Abstract: A constant voltage power supply circuit includes oscillation means; a step-up or step-down circuit including coil means and capacitive means; detecting means that detects an outputted voltage value of the step-up or step-down circuit, and compares the detected value with a predetermined reference value to output a detected information, at which either the detected value exceeds the reference value or becomes lower than the reference value; and control means that controls, based on the detected information of the detecting means, supply of the pulse signals outputted from the oscillation means to the step-up or step-down circuit.

Abstract: A lighting apparatus that can operate longer utilizing a battery is provided. A lighting apparatus comprises a battery, switch means, at least two types of light sources, the power consumption of each being different from each other, capable of being connected to the battery via the switch means, voltage detection means for detecting a voltage of the battery, and switch control means for controlling the switch means to switch the connection target of the battery between the at least two types of light sources in response to the output signal of the voltage detection means.

Abstract: Two types of rectangular waves having different numbers of driving pulses are applied to the HID bulb. By changing the combination of these two different types of rectangular waves to be supplied , the driving energy of the HID bulb is increased or decreased, thereby supply electric energy to the HID bulb is controlled accurately.

Abstract: There is a vehicle headlamp in a multibeam mode comprising: a reflecting mirror for reflecting light emitted from a discharge tube having a single light emitting section; and a shield for blocking off light directly emitted forward and light emitted to the lower part of the reflecting mirror out of the light emitted from the discharge tube, wherein the headlamp includes a rotationally moving device for three-dimensionally moving the light emitting section of the discharge tube to any position of the reflecting mirror, which is suitable for low-beam or high-beam, by eccentrically rotating the discharge tube to move back and forth; and a rotation controller for controlling the rotation of the rotationally moving device. The headlamp can be used in several beam modes using a conventional reflection mirror and a discharge tube.