An image reading apparatus includes an LED light source, a CCD sensor receiving light reflected from a document irradiated with light from the LED light source, a fan, and a frame housing the LED light source, the CCD sensor and the fan. The fan circulates air in a substantially sealed space formed by the frame. Thus, temperature difference in the image reading apparatus can be reduced while not degrading dust-proof property of the apparatus, and efficient heat radiation to the outside becomes possible. Thus, variation of sensitivity of CCD sensor, deviation of point of focus of image forming system and deviation of reading position caused by temperature increase can be prevented.

A reading apparatus that reads a sheet includes: a first light emitting diode (LED) configured to emit light with a specific wavelength; a light emitting element including a second LED configured to emit light with the specific wavelength and a phosphor configured to be excited by the light emitted from the second LED; a line sensor configured to generate a reference signal according to a quantity of received light emitted from the first LED and reflected off the sheet, and also generate an image signal according to a quantity of received light emitted from the light emitting element and reflected off the sheet; and a controller configured to generate an image representing the sheet from a differential result obtained by removing a component corresponding to the reference signal from the image signal.

An image reading apparatus includes: three or more light sources configured to each emit light; a light receiving unit including a common light receiving surface configured to detect each light emitted; and an image generation unit configured to cause the three or more light sources to be switched over in a predetermined order and emit the corresponding light, and generate an image read from a document, wherein at least one of the three or more light sources includes a white light source and an optical filter, and the optical filter is configured such that a half-value width of a wavelength with respect to a maximum intensity of a spectral characteristic of the emitted light after transmission is wider than a half-value width of a wavelength with respect to a maximum intensity of the spectral characteristic of the light emitted from at least one of the other light sources.

A lens unit includes a first lens array including first lenses arranged in at least two lines; a second lens array including second lenses arranged in an arrangement relationship corresponding to the first lens array, the second lenses respectively facing the first lenses, the second lens array being arranged to face the first lens array so that each pair of the first and second lenses has a common optical axis; and a first light blocking member arranged between the first lens array and the second lens array and having first openings each being arranged to face the pair of the first and second lenses in a direction of the optical axis. An interval PXL from an array center position between two adjacent lines to the optical axis and an interval PXS from the array center position to an opening center of the first opening satisfy PXL<PXS.

According to at least one embodiment, a lens mirror array includes a plurality of optical elements. An optical element of the plurality of optical elements includes an incident surface on which light is incident, an emitting surface configured to emit the light incident through the incident surface, at least one reflecting surface reflecting the light incident through the incident surface toward the emitting surface, and a light shielding portion configured to block the light. The incident surface includes an effective surface configured to pass effective light emitted from the emitting surface and a directional surface configured to direct unnecessary light to the light shielding portion.

A sheet detecting apparatus includes: a light emitting unit that emits light emitted toward a detection position; a light receiving unit that is provided to receive the light reflected by a sheet present at the detection position and that outputs an electric signal which corresponds to a received light amount; and an adjustment processing unit that adjusts, within a specified range, a duty ratio of a drive pulse signal used to drive the light emitting unit, so that a detection value of the electric signal output from the light receiving unit is included in a specified standard range; and a decision processing unit that decides the specified range based on a change range which is among a variable range of the duty ratio of the drive pulse signal and in which the detection value of the electric signal changes in response to a change in the duty ratio.

A document reader system configured to capture an image of a document is described. The document reader system includes a document reader having a transparent scan area, a light source, an optical filter, and an image sensor. The transparent scan area is configured to receive the document on a first side of the transparent scan area. The light source is positioned on a second side of the transparent scan area opposite the first side and is configured to emit light towards the transparent scan area. The optical filter is positioned between the light source and the transparent scan area and has a variable light transmission configured to modify light intensity of the light emitted by the light source. The image sensor positioned on the second side of the transparent scan area and configured to capture the image of the document on the first side of the transparent scan area.

An image scanner including a two-dimensional matrix sensor, a scanning plane defined by the axes, an optical system, an optical axis perpendicular to the scanning plane and coinciding with an axis, a lighting system including at least four light sources that have its own main axis and are positioned so that each light source is adjacent to one side of the scanning plane and illuminates it from a different direction. Each light source is arranged with its own main axis in a plane parallel to a facing mirror-reflecting surface above said facing mirror-reflecting surface and is oriented so as to radiate the scanning plane by specularly reflecting its light beams on the respective mirror-reflecting surface situated on the opposite side of the scanning plane with respect to the light source.

Provided is a banknote sorter. A light source unit obliquely illuminates light at a designated angle onto a surface of a banknote when the banknote is being transferred through the banknote sorter by a driving means. A light sensor unit is placed to sense the light that is irradiated at the designated angle onto the surface of the banknote and/or tape, reflected from the surface of the banknote and/or the tape, and is incident onto the light sensor unit at an angle different from the designated angle. A control unit controls the light source unit, processes sensing information from the light sensor unit, and discriminates any tape on the banknote.

The disclosure includes a fixed retail scanner including a data reader. The data reader includes illumination assemblies that include different LED sub-groups that are co-located within its respective assembly. These illumination assemblies may be identically constructed and installed at various positions within the data reader to provide active illumination for the camera modules. Illumination assemblies are activated together, but only with the first sub-groups from each of the illumination assemblies being activated together at a first time, and only with the second sub-groups from each of the illumination assemblies being activated together at a second time.