Canon Kabushiki Kaisha

Kazuyuki Kondo

Tadao Hayashide

Nobuyuki Tochigi

Takeyoshi Saiga

Kazuhiko Matsuoka

Shinichi Arita

Takashi Suzuki

Takayuki Sugiyama

Haruo Tsunoi

Takahiro Mori

Makoto Tanaka

Kazumi Kimura

Jun Koide

Takehiko Nakai

Hidekazu Shimomura

Masamichi Tateoka

Tokihide Ebata

Takeshi Yamawaki

Michitaka Setani

Toshio Takahashi

Motomu Fukasawa

Hidetoshi Tanaka

Yukio Takemura

Hidekage Sato

Kanji Yano

Takeshi Kuwayama

Kazushi Kitajima

Miho Sugiyama

An object is to provide an imaging optical system having a very simple structure that can read image while maintaining excellent image quality without suffering from significant asymmetrical aberrations. An imaging optical system for image reading is adapted to form an image of image information on a surface of an original onto a line sensor while changing a relative position of the original surface and the line sensor to allow the line sensor to read the image information. The imaging optical system includes two off-axial reflecting surfaces, and the two off-axial surfaces are a plus deflecting surface and a minus deflecting surface, or a minus deflecting surface and a plus deflecting surface disposed in the mentioned order from the original surface side, where an off-axial reflecting surface that deflects a reference axis beam clockwise is defined as a minus deflecting surfaces and an off axial reflecting surface that deflects the reference axis beam anticlockwise is defined as a plus deflecting surface.

Image optical system and image reading apparatus equipped with same

An image reading apparatus includes an integral scanning optical unit in which a light source device for illuminating an original placed on an original table, a plurality of mirrors for reflecting a light beam from the original and an imaging optical system for imaging the light beam reflected by the mirrors, upon a reading device, are integrally accommodated, wherein at least one mirror is so configured that the light beam is incident thereon twice or more, wherein, in a sub-scan section, reflection surfaces of the mirrors are disposed in a space at an original-reading-position side of a light entrance surface of the imaging optical system, and wherein the reflection surface of a mirror disposed at a position optically closest to the light entrance surface of the imaging optical system is placed at a position furthermost from the original table with respect to a direction of a normal thereto, as compared with the reflection surfaces of the remaining mirrors.

Image reading apparatus

An object is to provide an imaging optical system having a very simple structure that can read image while maintaining excellent image quality without suffering from significant asymmetrical aberrations. An imaging optical system for image reading is adapted to form an image of image information on a surface of an original onto a line sensor while changing a relative position of the original surface and the line sensor to allow the line sensor to read the image information. The imaging optical system includes two off-axial reflecting surfaces, and the two off-axial surfaces are a plus deflecting surface and a minus deflecting surface, or a minus deflecting surface and a plus deflecting surface disposed in the mentioned order from the original surface side, where an off-axial reflecting surface that deflects a reference axis beam clockwise is defined as a minus deflecting surfaces and an off-axial reflecting surface that deflects the reference axis beam anticlockwise is defined as a plus deflecting surface.

Obtained are an imaging optical system having a simple structure in which imaging position deviation due to deformation caused by a weight of an off-axial optical element is reduced and an image reading apparatus using the same. According to an imaging optical system for image reading, image information on an original surface is imaged on a sensor, and is read by the sensor. The imaging optical system includes reflection-type off-axial optical elements, each of which has an outer shape whose lengths in directions orthogonal to each other are different from each other and whose thickness is smaller than a length of the outer shape in a short-direction thereof and is made of a resin material. The plurality of off-axial optical elements are disposed such that mirror surfaces thereof are opposed to each other and constructed to satisfy a conditional expression.

Imaging optical system and image reading apparatus using the same

To provide a compact imaging optical system in which occurrence of an asymmetrical aberration is reduced and the optical performance is not deteriorated significantly by constituting the system by off-axial reflection surfaces, and an image reading apparatus using the same. The imaging optical system of the present invention is characterized in that, in the imaging optical system for imaging image information of an object surface on a line sensor, all of a plurality of reflection surfaces existing in an optical path from the original surface to the line sensor are off-axial reflecting surfaces.

Imaging optical system and image reading apparatus

Imaging optical system and image reading apparatus including four, free-form shaped, resin off-axis reflective elements

A zoom lens comprises, from the object side to the image side, a first lens group, a second lens group, and a rear group including one or more lens groups, where the first and second lens groups can move at the time of zooming, and wherein the first lens group comprises, from the object side to the image side, a first lens of negative refractive power, and a second lens of positive refractive power.

Zoom lens and imaging apparatus having the same

A color image reading apparatus comprises at least three line sensors arranged at regular intervals along the main scanning direction, an imaging optical system for focussing a light beam on the line sensors, and a diffraction grating for separating a light beam coming from a color image into a plurality of light beams having respective wavelengths different from each other. The imaging optical system includes at least one lens and the optical axis of the lens is eccentrically disposed relative to that of the optical system as a whole so as for the plurality of light beams to be focussed on the respective line sensors.

Color image reading apparatus

When an image scanner scans an image recorded on an advanced photo system&trade; film, it determines spectral transmittance of a portion of the film, which is not exposed but developed, then sets parameters, such as masking parameters and &ggr; correction parameters, to be used in image signal processes on the basis of the spectral characteristics. Thereafter, the image is read by a CCD and image data is outputted. The film scanner applies the image signal processes to the image data using the parameters set in accordance with the spectral transmittance.

Image read method for performing image signal processes complying with the color of a reference portion of a recording medium, and image read apparatus adopting the method

An imaging lens is used in image reading and adapted to image information of an original on a reading device. In the imaging lens at least one surface out of a plurality of surfaces forming the imaging lens has refracting power rotationally asymmetric with respect to the optical axis.

Imaging lens and image reading apparatus using it

Transmitted light from a transmitting original recording medium based on light from a first light source which emits light in at least the visible light range is introduced to a solid imaging element via an infrared cutout filter. Image information recorded on the transmitting original recording medium is read based on signals obtained from the solid imaging element. Transmitted light from a transmitting original recording medium, based on light from a second light source, which emits light only in the infrared range, is introduced to the solid imaging element without passing through the infrared cutout filter. Defect information of the recording medium itself is read based on signals obtained from the solid imaging element, so that the read defect information can be removed from the read image information. This enable the recorded image on the film to be read in a suitable manner.

An image reading apparatus comprises a light source for illuminating an original, an imaging optical system for forming an image of the illuminated original on the focal plane of the system, and a sensor unit arranged in front of the focal plane. At least two infrared cut filters are arranged on the optical path between the light source and the sensor unit. Those infrared cut filters show respective spectral characteristics that are different from each other. The imaging optical system typically comprises a plurality of lenses and the infrared cut filters are arranged on at least two of the respective surfaces of the lenses.

Imaging optical system and original reading apparatus

The invention discloses an image reading apparatus in which a linear image sensor is provided in the vicinity of an imaging optical system and the main scanning operation is achieved by electronic scanning of the linear image sensor in the longitudinal direction thereof while the sub scanning operation is achieved by the relative movement of the linear image sensor and the image formed by the imaging optical system with plural scanning speed and the image information is outputted by communication between the image process means for processing the image obtained by each main scanning operation and the external equipment, the apparatus is featured by fetching plural shading data while a scanning motor in the sub scanning direction is driven with such plural scanning speeds.

In an image read apparatus which reads an image from a recording medium, such as a film, and outputs image data, and shading correction data is set. Time elapsed since the shading correction data is set is counted. Before performing main scanning, whether or not the elapsed time is longer than a predetermined period is determined, and if it is, the shading correction data is updated. The read image data is processed with shading correction using the shading correction data which is updated as time elapses.

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Saitama, Japan

Kazuyuki Kondo