Pentax Corporation

Ricoh Imaging Company, Ltd.

Ricoh Company, Ltd.

Hoya Corporation

Yokogawa Electric Corporation

Minoru Murayama

Hiroshi Tamura

Fumio Watanabe

Masaaki Taguchi

Takayuki Hamada

Shigeru Shibasaki

Tatsuhiko Takahashi

An imaging lens system includes a first group having positive power and a second group having positive power disposed in that order from an object side to an image. The first group includes a first sub-group and a second sub-group. The second group includes a third sub-group, a stop, and a fourth sub-group. Conditional expressions (1), (2), and (3) below are satisfied:0.07<f2/f1<0.4  (1);0.45<f2/f2a<0.7  (2);and1.05<f/R1aN<1.55  (3)where

Imaging lens system and imaging apparatus incorporating the same

An imaging lens system includes a first group having positive power and a second group having positive power disposed in that order from an object side to an image. The first group includes a first sub-group and a second sub-group. The second group includes a third sub-group, a stop, and a fourth sub-group. Conditional expressions (1), (2), and (3) below are satisfied:0.07&#x3c;2/1&#x3c;0.4&#x2003;&#x2003;(1);0.45&#x3c;2/2&#x3c;0.7&#x2003;&#x2003;(2); and1.05&#x3c;1&#x3c;1.55&#x2003;&#x2003;(3)

A finder optical system is achieved in which object images can be more easily observed. A finder optical system includes an image-erecting member, which erects an object image formed by an objective optical system, provided on an optical path from the object side toward an eyepiece side, wherein the image-erecting member is formed as a penta roof prism provided with a first reflection surface and a second reflection surface, which define a roof reflection surface that reflects an incident light bundle emanated from the object, and the first reflection surface and the second reflection surface are configured as total-reflection surfaces that totally reflect the light bundle including the object image.

Finder optical system

An eyepiece optical system is achieved that is suitable for an object image displayed on a miniaturized image display device and can magnify the object image to a high magnification ratio, the distance to the eyepoint is long while achieving a wide apparent visual angle at a short focal length, various aberrations can be favorably corrected while achieving a superior optical quality, and the pupil diameter can be enlarged. The eyepiece optical system includes a first lens element having a meniscus shape with a concave surface on the object side, a positive second lens element, a negative third lens element, and a positive fourth lens element, in that order from the object side toward the eye side.

Eyepiece optical system

A zoom lens system includes a positive first lens group, a negative second lens group, a third lens group including at least one positive lens element or one negative lens element, a positive fourth lens group, and a negative fifth lens group, in that order from the object side. At least the first, second, fourth and fifth lens groups are moved during zooming from the short to long focal length extremities, and the following conditions (1) and (2) are satisfied:&#x2212;6.5&#x3c;1/5&#x3c;&#x2212;4.6&#x2003;&#x2003;(1),and&#x2212;1.2&#x3c;3&#x3c;0.7&#x2003;&#x2003;(2),wherein f, fand fdesignate the focal lengths of the first and fifth lens groups, respectively, and fw designates the focal length of the entire zoom lens system at the short focal length extremity.

Zoom lens system

An endoscope illumination optical system includes a surface light source, a positive first lens element, a positive second lens element, in this order from the surface light source. The endoscope illumination optical system satisfies the following conditions:0.40&#x3c;&#x3c;0.53&#x2003;&#x2003;(1)0.40&#x3c;0.5&#xb7;&#xb7;&#x3b8;&#x3c;0.56&#x2003;&#x2003;(2)

Endoscope illumination optical system

A scanning objective lens for scanning on an observation target with light emitted from an exit end face of an optical fiber moving on a curved plane formed to be convex on an objective lens side, including first and second lens groups each having a positive power, wherein the first lens group and the second lens group are arranged in this order from the optical fiber's exit end face side, and the scanning objective lens satisfies conditions:0.60&#x3c;1/2&#x3c;1.25&#x2003;&#x2003;(1); and0.95&#x3c;|11|&#x3c;2.50&#x2003;&#x2003;(2)

Scanning objective lens, scanning probe and scanning endoscope

An endoscope objective lens system includes a negative front lens group, a diaphragm, and a positive rear lens group, in this order from the object. The negative front lens group includes one lens element, or a plurality of non-cemented lens elements; and the most object-side lens element is constituted by a negative lens element. The positive rear lens group includes a plurality of non-cemented lens elements; and at least one negative lens element is provided in the positive rear lens group.

Endoscope objective lens system

An endoscope objective optical system includes a negative first lens group, a positive second lens group, a positive third lens group, and a negative fourth lens group, in this order from the object. The positive second lens group and the positive third lens group are arranged to move while the object distance is varied without changing the overall length from the first lens group to an imaging plane. Due to this arrangement, the focal length of the endoscope objective optical system is varied while maintaining an in-focus state.

Endoscope objective optical system

A panel instrument apparatus of reduced size, comprising a printed circuit board on which light emitting elements and switches are mounted, and a panel cover to the rear of which the front face of the printed circuit board is attached. The panel cover comprises reflecting holes arranged in positions corresponding to the light emitting elements on the printed circuit board to guide light from the light emitting elements to the surface of the panel cover; and furthermore comprises resilient links and coupled thereto keys which are located in positions corresponding to the switches on the printed circuit board.

Panel instrument

A casing assembly for electronic equipment comprising a printed circuit board on which an exothermic electronic component is mounted, a casing for covering the printed board, and a base for attaching the casing to a wall body or a rail. The base is of a high heat conductive material and has a planar structure which results in a large contact area between it and the wall body or rail. A high heat conductive plate like cushioning member made of an electrically insulative material is interposed between the board and the base in contact therewith. The heat generated in the electronic component is released through the printed board and lead wires and through the cushioning member and the base to the wall body or rail. Preferably, where the casing is attached to the rail, a guide latch member and a pressure latch member are attached to the base. Where an auxiliary printed board is provided in addition to the printed board, the base, the printed board, the auxiliary frame and the auxiliary printed board are stacked in that order and covered with the casing. Where a programmer is attached to the casing, provision is made for attaching in either the horizontal or vertical direction. Where the functions of a basic module is insufficient, extended modules may be connected.

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Tokyo, Japan

Minoru Murayama