easily be produced in a mass production. The entire optical length can be reduced without increasing a lens substrate or a lens formed on the substrate or without using a diffracting plane. The aberration can be preferably corrected. The imaging lens forms a first lens having a positive refractive power and Abbe number v1 on the object side and a second lens having a negative refractive power and Abbe number v2 on the image side of the first lens substrate. The difference between the Abbe number v1 and the Abbe number (v1?v2) is set to be a value greater than 10.

Abstract: A variable-power optical system includes, in order from an object side thereof: a first lens group with a negative optical power; a second lens group with a positive optical power; a third lens group with a negative optical power; and a fourth lens group with a positive optical power. An interval between the first lens group and the second lens group decreases when a power of the variable-power optical system varies from a wide-angle end to a telephoto end. The second lens group includes at least one aspheric surface. The variable-power optical system satisfies the predetermined conditional expressions.

Abstract: A variable-power optical system includes, in order from an object side thereof: a first lens group with a negative optical power; a second lens group with a positive optical power; and a third lens group with a negative optical power, where an interval between the first lens group and the second lens group decreases when a power of the variable-power optical system varies from a wide-angle end to a telephoto end. The first lens group comprises a negative lens and a positive lens. The second lens group consists of a positive lens and a negative lens, and includes at least one aspheric surface. The variable-power optical system satisfies the predetermined conditional expressions.

Abstract: Provided is a microminiaturized zoom optical system capable of sufficiently correcting aberration. The zoom optical system (100) includes a first lens group (101) having a negative optical power, a second lens group (102) having a positive optical power, and a third lens group (103) having a positive or negative optical power in this order from the object side. The zoom optical system is configured in such a manner that the interval between the first lens group (101) and the second lens group (102) is decreased in zooming from the wide angle end to the telephoto end. A positive lens element in the third lens group (103) or in a lens group closer to the image side than the third lens group (103) satisfies the following conditional expression: vp<40 where vp is the minimum value of the Abbe number of the positive lens element.

Abstract: A variable-power optical system includes, in order from an object side thereof: a first lens group with a negative optical power; a second lens group with a positive optical power, moving when the power of the variable-power optical system varies; and a third lens group with a positive or negative optical power. The first lens group includes two or more lenses including one positive lens and one negative lens which include at least two or more lenses made of a plastic material. The variable-power optical system satisfies the predetermined conditional expressions relating to is a focal length of the first lens, a focal length of the second lens, a composite focal length of the total optical system, and an image-forming magnification of the second lens group at a telephoto end.

Abstract: There is provided a zoom optical system having lens elements produced with less difficulty i.e. with substantially the same skill level as the conventional arrangement, with sufficient miniaturization. The zoom optical system includes a first lens group having a negative optical power, and a second lens group having a positive optical power in the order from the object side, the distance between the first lens group and the second lens group being decreased in zooming from a wide angle end to a telephoto end The first lens group is constituted of a negative lens element and a positive meniscus lens element. The second lens group is constituted of a biconvex positive lens element and a negative meniscus lens element.

Abstract: A zoom optical system has lens groups, and performs zooming by varying distances between the respective lens groups in an optical axis direction thereof. The zoom optical system has two or more lens groups having a negative optical power and a positive optical power in this order from an object side. The first lens group (Gr1) and the second lens group (Gr2) each have three or less lens elements. The second lens group (Gr2) includes a positive lens element having a refractive index of 1.7 or more. The positive lens element has at least one aspherical surface. With this arrangement, provided are a compact and superfine zoom optical system with a zoom ratio of about two to three times, an imaging lens device incorporated with the zoom optical system, and a digital apparatus loaded with the imaging lens device.

Abstract: A super-wide-angle optical system for forming an optical image of an object on an image pickup surface of an image sensing device that converts the optical image into an electrical signal is provided with, in order from the object side, a first negative lens, a second negative lens and a positive lens. The first negative lens has a meniscus shape convex to the object side. The second negative lens is positioned next to the first negative lens. The positive lens has an aspherical surface. At least one of four lens surfaces of the first and second lenses is an aspherical surface. A prescribed condition is fulfilled.