Fujifilm Corporation

Fuji Photo Optical Co., Ltd.

Fujinon Corporation

Tomoyuki Baba

Masaru Amano

Masanao Kawana

Michio Cho

Chikara Yamamoto

Yukiko Nagatoshi

Akiko Nagahara

Takeshi Kamiya

Kimiaki Nakazawa

Kenji Suzuki

Hitoshi Miyano

Hideo Kanda

Kenzo Sado

An objective optical system for an endoscope consisting of, in order from an object side toward an image side: a front group having negative focal power; an aperture stop; and a rear group having positive focal power, wherein: the front group includes only three lenses, which consist of, in order from the object side toward the image side: a first lens having negative focal power; a second lens having negative focal power; and a third lens having positive focal power, the rear group includes only three lenses, which consist of, in order from the object side toward the image side: a fourth lens having positive focal power; a fifth lens having positive focal power; and a sixth lens having negative focal power, the second lens and the third lens are cemented to each other, and the fifth lens and the sixth lens are cemented to each other.

Objective optical system for endoscope and endoscope

An objective lens for an endoscope includes only four lens groups as lens groups, and the four lens groups consist of a negative first lens group, a positive second lens group, a negative third lens group, and a positive fourth lens group that are arranged in this order from an object side. The first lens group is fixed and the second and third lens groups are moved during focusing on an object positioned at the nearest point from an object positioned at the farthest point. The objective lens for an endoscope satisfies a predetermined conditional expression related to a focal length of an entire system and a focal length of the third lens group.

Objective lens for endoscope and endoscope

An objective optical system for an endoscope consists of, in order from an object side, a negative front group, an aperture stop, and a positive rear group. The front group includes, in order from the object side, only a negative first lens and a cemented lens formed of a negative second lens and a positive third lens cemented to each other, as lenses. The rear group includes, in order from the object side, only a positive fourth lens and a cemented lens formed of a positive fifth lens and a negative sixth lens cemented to each other, as lenses. The objective optical system for an endoscope satisfies predetermined conditional expressions.

Objective optical system for endoscope and endoscope including two lens group of &#x2212;+ refractive powers having sixth lenses of &#x2212;&#x2212;+++&#x2212; refractive powers

An objective lens for an endoscope consists of a negative front group, an aperture stop, and a positive rear group that are arranged in this order from an object side. The front group includes only a negative first lens as a lens. The rear group includes only four lenses that consist of a positive second lens, a positive third lens, a fourth lens, and a fifth lens arranged in this order from the object side, as lenses. The fourth lens and the fifth lens have refractive power having signs different from each other and are cemented to each other. Conditional expression determined in advance about the focal lengths of the second lens and the rear group is satisfied.

Objective lens for an endoscope and endoscope

The objective optical system for an endoscope includes a negative front group, an aperture stop, and a positive rear group that are arranged in this order from an object side. The front group includes only a cemented lens in which a negative first lens, a negative second lens, and a positive third lens are cemented in this order from the object side, as a lens. The rear group includes only a cemented lens in which include a positive fourth lens, a positive fifth lens, and a negative sixth lens are cemented in this order from the object side, as a lens. Conditional expressions are satisfied.

A head-up display device is improved in performance by a reduction in size and the satisfactory correction of optical aberration. A head-up display device includes a projection optical system that projects an image displayed on an image display surface to a reflective optical surface disposed at a position facing an predetermined observation position of an observer and allows the observer to visually recognize the enlarged image as a virtual image. In a case in which an optical path, which extends from a center of the image display surface and reaches a center of an eye box, is referred to as an optical axis, the projection optical system includes a first mirror having negative power near the optical axis and a second mirror having positive power near the optical axis in this order from the image display surface and Conditional Expressions (1) and (2) are satisfied.

Head-up display device

A head-up display device is improved in performance by a reduction in size and the satisfactory correction of optical aberration. A head-up display device includes an image display surface that displays an image, a reflective optical surface that is disposed at a position facing an predetermined observation position of an observer, and a projection optical system that projects the image displayed on the image display surface to the reflective optical surface disposed at the predetermined observation position and allows the observer to visually recognize the enlarged image as a virtual image. In a case in which an optical path, which extends from a center of the image display surface and reaches a center of an eye box, is referred to as an optical axis, the projection optical system includes a first mirror and a second mirror in this order from the image display surface and Conditional Expression (1) is satisfied.

A head up display apparatus includes: a first mirror having power; a second mirror having power; and a light shielding member provided with an aperture. The aperture is provided between an image display surface and the second mirror. Display light which is output from the image display surface is reflected by the first mirror, the second mirror, and the first mirror in this order, and reaches a front windshield (image reflection surface) by passing through the aperture.

Head up display apparatus

A projection lens includes a compound aspherical lens in which a resin layer is formed on a surface of a glass lens and a lens surface of the resin layer on the air contacting surface side has an aspherical shape. If the glass transition temperature of the resin layer is taken as Tg and its unit is taken as &#xb0; C., Tg of at least one of the resin layers is 150&#x3c;Tg&#x3c;280. The projection lens is configured to satisfy a given conditional expression with respect to the at least one of the resin layers.

Projection lens and projection display apparatus

An objective lens for an endoscope consists of, in order from the object side, a negative front group, an aperture stop and a positive rear group. The front group consists of, in order from the object side, a negative first lens and a cemented lens of a negative second lens and a positive third lens cemented together. The rear group consists of, in order from the object side, a positive lens and a cemented lens of a positive lens and a negative lens cemented together. The objective lens for an endoscope satisfies predetermined conditional expressions.

A projection-type display apparatus includes a light source unit, a first optical system that rays from the light source unit enter, a second optical system that rays from the first optical system enter, an image display device that rays from the second optical system enter, and a projection lens that magnifies and projects an optical image formed by rays that have been optically modulated by the image display device onto a screen. The second optical system is configured to pass again the rays that have been output from the image display device, and to make the rays enter the projection lens. The first optical system includes at least one reflective optical element, and the second optical element consists essentially of two positive lenses.

Projection-type display apparatus

An imaging lens consists of a front group having positive refractive power as a whole and a rear group in this order from an object side. The front group consists of three positive lenses, a negative lens with its concave surface facing an image side, a positive lens with its convex surface facing the object side, a negative lens with its concave surface facing the image side, a stop, a negative lens with its concave surface facing the object side and plural positive lenses in this order from the object side. The rear group has positive refractive power and consists of a positive lens and a negative lens in this order from the object side.

Imaging lens and imaging apparatus

An optical system consists essentially of, in order from the magnification side, a first lens having a positive refractive power with a convex surface on the magnification side, a second lens having a negative refractive power, a third lens having a negative refractive power, a fourth lens having a positive refractive power, a fifth lens having a positive refractive power, and a sixth lens having a positive refractive power, wherein the following conditional expressions (1) and (2) are satisfied:0.17&#x3c;2/&#x3c;0.80&#x2003;&#x2003;(1)&#x2212;60&#x3c;&#x3bd;1&#x2212;&#x3bd;2&#x3c;&#x2212;15&#x2003;&#x2003;(2)where

Optical system and optical apparatus

In a projection optical system that projects an image displayed on an image display device arranged on a reduction-side conjugate plane onto a magnification-side conjugate plane, as a magnified image, the projection optical system includes a refractive optical system and a reflective optical system having negative refractive power in this order from a reduction side. Further, the following conditional formula (1) is satisfied:+2&#x3c9;min/&#x3c9;max&#x2266;1.01&#x2003;&#x2003;(1).

Projection optical system and projection-type display apparatus

In a projection optical system that projects an image displayed on an image display device arranged on a reduction-side conjugate plane onto a magnification-side conjugate plane, as a magnified image, the projection optical system includes a refractive optical system and a reflective optical system having negative refractive power in this order from a reduction side. Further, the following conditional formula (1) is satisfied:&#x2212;0.0015&#x2266;(1/tan(&#x3c9;max)&#x2212;0.16)&#xd7;(&#x3b8;L/&#x3b8;M&#x2212;0.27) &#x2003;&#x2003;(1).

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Saitama, Japan

Tomoyuki Baba