Provided is an image sensor lighting unit including at least one light guide extending in a main scanning direction; a first light source group facing a first end surface of at least two end surfaces of the at least one light guide in the main scanning direction; and a second light source group facing a second end surface of the at least two end surfaces. The first light source group includes a first light source that emits light having a predetermined wavelength band. The second light source group includes a second light source that emits light having the wavelength band. An X-coordinate of the first light source in a corresponding XY-coordinate system is equal in absolute value to an X-coordinate of the second light source in a corresponding XY-coordinate system, with the at least one light guide viewed from the first end surface side in the main scanning direction.

A reading device includes a visible light source to irradiate a subject with light having a visible wavelength; an invisible light source to irradiate the subject with light having an invisible wavelength; first and second image sensors to receive reflected light from the subject being irradiated with the light having the visible wavelength and the light having the invisible wavelength, and circuitry. The first image sensor generates visible image data containing a first invisible component, and the second image sensor generates invisible image data of a second invisible component. The circuitry removes the first invisible component contained in the visible image data using the invisible image data. The circuitry multiplies the invisible image data with the correction coefficient that absorbs an individual variation in removal of the first invisible component, and the correction coefficient is generated based on the visible image data and the invisible image.

A plurality of groups are arranged in a light emitting device. Each of the groups includes a plurality of light-emitting elements, a plurality of transistors arranged corresponding to the plurality of light-emitting elements and configured to supply current to the plurality of light-emitting elements, and a group control transistor configured to control current flowing through the plurality of transistors. The plurality of groups have a first group and a second group. The first group has a plurality of light-emitting elements. The second group has a plurality of light-emitting elements. A light-emitting element of the second group is arranged between one light-emitting element of the first group and the other light-emitting element of the first group.

A measurement apparatus includes a light irradiator that irradiates a measurement target with light and a processor that controls the light irradiator, in which the processor is configured to irradiate a specific place of the measurement target with the light from plural places having different positions in one direction, and irradiate the specific place of the measurement target with the light from the plural places having different positions in a direction intersecting the one direction.

An image scanning system for scanning an object is disclosed. The image scanning system includes a light source, an optical lens, an image capturing unit and a light barrier element. The light source irradiates an object to produce an image light, and the optical lens converges the image light. The image capturing unit is disposed at a light leaving side of the optical lens, and the image capturing unit captures the image light to form an image. The light barrier element is disposed at a light entering side of the optical lens or disposed between the optical lens and the image capturing unit, and the light barrier element selectively allows the image light within a predetermined range of an incident angle to pass through.

An image sensor module includes an elongated light emitting unit, a photodetector, a lens unit, a substrate with the photodetector mounted on. The substrate is spaced apart from the lens unit in a thickness direction of the substrate. The image sensor module further includes a resin case provided with a light emitting unit chamber, a lens unit chamber and a substrate chamber. The lens unit chamber has a first bottom face extending in the first direction, and the substrate chamber has a second bottom face extending in the first direction and facing opposite to the first bottom face in the thickness direction of the substrate. The first or second bottom face is formed with at least one protrusion extending in the thickness direction of the substrate.

A reading device includes a visible light source to irradiate a subject with light having a visible wavelength; an invisible light source to irradiate the subject with light having an invisible wavelength; first and second image sensors to receive reflected light from the subject being irradiated with the light having the visible wavelength and the light having the invisible wavelength, and circuitry. The first image sensor generates visible image data containing a first invisible component, and the second image sensor generates invisible image data of a second invisible component. The circuitry removes the first invisible component contained in the visible image data using the invisible image data. The circuitry multiplies the invisible image data with the correction coefficient that absorbs an individual variation in removal of the first invisible component, and the correction coefficient is generated based on the visible image data and the invisible image.

Provided is an image sensor lighting unit including at least one light guide extending in a main scanning direction; a first light source group facing a first end surface of at least two end surfaces of the at least one light guide in the main scanning direction; and a second light source group facing a second end surface of the at least two end surfaces. The first light source group includes a first light source that emits light having a predetermined wavelength band. The second light source group includes a second light source that emits light having the wavelength band. An X-coordinate of the first light source in a corresponding XY-coordinate system is equal in absolute value to an X-coordinate of the second light source in a corresponding XY-coordinate system, with the at least one light guide viewed from the first end surface side in the main scanning direction.

A plurality of groups are arranged in a light emitting device. Each of the groups includes a plurality of light-emitting elements, a plurality of transistors arranged corresponding to the plurality of light-emitting elements and configured to supply current to the plurality of light-emitting elements, and a group control transistor configured to control current flowing through the plurality of transistors. The plurality of groups have a first group and a second group. The first group has a plurality of light-emitting elements. The second group has a plurality of light-emitting elements. A light-emitting element of the second group is arranged between one light-emitting element of the first group and the other light-emitting element of the first group.

A measurement apparatus includes a light irradiator that irradiates a measurement target with light and a processor that controls the light irradiator, in which the processor is configured to irradiate a specific place of the measurement target with the light from plural places having different positions in one direction, and irradiate the specific place of the measurement target with the light from the plural places having different positions in a direction intersecting the one direction.