Abstract: A power supply apparatus includes a power supply configured to apply an alternating current to a magnetic field generation apparatus; and a controller configured to control the alternating current applied by the power supply. The controller controls the power supply to apply the alternating current having a waveform pattern including a plurality of current waveforms having different frequency spectrums from each other.

Abstract: A power supply apparatus includes a power supply configured to apply an alternating current to a magnetic field generation apparatus; and a controller configured to control the alternating current applied by the power supply. The controller controls the power supply to apply the alternating current having a waveform pattern including a plurality of current waveforms having different frequency spectrums from each other.

Abstract: A power supply apparatus includes a power supply configured to apply an alternating current to a magnetic field generation apparatus; and a controller configured to control the alternating current applied by the power supply. The controller controls the power supply to apply the alternating current having a waveform pattern including a plurality of current waveforms having different frequency spectrums from each other.

Abstract: A fixing device includes a heating body; first and second coils for induction heating that heat the heating body by an induction heating method; a first switching element connected to the first coil for induction heating; a second switching element connected to the second coil for induction heating; a driving signal transmission unit that sends a first drive signal to the first switching element and a second drive signal to the second switching element so that the first switching element and the second switching element operate at the same timing to apply a first input voltage to the first coil for induction heating and a second input voltage to the second coil for induction heating; and a voltage drop unit that steps down the first input voltage applied to the first coil for induction heating so that the first input voltage is lower than the second input voltage.

Abstract: A fixing device which heats a heating object through induction heating by using a plurality of coils includes a plurality of coil drivers that drive the plurality of coils respectively, a drive circuit that controls ON/OFF states of a plurality of switching elements simultaneously to control the drive of the plurality of coil drivers, a control unit that controls a voltage supplied to each of the plurality of coils in accordance with the control of the ON/OFF states of the plurality of switching elements by the drive circuit, and a plurality of voltage control circuits that individually change the voltages supplied to the plurality of coils in accordance with the voltage control of the control unit.

Abstract: An optical sensor unit includes: a light-emitting device; a light-receiving device that receives light which is emitted from the light-emitting device and reflected from an object to be detected, and outputs an output value in accordance with the light; a shutter member that openably and closably covers an incident/exit plane having an exit part where light of the light-emitting device is emitted to the object to be detected and an incident part where light reflected from the object to be detected enters, and has a facing surface facing the incident/exit plane that is an inclined surface inclined to the incident/exit plane; and a corrector that corrects an output value of the light-receiving device when receiving light reflected from the object to be detected, based on an output value of the light-receiving device obtained by emitting light to the inclined surface of the shutter member.

Abstract: A fixing device includes a heating body; first and second coils for induction heating that heat the heating body by an induction heating method; a first switching element connected to the first coil for induction heating; a second switching element connected to the second coil for induction heating; a driving signal transmission unit that sends a first drive signal to the first switching element and a second drive signal to the second switching element so that the first switching element and the second switching element operate at the same timing to apply a first input voltage to the first coil for induction heating and a second input voltage to the second coil for induction heating; and a voltage drop unit that steps down the first input voltage applied to the first coil for induction heating so that the first input voltage is lower than the second input voltage.

Abstract: A photosensor includes a light emitting element to emit light to a target object, a light receiving element to receive the light emitted from the light emitting element and reflected by the target object, and a circuit board on which the light emitting element and the light receiving element are mounted, including at least one protrusion thereon. The light emitting element and the light receiving element each have a terminal. The at least one protrusion is configured to support one of the light emitting element and the light receiving element in a contact manner in a state that the terminal is electrically connected to the circuit board.

Abstract: An image position detector includes a light emitting element to emit light to an image on an image carrier, a first light receiving element to receive a specular reflection of light from a surface of the image carrier and output a first light receiving signal, and a second light receiving element to receive a diffuse reflection of light from a surface of the image and output a second light receiving signal. The image position detector is configured to find the end position of the image according to a multiplied value obtained by multiplying values of the first and second light receiving signals by a constant coefficient.

Abstract: A fixing device which heats a heating object through induction heating by using a plurality of coils includes a plurality of coil drivers that drive the plurality of coils respectively, a drive circuit that controls ON/OFF states of a plurality of switching elements simultaneously to control the drive of the plurality of coil drivers, a control unit that controls a voltage supplied to each of the plurality of coils in accordance with the control of the ON/OFF states of the plurality of switching elements by the drive circuit, and a plurality of voltage control circuits that individually change the voltages supplied to the plurality of coils in accordance with the voltage control of the control unit.

Abstract: A reflective photosensor detects a target object. The photosensor includes a transparent circuit board, a light emitter and a light receiver on one surface of the circuit board, including a light emitting element and a light receiving element, respectively, and disposed so that the light emitting element and the light receiving element face the one surface, a concave portion on the other surface of the circuit board, including a first refractive face to oppose the light emitting element and refract light from the light emitting element to the light receiving element and a second refractive face to oppose the light receiving element and refract, to the light receiver, a component of the light refracted by the first refractive face and specularly reflected by the target object.

Abstract: A photosensor includes a light emitting element to emit light to a target object, a light receiving element to receive the light emitted from the light emitting element and reflected by the target object, and a circuit board on which the light emitting element and the light receiving element are mounted, including at least one protrusion thereon. The light emitting element and the light receiving element each have a terminal. The at least one protrusion is configured to support one of the light emitting element and the light receiving element in a contact manner in a state that the terminal is electrically connected to the circuit board.

Abstract: A reflective photosensor detects a target object. The photosensor includes a transparent circuit board, a light emitter and a light receiver on one surface of the circuit board, including a light emitting element and a light receiving element, respectively, and disposed so that the light emitting element and the light receiving element face the one surface, a concave portion on the other surface of the circuit board, including a first refractive face to oppose the light emitting element and refract light from the light emitting element to the light receiving element and a second refractive face to oppose the light receiving element and refract, to the light receiver, a component of the light refracted by the first refractive face and specularly reflected by the target object.

Abstract: An optical sensor unit includes: a light-emitting device; a light-receiving device that receives light which is emitted from the light-emitting device and reflected from an object to be detected, and outputs an output value in accordance with the light; a shutter member that openably and closably covers an incident/exit plane having an exit part where light of the light-emitting device is emitted to the object to be detected and an incident part where light reflected from the object to be detected enters, and has a facing surface facing the incident/exit plane that is an inclined surface inclined to the incident/exit plane; and a corrector that corrects an output value of the light-receiving device when receiving light reflected from the object to be detected, based on an output value of the light-receiving device obtained by emitting light to the inclined surface of the shutter member.

Abstract: An image position detector includes a light emitting element to emit light to an image on an image carrier, a first light receiving element to receive a specular reflection of light from a surface of the image carrier and output a first light receiving signal, and a second light receiving element to receive a diffuse reflection of light from a surface of the image and output a second light receiving signal. The image position detector is configured to find the end position of the image according to a multiplied value obtained by multiplying values of the first and second light receiving signals by a constant coefficient.