Abstract: This illumination optical system comprises a laser light source 301, 401, 501, a light collection optical system 311, 411, 511, and a support structure 312, 412 that is able to secure the laser light source and the light collection optical system, wherein the light from the laser light source is focused onto an object to be inspected 307, 407, 507. The light collection optical system comprises a cylindrical mirror 306, 406, 506, and at least one cylindrical lens 304, 404a, 404b, 404c, 504a, 504b, 504c. The cylindrical mirror is an optical element that collects light in a first direction, and the cylindrical lens is an optical element that collects light in a second direction perpendicular to the first direction. The focal distance of the cylindrical lens to the object to be inspected is greater than the focal distance of the cylindrical mirror to the object to be inspected.

Abstract: An evaluation device includes a projector to project a pattern having an edge component onto an object, an imaging device to capture an image of the object, a reflective-property correction unit to correct an amount of change in shape of a virtual image of the pattern reflected in the object, using reflective-property data of a surface of the object, and an evaluation-value calculator to evaluate image clarity of the surface of the object based on the corrected amount of change. A computer-readable non-transitory recording medium storing a program for causing a computer to execute a method. The method includes correcting an amount of change in shape of a virtual image of the pattern reflected in the object based on image data that is obtained by capturing an object onto which a pattern having an edge component is projected, using reflective-property data of a surface of the object.

Abstract: A texture evaluation apparatus includes a projector, an imager, and an evaluator. The projector is configured to project a two-dimensional pattern having an edge element onto an object. The imager is configured to capture an image of a surface of the object. The evaluator is configured to calculate an amount of shape change of a virtual image of the two-dimensional pattern in the image, and evaluate texture of the object based on the amount of shape change and sensory evaluation information obtained in advance.

Abstract: A color measurement apparatus includes at least one illuminator, an imager, and circuitry. The circuitry is configured to normalize each pixel included in an imaging region of one of the spectral reflectance images of the measurement target irradiated with light at a specific illumination angle of the plurality of illumination angles, with one of the spectral reflectance images of the reference object irradiated with light at the specific illumination angle, for each of the plurality of illumination angles so as to generate normalized spectral reflectance images of the measurement target. The circuitry further calculates a numerical value of at least one color for each pixel of the normalized spectral reflectance images of the measurement target, for respective ones of the plurality of illumination angles, to measure color of the surface of the measurement target.

Abstract: An evaluation device includes a projector to project a pattern having an edge component onto an object, an imaging device to capture an image of the object, a reflective-property correction unit to correct an amount of change in shape of a virtual image of the pattern reflected in the object, using reflective-property data of a surface of the object, and an evaluation-value calculator to evaluate image clarity of the surface of the object based on the corrected amount of change. A computer-readable non-transitory recording medium storing a program for causing a computer to execute a method. The method includes correcting an amount of change in shape of a virtual image of the pattern reflected in the object based on image data that is obtained by capturing an object onto which a pattern having an edge component is projected, using reflective-property data of a surface of the object.

Abstract: A color measurement apparatus includes at least one illuminator, an imager, and circuitry. The circuitry is configured to normalize each pixel included in an imaging region of one of the spectral reflectance images of the measurement target irradiated with light at a specific illumination angle of the plurality of illumination angles, with one of the spectral reflectance images of the reference object irradiated with light at the specific illumination angle, for each of the plurality of illumination angles so as to generate normalized spectral reflectance images of the measurement target. The circuitry further calculates a numerical value of at least one color for each pixel of the normalized spectral reflectance images of the measurement target, for respective ones of the plurality of illumination angles, to measure color of the surface of the measurement target.

Abstract: A light irradiation device includes a light source, a light guide member, and a holding member. The light guide member includes an incident surface, an exit surface, and a held surface. The incident surface has an elongated shape in a main scanning direction and faces a light emitting surface of the light source. The light guide member includes a securing structure in each of both end portions in the main scanning direction, which are out of a light guide area of the light guide member. The securing structure in one end portion is an engagement lug structure protruding to penetrate into a through-hole of the holding member, including a lug on a leading end, and engaging the holding member. The securing structure on another end portion is a fastening structure having a fastening hole penetrated with a fastening member and being secured to the holding member with the fastening member.

Abstract: A texture evaluation apparatus includes a projector, an imager, and an evaluator. The projector is configured to project a two-dimensional pattern having an edge element onto an object. The imager is configured to capture an image of a surface of the object. The evaluator is configured to calculate an amount of shape change of a virtual image of the two-dimensional pattern in the image, and evaluate texture of the object based on the amount of shape change and sensory evaluation information obtained in advance.

Abstract: A light irradiation device includes a light source, a light guide member, and a holding member. The light guide member includes an incident surface, an exit surface, and a held surface. The incident surface has an elongated shape in a main scanning direction and faces a light emitting surface of the light source. The light guide member includes a securing structure in each of both end portions in the main scanning direction, which are out of a light guide area of the light guide member. The securing structure in one end portion is an engagement lug structure protruding to penetrate into a through-hole of the holding member, including a lug on a leading end, and engaging the holding member. The securing structure on another end portion is a fastening structure having a fastening hole penetrated with a fastening member and being secured to the holding member with the fastening member.

Abstract: A light irradiator includes a light source and a light guide to guide a light flux from the light source to an illumination area. The light guide has an incident surface, an emission surface and two side surfaces. The emission surface is located apart from a reading optical axis with an inclination relative to the reading optical axis. The following relations are satisfied: S1(x)?S2(x) S1(L)>S2(L) wherein S1 represents a divided cross-sectional area near the reading optical axis and S2 represents a divided cross-sectional area far from the reading optical axis when a virtual cross-sectional area S parallel to the incident surface of the light guide is divided by a plane passing the center of the incident surface, formed by a direction perpendicular thereto and the incident surface and the main scanning direction; S (x) represents a virtual cross-sectional area distant from the incident surface of the light guide by x; L is a distance from the incident surface to the emission surface; and 0?x<L.

Abstract: A light irradiation system for irradiating light to an irradiation area extending in a main scanning direction of a document face when placed on an image scanning apparatus includes a light source; a light guiding member to guide light emitted from the light source; and a reflector to reflect a part of light exiting from the light guiding member to the document face. The irradiation area is irradiated by the reflection light reflected by the reflector and a direct light exiting from the light guiding member without reflection at the reflector. The light guiding member includes an incidence surface where the light from the light source enters; and an exit surface where the light entered from the incidence surface exits. The reflector is disposed at a position in a direction that light intensity of light emitting from the light source becomes the strongest.

Abstract: A light irradiator includes a light source and a light guide to guide a light flux from the light source to an illumination area. The light guide has an incident surface, an emission surface and two side surfaces. The emission surface is located apart from a reading optical axis with an inclination relative to the reading optical axis. The following relations are satisfied: S1(x)?S2(x) S1(L)>S2(L) wherein S1 represents a divided cross-sectional area near the reading optical axis and S2 represents a divided cross-sectional area far from the reading optical axis when a virtual cross-sectional area S parallel to the incident surface of the light guide is divided by a plane passing the center of the incident surface, formed by a direction perpendicular thereto and the incident surface and the main scanning direction; S (x) represents a virtual cross-sectional area distant from the incident surface of the light guide by x; L is a distance from the incident surface to the emission surface; and 0?x<L.

Abstract: A light irradiation device includes: a light source to output diffused light; and a light guide member to guide the diffused light to an irradiation point. The light guide member includes an incidence surface which the diffused light enters, a first emission surface to emit the entered diffused light, while further diffusing the entered diffused light with a first diffusion characteristic to emit the diffused light at a first diffusion angle, and a second emission surface to emit the entered diffused light, while further diffusing the entered diffused light with a second diffusion characteristics to emit the diffused light at a second diffusion angle. The second diffusion angle provided by the second diffusion characteristic is smaller than the first diffusion angle provided by the first diffusion characteristic.

Abstract: An light irradiation system for irradiating light a document face includes a light source; a light guiding member to guide light emitted from the light source; and a reflector to reflect a part of light exiting from the light guiding member to the document face. A direction that emission light intensity of the light emitted from the light source becomes the strongest is different from a direction extending from the light source to an irradiation area. The irradiation area is irradiated by a reflection light reflected by the reflector, and a direct light exiting from the light guiding member without reflection at the reflector. The light guiding member including an incidence surface, an exit surface, and a light guiding part including a total reflection face. Light quantity irradiated to the document face by reflection light is smaller than light quantity irradiated to the document face by direct light.

Abstract: A light irradiation device includes: a light source to output diffused light; and a light guide member to guide the diffused light to an irradiation point. The light guide member includes an incidence surface which the diffused light enters, a first emission surface to emit the entered diffused light, while further diffusing the entered diffused light with a first diffusion characteristic to emit the diffused light at a first diffusion angle, and a second emission surface to emit the entered diffused light, while further diffusing the entered diffused light with a second diffusion characteristics to emit the diffused light at a second diffusion angle. The second diffusion angle provided by the second diffusion characteristic is smaller than the first diffusion angle provided by the first diffusion characteristic.

Abstract: An illumination system includes a light source unit including light emitting elements arranged in array in a main scan direction to project light beams radially, and an optical guide of a long length made from a translucent material to guide incident beams from an exit surface of the light source unit in a certain direction for output, and including at least one surface with a diffuse structure to diffuse a transmitted beam or a reflected beam among the incident beams, wherein the diffuse structure is configured to diffuse the beam at a center at a larger divergence angle than at ends in the main scan direction.

Abstract: An optical radiation device includes a long light source unit in which light emitting elements are arranged in array, a long substrate on which the light source unit is mounted, a long optical guide to guide the light beams from the light emitting elements to a predetermined plane, and an optical collector to collect the light beams reflected by the predetermined plane. The length of an effective read area from a reading center of the optical collector to one end of the predetermined plane is different from that of an effective read area from the reading center to the other end thereof. The optical guide formed by injection molding includes a gate at one end in a length direction and a surface at the other end to exert total reflection, and is disposed so that the gate is positioned on the a same side as a shorter effective read area.

Abstract: A light irradiation system for irradiating light to an irradiation area extending in a main scanning direction of a document face when placed on an image scanning apparatus includes a light source; a light guiding member to guide light emitted from the light source; and a reflector to reflect a part of light exiting from the light guiding member to the document face. The irradiation area is irradiated by the reflection light reflected by the reflector and a direct light exiting from the light guiding member without reflection at the reflector. The light guiding member includes an incidence surface where the light from the light source enters; and an exit surface where the light entered from the incidence surface exits. The reflector is disposed at a position in a direction that light intensity of light emitting from the light source becomes the strongest.

Abstract: An light irradiation system for irradiating light a document face includes a light source; a light guiding member to guide light emitted from the light source; and a reflector to reflect a part of light exiting from the light guiding member to the document face. A direction that emission light intensity of the light emitted from the light source becomes the strongest is different from a direction extending from the light source to an irradiation area. The irradiation area is irradiated by a reflection light reflected by the reflector, and a direct light exiting from the light guiding member without reflection at the reflector. The light guiding member including an incidence surface, an exit surface, and a light guiding part including a total reflection face. Light quantity irradiated to the document face by reflection light is smaller than light quantity irradiated to the document face by direct light.

Abstract: A light irradiator including multiple point light sources arranged in a straight line, a light-transmissive light guiding member provided in front of the point light sources in an emission direction of beams of light emitted from the point light sources, the light guiding member guiding the beams of light in a predetermined direction toward a surface to be irradiated; and two or more protrusions protruding toward the point light sources, provided on a light entering surface of the light guiding member and arranged in the same direction as the point light sources. The light guiding member and the point light sources are positioned such that a distance between the protrusions provided to the light guiding member and irradiation surfaces of the point light sources is equal at two positions.