Abstract: There is provided a discharge lamp controlling apparatus mounted on vehicles or others. The apparatus includes a discharge lamp, a power control section, a signal inputting section, and a storage which are united with each other. The signal inputting section allows a power command signal to be inputted from the outside of the apparatus, the power command signal being for commanding the value of power supplied to the discharge lamp, and extracts from the inputted power command signal commanded power values which command the value of the power. The storage section stores therein, at least, the newest commanded power value among the extracted commanded power values. The power control section controls the power supplied to the discharge lamp based on the newest command values stored in the storage section.

Abstract: A discharge lamp unit has a supporting part for supporting a discharge lamp, and circuit elements from which electric power is supplied to the discharge lamp through electric wires. The electric wires have radiation parts. In order to increase an amount of heat energy radiated and discharged from the radiation parts, each of the radiation parts has a large surface area when compared with that of parts other than the radiation parts in the electric wires. The structure of the electric wires makes it possible to decrease heat energy conducted from the discharge lamp side toward the circuit elements.

Abstract: A discharge lamp unit has a supporting member supporting a discharge lamp, a circuit substrate supplying electric power to the discharge lamp, a housing case member, a separation wall, and a hollow part. The housing case member supports the circuit substrate in an inside space thereof and the supporting member. The supporting member is exposed to an outside of the housing case member. The separation wall separates the supporting member from the circuit substrate in the inside space of the housing case member. The hollow part is formed between the separation wall and the circuit substrate. When the supporting member is heated by heat energy of the discharge lamp, the separation wall shields the heat conduction from the supporting member to the circuit substrate. The presence of the hollow part between the separation wall and the circuit substrate prevents heat conduction from the discharge lamp side to the circuit substrate.

Abstract: In a discharge lamp unit, a casing member arranged such that the casing member holds a circuit board therein and holds a discharge lamp supporting section being exposed outside of the casing member. A thermal absorption protect layer is formed on the surface on the side on which the discharge lamp supporting section is exposed. The thermal absorption protect layer allows the casing member to inhibit absorption of radiant heat induced by the discharge lamp. Since the thermal absorption protect layer inhibits the casing member from absorbing the radiant heat from the discharge lamp, the amount of heat generated by the discharge lamp reaching the circuit board may be reduced. Therefore, the circuit board is not easily heated.

Abstract: A discharge lamp unit constitutes circuit components including self-heating components that radiate the heat, i.e., a circuit board and a DC/DC transformer, and a heat radiation member. The heat radiation member made of metal is arranged in a portion between the self-heating components and the other components, so as to cover at least a portion of the self-heating component. In the discharge lamp unit, the heat produced by the self-heating components can be absorbed by the heat radiation member before the conducting heat reaches the circuit components other than the self-heat components. As a result, the heat produced by the self-heating components can be effectively radiated away.

Abstract: There is provided a discharge lamp controlling apparatus mounted on vehicles or others. The apparatus includes a discharge lamp, a power control section, a signal inputting section, and a storage which are united with each other. The signal inputting section allows a power command signal to be inputted from the outside of the apparatus, the power command signal being for commanding the value of power supplied to the discharge lamp, and extracts from the inputted power command signal commanded power values which command the value of the power. The storage section stores therein, at least, the newest commanded power value among the extracted commanded power values. The power control section controls the power supplied to the discharge lamp based on the newest command values stored in the storage section.

Abstract: A discharge lamp unit constitutes circuit components including self-heating components that radiate the heat, i.e., a circuit board and a DC/DC transformer, and a heat radiation member. The heat radiation member made of metal is arranged in a portion between the self-heating components and the other components, so as to cover at least a portion of the heat radiation member. In the discharge lamp unit, the heat produced by the self-heating components can be absorbed by the heat radiation member before the conducting heat reaches the circuit components other than the self-heat components. As a result, the heat produced by the self-heating components can be effectively radiated away.

Abstract: In a discharge lamp unit, a casing member arranged such that the casing member holds a circuit board therein and holds a discharge lamp supporting section being exposed outside of the casing member. A thermal absorption protect layer is formed on the surface on the side on which the discharge lamp supporting section is exposed. The thermal absorption protect layer allows the casing member to inhibit absorption of radiant heat induced by the discharge lamp. Since the thermal absorption protect layer inhibits the casing member from absorbing the radiant heat from the discharge lamp, the amount of heat generated by the discharge lamp reaching the circuit board may be reduced. Therefore, the circuit board is not easily heated.

Abstract: A discharge lamp unit has a supporting part for supporting a discharge lamp, and circuit elements from which electric power is supplied to the discharge lamp through electric wires. The electric wires have radiation parts. In order to increase an amount of heat energy radiated and discharged from the radiation parts, each of the radiation parts has a large surface area when compared with that of parts other than the radiation parts in the electric wires. The structure of the electric wires makes it possible to decrease heat energy conducted from the discharge lamp side toward the circuit elements.

Abstract: A discharge lamp unit has a supporting member supporting a discharge lamp, a circuit substrate supplying electric power to the discharge lamp, a housing case member, a separation wall, and a hollow part. The housing case member supports the circuit substrate in an inside space thereof and the supporting member. The supporting member is exposed to an outside of the housing case member. The separation wall separates the supporting member from the circuit substrate in the inside space of the housing case member. The hollow part is formed between the separation wall and the circuit substrate. When the supporting member is heated by heat energy of the discharge lamp, the separation wall shields the heat conduction from the supporting member to the circuit substrate. The presence of the hollow part between the separation wall and the circuit substrate prevents heat conduction from the discharge lamp side to the circuit substrate.