Abstract: Provided is the light guiding member including an incident surface, an exit surface extending in a first direction, a light guiding surface opposed to the exit surface, and being configured to guide light entering the incident surface to the exit surface, a side surface connecting the exit surface and the light guiding surface, and a held portion formed on the side surface. The light guiding surface includes a plurality of deflection portions arrayed in the first direction. At least one of a density or a depth of each of the plurality of deflection portions differs between a first region on the light guiding surface, which corresponds to a region at which the held portion is present in the first direction, and a second region on the light guiding surface adjacent to each of both sides of the first region in the first direction.

Abstract: Provided is the light guiding member including an incident surface, an exit surface extending in a first direction, a light guiding surface opposed to the exit surface, and being configured to guide light entering the incident surface to the exit surface, a side surface connecting the exit surface and the light guiding surface, and a held portion formed on the side surface. The light guiding surface includes a plurality of deflection portions arrayed in the first direction. At least one of a density or a depth of each of the plurality of deflection portions differs between a first region on the light guiding surface, which corresponds to a region at which the held portion is present in the first direction, and a second region on the light guiding surface adjacent to each of both sides of the first region in the first direction.

Abstract: A light-guide member includes a light-incident surface formed at an end portion of the light-guide member in a first direction, a light-emitting surface that is elongated in the first direction and that includes first and second light-emitting regions, which cause light to be emitted in different directions in a first cross section that is perpendicular to the first direction, a common deflecting portion that deflects light from the light-incident surface and causes the light to be emitted from the first and second light-emitting regions to the outside, and first and second protruding portions each of which is located on one of two sides of the deflecting portion in the first cross section, the first and second protruding portions protruding in a direction away from the light-emitting surface with respect to the deflecting portion.

Abstract: An image reading apparatus according to the present invention is an image reading apparatus including a reading unit that illuminates an original and reads an image of the original, wherein the apparatus can execute a first mode of reading the image of the moving original while the reading unit is kept stationary, and a second mode of reading the image of the stationary original while moving the reading unit, the apparatus further includes a light condensing unit that refracts a light flux from the reading unit and condenses the light flux on the original in the first mode, and the light flux from the reading unit incidents on the original without passing through the light condensing unit in the second mode.

Abstract: A light-guide member includes a light-incident surface formed at an end portion of the light-guide member in a first direction, a light-emitting surface that is elongated in the first direction and that includes first and second light-emitting regions, which cause light to be emitted in different directions in a first cross section that is perpendicular to the first direction, a common deflecting portion that deflects light from the light-incident surface and causes the light to be emitted from the first and second light-emitting regions to the outside, and first and second protruding portions each of which is located on one of two sides of the deflecting portion in the first cross section, the first and second protruding portions protruding in a direction away from the light-emitting surface with respect to the deflecting portion.

Abstract: Provided is an image reading apparatus capable of reading an image of an original at a high resolution by an image pickup unit by reducing an influence of a dark line included in a projection image on an original placing stand, which is ascribable to a displaying element included in a projecting unit and is to be exerted on an original placed on original placing stand. The image reading apparatus includes: an image pickup unit conducting image pickup for a placing surface; a projecting unit projecting an image on placing surface; and a switching unit switching a blur amount of image on placing surface, in which the switching unit sets a blur amount of image in a first mode, in which the image pickup is not conducted by image pickup unit, smaller than that in a second mode, in which the image pickup is conducted by image pickup unit.

Abstract: An image reading apparatus according to the present invention is an image reading apparatus including a reading unit that illuminates an original and reads an image of the original, wherein the apparatus can execute a first mode of reading the image of the moving original while the reading unit is kept stationary, and a second mode of reading the image of the stationary original while moving the reading unit, the apparatus further includes a light condensing unit that refracts a light flux from the reading unit and condenses the light flux on the original in the first mode, and the light flux from the reading unit incidents on the original without passing through the light condensing unit in the second mode.

Abstract: Provided is an image reading apparatus capable of reading an image of an original at a high resolution by an image pickup unit by reducing an influence of a dark line included in a projection image on an original placing stand, which is ascribable to a displaying element included in a projecting unit and is to be exerted on an original placed on original placing stand. The image reading apparatus includes: an image pickup unit conducting image pickup for a placing surface; a projecting unit projecting an image on placing surface; and a switching unit switching a blur amount of image on placing surface, in which the switching unit sets a blur amount of image in a first mode, in which the image pickup is not conducted by image pickup unit, smaller than that in a second mode, in which the image pickup is conducted by image pickup unit.

Abstract: Provided is a light guiding unit including: a light guiding member including an incident surface, an exit surface elongated in a first direction, and a light guiding surface opposed to exit surface; and a diffusion member opposed to light guiding surface, in which: light entering the light guiding member from incident surface is guided via light guiding surface and diffusion member to exit surface, and exits from exit surface to illuminate the original; the light guiding member further includes a plurality of prisms arrayed in first direction on light guiding surface on a side opposed to diffusion member; each of prisms has a rectangular shape in a first section; and each of prisms satisfies the following condition: W tan(sin?1(1/n))?H?2W, where W and H represent a width and a height of each of prisms in the first section, respectively, and n represents a refractive index of the light guiding member.

Abstract: Provided is a light guiding unit including: a light guiding member including an incident surface, an exit surface elongated in a first direction, and a light guiding surface opposed to exit surface; and a diffusion member opposed to light guiding surface, in which: light entering the light guiding member from incident surface is guided via light guiding surface and diffusion member to exit surface, and exits from exit surface to illuminate the original; the light guiding member further includes a plurality of prisms arrayed in first direction on light guiding surface on a side opposed to diffusion member; each of prisms has a rectangular shape in a first section; and each of prisms satisfies the following condition: W tan(sin?1(1/n))?H?2W, where W and H represent a width and a height of each of prisms in the first section, respectively, and n represents a refractive index of the light guiding member.

Abstract: An illumination device and an image reading apparatus having improved heat resistance and spectral characteristics are provided. An illumination device used in an image reading apparatus that moves relative to a read area of a document includes: a light source; a light guide including an incident surface on which light from the light source is incident and an exit surface from which light from the light source exits; and a spectroscopic unit that is provided between the light source and the light guide and includes, on a surface of a glass substrate facing the light source, a multi-layer film for reflecting infrared light toward the light source.

Abstract: An illumination apparatus includes a light source, a light guide, and a holding member configured to hold the light source and to hold the light guide via a fixing member. Within a cross section including a plane normal direction of an exit surface of the light source and a plane normal direction of an entrance surface of the light guide, the plane normal direction of the entrance surface of the light guide or a direction within a surface of the light guide contacting the fixing member and the plane normal direction of the exit surface of the light source or a maximum intensity direction in light emission of the light source are inclined relative to each other such that a ray of light from the light source in the maximum intensity direction is refracted at the entrance surface of the light guide in a direction away from the fixing member.

Abstract: Provided is a light guide, in which: at least one of a reflecting part or a light exit part has a light condensing action in a direction intersecting a predetermined direction; the at least one of the reflecting part or the light exit part includes diffusing parts arranged in the predetermined direction; the diffusing parts include: a first curved surface having a first degree of diffusion in the predetermined direction for a sparse region of light sources; and a second curved surface having a second degree of diffusion, which is lower than the first degree of diffusion, in the predetermined direction for a dense region of the light sources; and each of the first curved surface and the second curved surface has a shape corresponding to a part of a cylinder extending in a direction orthogonal to the predetermined direction in which the light sources are arrayed.

Abstract: An illumination device and an image reading apparatus having improved heat resistance and spectral characteristics are provided. An illumination device used in an image reading apparatus that moves relative to a read area of a document includes: a light source; a light guide including an incident surface on which light from the light source is incident and an exit surface from which light from the light source exits; and a spectroscopic unit that is provided between the light source and the light guide and includes, on a surface of a glass substrate facing the light source, a multi-layer film for reflecting infrared light toward the light source.

Abstract: Provided is a light guide, in which: at least one of a reflecting part or a light exit part has a light condensing action in a direction intersecting a predetermined direction; the at least one of the reflecting part or the light exit part includes diffusing parts arranged in the predetermined direction; the diffusing parts include: a first curved surface having a first degree of diffusion in the predetermined direction for a sparse region of light sources; and a second curved surface having a second degree of diffusion, which is lower than the first degree of diffusion, in the predetermined direction for a dense region of the light sources; and each of the first curved surface and the second curved surface has a shape corresponding to a part of a cylinder extending in a direction orthogonal to the predetermined direction in which the light sources are arrayed.

Abstract: An image reading optical system, including: an imaging optical system used for imaging a slit area of a document and includes an optical element having different cross section shapes in a main scanning direction and in a sub-scanning direction; an aperture stop; and an optical phase changing filter disposed adjacent to the aperture stop and including a phase lead area and a phase delay area, in which the optical phase changing filter includes a surface shape component that is symmetric only with respect to a predetermined plane including a surface normal at the center of the incident beam and one of the main scanning direction and the sub-scanning direction, and with respect to a surface that includes the surface normal at the center of the incident beam and is perpendicular to the predetermined plane, one side is the phase lead area, and another side is the phase delay area.

Abstract: An illumination apparatus includes a light source, a light guide, and a holding member configured to hold the light source and to hold the light guide via a fixing member. Within a cross section including a plane normal direction of an exit surface of the light source and a plane normal direction of an entrance surface of the light guide, the plane normal direction of the entrance surface of the light guide or a direction within a surface of the light guide contacting the fixing member and the plane normal direction of the exit surface of the light source or a maximum intensity direction in light emission of the light source are inclined relative to each other such that a ray of light from the light source in the maximum intensity direction is refracted at the entrance surface of the light guide in a direction away from the fixing member.

Abstract: Provided is a light guide, in which: at least one of a reflecting part or a light exit part has a light condensing action in a direction intersecting a predetermined direction; the at least one of the reflecting part or the light exit part includes diffusing parts arranged in the predetermined direction; the diffusing parts include: a first curved surface having a first degree of diffusion in the predetermined direction for a sparse region of light sources; and a second curved surface having a second degree of diffusion, which is lower than the first degree of diffusion, in the predetermined direction for a dense region of the light sources; and each of the first curved surface and the second curved surface has a shape corresponding to a part of a cylinder extending in a direction orthogonal to the predetermined direction in which the light sources are arrayed.