Abstract: The apparatus includes a heating roller that generates heat for melting toner attached to a printing medium; a first induction coil that is disposed outside the heating roller and heats the heating roller by using induced current generated according to current flowing through the first induction coil; two second induction coils that are disposed at upper portions of both ends of the first induction coil and heat the heating roller by using induced current generated according to current flowing through the two second induction coils; a power supply unit that supplies current to the first induction coil and the two second induction coils; and a control unit that controls the power supply unit to supply current flowing in the same direction or different directions to the first induction coil and the second induction coils according to the size of paper fed into the heating roller.

Abstract: An induction heating type fusing device and an image forming apparatus including the fusing device. The fusing device includes a magnetic flux generator and a compressing roller outside a fusing belt, first and second fusing rollers and a nip guide inside the fusing belt. The compressing roller compresses against the first and second fusing rollers and the nip guide to form nips, while the fusing belt is disposed between the compressing roller and the first and second fusing rollers and the nip guide.

Abstract: An induction heating type fusing device and an image forming apparatus including the fusing device. The fusing device includes a magnetic flux generator and a compressing roller outside a fusing belt, first and second fusing rollers and a nip guide inside the fusing belt. The compressing roller compresses against the first and second fusing rollers and the nip guide to form nips, while the fusing belt is disposed between the compressing roller and the first and second fusing rollers and the nip guide.

Abstract: A magnetic cooling apparatus having an improved structure in which effective heat exchange may be performed by a heat transfer fluid is provided. The magnetic cooling apparatus includes at least one magnetic regenerator allowing a heat transfer fluid to pass therethrough and provided with a magnetocaloric material, a magnet to apply a magnetic field to the magnetic regenerator, and at least one high temperature heat exchanger allowing heat to be dissipated by the heat transfer fluid containing heat received from the magnetic regenerator.

Abstract: An image fusing apparatus includes a heating belt including a resistance heating layer, an insulating layer formed on an inner surface of the resistance heating layer, and a release layer formed on an outer surface of the resistance heating layer; a heating supporting roller disposed (positioned) inside the heating belt and rotating with the heating belt; a pressing roller disposed (positioned) parallel to the heating supporting roller and in contact with the outer surface of the heating belt to form a nip; and an electricity supplying member to supply electricity to the resistance heating layer of the heating belt. A thickness of paper non-contact areas of opposite side end portions of the resistance heating layer of the heating belt is the same as or thicker than the thickness of a paper contact area of a middle portion of the resistance heating layer thereof.

Abstract: Provided are an inkjet printhead and a method of driving the inkjet printhead. The inkjet printhead includes a heater configured to heat ink to produce ink bubbles, an electrode configured to apply or provide the current to the heater, and a resistor connected to the electrode and separated by a distance from the heater. The resistor having a negative temperature coefficient of resistance (NTC) that can be used to compensate for the effects that temperature has on the ejection speed and mass of ejected ink droplets produced by the inkjet printhead and that result from temperature changes that occur during the operation of the inkjet printhead.

Abstract: An induction heating type fusing device and an image forming apparatus including the fusing device. The fusing device includes a magnetic flux generator and a compressing roller outside a fusing belt, first and second fusing rollers and a nip guide inside the fusing belt. The compressing roller compresses against the first and second fusing rollers and the nip guide to form nips, while the fusing belt is disposed between the compressing roller and the first and second fusing rollers and the nip guide.

Abstract: The apparatus includes a heating roller that generates heat for melting toner attached to a printing medium; a first induction coil that is disposed outside the heating roller and heats the heating roller by using induced current generated according to current flowing through the first induction coil; two second induction coils that are disposed at upper portions of both ends of the first induction coil and heat the heating roller by using induced current generated according to current flowing through the two second induction coils; a power supply unit that supplies current to the first induction coil and the two second induction coils; and a control unit that controls the power supply unit to supply current flowing in the same direction or different directions to the first induction coil and the second induction coils according to the size of paper fed into the heating roller.

Abstract: Provided is a method of detecting a missing nozzle in a thermal inkjet printhead. The method includes: applying an input energy high enough to eject ink to a heater corresponding to a target nozzle, and applying an input energy not high enough to eject ink to a heater corresponding to a nozzle adjacent to the target nozzle; when a predetermined time passes, detecting a difference between temperatures which are measured at points spaced by a predetermined distance from each of the two heaters; and determining whether the target nozzle is missing.

Abstract: An apparatus and method for fabricating a color filter by printing pixels on a substrate using an ink jet head, optically analyzing pixel quality and controlling printing in accordance with the pixel quality. Optically analyzing may include analyzing a number of ink droplets or a transmittance of a printed pixel.

Abstract: Provided is an inkjet printer having an array type head and a method of operating the inkjet printer. The inkjet printer can include a cartridge, a reservoir, a comparator and a pump. The cartridge can have an array type head with multiple inkjet printheads and a manifold to supply ink to the inkjet printheads. Each inkjet printhead can have a temperature sensor to measure temperature. The comparator can compare a signal produced by each of the temperature sensors to a signal associated with a reference temperature. The pump can circulate ink between the reservoir and the manifold of the cartridge based on the result of the temperature comparison.

Abstract: A nozzle plate, inkjet printhead with the same and method of manufacturing the same. The nozzle plate includes at least one nozzle and has at least one heater segment disposed adjacent to the nozzle. The heater segment is configured to heat a first fraction of the circumference to a greater degree than a second fraction of the circumference. Heater segments are disposed at intervals around a circumference of the nozzle and are independently operable.

Abstract: Provided are an inkjet printhead and a method of driving the inkjet printhead. The inkjet printhead includes a heater configured to heat ink to produce ink bubbles, an electrode configured to apply or provide the current to the heater, and a resistor connected to the electrode and separated by a distance from the heater. The resistor having a negative temperature coefficient of resistance (NTC) that can be used to compensate for the effects that temperature has on the ejection speed and mass of ejected ink droplets produced by the inkjet printhead and that result from temperature changes that occur during the operation of the inkjet printhead.

Abstract: A piezoelectric inkjet printhead including a reversible shutter disposed in an ink flow path is disclosed. The inkjet printhead may includes a plurality of ink pressure chambers, a plurality of piezoelectric actuators to provide the plurality of ink pressure chambers with a driving force for ink ejection, an ink manifold to supply the plurality of pressure chambers, a plurality of restrictors disposed in the ink flow path between the manifold and the plurality of pressure chambers, a plurality of ink ejecting nozzles coupled to the plurality of pressure chambers, and a plurality of unidirectional shutters. The shutters may be disposed at respective outlets of the plurality of restrictors and may be adapted to open the restrictor when ink is supplied from the restrictor to the pressure chamber and close the restrictor and restrict or prevent the backflow of ink when ink is ejected from the pressure chamber through the nozzle.

Abstract: An inkjet printhead including a passage plate in which a manifold to supply ink and a nozzle to eject ink are formed; a first electrode and a second electrode formed on the passage plate around the nozzle to generate an ion wind by ionizing air between the first and second electrodes by a voltage that is applied between the first and second electrodes, and a third electrode and a fourth electrode to generate an electrostatic force by a voltage applied between the third and fourth electrodes, wherein the third electrode is separated from the passage plate and the fourth electrode is formed on the passage plate.

Abstract: Provided is a method of detecting a missing nozzle in a thermal inkjet printhead. The method includes: applying an input energy high enough to eject ink to a heater corresponding to a target nozzle, and applying an input energy not high enough to eject ink to a hear corresponding to a nozzle adjacent to the target nozzle; when a predetermined time passes, detecting a difference between temperatures which are measured at points spaced by a predetermined distance from each of the two heaters; and determining whether the target nozzle is missing.

Abstract: A monolithic ink-jet printhead includes a substrate having a lower ink chamber formed on an upper surface thereof, a manifold for supplying ink to the lower ink chamber formed on a bottom surface thereof, and an ink channel providing communication therebetween; a nozzle plate having a plurality of passivation layers and a metal layer sequentially stacked on the substrate, the nozzle plate having an upper ink chamber formed therein on a bottom surface of the metal layer, a nozzle in communication with the upper ink chamber formed on an upper surface of the metal layer, and a connection hole providing communication between the upper ink chamber and the lower ink chamber; a heater located between the upper ink chamber and the lower ink chamber for heating ink contained in the lower and upper ink chambers; and a conductor electrically connected to the heater to apply a current to the heater.

Abstract: In a droplet ejector and an ink-jet printhead using the same, the droplet ejector includes a fluid path through which a fluid moves, a nozzle being formed on one end of the fluid path, a volumetric structure formed in the fluid path, the volumetric structure being sensitive to an external stimulus and being capable of varying in size to eject a droplet of the fluid through the nozzle, and a stimulus generator, which applies a stimulus to the volumetric structure to vary a size of the volumetric structure.

Abstract: An ink-jet printhead includes a substrate on which an ink chamber to be supplied with ink to be ejected is formed on a front surface of the substrate, a manifold for supplying ink to the ink chamber is formed on a rear surface of the substrate, and an ink passage in communication with the ink chamber and the manifold is formed parallel to the front surface of the substrate, a nozzle plate formed on the front surface of the substrate, a nozzle formed through the nozzle plate through which ink is ejected from the ink chamber, a heater formed on the nozzle plate, and an electrode electrically connected to the heater for applying current to the heater.

Abstract: An ink-jet printhead using a laser to expel ink includes an ink chamber to be filled with ink and an ink channel to supply the ink chamber with ink, the ink chamber and the ink channel formed in a passageway plate, a cover plate provided on the passageway plate, an ink ejection hole formed through the cover plate at a position corresponding to the ink chamber, a condenser lens provided on a bottom surface of the passageway plate at a position corresponding to the ink chamber, the laser irradiating a laser beam through the condenser lens and directly onto the ink contained in the ink chamber, to generate pressurized waves that vibrate a surface of the ink which causes an ink droplet to be expelled through the ink ejection hole from the surface of the ink.