Konica Minolta, Inc.

Konica Minolta Business Technologies, Inc.

Minolta Company, Ltd.

Makoto Obayashi

Masayuki Iijima

Yoshikazu Watanabe

Takaki Uemura

Satoshi Masuda

So Yano

Takatoshi Hamada

Hidenari Tachibe

Tatsuya Eguchi

Syuji Maruta

Takafumi Yuasa

Kazuyoshi Noguchi

Wataru Senoo

Masayuki Tanaka

Masayuki Iljima

An optical scanning device that scans a photoreceptor with light, the device includes: a light emitter that emits light according to a supply current amount; a source-side optical system that includes an optical element corresponding to the light emitter, the optical element transmitting and shaping the light emitted from the corresponding light emitter; a polygon mirror that cyclically deflects the light shaped by the source-side optical system; an image-side optical system that condenses the light deflected by the polygon mirror on a surface of the photoreceptor; a motor that rotates the polygon mirror; and a light source controller that: monitors a temperature of the optical element; and adjusts the supply current amount for the light emitter or adjusts the temperature of the optical element corresponding to the light emitter to make a temperature difference between the light emitter and the corresponding optical element fall within an allowable range.

Optical scanning device and image forming device having the same

An optical print head that performs optical writing to a photoreceptor includes: a light transmissive substrate; a light emitting unit including light emitting element groups, each of which includes two or more light emitting elements disposed on a first main surface of the substrate; a lens array including lenses that correspond one-to-one to the light emitting element groups; light detection units disposed above the second main surface of the substrate in one-to-one correspondence to the light emitting element groups and that detects the light from each of the light emitting elements; and correction unit that corrects light amounts of the light emitting elements of the light emitting element group based on detection of the light detection units.

Optical print head and image forming device

A relative position detection method detecting a position of a light-emitting member relative to a lens array or a position of the lens array relative to the light-emitting member, in which the light-emitting member includes light-emitting elements arranged in a first direction and the lens array includes lenses arranged in the first direction and condenses light from the light-emitting elements to image positions of the light-emitting elements, optical axes of the lenses being orthogonal to the first direction. The method includes: causing the light-emitting elements to emit light; detecting, at a position displaced from the image positions along an optical axis direction, optical intensity distribution of light emitted from the light-emitting elements and transmitted through the lens array; and detecting a position of the light-emitting member relative to the lens array or a position of the lens array relative to the light-emitting member with use of the optical intensity distribution.

Relative position detection method, optical print head, and image forming device

An image forming apparatus including a polygon mirror that deflects a light beam includes: a light emitter that emits the light beam; an optical sensor that is disposed at a position on which the light beam deflected by the polygon mirror is incident; a detector that detects a minimum level being a light intensity level of the light beam, the lowest within a range detected by the optical sensor; a switcher that switches a light intensity level of the light beam emitted from the light emitter until the detector detects the minimum level; and a determiner that determines a degree of contamination of a component on an optical path of the light beam extending from the light emitter to the optical sensor, on the basis of the minimum level detected when the light intensity level is switched by the switcher.

Image forming apparatus

A print head for writing data onto a photoreceptor, including a light source panel of light emitting elements arranged in a matrix, optical systems arranged in a matching matrix, light receiving elements, and a corrector. The optical systems each include at least a light-source-side lens and an image-side lens, and focus light from the light emitting elements onto different regions of the photoreceptor. The light receiving elements each include a light receiving surface disposed in a leaked light region and detect light incident on the light receiving surface. The leaked light region is in a gap between the light-source-side lens and the image-side lens of each of the optical systems occupied by optical paths of light transmitted through the light-source-side lenses but not incident on the image-side lenses. The corrector corrects amounts of light to be emitted from the light emitting elements based on the light detected.

Print head and image forming device having the same

An image forming device includes: a photoreceptor; a longitudinal light emitting member constituted from light emitting element rows that are arranged in a lateral direction and are each constituted from light emitting elements arranged in a longitudinal direction; an optical member that is longitudinal and is disposed to condense light emitted from the light emitting elements onto the photoreceptor; and a hardware processor that: selects and causes one or more light emitting elements for each light emitting element row to emit light; acquires an exposure amount for each light emitting element row; calculates a distribution of the exposure amounts acquired for the light emitting element rows, and calculates a position in the lateral direction corresponding to a predetermined exposure amount in the distribution; and judges whether a difference between the calculated position and a reference position in the lateral direction at a reference time is less than a threshold value.

Image forming device, control method, and recording medium

An optical print head including a light emitting member, an optical member, a detection unit, and a correction unit. The light emitting member is elongated in a longitudinal direction with light emitting elements arranged along the longitudinal direction. The optical member is elongated in the longitudinal direction with optical elements arranged along the longitudinal direction, the optical elements collecting light emitted by the light emitting elements. The detection unit detects an index value of linear expansion difference in the longitudinal direction of the light emitting member and the optical member. The correction unit uses the index value to correct an emitted light amount for each of the light emitting elements in order to offset differences in light collection efficiency caused by the linear expansion difference.

An optical writing device having; a plurality of light-emitting points; a photodiode configured to output a signal which represents a quantity of incident light from a predetermined light-emitting point selected from the plurality of light-emitting points; and a calculation section for calculating a temperature of the photodiode based on a magnitude of a photodiode dark current included in the signal output from the photodiode while the predetermined light-emitting point is OFF.

Optical writing device, image forming apparatus, and temperature calculation method

An optical writing device includes a plurality of current driven light emitting elements, first and second power source lines, a designation circuit that outputs a designation potential, first driving circuits provided for each of the light emitting elements to supply driving current to the corresponding light emitting element, second driving circuits provided for each of the light emitting elements to supply driving current to the corresponding light emitting element, and a switching control unit that alternately switches respective states of the first and second driving circuits between a state where one of the first and second driving circuits receives the designation potential while the other driving circuit supplies the driving current, and a state where the other driving circuit receives the designation potential while the one driving circuit supplies the driving current.

Optical writing device and image forming apparatus

An optical print head includes: light-emitting elements in line shape; first power line supplying first reference voltage; second power line supplying drive current to each light-emitting element and supplying second reference voltage; DAC outputting first voltage indicating light emission amount of each light-emitting element; first elements for holding first voltage difference between the first reference voltage and the first voltage; second elements each electrically connectable with corresponding first element and for holding second voltage difference between the second reference voltage and second voltage according to the first voltage, and during supply of drive current, controls each first element to hold the first difference by electrically disconnecting the first and second elements, and temporarily suspends supply of the drive current, and controls the second element to hold the second difference by electrically connecting the first and second elements, such that the drive current according to the second voltage difference is supplied.

Optical print head and image forming apparatus

An optical print head for forming an electrostatic latent image on a photosensitive body, including: current-driven light-emitting elements disposed in a line shape; an indicator circuit that outputs indicator current indicating light emission amounts to the light-emitting elements; and for each light-emitting element: a holding circuit that, during a main scanning period, accumulates indicator current during a sample period to generate an indicator potential and holds the indicator potential during a hold period; and a drive circuit that supplies drive current to the light-emitting element according to the indicator potential, wherein each of the sample periods is divided into writing periods, and each of the holding circuits holds the indicator potential corresponding to the holding circuit according to a total of indicator current amounts in the sample period corresponding to the holding circuit, the indicator current amounts each indicative of indicator current during one of the writing periods.

An optical print head performs optical writing onto target, and includes: current-driven light-emitting elements arranged in rows in a predetermined direction; driving transistors that are each electrically series-connected with the light-emitting elements in one-to-one correspondence, and each supply a driving current to a corresponding light-emitting element; a current control unit that controls, for each light-emitting element, a driving current amount in accordance with variation in light-emitting properties of the light-emitting element that indicate relation between the driving current amount and a light amount emitted by the light-emitting element; an application unit that, upon receiving electrical power supplied from an external power source, applies application voltage to circuits each consisting of a light-emitting element and a corresponding driving transistor; and a voltage control unit that suppresses variation in divided voltage applied to each driving transistor by controlling the application unit to apply increased application voltage of the driving current amount increases.

An optical writing device having; a plurality of light-emitting points; a plurality of drive circuits for supplying drive currents to the plurality of light-emitting points respectively; a photodetector for outputting signals indicating quantities of light entering thereto from the respective light-emitting points; a gain switch circuit for outputting photodetection signals obtained by amplifying the signals output from the photodetector in regard to the respective light-emitting points with gains preset for the respective light-emitting points; and a control circuit for controlling the drive circuits such that the photodetection signals output from the gain switch circuit in regard to the respective light-emitting points coincide with a value substantially equal to a predetermined reference value. The gains for the respective light-emitting points are preset based on the distances between the photodetector and the respective light-emitting points.

Optical print head includes: light-emitting elements connected one-to-one to current supply lines branching from first power line at different positions in longitudinal direction; holding elements; signal writing unit writing luminance signal into each holding element, the luminance signal being represented by voltage indicating light emission amount of corresponding light-emitting element; second power line supplying reference voltage to each holding element, the reference voltage being reference when signal writing unit writes luminance signal into holding element; and driving drivers corresponding one-to-one with current supply lines and controlling current supplied to corresponding current supply line from first power line, in accordance with voltage held in corresponding holding element when signal writing unit has written luminance signal into corresponding holding element, wherein power source supplying the reference voltage to second power line is common with power source supplying voltage to signal output subunit outputting luminance signal.

Optical print head having first and second power lines and image forming apparatus

An optical writing device for forming an electrostatic latent image on a photoreceptor by exposing the photoreceptor to light modulated in accordance with image data. The optical writing device has: a substrate; a light-emitting-element array including a plurality of light-emitting elements supported by the substrate to be arranged in a main-scanning direction; and a light-receiving-element array substantially in parallel to the light-emitting-element array, the light-receiving-element array including a plurality of light-receiving elements supported by the substrate to be arranged in the main-scanning direction. For light-quantity measurement of one of the light-emitting elements, at least an output value output from one of the light-receiving elements of which center is located in a different position, with respect to the main-scanning direction, from a center of the one of the light-emitting elements is used.

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Toyokawa, Japan

Makoto Obayashi