Fujifilm Corporation

Fuji Photo Optical Co., Ltd.

Fujinon Corporation

Ryoko Otomo

Taro Asami

Hiromitsu Yamakawa

Toshiaki Katsuma

Masao Mori

Masato Kondo

Toru Ito

Takayuki Noda

Michio Cho

Yu Kitahara

Akiko Ishii

Provided are an imaging lens, which has a small F number and in which various aberrations are satisfactorily corrected, and an imaging apparatus including the imaging lens. The imaging lens includes, in order from an object side: a first lens that has a biconcave shape; a second lens that is convex toward an image side and has a positive refractive power; a third lens that has a biconvex shape; a fourth lens that has a negative refractive power; a fifth lens that has a positive refractive power; and a sixth lens that has a negative refractive power. Assuming that L1f and L1r are paraxial radii of curvature of an object side surface and an image side surface of the first lens, Conditional Expression (1) is satisfied.0.1&#x3c;(11)/(11)&#x3c;0.8&#x2003;&#x2003;(1)

Imaging lens and imaging apparatus

An imaging lens is composed of a first lens having a negative meniscus shape with a convex surface on the object side, a negative second lens, a positive third lens, an aperture stop, a negative fourth lens, and a positive fifth lens disposed in order from the object side. The fourth and the fifth lens are cemented with an interface which is convex on the object side and has an aspherical shape. If the radius of curvature is taken as R9 and the focal length of the entire system is taken as f, the imaging lens satisfies a conditional expression given below:1.0&#x3c;9/&#x2003;&#x2003;(1).

Wide-angle imaging lens and imaging apparatus

An imaging lens substantially consists of six lenses of a negative first lens, a negative second lens, a positive third lens, a positive fourth lens, a negative fifth lens and a positive sixth lens in this order from an object side. When a curvature radius of an object-side surface of the fourth lens is Rand a curvature radius of an image-side surface of the fourth lens is Rand an Abbe number of the material of the third lens for d-line is &#x3bd;dand an Abbe number of the material of the fifth lens for d-line is &#x3bd;dthe following conditional formulas (1) and (6) are satisfied:&#x2212;0.61&#x3c;(8+9)/(8&#x2212;9)&#x3c;0.44 &#x2003;&#x2003;(1); and38.1&#x3c;&#x3bd;3+&#x3bd;5&#x3c;45.1 &#x2003;&#x2003;(6).

Imaging lens

An imaging lens substantially consists of six lenses of a negative first lens, a negative second lens, a positive third lens, a positive fourth lens, a negative fifth lens and a positive sixth lens in this order from an object side. When a curvature radius of an object-side surface of the fourth lens is R, and a curvature radius of an image-side surface of the fourth lens is R, and an Abbe number of the material of the third lens for d-line is &#x3bd;d, and an Abbe number of the material of the fifth lens for d-line is &#x3bd;d, the following conditional formulas (1) and (6) are satisfied:&#x2212;0.61&#x3c;(R8+R9)/(R8&#x2212;R9)&#x3c;0.44&#x2003;&#x2003;(1); and38.1&#x3c;&#x3bd;d3+&#x3bd;d5&#x3c;45.1&#x2003;&#x2003;(6).

An imaging lens substantially consists of six lenses of a negative first lens, a negative second lens, a positive third lens, a positive fourth lens, a negative fifth lens and a positive sixth lens in this order from an object side. When a curvature radius of an object-side surface of the fourth lens is R8, and a curvature radius of an image-side surface of the fourth lens is R9, and an Abbe number of the material of the third lens for d-line is &#x3bd;d3, and an Abbe number of the material of the fifth lens for d-line is &#x3bd;d5, the following conditional formulas (1) and (6) are satisfied:&#x2212;0.61&#x3c;(8+9)/(8&#x2212;9)&#x3c;0.44&#x2003;&#x2003;(1); and38.1&#x3c;&#x3bd;3+&#x3bd;5&#x3c;45.1&#x2003;&#x2003;(6).

An imaging lens substantially consists of six lenses of a negative first lens, a negative second lens, a positive third lens, a positive fourth lens, a negative fifth lens and a positive sixth lens in this order from an object side. An object-side surface of the second lens is concave, and an object-side surface of the third lens is concave. A predetermined conditional formula about a combined focal length of the fourth lens and the fifth lens is satisfied.

Provided is a fast image reading lens system capable of achieving compactness and satisfactorily correcting various aberrations. The image reading lens system includes, in order from an object side: a positive first lens of which a convex surface faces toward the object side; a second lens formed as a biconcave lens; a third lens formed as a biconvex lens; a positive fourth lens of which a convex surface faces toward an image side; and a negative fifth lens of which a convex surface faces toward the image side. Assuming that a focal length of the whole lens system is f, a focal length of the fourth lens is f, and a space between an image side surface of the fourth lens and an object side surface of the fifth lens on an optical axis is D, the lens system satisfies the following conditional expressions: 0.06&#x3c;D/f&#x3c;0.16, and 0.77&#x3c;f/f&#x3c;1.81.

Image reading lens system and image reading apparatus

An imaging lens is provided and includes, in order from the object side, a front group having a negative power, a stop, and a rear group having a positive power. The front group includes, in order from the object side, a first negative lens having a meniscus shape with a concave surface on an image side, a second negative lens, and a third positive lens. The rear group includes, in order from the object side, a fourth positive lens, a fifth negative lens having a meniscus shape with a concave surface on the object side, and a sixth positive lens. An Abbe number of each of the first lens, the second lens, the fourth lens, and the sixth lens at the d-line is equal to or larger than 40, and an Abbe number of each of the third lens and the fifth lens at the d-line is equal to or smaller than 40. Each lens constituting the front group and the rear group is a single lens.

Imaging lens and imaging apparatus using imaging lens

A wide-angle imaging lens is provided and includes: a first lens, a second lens, and a third lens in this order from the object side. The first lens is a negative meniscus and has a convex surface on the object side; the second lens, at least one surface of which is an aspherical surface; and the third lens is a positive lens and has a convex surface on the image side and at least one surface of the third lens is an aspherical surface. The first len is made of a material having an Abbe number of 40 or more and the third lens is made of a material having an Abbe number of 50 or more. An aperture stop is disposed between the second lens and the third lens.

Wide-angle imaging lens

A color image readout lens comprises, in order from an object side: a first group comprising a positive lens convex toward the object side and a biconcave negative lens; a stop; a second group comprising one diffractive optical element that has at least one flat surface and has a diffractive structure formed on the flat surface; and a third group comprising a biconvex positive lens and a negative lens concave toward the object side.

Color image readout lens and color image readout apparatus

An ultra wide-angle imaging lens deviceincludes, in order from an object side: a negative first lens Lhaving a meniscus shape with a convex surface directed to the object side; a negative second lens Lhaving a concave surface directed to an image side and having at least one aspheric surface; a positive third lens Lhaving a convex surface directed to the object side and having at least one aspheric surface; a stop; and a positive fourth lens Lhaving a convex surface directed to the image side and having at least one aspheric surface. The following conditional expression (1) is satisfied:&#x2212;3.2&#x3c;&#x3c;3.2&#x2003;&#x2003;(1)where L denotes a distance on an optical axis from an object side surface of the first lens to an image formation surface, and fdenotes a composite focal length of the third and fourth lenses Land L

Ultra wide-angle imaging lens device and imaging apparatus

A projection optical system is disclosed that includes six lens groups, four of which are positioned in pairs symmetrically about a stop. The second and fifth lens groups, in order from the object side, may be positioned symmetrically about the stop but are also adjustable asymetrically about the stop in order to adjust the magnification of the projection optical system. The first and sixth lens groups, in order from the object side, function to make the projection optical system substantially telecentric on both the object side and the image side, respectively. Also disclosed is a projection and light exposure apparatus that uses the projection optical system of the present invention. The projection and light exposure apparatus automatically detects the image magnification and, based on the detection result, adjusts the positions of the second and fifth lens groups Gand Gas a unit so as to maintain a specified magnification.

Projection optical system and projection and light exposure apparatus using it

A projection optical system is disclosed that includes six lens groups, four of which are positioned in pairs symmetrically about a stop. The second and fifth lens groups, in order from the object side, may be positioned symmetrically about the stop but are also adjustable asymetrically about the stop in order to adjust the magnification of the projection optical system. The first and sixth lens groups, in order from the object side, function to make the projection optical system substantially telecentric on both the object side and the image side, respectively. Also disclosed is a projection and light exposure apparatus that uses the projection optical system of the present invention. The projection and light exposure apparatus automatically detects the image magnification and, based on the detection result, adjusts the positions of the second and fifth lens groups G and G as a unit so as to maintain a specified magnification.

Growing community of inventors

Saitama, Japan

Ryoko Otomo