Abstract: The image reading apparatus includes a light transmissive member, a first light source causing a first light to enter the light transmissive member from a first side face of side faces thereof, a second light source illuminating a document laid on an upper face of the light transmissive member with a second light, an image sensor photoelectrically converting an optical image, and an imaging optical system forming on image sensor the object image with light exiting from the light transmissive member. The first light source is disposed such that the first light emitted therefrom and entering the light transmissive member from the first side face satisfies a total reflection condition at the upper and lower faces of the light transmissive member.

Abstract: A linear light source module comprises a holder, a first light guide, a second light guide, a first light-emitting element and a second light-emitting element. The first and second light guides are mounted on the holder and arranged in series, where the first light guide has a first emitting surface and the second light guide has a second emitting surface. The holder partially surrounds the first and second light guides. The first light-emitting element is disposed close to a first end of the first light guide, and a light beam emitted by the first light-emitting element is reflected and converted by the first light guide into first linear light emitted from the first emitting surface. The second light-emitting element is disposed close to a first end of the second light guide, and a light beam emitted by the second light-emitting element is reflected and converted by the second light guide into second linear light emitted from the second emitting surface.

Abstract: An image scanning apparatus may include a scanner configured to scan a manuscript and generate a plurality of scan images; a discriminator configured to calculate a color ratio regarding each of the generated plurality of scan images, compare the calculated color ratio and a predetermined reference value, and discriminate color or black and white regarding each of the generated plurality of scan images; and a controller configured to control the discriminator so that a same discrimination is can be performed regarding ‘a scan image having a color ratio within a predetermined range including the predetermined reference value’ of among the plurality of scan images.

Abstract: A method includes reading an image of a document obtained by a reading unit exposing the document to light with an exposure unit, causing the reading unit to perform first reading processing for reading first information obtained by causing the exposure unit to perform exposure with a first light amount, and second reading processing for reading second information obtained by causing the exposure unit to perform exposure with a second light amount that is smaller than the first light amount while no document is placed at a reading position of the reading unit, and detecting a foreign matter existing at the reading position according to a difference between the first and second information.

Abstract: A scanning device includes a first scanning unit having a first line sensor and a first light source that emits a first light beam and is arranged only at one side of the first scanning unit in a main scanning direction, and a second scanning unit having a second line sensor and a second light source that emits a second light beam and is arranged only at one side of the second scanning unit in the main scanning direction. The first scanning unit and the second scanning unit face each other and are disposed such that the first light source and the second light source are arranged at the same side of the main scanning direction, and centers of the first line sensor and the second line sensor are located at the same position in the main scanning direction.

Abstract: According to one embodiment, an imaging device array includes a plurality of imaging devices integrally including an incidence surface that converges light in the primary scanning direction, plural reflective surfaces that reflect light from the incidence surface multiple times, and an exit surface through which light that has reflected at the plural reflective surfaces exits the array. At least one of the plural reflective surfaces is formed at the apex of a protrusion that protrudes outwardly from the surface of the array, and the light that is output from the exit surface is imaged at an image point.

Abstract: An overhead image reading apparatus 1 includes: an image-capturing unit 22 that captures an image of a medium S to be read from above when the medium S to be read is placed on a placement surface 2; a light source 21 that irradiates the medium S to be read with light when the image-capturing unit 22 captures the image of the medium S to be read; and a light blocking portion 25 that blocks light above an upper-end position of light emitted from the light source 21. As a result, the user 100 can be prevented from seeing light from the light source 21 with his/her eyes and from being dazzled with an unpleasant feeling by light from the light source 21 during reading on the medium S to be read.

Abstract: A scanning device includes a first scanning unit having a first scanning element array to scan a first surface of a scan-target medium to acquire a first image, a second scanning unit having a second scanning element array to scan a second surface of the scan-target medium to acquire a second image, and an output unit that outputs a first image signal of the first image and a second image signal of the second image. The first scanning unit and the second scanning unit face each other to scan the first surface and the second surface concurrently. When the scanning directions of the first scanning element array and the second scanning element array are the same, a mirrored image acquired from one of the first image signal and the second image signal is inverted so that the output unit outputs normal images of the first surface and the second surface.

Abstract: An image reading unit includes an image reading section that reads an image of a document in a one-dimensional direction by one-dimensionally aligned imaging elements, a light source that irradiates an image reading region by the image reading section with light, and a rotation head that holds the image reading section and the light source in a manner that the image reading section and the light source are rotatable relative to the document about a rotation axis which is parallel to an alignment direction of the imaging elements.

Abstract: Provided is an image reading apparatus including a light source that irradiates an original document that passes through a reading position with light, a light receiving unit that receives reflected light from the original document, a background member that is inclined at an angle where a difference between an incident angle of the light from the light source and a reflection angle of the light to the light receiving unit is smaller than a difference therebetween on the original document present at the reading position, with the original document at the reading position interposed between the background member and the light source, and a foreign substance detecting section that detects, when the original document is not present at the reading position, a foreign substance present at the reading position.

Abstract: An image reading apparatus includes a light-emitting device having a peak wavelength that varies depending on a value of a drive current, and illuminates a document with illumination light from the light-emitting device. A light receiving unit receives a light reflected from the document when the illumination light is emitted from the light-emitting device, and converts the received reflected light into image data at a predetermined sensitivity depending on the wavelengths of the received light. A current drive circuit supplies the drive current to turn on the light-emitting device. A wavelength distribution control unit produces two or more durations each having a different value of the drive current by controlling the current drive circuit during each main scanning to the document to produce two or more durations each having a different peak wavelength in each main scanning.

Abstract: An image forming apparatus includes an automatic document feeder to feed an original document downstream, a frame, an image reader to read the original document fed by the automatic document feeder, and an image reader mounting unit to hold the image reader thereon. The frame pivotally supports the image reader mounting unit. A parallelism adjusting unit is provided to adjust parallelism of the image reader mounting unit. The parallelism adjusting unit is disposed on a side opposite a pivoting center for the image reader mounting unit at a prescribed interval therefrom. The pivoting center is located near a reading reference point in the image reader, at which the image reader starts reading the original document in main and sub-scanning directions.

Abstract: A multi-functional device comprising an image forming apparatus to form a printing image and a scanner module to scan an image in a main scanning direction. The scanner module includes an illuminator to illuminate a light to a document mount, a sensor unit to read an image information of an object placed on the document mount, and an imaging lens which is disposed between the document mount and the sensor unit and focuses the light reflected from the object onto the sensor unit. The illuminator includes a light source to emit light, a light guiding unit which is lengthened in a sub-scanning direction, faces the document mount and changes a traveling path of the light emitted from the light source to illuminate the document mount, and a guide holder which comprises an installation part where the light guiding unit is installed, and a mounting part where the light source holder is mounted to provide the light source at least one side of the light guiding unit.

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: A linear light source device illuminates a document properly, and an image reading device includes such a light source device. The light source device includes a light source and a light-guiding member. The light-guiding member introduces the light emitted from the light source from one end portion in x-direction, cause the light to travel in x-direction, and emits the light from a light exit portion at one end in z-direction, which is orthogonal to x-direction. The light-guiding member includes, at the other end in z-direction, a light-reflecting portion that reflects light to the light exit portion. One end face of the light-guiding member in y-direction, which is orthogonal to x- and z-directions, is inclined so as to become closer to the other end face in y-direction with decreasing distance from the light exit portion in z-direction. This allows light to easily travel to the light-reflecting portion.

Abstract: A light guide has first and second light guide parts (S, T) in front and rear of a constricted part (2). The first light guide has first and second side parts (1a, 1b). The second light guide part has a reflection condensing part (4) and third and fourth side parts extending from the constricted part to divert the first and second side parts more outward than imaginary surfaces (1c, 1d) as extensions of the first and second side parts beyond the constricted part.

Abstract: A cover member is openable and closable with respect to a document table, and has a color reference surface facing the document table, and a partial region provided on a color reference surface and having a predetermined density different from a density of the color reference surface. When a document determination portion determines that a document is a book document, a density correction portion corrects a density in a specific density correction range at a central portion in document image data read from a document by a image reading portion, based on a second density difference which is a density difference between a density of the color reference surface read by a reading control portion when a book document is placed on a document placement surface, and a density of the color reference surface read by the image reading portion when the cover member is closed.

Abstract: A document reading device includes: a reading position at which information on a document is read; a light source that radiates light toward the document passing through the reading position; a light receiving section that receives reflected light generated from the light from the light source; and a background reflection section disposed to reflect the light from the light source so as to be received by the light receiving section through the reading position. When the document is not present, the background reflection section reflects an amount of light that is greater than an amount of document-reflected light reflected by the document which is white. The background reflection section is formed by processing a specular surface so as to reflect an amount of light that is less than an amount of specularly reflected light reflected by a specular surface.

Abstract: A light source section of the image reading apparatus illuminates a document with light. An image sensor outputs image signals. An operating section accepts input of an enlargement factor and selection of a document scanning mode. An image processing section generates image data, from pixels (lines) in a quantity according to an enlargement factor. A stepper motor moves the document or the light source section. During a quiet mode, a signal generating section inputs to the stepper motor a pulse signal of a fixed frequency within a quiet mode frequency band. The quiet mode frequency band is a frequency band in which vibration of the stepper motor is at or below a predetermined normal vibration level.

Abstract: A plurality of light beams are simultaneously scanned on a surface of a photosensitive member. The surface of the photosensitive member has a curvature factor, and therefore, the light beams have different optical path lengths. Due to differences in the optical path length, a length (scanning width) of a scanning line of one light beam is different from that of another light beam. When a temperature of an optical scanning apparatus increases, the optical path length differences vary, so that differences in magnification between the beams also vary. Therefore, by obtaining correction amounts for the scanning widths depending on the temperature, the light beams are allowed to have substantially the same scanning width even when the temperature of the optical scanning apparatus varies.

Abstract: A document scanner comprises a first image sensor unit (32) and a second image sensor unit (30) and a scanning mechanism (70, 72, 76, 80) for causing relative movement between a document and the units so that the units scan the document in a scanning direction. The first unit (32) is situated ahead of the second unit (30) in the scanning direction and partially overlaps the second unit.

Abstract: A fixing device includes a light irradiation portion that irradiates a recording medium transported to a predefined position with light, a power supply member that is disposed at a position which is irradiated with light with a first intensity of light emitted from the light irradiation portion in a state in which the recording medium is disposed at the predefined position and which is irradiated with light with a second intensity larger than the first intensity of light in a state in which the recording medium is not disposed at the predefined position, and that changes a physical property thereof so as to reduce the supply of power when the power supply member is continuously irradiated with the light with the second intensity for a predefined time or more, and a power supply portion that supplies power to the light irradiation portion via the power supply member.

Abstract: A 3D scanner for recording the 3D topography of an object, the 3D scanner includes an illumination unit configured for providing probe light for illuminating the object, where the probe light includes a pattern of light rays; an image sensor for acquiring one or more 2D images of light rays returning from the illuminated object; an optical system including an optical element arranged such that the patterned probe light passes through it when propagating towards the object from the illumination unit along an optical path; and a device for changing the configuration of the optical system between a first and a second configuration, where the change in configuration comprises a change in orientation of the optical element between a first orientation and a second orientation relative to the optical path of the probe light.

Abstract: An image forming apparatus includes a detection unit that emits light on a recording medium or a platen and detects reflected light while the detection unit moves in a direction perpendicular to a transportation direction of the recording medium; a width calculation unit that compares a value indicative of light intensity responsive to the reflected light with a threshold, and calculates a width of the recording medium measured from a position of the detection unit where the value indicative of light intensity responsive to the reflected light becomes greater than or equal to the threshold; an image formation unit that performs an operation of forming an image based on the calculated width of the recording medium; and an image formation control unit that halts the operation of forming the image upon detecting that the calculated width is less than or equal to a predefined value.

Abstract: A lighting unit includes LED chips positioned in an array form in a main scanning direction on LED substrates. Cylindrical parabolic mirrors each form a shape in which a cylindrical paraboloid having curvature with respect to an sub-scanning direction has been clipped by an axial plane that is perpendicular to the vertex of the cylindrical paraboloid in the main scanning direction, and project light emitted from the light source on an illumination area of an illuminated item. Each cylindrical parabolic mirror includes an anchoring section that is provided at the vertex of the cylindrical paraboloid, and extends from the vertex in an outside direction of the cylindrical paraboloid. Heat-radiating plates each have a contact section that is in contact with the LED substrate, and a non-contact section. Each LED substrate is interposed between the contact section of the heat-radiating plate and the anchoring section of the cylindrical parabolic mirror.

Abstract: An image reading device including an illumination unit that has a light guide body guiding light of a light source that is facing one longitudinal end surface of the light guide body to an object to be read; and an image forming optical device that is parallel to the light guide body, has a lens array with an incidence surface in which lens surfaces are arranged in the longitudinal direction of the light guide body, and condenses reflected light from the object which is incident on the incidence surface, thereby forming an erect equal-magnification image on a sensor. The image reading device further includes a frame on which is disposed the image forming optical device. A second frame projects in a direction away from the first frame and connects to the first frame, or the frame connects to an H-shaped cross-section frame.

Abstract: A document illumination device includes a light-conducting member in which is formed a base surface that extends along a lengthwise direction, an irradiation surface that extends along the lengthwise direction and is tilted in the widthwise direction relative to the base surface, and a side surface that extends in the lengthwise direction and connects the base surface to the irradiation surface; a scattering member that is provided opposing the base surface and the side surface and that scatters light emitted from the base surface and the side surface; and a light source provided opposing a lengthwise direction-end surface of the light-conducting member.

Abstract: An image scanner includes: an image sensor that photo-electrically converts reflected light from a document irradiated with light by a light source; an A/D converter that converts an analog image signal output from the image sensor into a digital signal; a lighting control unit that adjusts, in a period other than a document scanning period, a lighting period of the light source so that the light source is turned on and off alternately in a repetitive manner in units of a line cycle; a black correction unit that generates reference black data used for black correction based on effective pixel data in a light source non-lighting period in the period other than the document scanning period; and a white correction unit that generates shading data used for shading correction based on effective pixel data in a light source lighting period in the period other than the document scanning period.

Abstract: An image forming apparatus includes a main body of the image forming apparatus; at least one image forming unit disposed in the main body; a light scanning unit that is disposed in the main body and scans light to form an electrostatic latent image on a photosensitive medium of the at least one image forming unit; a window open-closing shutter that is disposed to slidably move on a surface of the light scanning unit from which light emits, and moves between an open position where a light moving path is opened and a blocking position where the light moving path is blocked; a shutter operating lever that is disposed in the main body, and activates the window open-closing shutter to be positioned at either of the open position and the blocking position; and a pressure member that is disposed in the main body and presses the shutter operating lever.

Abstract: Disclosed is an image reading controller including an output unit that outputs plural control signals for controlling turning on and off of a light emitting unit of an image reading unit including the light emitting unit and a light receiving unit on respective transmission paths, the plural control signals satisfying at least one of a first condition that respective transmission paths are separated from each other by a predetermined distance or more and a second condition that types of the respective transmission paths are different from each other; and a controller that controls turning on and off of the light emitting unit on the basis of the plural control signals output from the output unit and input through the respective transmission paths.

Abstract: Provided is a document reading apparatus capable of surely detecting the document cover open/closed state and the open/close operation, without being affected by the external environment. This document reading apparatus includes a light source, a linear reading device and a document cover. In this document reading apparatus, the light amount value of the light received by the linear reading section while the light source is turned on, and the light amount value of the light received by the linear reading section when the light source is turned off are used to detect the open/closed state and the open/close operation of the document cover, wherein the preparation for printing starts when the document cover has shifted from the open state to the closed state.

Abstract: An illumination apparatus configured to illuminate a target surface from a first side and a second side different from the first side, including: a guide; and a reflector, the guide including: incident surface; a surface for totally reflecting beam from the incident surface; a reflecting surface arranged on an opposite side of the incident surface relative to the surface; a first exit for causing the reflected beam to exit as converging beam from the first side, the first exit having condensing action in plane orthogonal to the one-dimensional direction; and a second exit, adjacent to the first exit, having condensing action in the orthogonal plane for causing beam not reflected by the reflecting surface to exit as converging beam, and the reflector reflecting the beam from the second exit to the target surface as beam from the second side.

Abstract: A light collecting member includes a lens to make incident light be collected on a light receiving member, a lens barrel to house the lens, an end portion into which a light enters of the lens barrel being arranged near the light receiving member and a fence member to cover the end portion into which a light enters of the lens barrel and the light receiving member, the fence member having an exhaust port formed in a manner extending in a vertical direction.

Abstract: An image reading apparatus includes a stacking unit on which a document to be fed is stacked, a sensor configured to output a signal indicating that the document has been stacked on the stacking unit, a discharging unit to which the document is to be discharged, wherein the discharging unit includes a lamp, and a control unit configured to turn on the lamp in response to the signal indicating that the document has been stacked on the stacking unit output from the sensor.

Abstract: An image reading device includes a platen on which an original is to be placed, an illuminating unit configured to illuminate the original, a linear sensor configured to receive light from the original, an optical unit configured to guide the light from the original to the linear sensor, and an aligning portion configured to determine a position of the original in a long-side direction of the linear sensor. The illuminating unit includes a light-guiding member extending in the long-side direction of the linear sensor, and a light source provided only at one long-side end of the light-guiding member. The aligning portion is provided on a side opposite the light source in the long-side direction of the light-guiding member.

Abstract: In an illumination device that radiates light to an object to be irradiated placed on a predetermined placement surface, a first light guide body has a first incident surface located at an end thereof in a first direction, which receives light along the first direction, and a first exit surface extending along the first direction, which emits the light in a second direction crossing the first direction, thereby radiating light to the object to be irradiated, from the second direction, and a second light guide body has a second incident surface located at an end thereof in the first direction, which receives light along the first direction, and a second exit surface extending along the first direction, which emits the light in a third direction crossing the first direction and the second direction, thereby radiating light to the object to be irradiated, from the third direction.

Abstract: Since a light emitting surface in a cross section perpendicular to the longitudinal direction of a light guide is formed to have a smaller width than a reflecting surface, light of an LED, which is incident from an end surface of the light guide and is scattered throughout the entirety of the longitudinal direction in the reflecting surface, is condensed toward the light emitting surface, and is then emitted in the form of a band toward a document from the light emitting surface. Therefore, it is possible to provide a CIS module including an illumination unit having a new configuration capable of illuminating a portion where the document and an optical axis of the lens array included in the lens unit intersect, in the form of a band with high efficiency using the illumination unit.

Abstract: An embodiment of this invention is directed to reading an original at a high resolution with high quality by an image reading apparatus using a 3-line CCD and white LED. The image reading apparatus according to the embodiment includes a 3-line CCD, a white LED, and a light guide configured to guide light from the LED to an original. A surface of the light guide from which light emerges toward the original is formed into a concave shape. Light from the light guide almost uniformly irradiates the reading region of an image placed on a platen glass.

Abstract: An image forming apparatus comprises an image sensor configured to extend in a horizontal scanning direction, a carriage, a guide section and a reading control section. The carriage configured to move in a vertical scanning direction orthogonal to the horizontal scanning direction to change a reading position of a document. The guide section configured to have a guide surface for guiding the document to the document glass, and a white part, a first colorizing part and a second colorizing part which are formed on the guide surface in line in the vertical scanning direction. The reading control section configured to move the carriage to align the reading position in the vertical scanning direction with one of the white part, the first colorizing part and the second colorizing part and execute a reading processing.

Abstract: In a method for document digitization, an apparatus generates a first image of a document sheet by irradiating the document sheet using a first light source and detecting the document sheet irradiated with light from the first light source, which enables detection of ink on the document sheet that defines a marked portion. The apparatus further generates a second image of the document sheet by irradiating the document sheet using a second light source and detecting the document sheet irradiated with light from the second light source, which enables detection of content on the document sheet. The apparatus further obtains a region of the second image that corresponds to the marked portion of the document sheet based on the first image.

Abstract: A light source driving circuit that drives a light source includes a driving electric current generator that generates a driving electric current including a predetermined electric current, a first auxiliary current, and a second auxiliary current; and a controller that sets values of the first and second auxiliary currents by using first and second lighting pattern signals, wherein each of the first and second lighting pattern signals is for controlling supply of the predetermined electric current to the light source. After setting a first value of the first auxiliary current, a second value of the second auxiliary current is set by using the second lighting pattern signal that defines a time period for stopping supply of the predetermined electric current to be shorter than a time period for stopping the supply of the predetermined electric current that is defined by the first lighting pattern signal.

Abstract: The object of the present invention is to provide a light scanning apparatus of a simple arrangement which can reduce print misregistration of respective beams in a main scanning direction in an image region even when an inexpensive imaging optical unit which forms a spot image on the image region of a surface to be scanned, and can form a high-resolution image, and an image forming apparatus using the same.

Abstract: A method of synchronization adjustment is applied to an optical detecting device, so as to synchronize an exposure timing sequence of an image detector with a light emitting timing sequence of an indicating light source. The method includes acquiring a continued image set, analyzing intensity of each image of the continued image set, and adjusting the exposure timing sequence according to duty cycle of the image detector and intensity ratio of at least two images. An exposure frequency of the image detector is greater than a flickering frequency of the indicating light source.

Abstract: An image reading lens which reads an original image includes a front group lens system on an object side, and a back group lens system on an image side, the front group lens system including three lenses having two positive lenses and a negative lens, and the back group lens system including a plastic negative lens.

Abstract: Provided are: a light source that emits light; a light guide including: a curved portion including a light incident surface from which the light from the light source enters; and a linear portion including a light emission surface from which the light is emitted to an original, the linear portion coupled to the curved portion and extended in a main-scan direction, the curved portion reflecting the light entered from the light incident surface to the linear portion; and a frame that houses the light source, and the light guide, wherein the light guide includes an inclined portion inclined in a direction that increases an incident angle ? of the light, the inclined portion formed in a range of the linear portion where the light reflected by the curved portion enters.

Abstract: A configuration is adopted in which an image sensor unit includes: a sensor substrate on which a plurality of photoelectric conversion elements are mounted; a light source that includes light-emitting elements and is for illuminating a document; a light guide that guides light from the light source from one end face in a longitudinal direction and linearly illuminates the document; a rod lens array imaging reflected light from the document on the sensor substrate; and a frame attaching each of these, and in which the frame detachably includes a spacer provided in proximity to the light source, and the spacer includes a light shielding roof elongated so as to cover the light source and the end of the light guide.

Abstract: A scanner lens includes a first lens group with a positive refractive power, having a first positive lens and a second negative lens which are cemented, second to fifth lens groups having a third negative lens, a fourth positive lens, a fifth negative lens, and a sixth negative lens, respectively, arranged in order from an object side to an image side, and an aperture stop disposed between the first and second lens groups. The scanner lens satisfies the following three conditions: 0.01<BF/L<0.10 0.50<f1/f<9.5 0.20<d10/f<0.90 where BF is a back focus of the scanner lens, L is a total lens length, f1 is a focal length of e-line of the first lens group, f is a focal length of e-line of the entire lens system and d10 is an air space between the fifth and six lenses.

Abstract: A scanning apparatus includes a scanning module, a calibration plate, and a driving module. The calibration plate includes a first background region for calibrating the brightness of the scanning module and a second background region for intensifying an edge of a document to be scanned. The driving module is used for driving movement of the calibration plate. As a consequence, the scanning light beam from the scanning module is projected onto the first background region or the second background region of the calibration plate. Under this circumstance, the purposes of calibrating the brightness and increasing the image processing efficiency are both achieved. Moreover, since the calibration plate is driven by the driving module to be moved in the direction parallel with said scanning light beam, the purpose of dynamically adjusting the brightness can be achieved.

Abstract: A light guide includes an incident surface, an emitting surface, a reflecting surface, and a light guide section. The incident surface receives light from a plurality of light-emitting elements arranged at least in a first direction. The emitting surface outputs incident light from the incident surface. The reflecting surface includes a plurality of lenses having optical power in the first direction and a second direction different from the first direction and is provided to be opposed to the incident surface. The light guide section includes a surface including the incident surface, the emitting surface, and the reflecting surface, and causes the light that has entered from the incident surface to be reflected by the plurality of lenses of the reflecting surface to guide the light to the emitting surface.

Abstract: An image reading device includes a contact glass having a document placing surface, an index part to be an index for aligning a corner of a document to a reference point within the document placing surface, a reading portion configured to read the document, and a light emitting portion configured to emit linear light extending in a main scanning direction. When a predetermined point apart from the index part within the document placing surface is set as the reference point, the light emitting portion moves in a sub-scanning direction so that a region of the contact glass irradiated with the linear light coincides with the predetermined point, and emits the linear light.