Abstract:
An image reading apparatus with an image reading lens configured to reduce a field curvature and a magnification error in the sub-scan direction, includes a photoelectric conversion element having picture elements arrayed in the main-scan direction, and an image reading lens for imaging imagewise information on a surface of an original, upon a light receiving surface of the photoelectric conversion element, the image reading lens including at least one anamorphic lens having anamorphic surfaces formed at a light entrance surface and a light exist surface thereof, respectively, wherein, when a sectional shape of the anamorphic surface in a main-scan section which contains an optical axis of the image reading lens and the main-scan direction, is taken as a meridional, a curvature of a sagittal of the anamorphic surface defined within a plane being perpendicular to the main-scan section and containing a normal to the anamorphic surface at an arbitrary position in the meridional direction, changes continuously along the meridional direction from the optical axis.
Abstract:
An image processing apparatus for processing visible image information and invisible image information obtained from visible light and invisible light directed onto an original and from the original onto an image pick-up element via a focusing optical system. The image processing apparatus includes an infrared light source, a visible light source, a focus correction unit that corrects the focus of the images when the images are formed on the image pick-up element and acquired, and a signal processor that corrects a partial magnification difference between the visible image and the infrared image.
Abstract:
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.
Abstract:
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.
Abstract:
An image reading apparatus includes a visible light source; an infrared light source; at least three one-dimensional photoelectric conversion elements extending in a main scanning direction and having respective different spectral sensitivity characteristics; an imaging optical system configured to form an image of image information of an original placed on an original holder and irradiated by the visible light source and the infrared light source on the one-dimensional photoelectric conversion elements; a driving unit configured to change relative optical positions of the imaging optical system and the original in a sub-scanning direction; and a control unit configured to obtain visible-light image information and infrared-light image information of the original by controlling turning-on operations of the visible light source and the infrared light source at every reading in the main scanning direction and by performing relative movement of the image optical system and the original in the sub-scanning direction.
Abstract:
Disclosed is a method of adjusting an image reading apparatus which reads image information of an original by moving relative to the original a carriage retaining a light source, a slit portion, a plurality of mirrors, an imaging device including an optical element with an optical surface rotationally asymmetrical with respect to the optical axis, and a reading device, the method including placing an adjustment chart allowing resolving power evaluation in the sub scanning direction on an original table glass, illuminating the adjustment chart by the light source, and adjusting, by using an image of the adjustment chart thus illuminated, the relative positional relationship in the sub scanning direction among the slit portion, the imaging device, and the reading device by a positioning adjustment device such that imaging of the light beam passing through a slit center of the slit portion is effected on the surface of the reading device. By performing information through adjustment using the adjustment chart, there are provided an adjusting method of image reading apparatus and an image reading apparatus which provide high quality image.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.