Abstract: In one embodiment, an illumination device includes a light-guiding unit having a light output surface which outputs light and a back surface facing the light output surface, wherein the light-guiding unit has a curved surface in a region of the back surface farther than a first position on the back surface that is away by a first distance from an axis passing the light output surface and the back surface, and a rough surface in a region of the light output surface farther than a second position on the light output surface that is away by a second distance from the axis in a same direction as a direction from the axis toward the first position, and where an intersection of the axis and the back surface is an origin point, and a direction of the axis from the back surface to the light output surface is positive, a normal line of the curved surface intersects with the axis at the positive side of the axis, and an angle formed by a normal line vector at the second position in a direction toward the light output s

Abstract: A lighting apparatus according to an embodiment includes a globe, an optical element including a scattering portion inside and transparent to visible light, and a light source disposed to be opposed to a light incident surface of the optical element. The scattering portion is disposed inside the globe.

Abstract: An LED lighting device of embodiment comprising an LED light source which generates an ultraviolet light or a visible light, an axisymmetric transparent member which is provided over the light source and which is transparent to visible light, and an axisymmetric light scattering member disposed in the transparent member apart from the light source. A distance of closest approach L2 between the light source and the light scattering member, and an area C of a light emitting surface of the light source satisfy the settled relation. A length L1 of the light scattering member, and an absorption coefficient ? (1/mm) of the light scattering member satisfy the settled relation. A diameter d1 of the bottom surface of the light scattering member, the distance of closest approach L2, and a refractive index n of the transparent member satisfy the settled relation.

Abstract: A lighting apparatus according to an embodiment includes a globe, an optical element including a scattering portion inside and transparent to visible light, and a light source disposed to be opposed to a light incident surface of the optical element. The scattering portion is disposed inside the globe.

Abstract: An optical element according to an embodiment is formed from a material transparent to visible light and has a rotationally symmetrical shape with respect to the central axis. A cavity containing no transparent material is provided inside the optical element. The inner surface of the cavity has a shape in which a boundary line of the cavity along which a plane including the central axis intersects the inner surface includes a curve portion expanding toward the outside of the optical element. The inner surface of the cavity does not include any surface recessed inwardly.

Abstract: A light guide plate according to an embodiment includes an exit surface where light exits, a rear surface facing this exit surface, and an end face connecting the exit surface and the rear surface. The light guide plate is transparent when no light is entering from the end face. First light scattering means is provided in the rear surface to inwardly reflect the light which has entered from the end face. Second light scattering means is provided in the exit surface to transmit more light than the first light scattering means.

Abstract: A lighting device according to one embodiment includes a light guide member, at least one light source and a substrate on which the light source is mounted. The light guide member includes a first surface facing an outside of the lighting device, a second surface opposite to the first surface, and a side surface extending from an end of the first surface to an end of the second surface. The light guide member also includes a diffusion portion. The light source faces a side surface of the light guide member. The casing includes a thermal dissipation portion formed of a metal and extending along the second surface of the light guide member. The casing supports the substrate and is thermally connected to the light source.

Abstract: An LED lighting device of embodiment comprising an LED light source which generates an ultraviolet light or a visible light, an axisymmetric transparent member which is provided over the light source and which is transparent to visible light, and an axisymmetric light scattering member disposed in the transparent member apart from the light source. A distance of closest approach L2 between the light source and the light scattering member, and an area C of a light emitting surface of the light source satisfy the settled relation. A length L1 of the light scattering member, and an absorption coefficient ? (1/mm) of the light scattering member satisfy the settled relation. A diameter d1 of the bottom surface of the light scattering member, the distance of closest approach L2, and a refractive index n of the transparent member satisfy the settled relation.

Abstract: In one embodiment, an illumination device includes a light-guiding unit having a light output surface which outputs light and a back surface facing the light output surface, wherein the light-guiding unit has a curved surface in a region of the back surface farther than a first position on the back surface that is away by a first distance from an axis passing the light output surface and the back surface, and a rough surface in a region of the light output surface farther than a second position on the light output surface that is away by a second distance from the axis in a same direction as a direction from the axis toward the first position, and where an intersection of the axis and the back surface is an origin point, and a direction of the axis from the back surface to the light output surface is positive, a normal line of the curved surface intersects with the axis at the positive side of the axis, and an angle formed by a normal line vector at the second position in a direction toward the light output s

Abstract: A recording media deciding apparatus has: a light radiating portion which radiates light having a uniform light amount on a range corresponding to an image capturing range of a first surface of a bundle of recording media; a light detecting portion which captures an image of light emitted from a second surface different from the first surface of the bundle of the recording media; and a controller which decides on a type of the recording media based on an output of the light detecting portion.

Abstract: According to one embodiment, a sheet type determination apparatus includes a tray, light source, detection unit, database, and operation unit. The tray is configured to hold a sheet bundle formed by stacked sheets. The light source emits illumination light to a first region. The detection unit detects a light intensity distribution of transmitted light emerging from a second region. The transmitted light is generated as the illumination light passes through the sheet bundle, and the second region is different from the first region. The database stores a table describing a relation between reference attenuation rates and types. The operation unit is configured to calculate an attenuation rate of the transmitted light based on the light intensity distribution, and determine a type of the sheets by comparing the attenuation rate with the reference attenuation rates.

Abstract: A recording media deciding apparatus has: a light radiating portion which radiates light having a uniform light amount on a range corresponding to an image capturing range of a first surface of a bundle of recording media; a light detecting portion which captures an image of light emitted from a second surface different from the first surface of the bundle of the recording media; and a controller which decides on a type of the recording media based on an output of the light detecting portion.

Abstract: A record medium determining device 1, which determines a kind of a record medium 16 by irradiating a laser light 17 to a surface of the record medium 16, detecting a received light position and a received light intensity of a reflected light 18 by a line sensor 14, and comparing a distribution state of the received light position and the received light intensity with a previously determined distribution state, is disposed on the upstream side of a record medium conveyance path 653 with respect to a fixing unit.

Abstract: According to one embodiment, a sheet type determination apparatus includes a tray, light source, detection unit, database, and operation unit. The tray is configured to hold a sheet bundle formed by stacked sheets. The light source emits illumination light to a first region. The detection unit detects a light intensity distribution of transmitted light emerging from a second region. The transmitted light is generated as the illumination light passes through the sheet bundle, and the second region is different from the first region. The database stores a table describing a relation between reference attenuation rates and types. The operation unit is configured to calculate an attenuation rate of the transmitted light based on the light intensity distribution, and determine a type of the sheets by comparing the attenuation rate with the reference attenuation rates.

Abstract: A record medium determining device 1, which determines a kind of a record medium 16 by irradiating a laser light 17 to a surface of the record medium 16, detecting a received light position and a received light intensity of a reflected light 18 by a line sensor 14, and comparing a distribution state of the received light position and the received light intensity with a previously determined distribution state, is disposed on the upstream side of a record medium conveyance path 653 with respect to a fixing unit.

Abstract: A record medium determining device 1, which determines a kind of a record medium 16 by irradiating a laser light 17 to a surface of the record medium 16, detecting a received light position and a received light intensity of a reflected light 18 by a line sensor 14, and comparing a distribution state of the received light position and the received light intensity with a previously determined distribution state, is disposed on the upstream side of a record medium conveyance path 653 with respect to a fixing unit.

Abstract: A record medium determining device 1, which determines a kind of a record medium 16 by irradiating a laser light 17 to a surface of the record medium 16, detecting a received light position and a received light intensity of a reflected light 18 by a line sensor 14, and comparing a distribution state of the received light position and the received light intensity with a previously determined distribution state, is disposed on the upstream side of a record medium conveyance path 653 with respect to a fixing unit.

Abstract: A record medium determining device 1, which determines a kind of a record medium 16 by irradiating a laser light 17 to a surface of the record medium 16, detecting a received light position and a received light intensity of a reflected light 18 by a line sensor 14, and comparing a distribution state of the received light position and the received light intensity with a previously determined distribution state, is disposed on the upstream side of a record medium conveyance path 653 with respect to a fixing unit.

Abstract: In a discriminating apparatus, a substrate portion of printed matter is irradiated with a light beam emitted from a light source, and the intensity of the light beam reflected from the substrate is detected by a photodetector. The discrimination as to whether the printed matter is the original or a reproduction is performed by a discriminating unit based on the contrast value in the intensity of the reflected light detected by the photodetector. Thus, the discriminating apparatus discriminates whether the printed matter is the original or a reproduction at high speed and also permits lowering the possibility of an erroneous discrimination.

Abstract: A sheet thickness measuring device includes: an illumination unit that outputs a light that is illuminated into a stack of sheets from a first area defined on one of faces including a top face, a bottom face, and side faces of the stack of sheets; a detection unit that detects a light amount distribution of light entered into the stack of sheets and propagated to a second area through the stack of sheets, the second area defined on one of the side faces of the stack of sheets; and a calculation unit that calculates a thickness of a sheet in the stack of sheets based on the light amount distribution detected by the detection unit.