Abstract: A foreign substance detection device for limiting deterioration in accuracy of foreign substance detection even if a foreign substance detection region changes. The device includes an imaging device configured to keep a region for detecting a foreign substance in an imaging range of the imaging device and a determination unit configured to determine a presence or absence of the foreign substance on the basis of a result of comparing a captured image captured by the imaging device with a reference image free of the foreign substance in the imaging range. The determination unit determines that the captured image is free of a foreign substance on the basis of the result of comparing and a prescribed first condition is satisfied, the unit executes an update process of replacing the reference image with the captured image for which the unit determines freedom of a foreign substance as an updated reference image.

Abstract: A wireless power transmission apparatus including a power transmission coil that transmits electric power; a power transmission-side resonant capacitor that is connected to the power transmission coil and that, with the power transmission coil, forms a power transmission-side resonance circuit; and a self-oscillation circuit that converts a DC voltage to an AC voltage, and that supplies the AC voltage to the power transmission coil. The wireless power transmission apparatus has a state, during power transmission, in which multiple resonance points exist in a combined resonance circuit formed by magnetic coupling of the power transmission-side resonance circuit with a power reception-side resonance circuit formed from a power reception coil and a power reception-side resonant capacitor. In the state, the self-oscillation circuit operates at the lowest frequency among the multiple resonance points.

Abstract: A wireless power transmission apparatus includes a power transmission coil that transmits electric power; a power transmission-side resonant capacitor that is connected to the power transmission coil and that, with the power transmission coil, forms a power transmission-side resonance circuit; and a self-oscillation circuit that converts a DC voltage to an AC voltage, and that supplies the AC voltage to the power transmission coil. The wireless power transmission apparatus has a state, during power transmission, in which multiple resonance points exist in a combined resonance circuit formed by magnetic coupling of the power transmission-side resonance circuit with a power reception-side resonance circuit formed from a power reception coil and a power reception-side resonant capacitor. In the state, the self-oscillation circuit operates at the highest frequency among the multiple resonance points.

Abstract: A wireless power receiving device that receives AC power from a power transmission coil included in a wireless power transmission device. The wireless power receiving device includes a power receiving coil configured to receive AC power from a power transmission coil, a power receiving-side imaging unit having an auto-focus function, and a control unit configured to cause the power receiving-side imaging unit to image a range able to be imaged by the power receiving-side imaging unit and, in a case in which a marker located at a predetermined first position on an outer surface of the wireless power transmission device is imaged by the power receiving-side imaging unit, to output relative distance information representing relative distance of the power receiving coil with respect to the power transmission coil based on a detected distance using the auto-focus function used by the power receiving-side imaging unit for imaging the marker.

Abstract: A foreign substance detection device for limiting deterioration in accuracy of foreign substance detection even if a foreign substance detection region changes. The device includes an imaging device configured to keep a region for detecting a foreign substance in an imaging range of the imaging device and a determination unit configured to determine a presence or absence of the foreign substance on the basis of a result of comparing a captured image captured by the imaging device with a reference image free of the foreign substance in the imaging range. The determination unit determines that the captured image is free of a foreign substance on the basis of the result of comparing and a prescribed first condition is satisfied, the unit executes an update process of replacing the reference image with the captured image for which the unit determines freedom of a foreign substance as an updated reference image.

Abstract: A wireless power transmission apparatus includes a power transmission coil that transmits electric power; a power transmission-side resonant capacitor that is connected to the power transmission coil and that, with the power transmission coil, forms a power transmission-side resonance circuit; and a self-oscillation circuit that converts a DC voltage to an AC voltage, and that supplies the AC voltage to the power transmission coil. The wireless power transmission apparatus has a state, during power transmission, in which multiple resonance points exist in a combined resonance circuit formed by magnetic coupling of the power transmission-side resonance circuit with a power reception-side resonance circuit formed from a power reception coil and a power reception-side resonant capacitor. In the state, the self-oscillation circuit operates at the highest frequency among the multiple resonance points.

Abstract: A wireless power transmission apparatus including a power transmission coil that transmits electric power; a power transmission-side resonant capacitor that is connected to the power transmission coil and that, with the power transmission coil, forms a power transmission-side resonance circuit; and a self-oscillation circuit that converts a DC voltage to an AC voltage, and that supplies the AC voltage to the power transmission coil. The wireless power transmission apparatus has a state, during power transmission, in which multiple resonance points exist in a combined resonance circuit formed by magnetic coupling of the power transmission-side resonance circuit with a power reception-side resonance circuit formed from a power reception coil and a power reception-side resonant capacitor. In the state, the self-oscillation circuit operates at the lowest frequency among the multiple resonance points.