Exposure device, image forming apparatus and method for operating exposure device

An exposure device for exposing a photoreceptor, comprising:

• a plurality of data electrodes disposed for each of a plurality of columns parallel to a moving direction of the photoreceptor;
• a plurality of selected electrodes disposed for each of a plurality of rows perpendicular to each of the data electrodes;
• a plurality of light emitting element arrays which include a plurality of 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 plurality of light emitting elements being linearly arrayed;
• and
• a column selection unit for designating a selected electrode of a certain predetermined column among the plurality of selected electrodes and setting selected electrodes of the other columns to undesignated selected electrodes during image forming executed on a recording medium, for executing the image forming on the recording medium only by a light emitting element of a column connected to the designated selected electrode, and 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.

A method for operating an exposure device which exposes a photoreceptor, the exposure device including a plurality of data electrodes disposed for each of a plurality of columns parallel to a moving direction of the photoreceptor;

• a plurality of selected electrodes disposed for each of a plurality of rows perpendicular to each of the data electrodes;
• a plurality of light emitting element arrays which include a plurality of 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 plurality of light emitting elements being linearly arrayed;
• the method comprising:
• designating a selected electrode of a certain predetermined column among the plurality of selected electrodes and setting selected electrodes of the other columns to undesignated selected electrodes during image forming executed on a recording medium;
• executing the image forming on the recording medium only by a light emitting element of a column connected to the designated selective electrode;
• and
• 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.

An exposure device for exposing a photoreceptor, comprising:

• a light emission unit including a plurality of light emitting element arrays which comprise a plurality of light emitting elements which are linearly arrayed, and a plurality of first switching elements disposed so as to correspond to the plurality of light emitting elements, respectively, the light emission unit having a structure in which the light emitting element arrays are arranged in parallel;
• a driving signal output circuit for generating a driving signal based on an image signal to supply the driving signal to the light emission unit;
• and
• a column selection unit for controlling turning ON/OFF of the plurality of first switching elements for each light emitting element array to select the light emitting element array to which the driving signal is applied via the first switching elements so as to correspond to each of predetermined number of light emitting elements, among the plurality of light emitting element arrays.

An image forming apparatus for forming an image on a recording medium, comprising:

• a photosensitive drum including a photoreceptor;
• and
• an exposure device for irradiating the photoreceptor of the photosensitive drum with a light based on an image signal to expose the photoreceptor, and for executing printing on the recording medium according to the image signal, wherein the exposure device comprises:
• a light emission unit including a plurality of light emitting element arrays which comprise a plurality of light emitting elements which are linearly arrayed, and a plurality of first switching elements disposed so as to correspond to the plurality of light emitting elements, respectively, the light emission unit having a structure in which the light emitting element arrays are arranged in parallel;
• a driving signal output circuit for generating a driving signal based on an image signal to supply the driving signal to the light emission unit;
• and
• a column selection unit for controlling turning ON/OFF of the plurality of first switching elements for each light emitting element array to select the light emitting element array in which the driving signal is applied to each of the light emitting elements via the first switching elements, among the plurality of light emitting element arrays of the light emission unit.