Abstract: An image forming apparatus includes a paper fiber reading unit that reads fiber properties of a paper sheet; an encryption unit that encrypts at least a part of an input image based on the fiber properties read by the paper fiber reading unit; and a printing unit that prints an encrypted image portion encrypted by the encryption unit and an image including information representing the fiber properties read by the paper fiber reading unit on the paper sheet whose fiber properties are read by the paper fiber reading unit.

Abstract: An exposure device includes plural light emitting elements that light in turn for exposure, plural driving elements that drive each of the light emitting elements and a time changing member that changes one time period of a switching signal to switch light emitting elements driven by the driving elements among the plurality of light emitting elements in turn from a reference time, depending on an image forming speed, wherein the time changing member changes the one time period from the reference time for some of the light emitting elements during one main scan, and maintains the one time period as the reference time for the remaining light emitting elements.

Abstract: According to an exposure device includes an exposure section, a lighting drive section, a first temperature detector and a second temperature detector. The exposure section has a plurality of light-emitting elements. The lighting drive section determines light-emitting energies of the respective light-emitting elements and drives to light the respective light-emitting elements in accordance with the determined light-emitting energies. The first temperature detector is provided in the exposure section. The second temperature detector is provided outside the exposure section. The lighting drive section determines the light-emitting energies of the respective light-emitting elements based on a temperature detected by the first temperature detector and a temperature detected by the second temperature detector.

Abstract: An exposure device includes a plurality of light-emitting elements, a lighting driver, a first storage, a reader, a shading correction unit and a second storage. The lighting driver drives and lights up the light-emitting elements based on image data. The first storage stores light amount unevenness correction values of the respective light-emitting elements. The reader reads the light amount unevenness correction values stored in the first storage. The shading correction unit executes shading correction for the light amount unevenness correction values read by the reader. The second storage stores correction values obtained by having the shading correction unit to execute the shading correction for the light amount unevenness correction values. The lighting driver controls light power of the respective light-emitting elements based on the correction values stored in the second storage.

Abstract: An exposure device includes plural light emitting elements that light in turn for exposure, plural driving elements that drive each of the light emitting elements and a time changing member that changes one time period of a switching signal to switch light emitting elements driven by the driving elements among the plurality of light emitting elements in turn from a reference time, depending on an image forming speed, wherein the time changing member changes the one time period from the reference time for some of the light emitting elements during one main scan, and maintains the one time period as the reference time for the remaining light emitting elements.

Abstract: An exposure device includes an exposure section and first and second signal output units. The exposure section has plural light emitting elements. The first signal output unit outputs to the exposure section a first signal for determining timings for starting and ending light emission of the respective light emitting elements. The second signal output unit outputs to the exposure section a second signal for determining as to whether the respective light emitting elements are caused to emit light for respective pixels. If light mission of the respective light emitting elements is stopped with respect to all pixels of one line in a main scanning direction, the first signal does not output to the exposure section for each group of one or plural light emitting elements that operate based on the common first signal.

Abstract: An image formation system includes a medium-pattern-information-read-unit that reads pattern information of a surface of a medium; a pattern-information-image-creation-unit that creates a pattern Information image based on the read pattern information; and a print unit that adds the pattern information image to a print image to be printed on the surface of the medium and prints the print image on the medium.

Abstract: An image forming apparatus includes a paper fiber reading unit that reads fiber properties of a paper sheet; an encryption unit that encrypts at least a part of an input image based on the fiber properties read by the paper fiber reading unit; and a printing unit that prints an encrypted image portion encrypted by the encryption unit and an image including information representing the fiber properties read by the paper fiber reading unit on the paper sheet whose fiber properties are read by the paper fiber reading unit.

Abstract: Moldable polyimide resin composition which has melt-flowability and excellent processability in addition to essential heat-resistant of polyimide and comprises an aromatic bisimide compound and polyimide to resin. A further aspects relates to, a carbon fiber reinforced polyimide resin composition which has excellent mechanical strengths and comprises a carbon fiber coated with aromatic bisimide compound on the surface and the polyimide to resin, A still further aspect relates to and a novel bisimide compound which is very useful as the aromatic bisimide compound in the composition.

Abstract: A moldable polyimide resin composition which has melt-flowability and excellent processability in addition to essential heat-resistant of polyimide and comprises an aromatic bisimide compound and polyimide resin. A further aspect relates to a carbon fiber reinforced polyimide resin composition which has excellent mechanical strengths and comprises a carbon fiber coated with aromatic bisimide compound on the surface and the polyimide resin. A still further aspect relates to a novel bisimide compound which is very useful as the aromatic bisimide compound in the composition.

Abstract: A moldable polyimide resin composition which has melt-flowability and excellent processability in addition to essential heat-resistant of polyimide and comprises an aromatic bisimide compound and polyimide resin. A further aspect relates to a carbon fiber reinforced polyimide resin composition which has excellent mechanical strengths and comprises a carbon fiber coated with aromatic bisimide compound on the surface and the polyimide resin. A still further aspect relates to a novel bisimide compound which is very useful as the aromatic bisimide compound in the composition.