There is provided with an illumination apparatus. The illumination apparatus includes a light source. A rod-shaped light guide includes, as a first surface, a light emitting surface that emits light taken from the light source. A light guide cover is configured to cover a second surface different from the first surface among surfaces of the light guide. The second surface is a surface extending in a longitudinal direction of the light guide. The light guide cover is extended in the longitudinal direction. The light guide cover includes at least one finger holding the light guide.

A scanner is disclosed. The scanner includes a light source to emit light of a first color during a first turn-on period and emit light of a second color during a second turn-on period; a sensor to receive light from a scanning area, in response to the light of the first color directed to the scanning area, during a first sensing period, and receive light from the scanning area, in response to the light of the second color directed to the scanning area, during a second sensing period; and a controller to control the timing of the first turn-on period within the first sensing period and the second turn-on period within the second sensing period.

An image reading apparatus is capable of reducing glare that a user feels while PWM-controlling an LED and of detecting an original size in a principal scanning direction with sufficient accuracy. A line sensor receives light emitted from a light source and reflected by an original. When a pressure plate that presses an original to a platen is closed, a control unit controls to supply a line periodic signal of which a period is longer than that for reading an original image to the line sensor, and to supply a lighting control signal of which a duty ratio is smaller than that for reading the original image to the light source in synchronization with the line periodic signal to light the light source and to read an image, and controls to detect length of the original in the principal scanning direction using the image signals from the line sensor.

An illuminating device capable of stably illuminating an irradiated object such as a document while suppressing light loss with a simply structure is provided. An LED array and a reflective plate are disposed sandwiching a slit (St) through which light reflected by a document MS passes and a light-guiding member is disposed on the side of the LED array. The light-guiding member includes a direct emission unit disposed between an illumination range y centered on a document reading position and the LED array and an indirect emission unit disposed between the reflective plate and the LED array, a light incidence face of the direct emission unit and a light incidence face of the indirect emission unit are disposed at mutually different position around the LED array, and the LED array is disposed on a side of an interior angle formed by the light incidence faces.

An optical PH includes: a plurality of current-driven light emitting elements that are arranged in a line-shaped region; a controller that outputs a control voltage instructing an amount of a drive current to be supplied to each of the light emitting elements; and a plurality of drivers that correspond one-to-one with the light emitting elements, and each supply the drive current to a corresponding one of the light emitting elements, wherein the drivers each operate as one of: a high-voltage referring driver that supplies the drive current according to a voltage difference between the control voltage and a reference voltage higher than the control voltage; and a low-voltage referring driver that supplies the drive current according to a voltage difference between the control voltage and a reference voltage lower than the control voltage.

An image scanner includes a controller configured to perform black data acquiring process for each color that includes, in a particular period of time, while controlling a light source to be turned off, controlling each of a plurality of light receiving elements to read an image of an object and transmit read data of the object to a shift register, and in a specific period of time next to the particular period of time, controlling the light source to emit light of a color different from the particular color, and controlling the shift register to output a plurality of pieces of image data of the object as a plurality of pieces of black data for the particular color, the plurality of pieces of image data corresponding to the plurality of pieces of read data of the object transmitted by the plurality of light receiving elements, respectively.

In an image reading device, a controller is configured to perform: calculating a ratio between first and second reference data as evaluation data; designating a target light receiving element from a plurality of light receiving elements one by one sequentially; calculating average evaluation data of the target light receiving element by averaging the evaluation data of a second number of light receiving elements located at positions apart every predetermined distance equal to a length of a first number of consecutively arranged light receiving elements; setting an evaluation range of the target light receiving element by adding/subtracting a predetermined value to/from the average evaluation data; determining whether the evaluation data falls within the evaluation range; in response to determining that the evaluation data is out of the evaluation range, revising the second reference data of the target light receiving element; and generating correction data using the second reference data after revision.

An exposure device includes a first light emitting element substrate including a plurality of first light emitting elements arranged at an arrangement interval T in a longitudinal direction, and a second light emitting element substrate including a part in the longitudinal direction that overlaps with a part of the first light receiving element substrate so as to form an overlapping region. The first and second light emitting element substrates are shifted from each other in a direction perpendicular to the longitudinal direction. The second light emitting element substrate includes a plurality of second light emitting elements arranged in the longitudinal direction. The second light emitting elements are arranged at the arrangement interval T at least outside the overlapping region. When an interval between two of the second light emitting elements of the second light emitting element substrate disposed in the overlapping region is expressed as a specified interval TS, the specified interval TS and the arrangement interval T satisfy:
TTS2T.

An optical print head for illuminating an image carrier facing the optical print head includes: a substrate on which a light emitting element array is mounted; a lens array for focusing light emitted from the light emitting element array onto the image carrier; a holder holding the substrate and the lens array; and at least one spacer member, disposed on the holder, for maintaining a predetermined distance between the lens array and the image carrier, the at least one spacer member being made of curable resin that is cured under a predetermined condition or fixed to the holder with curable adhesive that is cured under a predetermined condition.

An illuminating device capable of stably illuminating an irradiated object such as a document while suppressing light loss with a simply structure is provided. An LED array and a reflective plate are disposed sandwiching a slit (St) through which light reflected by a document MS passes and a light-guiding member is disposed on the side of the LED array. The light-guiding member includes a direct emission unit disposed between an illumination range y centered on a document reading position and the LED array and an indirect emission unit disposed between the reflective plate and the LED array, a light incidence face of the direct emission unit and a light incidence face of the indirect emission unit are disposed at mutually different position around the LED array, and the LED array is disposed on a side of an interior angle formed by the light incidence faces.