Asahi Kogaku Kogyo Kabushiki Kaisha

Asahi Kogaku Kogyo K.k.

Asahi Kogaku Kabushiki Kaisha

Asahi Optical Co., Ltd.

Satoru Tachihara

Akira Morimoto

Yuji Matsui

Takashi Okuyama

Tamihiro Miyoshi

Ryota Ogawa

Masatoshi Iwama

Yasushi Ikeda

Hideyuki Morita

Akira Ohwaki

Toshitaka Yoshimura

Hidetaka Yamaguchi

Mitsuo Kakimoto

Michio Ohshima

Jun Nonaka

Hiroaki Andoh

Koichi Maruyama

Masahiro Oono

Sadao Okudaira

Kazuyuki Takahashi

Tsuyoshi Ishikawa

Tetsuya Nakamura

Masato Noguchi

Daisuke Koreeda

Kazuo Nakamura

Yasuyuki Tejima

Kazushi Yoshida

Nobutaka Minefuji

Seijiro Tokutomi

Masao Jyojiki

Eiichi Ito

Michiro Ohishi

Shinichi Suzuki

Takayuki Itoh

Takashi Koeda

Takaomi Sekiya

Tomohiko Kanzaki

Chinari Tanaka

Tunehiko Sonoda

Katsuhiro Yoshino

Hiroaki Andon

Jun Nonoka

The stereoscopic microscope includes a common close-up optical system that faces an object, a pair of zoom optical systems that form a pair of primary image, a pair of field stops, a pair of relay optical systems that relay the primary images to form a pair of secondary images, an inter-axis distance reducing element, an image taking device and an illuminating optical system. The object light rays incident on the close-up optical system form the primary images having predetermined parallax at the field stops through the zoom optical systems. The inter-axis distance reducing element reduces the inter-axis distance of the right and left light rays. The primary images are re-imaged by the relay optical systems as the secondary images on the adjacent regions on the single image taking surface of the image taking device, respectively.

Stereoscopic microscope including zoom and relay optical systems

The optical system of the microscope includes a close-up optical system that faces an object, a pair of imaging optical systems that take object light rays passing through regions of the close-up optical system, and an illuminating optical system that guides illumination light emitted from a light source to illuminate the object. Each lens included in the close-up optical system has a semicircular shape in which one side is cut out. The close-up optical system is held in a first lens barrel, and the illuminating optical system is held in a second lens barrel. The second lens barrel is arranged in the cutout space of the close-up optical system inside the first lens barrel. A light shielding member is attached to the second lens barrel to prevent a leak of the illumination light through grooves formed on the second lens barrel.

Microscope with illuminating optical system

A chromatic aberration correcting element that is a simple lens having at least one aspheric surface the radius of curvature of which increases from the optical axis toward the periphery, at least either one of the surfaces being formed as a diffraction lens surface that consists of annular segments in steps that are shifted discretely in a direction in which the lens thickness increases as a function of the distance from the optical axis. Also, a chromatic aberration correcting device having annular segments formed in steps on either a light entrance face or a light exit face or both, the annular segments being composed of planes perpendicular to and concentric with the optical axis.

Chromatic aberration correcting element and its application

A beam projecting apparatus has a light source and a reflecting device for reflecting and rotating a bundle of light emitted from the light source for forming a reference plane. A shape converting optical system is provided in an optical path from the light source to the reflecting device for converting the bundle of light from an elliptical sectional shape to a circular sectional shape.

Beam projecting apparatus

An optical scanner including a light source which is turned ON and OFF in accordance with drawing data. A hologram deflector, made of a rotatable planar hologram disc, provided with a plurality of hologram facets through which light emitted from the light source passes, is rotated to scan an image surface with light emitted from the light source. An optical detector detects light passing in a scanning direction through at least a first reference point, for the commencement of the scanning, and a second reference point, for the completion of the scanning. A scanning time detector detects a scanning time period in which the light deflected by each hologram facet of the hologram disc, passes the first reference point and reaches the second reference point. Finally, a frequency varying device varies the frequency of the light source for each hologram facet in accordance with a unique scanning time period directed by the scanning time detector for each hologram facet.

Apparatus for correcting scanning position in optical scanner

An objective lens for an endoscope including a first lens group including one negative lens, a second lens group having a positive power, a third lens group having a negative power, and an aperture stop provided between the first lens group and the second lens group. The objective lens satisfies the relationships:

Objective lens for endoscope

An objective lens for an endoscope includes a first lens group having one negative lens, a second lens group having at least one positive lens, and a third lens group including a positive lens. The objective lens satisfies the following relationship:

For an aperture plate to be used to form dot images of a two dimensional aperture pattern by projection through an imaging optical system in a normal direction, a pattern of markings in ideal positions is projected through an imaging optical system in the reverse direction to normal imaging operations. The image of the pattern is recorded at the position of the aperture plate, and the recorded image is used as a guide to form corrected apertures in the aperture plate. Accordingly, locational errors of the dot images in the normal direction are corrected when the corrected aperture plate is used.

Method of making an aperture plate for a multibeam pattern drawing

A projector has projecting optical systems. The projecting optical systems have image formers and projecting lenses for projecting the images onto a screen. The optical axes of the projecting lenses are intersected with each other on the side of the screen. The image formers are arranged such that an image surface of each image former is coincident with the screen in accordance with Scheimpflug's rule.

Projector

An objective lens for an endoscope includes a first lens group of a positive power having a plurality of lenses, and a second lens group of a negative power. The first lens group is provided with a negative first lens located adjacent to an object to be photographed. The objective lens meets the requirements defined by (1) 0.6&lt;f.sub.F /f&lt;1.0, (2)-6.0&lt;f.sub.s /f&lt;-1.0, and (3) 1.0&lt;L.sub.D /f&lt;4.0, where f.sub.F designates a focal length of the first lens group, f.sub.s designates a focal length of the second lens group, f designates a focal length of the whole lens system, and L.sub.D designates a sum of the whole lens length and back focal distance.

An objective lens for an endoscope includes a first lens group having one negative lens, a second positive lens group having at least one positive lens, and a third positive lens group having a cemented lens consisting of one positive lens and a negative lens adhered thereto. The objective lens satisfies the requirements defined by the following relationships:

A projector has projecting optical systems which include image formers and projecting lenses for projecting the formed images onto a screen. The optical axes of the projecting lenses are intersected with each other on or very near the surface of the screen. The image formers are arranged such that an image surface of each image former is coincident with the screen in accordance with Scheimpflug's rule.

An exposure apparatus where a mask table having an exposing pattern and a work to be exposed are relative to each other movable, wherein the moving amount of the mask table is detected by a scale image formed through a projection lens system, so that even if the projection lens system has a magnification error, by optically offsetting it, the moving amount of the mask table can be detected. Thus, a more accurate control can be obtained so that a mask image can be more precisely reproduced on a work.

Exposure apparatus

A scanning pattern drawing apparatus which scans the surface of a workpiece with a light beam so that a pattern is described on the workpiece with the issued light beam being controlled on the basis of pattern drawing data stored in a pattern memory, wherein the pattern drawing apparatus is able to read many pieces of data in a short period of time even if the frequency of the timing pulses is reduced and which therefore is capable of drawing a precise pattern on a workpiece. A scanning pulse generator produces as scanning pulse in response to a predetermined amount of scanning with the light beam. The scanning pulse is converted to a plurality of resulting timing pulses, and successive parallel outputs of the timing pulses are produced after delaying by a predetermined time. The pattern drawing data is read from the pattern memory in response to the delayed timing pulses.

Scanning pattern drawing apparatus

Growing community of inventors

Tokyo, Japan

Satoru Tachihara