Canon Kabushiki Kaisha

Masami Tabata

Tatsundo Kawai

Nobuyoshi Tanaka

Kenji Nagata

Takahiro Kaihotsu

Satoshi Itabashi

Makoto Ogura

Oji Saito

There is disclosed an image reading apparatus constructed by an illuminating unit for illuminating an object in a line shape, an image forming optical system for forming a light, as an image, from the object illuminated by the illuminating unit, a line sensor for converting the light formed as an image by the image forming optical system into an image signal, and a frame for holding the illuminating unit and the line sensor, wherein a shape in which vertices of at least a part of the cross section of the illuminating unit are connected by straight lines is set to a polygon of a pentagon or more, so that an image can be stably read at a high quality.

Illuminating unit having diffusion means

There is disclosed a light guide for guiding light from a light source in a longitudinal direction and radiating the light to illuminate an object to be illuminated, which includes a diffuser for diffusing the light from the light source along the longitudinal direction of the light guide, and a radiator for radiating the light diffused by the diffuser in a predetermined direction. By arranging the diffuser and the radiator so that a normal line passing through the center of the width of the diffuser is different from the predetermined direction at least in the vicinity of the light source when viewed in the longitudinal direction of the light guide, the illuminance distribution of the longitudinal direction of the light guide is uniformed.

Illumination apparatus using light guide

In an image sensor which has a photoelectric conversion element group, an illumination device having light sources of at least three emission colors R, G, and B, an imaging lens, and the like, moire noise in a color output image is eliminated, the original reading time is shortened, and a cost reduction is attained. For this purpose, a sensor array including a linear array of a plurality of photoelectric conversion elements, a lens array for imaging an original image on the sensor array, an illumination device using LEDs having emission colors R, G, and B, and a cover glass are supported by and fixed to a frame. The conjugate length of the lens array is set to fall within the range between the R and G emission wavelengths. An original pressed against the cover glass is illuminated by the illumination device, and light reflected by the original is converted into electrical signals by the sensor array, thereby reading the original image.

Image reading apparatus and image reading system

Image reading apparatus having diffusion means

An image sensor comprises signal generation unit for generating an image signal on the basis of reflected light using a plurality of photoelectric converters arranged on a substrate, and image forming unit for projecting the reflected light, from an original image, within a predetermined area on the substrate on which the signal generation unit is provided, wherein the signal generation unit includes signal output unit for outputting the image signal from the plurality of photoelectric converters to the outside of the signal generation unit, and a part or all of the signal output unit is arranged outside of the predetermined area on the substrate. Accordingly, reflection of light by the electrodes is prevented, and no light noise incidents on the photoelectric converters. Therefore, it is possible to increase the S/N ratio of the image sensor.

Image sensor, and image processing apparatus using the same

A light source or LED element is positioned adjacent to an entrance surface of a light guide element of stick shape made of a light transmissive substrate. The light that has entered from the entrance surface to the interior of the light guide element is scattered by a diffusion area to emerge from an exit surface in a predetermined direction, wherein the light that has entered from the entrance surface into the light guide element is not made incident directly on at least a part of the diffusion area.

Illumination device and information processing apparatus

The form of a light condensing part of an illuminating device is of a freer form such as expressed by a general polynomial, rather than a round cross-sectional form. Accordingly, an illumination device or an image reading apparatus having the same which includes a light guide element having an entrance surface provided at one end thereof for an incident light flux, an exit surface provided on a side other than the one end extending in a longitudinal direction of the light guide element for allowing the incident light flux to exit therefrom, a reflecting and/or scattering area provided at a side other than the exit surface for reflecting and/or scattering the light flux propagated in a light-transmissive member, and a light condensing part provided on the exit surface for condensing the exiting light flux, and a light source provided adjacent to the entrance surface of the light guide element, wherein, assuming that in a cross-section orthogonally intersecting the longitudinal direction, a direction opposite to a normal line of the reflecting and/or scattering area is a z axis and a direction orthogonally intersecting the z axis is a y axis, at least a part of a surface of the light condensing part is expressed by a polynomial of y, and at least one of coefficients of odd-number-th degree terms in the polynomial is not &ldquo;0&rdquo;.

Illumination device and image reading apparatus using the same

An image reading apparatus includes a sensor IC having a group of photoelectric conversion devices which are linearly aligned, a sensor board on which the sensor IC is mounted, a lens for forming light information into an image on the sensor IC, a light source having electrical connection lines, an illumination unit consisting of a light guide for guiding light from the light source and outputting the light in a desired direction, and a frame for holding the respective members. The electrical connection lines of the light source are directly connected to the sensor board. Connector cables for the light source can be omitted, and the image sensor and the external system can be electrically connected through one connector. By simplifying the electrical connection, the influence of noise can be minimized.

Image reading apparatus having light source electrically and directly connected to image sensor board

There is disclosed a light guide for guiding light from a light source in a longitudinal direction and radiating the light to illuminate an object to be illuminated, which comprises a diffuser for diffusing the light from the light source along the longitudinal direction of the light guide, and a radiator for radiating the light diffused by the diffuser in a predetermined direction. By arranging the diffuser and the radiator so that a normal line passing through the center of the width of the diffuser is different from the predetermined direction at least in the vicinity of the light source when viewed in the longitudinal direction of the light guide, the illuminance distribution of the longitudinal direction of the light guide is uniformed.

An image reading apparatus having a light guide unit with a light source for applying light to an image reading surface, and a board provided with a photoelectrical conversion element for photoelectrically converting light reflected from the image reading surface into an electrical signal, wherein the light guide unit is supported by the board by making the light guide unit in contact with the board.

Image reading apparatus

A rod lens array, used in an image sensor, is configured by sandwiching a plurality of rod lenses with two side plates. Among the two side plates, the one which is on the side of the illumination device is made thinner than the other side plate.

Rod lens array and image read apparatus and system using the same

A B line sensor is arranged at the center on a sensor array within the image formation range of a lens array, where the light amount is maximum. R and G line sensors are arranged on both sides of the B line sensor. With this arrangement, an image reading apparatus capable of suppressing variations in output levels depending on the colors of sensors and reading a high-quality image is provided.

Image reading apparatus having line sensors arranged in specific order and with different or same interval between adjacent line sensors

In an image reading device in which an original is illuminated by a light source, and a reflected beam from the original is imaged on a sensor through a rod lens array, a light-shielding member is arranged between the beam exit surface of the light source and the incident surface of the rod lens array to prevent the beam from the light source from being directly incident on the rod lens array to cause a flare. An image reading device and information processing apparatus in which the image quality is rarely degraded by the flare beam are provided.

Growing community of inventors

Isehara, Japan

Masami Tabata