Abstract: One aspect of this invention relates to an illumination device for an optical printer, the illumination device comprising: a first array of light sources comprising a plurality of light source elements that are each operable to emit light within a red band of the visible electromagnetic spectrum; a second array of light sources comprising a plurality of light source elements that are each operable to emit light within a blue band of the visible electromagnetic spectrum; and a third array of light sources comprising a plurality of light source elements that are each operable to emit light within a green band of the visible electromagnetic spectrum; wherein said first, second and third arrays of light sources are generally linearly arranged along respective substantially parallel notional lines on a substrate; and said plurality of light source elements of each said array are arranged such that respective adjacent light source elements of said plurality are offset from one another with respect to the associated

Abstract: An exposure device for exposing a photoreceptor, includes: data electrodes disposed for each of a plurality of columns parallel to a moving direction of the photoreceptor; selected electrodes disposed for each of a plurality of rows perpendicular to each of the data electrodes; light emitting element arrays including light emitting elements disposed near intersection points between the data electrodes and the selected electrodes in intersections between the data electrodes and the selected electrodes, the light emitting elements being linearly arrayed; a driving signal output circuit for generating a driving signal based on an image signal to supply the driving signal to the light emitting element arrays; and a column selection unit for switching the light emitting element arrays to be selected based on a lighting situation of each of the light emitting elements of each of the light emitting element arrays.

Abstract: A recording head (16) is operated to form a regular pattern of image swaths on a recording media (17). The regular pattern of image features comprises a first set of image features (60A) that is formed with an imaging parameter set to a first predetermined value and a second set of image features (60B) is formed with an imaging parameter set to a second predetermined value, different from the first predetermined value. Image features in the first set and the second set are arranged on the recording media with a sub-scan spatial frequency equal to a non-integer multiple of a sub-scan spatial frequency of the image swaths. A scanner (40) generates data (47) of the scanned pattern, wherein a first integer multiple of a sampling spatial frequency employed by the scanner is equal to a second integer multiple of the sub-scan spatial frequency of the first set and the second set of image features.

Abstract: An optical device includes at least one surface emitting laser device having a dielectric film for causing a central portion of a light emitting region to have a comparatively higher reflectivity than a peripheral portion; a light receiving element disposed, with respect to a first direction, on one side to the surface emitting laser device; and a transparent member disposed in a path of light emitted from the surface emitting laser device and configured to reflect a portion of the light toward the light receiving element as monitoring light. The central portion has shape anisotropy in which a width measured on a line extending in the first direction and passing through the center of the light emitting region is smaller than a width measured on a line extending in a second direction, which is perpendicular to the first direction, and passing through the center of the light emitting region.

Abstract: A disclosed surface-emitting laser element includes a substrate, multiple semiconductor layers stacked on the substrate including a resonator structure including an active layer, a semiconductor multilayer mirror on the resonator structure, and a confined structure where a current passage region is enclosed by at least an oxide generated by oxidation of part of a selective oxidation layer containing aluminum, an electrode provided around an emission region, and a dielectric film provided in a peripheral portion within the emission region and outside a central portion of the emission region to make a reflectance of the peripheral portion lower than that of the central portion. The dielectric film is arranged such that a reflectance of a high-order transverse mode in a second direction is higher than that in a first direction, and a width of the current passage region in the first direction is greater than that in the second direction.

Abstract: An optical scanning device is configured in such a manner that, of four light beams for colors corresponding to cyan, magenta, yellow, and black, the number of folding mirrors disposed in the optical path of a light beam corresponding to an mage in yellow having the highest brightness and the lowest visibility is the greatest number, and further, the number of the folding mirrors disposed in the optical path of a light beam corresponding to an image in black having the lowest brightness and the highest visibility is the least number. It is thus possible to reduce unevenness in color in the color image resulting from the folding of light beams by the folding mirrors.

Abstract: A light-emitting unit having an arrayed light source comprises a substrate; an arrayed light source group containing the arrayed light source arranged in a first direction; a lens array for focusing the light emitted from light emitting elements constituting the arrayed light source; and a lens support having a cavity formed between arrayed light source group and the lens array; the lens support having a first hole for introducing a fluid into the cavity, and a second hole for discharging the introduced fluid in a second direction crossing the first direction.

Abstract: A light-emitting element includes a cathode, an anode, a luminescent layer disposed between the cathode and the anode, a first electron transport layer disposed between the luminescent layer and the cathode, and a second electron transport layer in contact with the luminescent layer and the first electron transport layer between the luminescent layer and the first electron transport layer. The luminescent layer contains a red luminescent material emitting red light. The first electron transport layer contains a first electron transport material. The second electron transport layer contains a second electron transport material different from the first electron transport material.

Abstract: A surface-emitting laser element for emitting light in a direction perpendicular to a substrate, including a substrate with a normal direction of a principal plane inclining toward one direction of <1 1 1> with respect to one direction of <1 0 0> and a mesa structure formed on the substrate and having a narrowed structure with an oxide produced by oxidizing a part of a layer to be oxidized selectively, containing aluminum and surrounding an electric current passage area, wherein a cross-section of mesa structure being parallel to the substrate is parallel to a substrate surface and orthogonal to both one direction of <1 0 0> and one direction of <1 1 1> and a length in a first direction passing through a center of the electric current passage area is more than a length in a second direction parallel to a substrate surface and orthogonal to the first direction.

Abstract: An optical device including an optical element; a package member in which the optical element is held on a bottom surface of the package member in an area surrounded by walls; and a plate member that seals the area surrounded by the walls and the bottom surface in an airtight manner, the plate member being translucent and joined to the package member with a resin material. The walls have a structure including steps, the plate member is joined onto one of the steps of the walls, and at least a part of the walls facing side surfaces of the plate member includes a positioning part for positioning the plate member and a retaining part for retaining the resin material, in a direction perpendicular to the bottom surface.

Abstract: A pixel information acquiring unit acquires multilevel pixel information in which one pixel is expressed in multilevel scales. A line pixel information storing unit stores the multilevel pixel information for each main scanning line. A light emission control unit optically exposes a photosensitive element by controlling a binary light source on the basis of the multilevel pixel information. The photosensitive element is exposed to the binary light source with a period corresponding to N-fold in a sub scanning direction resolution of the multilevel pixel information, wherein N is a positive integer, so that the N times exposures corresponds to an exposure for one pixel in an original resolution. The switch on/off statuses of the binary light source are controlled in the N times exposures for each pixel, on the basis of lighting rate information for converting the multilevel scales into a lighting rate in the N times exposures.

Abstract: An image forming apparatus includes a photoconductive body on which an electrostatic latent image is formed; an exposure member which has a plurality of blinking sections and which exposes the photoconductive body; a support frame which is made of resin and which supports the exposure member; a roller shaft which is made of metal and provided on the support frame; a roller which is made of resin, which is rotatably provided on the roller shaft and which maintains a spacing distance between the exposure member and the photoconductive body; and a metal plate which supports and is electrically connected to the roller shaft and which is electrically grounded. With the image forming apparatus, it is possible to solve a problem caused when the roller shaft is electrically floated, and to suitably arrange parts or components around the roller shaft.

Abstract: A semiconductor device includes a substrate, and a semiconductor thin film bonded to the substrate, wherein the semiconductor thin film includes a plurality of discrete operating regions and an element isolating region which isolates the plurality of discrete operating regions, and the element isolating region is etched to a shallower depth than a thickness of the semiconductor thin film, and is a thinner region than the plurality of discrete operating regions.

Abstract: A light emitting substrate has a plurality of first light emitting portions arranged in a main scanning direction and a second light emitting portion disposed in a direction intersecting the main scanning direction with respect to the array of the plurality of first light emitting portions. A lens array has a plurality of first lenses, each of which is disposed to face each of the plurality of first light emitting portions, and a second lens for the second light emitting portion. A direction of the emitted light from the second light emitting portion has a slope with respect to a straight line which extends perpendicularly from a light emitting face of the corresponding second light emitting portion.

Abstract: A light emitting head for use in copiers or printers, the light emitting head having an illuminated length, e.g.

Abstract: An optical unit includes an optical element having a first combining surface and a second combining surface that applied an adhesive that is cured when exposed to a curing light respectively and that have different transmittance of the curing light; and a mount member combined with the optical element by the adhesive. The adhesive is cured when exposed to the curing light.

Abstract: In a method of manufacturing a semiconductor thin film piece device, a plurality of semiconductor thin film pieces (14) are selected from among the semiconductor thin film pieces (14) formed on a first substrate (35), and bonded to a first set of predetermined area on a second substrate (12). Subsequently, a plurality of semiconductor thin film pieces are selected from the remaining semiconductor thin film pieces (14), and bonded to a second set of predetermined area.

Abstract: A light-emitting device includes: a board; plural light-emitting chips that are one-dimensionally arrayed in a longitudinal direction of the board and that are connected to a first potential and a second potential; and plural capacitors that each include a first electrode and a second electrode arranged in a short-side direction of the board, and that are arrayed in the longitudinal direction of the board so that the first electrode and the second electrode are alternately positioned between each adjacent two of the capacitors. The first electrode is connected to the first potential for the light-emitting chips, and the second electrode is connected to the second potential for the light-emitting chips.

Abstract: A print head, including: a plurality of chips disposed in a linear array; respective pluralities of first and second matrix drivers on each the chip connected to first and second channels, respectively; and for each chip, first groups of light-emitting diodes (LEDs). Each first group of LEDs includes: a second group of LEDs, with a first number of LEDs, connected to a respective first matrix driver; and a third group of LEDs, with the first number of LEDs, connected to a respective second matrix driver. LEDs in each first group of LEDs are disposed in a staggered arrangement; and the respective pluralities of first and second matrix drivers are for activating in sequence the LEDs in the second and third groups of LEDs, respectively.

Abstract: An optical scanning unit may include a light source unit configured to emit a light beam, an optical housing configured to receive and support the light source unit, an optical device configured to deflect the light beam and to focus the light beam on a light receiving member, and a fixing member configured to fix the light source unit to the optical housing by applying pressure to the light source unit, wherein the pressure is applied in a direction, which is substantially perpendicular to an optical axis direction of the light source unit.

Abstract: A light emitting diode (LED) print head arranged to receive a set of raw print data. The print head includes a plurality of LED array chips each having a plurality of LEDs, wherein each LED of the plurality of LEDs includes a process direction position. The print head further includes at least one matrix drive circuit arranged to control activation of the plurality of LEDs in response to the set of raw print data and at least one real-time print data compensation circuit, wherein the at least one real-time print data compensation circuit receives the set of raw print data and delays transmitting the set of raw print data to the at least one matrix drive circuit based on a relative relationship between the process direction position of each LED.

Abstract: A light-emitting device includes: light-emitting chips each including light-emitting elements and memory elements corresponding to each other, each memory element memorizing a light-emitting element to light up, each light-emitting chip being capable of lighting up the light-emitting elements in parallel; a unit to transmit an enable signal in common to light-emitting chips belonging to each of M groups obtained by dividing the light-emitting chips, the enable signal enabling selection of light-emitting elements to light up; a unit to transmit a write signal in common to light-emitting chips belonging to each of N classes obtained by dividing the light-emitting chips, the write signal setting memory elements corresponding to the light-emitting elements to light up, to a memory state or not, in the light-emitting chips where the selection is enabled; and a unit to transmit light-up signals for lighting up to light-emitting elements corresponding to memory elements in the memory state.

Abstract: A control method of a line head including a first image forming system; a first light emission element which emits light for forming an image by an image forming lens of the first image forming system; a second image forming system disposed in a first direction of the first image forming system; and a second light emission element which emits light for forming an image by an image forming lens of the second image forming system is disclosed. The method includes, when the first light emission element emits light at a time t0 and then emits light after a time t1 from the time t0, and also when the second light emission element emits light after a time t2 from the time t0, controlling the time t1 and the time t2 such that t2?n·t1 (n: 2 or larger integer) holds.

Abstract: A light scanning apparatus having plural light sources includes a light source control unit configured to control the light sources to form L (L?2) light beam arrays aligned in a sub scanning direction each of which L light beam arrays are formed by causing M ((N?1)?M?1) light sources out of N (N?2) light sources assigned to each of the L light beam arrays to emit light as M light emitting sources, wherein each of the L light beam arrays forms a pixel and a total of L pixels aligned in the sub scanning direction are formed.

Abstract: An exposure device includes a substrate on which a light emitting element array is provided, a focusing lens that focuses light emitted by the light emitting element array, a supporting member that supports the substrate and the focusing lens. The supporting member has a contact surface. A base is provided for forcing the substrate against the contact surface of the supporting member. The base has a first engaging portion that engages a second engaging portion formed on an inner wall of the supporting member. The base is mounted to the supporting member by the engagement of the first engaging portion and the second engaging portion.

Abstract: A light-emitting device includes: a substrate; a reflection layer that is provided on the substrate, and that reflects light in a wavelength band set in advance; and a light-emitting layer that is provided on the reflection layer, and that includes a light-emitting region emitting light having wavelengths overlapping in the wavelength band and a surface having unevenness at plural distances from the reflection layer. The surface is provided on a side opposite to the reflection layer across the light-emitting region. The plural distances are set so that wavelengths forming standing waves depending on each of the distances in the wavelength band are interposed each other.

Abstract: An optical writing device includes: a light source including arrays arranged in a main scanning direction, each array including light-emitting elements arranged in the main scanning direction; a correction-value holding unit to hold, correspondingly with a light-emitting element, a correction value for changing timing to read out pixel data stored in an image storage unit; and a light-source drive unit to drive the light source by reading out the stored pixel data stored, according to the correction value. The correction-value holding unit includes a first area for holding a first correction value corresponding to a first light-emitting element located at an end of an array and a second area for holding a second correction value corresponding to a second light-emitting element other than the first light-emitting element, the first holding area being larger than the second holding area.

Abstract: An optical printer head comprises a base, a light-emitting device array mounted on the base, a lens array placed above the light-emitting device array; and a support member including a base bonding surface to which the base is bonded and a through hole, an opening of the through hole being positioned at the base bonding surface, wherein the base is bonded to the base bonding surface through an adhesive member and a part of the adhesive member is attached to an inner surface of the through hole.

Abstract: An image forming apparatus is provided, which includes: a photosensitive member; an exposure member; a support frame supporting the exposure member; a gap keeping member; a pressing member; and an adjustment member. The adjust member is disposed between the exposure member and the support frame and configured to adjust a gap between the exposure member and the support frame to allow the exposure member to move in an optical axis direction.

Abstract: An imaging head (404) for writing an image on a substrate (108) includes an array of emitters (104) comprised of groups of emitters (120, 116, 112); imaging lens (408) that focuses light from each group onto the substrate; and wherein light from each group is focused at a different depth relative to a surface of the substrate.

Abstract: A recording head including: a non-electrically conductive support member; a base board provided above the support member, the base board being provided with light emitting elements for forming an image on a recording medium, a drive section for causing the light emitting elements to emit light, a first earth connection member provided at an end portion of the base board, and a second earth connection member provided at a location of a connection member, having one end connected to a control section for controlling the drive section and another end connected to drive section; a conducting member provided at a predetermined place relative to the support member and connected to an earth; a first conduction section conducting between the conducting member and the first earth connection member; and a second conduction section conducting between the conducting member and the second earth connection member.

Abstract: An image forming apparatus includes a photoconductive body on which an electrostatic latent image is formed, an exposure unit which exposes the photoconductive body, a first pressing member which presses the exposure unit toward the photoconductive body, a first positioning member which makes a contact with the exposure unit, a second positioning member which is arranged at a side nearer to the photoconductive body than the first positioning member in an optical axial direction of light, and a second pressing member which presses the exposure unit toward the second positioning member. A point of action at which the first pressing member presses the exposure unit is positioned at a side nearer to the photoconductive body, than the first positioning member in the optical axial direction. It is possible to suppress a degradation of an image quality by suppressing an effect of vibrations with respect to the exposure unit.

Abstract: An aspect of the present invention is an LED print head grounding structure including: an LED print head that emits exposure light; a conductive member that is adjacent to one end and another end of the LED print head; a conducting portion that puts the one end of the LED print head and one end of the conductive member into electric conduction; and a grounding portion that grounds the other end of the LED print head and another end of the conductive member.

Abstract: An image forming apparatus includes an image carrier having a curvature in a first direction; and an exposure head including a first light emitting element that emits a light having a wavelength ?11 and a light having a wavelength ?12, a first optical system that converges each of the light emitted from the first light emitting element onto the image carrier, a second light emitting element, and a second optical system that converges a light emitted from the second light emitting element onto the image carrier, wherein a position at which the first optical system converges each of the light and a position at which the second optical system converges the light are different from each other with respect to the first direction.

Abstract: An image forming apparatus in which a BD signal, which is a main-scanning reference signal, and image data are input to an image signal generating unit. Using a converting unit, main-scanning coordinate information, output from a main scanning coordinate measuring counter, and correction amounts, recorded in a correction amount LUT, are referred to, to convert a proper amount of image data. Here, the converting unit performs calculations in accordance with the main-scanning coordinate information, to obtain the image data of correction amounts that differ in accordance with coordinates. The correction amounts are in correspondence with different amounts of driving current in a main-scanning direction. Therefore, laser light emission, which provides a light quantity in accordance with the image data, is controlled.

Abstract: A line head includes first to third light-emitting elements arranged in a first direction; and an optical system that forms images by light emitted from the first to third light-emitting elements on an imaging surface to form images of the light-emitting elements, in which the first light-emitting element is arranged between the second light-emitting element and the third light-emitting element in the first direction; the optical system has a first lens surface that has refractive power and is arranged so as to satisfy a relation of H>0.

Abstract: An optical writing device performs writing on an exposure region of a light writing display medium. The optical writing device includes an accommodation section, a light irradiation member, a voltage application member, a medium conveyance member and control means. The control means performs control for: applying voltage with the voltage application member to a first medium; the light irradiation member irradiating the light bearing image information and moving a first distance in the first direction over the first medium; the voltage application member applying voltage to a second medium; the light irradiation member irradiating the light for image erasure onto the second medium and moving a second distance in the second direction over the second medium; and, simultaneously the movement of the light irradiation member in the second direction, the medium conveyance member conveying the first medium.

Abstract: A method and apparatus are provided for evaluating the severity in a printed image of a repeating band print artifact. After electronically capturing the printed image, each of a plurality of patches taken from captured image is analysed to produce an artifact severity measure for the patch; an overall artifact severity value is then determined for the printed image from the patch severity measures. The analysis of each patch involves producing a spatial intensity profile across the patch substantially at right angles to an expected direction of extent of any repeating band print artifact present; a Fourier-related transform is then applied to the spatial intensity profile and the patch artifact severity measure generated by summing the resultant spatial frequency coefficients in a limited range about a frequency of interest.

Abstract: A novel semiconductor article manufacturing method and the like are provided. A method of manufacturing a semiconductor article having a compound semiconductor multilayer film formed on a semiconductor substrate includes: preparing a member including an etching sacrificial layer (1010), a compound semiconductor multilayer film (1020), an insulating film (2010), and a semiconductor substrate (2000) on a compound semiconductor substrate (1000), and having a first groove (2005) which passes through the semiconductor substrate and the insulating film, and a semiconductor substrate groove (1025) which is a second groove provided in the compound semiconductor multilayer film so as to be connected to the first groove, and bringing an etchant into contact with the etching sacrificial layer through the first groove and then the second groove and etching the etching sacrificial layer to separate the compound semiconductor substrate from the member.

Abstract: An erect equal-magnification lens array according to the present invention includes: a first lens array plate including a first lens plate and a group of plural convex lenses arrayed on an emission surface of the first lens plate, an incident surface of the first lens plate being formed in a planar shape; a first aperture plate having plural apertures; a second lens array plate including a second lens plate and a group of plural convex lenses arrayed on both an incident surface and an emission surface of the second lens plate; a second aperture plate including plural apertures corresponding to plural projections of the plural convex lenses on the emission surface of the second lens plate; and a third lens array plate including a third lens plate and a group of plural convex lenses arrayed on an incident surface of the third lens plate.

Abstract: A scanning laser having a wavelength compatible with a coating binder so as to cure it as the laser scans and irradiates the coating on a moving web. A system and method for curing flakes by providing a scanning laser which scans across a moving coated substrate in a magnetic field allows images to be formed as magnetically aligned flakes are cured into a fixed position. The images have regions of cured aligned flakes. The scanning laser cures the magnetically aligned flakes within it region it irradiates. Alternatively an array of lasers can be used wherein individual lasers can be switched on and off to fix irradiated coating as a moving web is moved at a high speed.

Abstract: The light-emitting device includes: light-emitting elements linearly arrayed at intervals corresponding to a first resolution; switch elements electrically connected to the light-emitting elements; a transfer signal supply unit supplying a transfer signal for transmitting an on state among the switch elements by alternately repeating operations of turning on one switch element and turning on two adjacent switch elements including the one switch element; and a light-emission signal supply unit supplying a light-emission signal corresponding to a second resolution being a half of the first resolution, at supply timing changed according to whether in a first mode for causing an odd-numbered light-emitting element and a next even-numbered one to emit light as a pair, or the second mode for causing an even-numbered light-emitting element and a next odd-numbered one to emit light as a pair, the light-emitting elements arrayed at positions corresponding to the numbers.

Abstract: The light-emitting device includes: a setting unit switching a potential difference between anode and cathode electrodes alternately between first and second potential differences so that light-emitting thyristors are caused to have one of the first and second potential differences in common; a specifying unit sequentially specifying, as a target for controlling, one light-emitting thyristor; a supply unit alternately supplying transition voltage for causing specified light-emitting thyristor to transition from the off state to the on state and maintaining voltage for keeping the thyristor being in the off state to a gate electrode of the thyristor, in a light-emission control period during which the specifying unit specifies the target and the setting unit sets the second potential difference; and an adjusting unit that adjusts a light-emitting period of the one light-emitting thyristor by supplying the maintaining voltage and stopping supplying the voltage at a variable timing, in the light-emission control

Abstract: A line head includes multiple light emitting element groups each including multiple light emitting elements. In each light emitting element group, the multiple light emitting elements are disposed in a two-dimensional arrangement so that a distance Gx is greater than a distance Gy. The light emitting element groups are arranged so that pitches Px are greater than pitches Py.

Abstract: The light-emitting element head is provided with: plural light-emitting element chips in each of which light-emitting elements are arrayed in a line; a lighting signal supply unit supplying lighting signals for setting whether or not the light-emitting elements emit light, each of the lighting signals being provided in common to the light-emitting element chips that belong to one of N groups into which the plural light-emitting element chips are divided, where N is an integer of 2 or more; and a clock signal supply unit supplying a first clock signal as a transfer signal for causing the light-emitting elements to sequentially emit light, and second clock signals for setting the light-emitting elements ready to emit light, the second clock signals being different from one another, being supplied to the respective light-emitting element chips belonging to the one of the N groups, and being supplied in common across the N groups.

Abstract: An image forming apparatus includes a latent image carrier on which a latent image is formed; and a line head. The line head includes light-emitting elements arranged in a first direction; an aperture diaphragm; and an optical system that images light emitted from the light-emitting elements on a latent image carrier. The aperture diaphragm and the optical system are arranged in a second direction that is orthogonal to or substantially orthogonal to the first direction; and among the lenses included in the optical system, a lens located at the position closest to the aperture diaphragm is a multifocal lens.

Abstract: An optical system of a line head images light emitted from first and second light emitting elements and includes a rotationally symmetric lens having a lens face. A first region of the lens face includes an intersection point of the lens face with the symmetry axis of the lens, and a second region surrounding a periphery of the first region. The shape of a boundary portion between the first and second regions has the relationship 0.5?<??, wherein ? is a first direction angle that a first chief ray emitted by the first light emitting element makes with a second chief ray emitted by the second light emitting element, and ?? is an angle that a tangent line to the first region at the boundary portion makes with a tangent line to the second region at the boundary portion in a first direction cross-section including the symmetry axis.

Abstract: An exposure head includes: a group of light emitting elements in which light emitting elements are arranged in a first direction; a light emitting element substrate in which the group of light emitting elements is arranged in the first direction and in a second direction orthogonal or substantially orthogonal to the first direction; and a driving substrate which drives the light emitting elements arranged on the light emitting element substrate, wherein the driving substrate controls a light emission intensity of a light emitting element that is near to an end side in the first direction of the group of the light emitting elements, among the light emitting elements constituting the group of the light emitting elements, so that the intensity is smaller than the light emission intensity of a light emitting element constituting the group of the light emitting elements different from the above light emitting element, and the light emission intensity becomes smaller towards the end side.

Abstract: A surface-emitting laser array includes a plurality of light emitting parts arranged in a two-dimensional formation having two orthogonal directions. When the plurality of light emitting parts are orthogonally projected on a virtual line parallel to one of the two orthogonal directions, a spacing between two of the plurality of light emitting parts along the virtual line is equal to an integral multiple of a predetermined value. The plurality of light emitting parts include a first light emitting part, a second light emitting part adjacent to the first light emitting part, and a third light emitting part adjacent to the second light emitting part, and a spacing between the first and second light emitting parts differs from a spacing between the second and third light emitting parts.

Abstract: Disclosed are a print head and an image forming apparatus employing the same. The print head, which irradiates light to multiple locations of a photosensitive medium to form pixels of electrostatic latent image, includes an array of light sources corresponding to the pixels, a distributed Bragg reflector disposed adjacent the surface of the light source array from which the light source array output light, and a light focusing unit which focuses the light that have passed through the distributed Bragg reflector onto the locations of photosensitive medium.