Abstract: Provided is a lighting unit and a discharge lamp each of which is capable of causing a capacitor to break down by heat generated in a heat generating component, so that circuit operation is safely terminated without any additional cost. A compact self-ballasted fluorescent lamp is provided with a lighting unit (50) housed in a case. The lighting unit (50) causes an arc tube to emit light and is composed of a plurality of electronic components, including a rectifier/smoothing circuit portion, an inverter circuit portion having transistors (Q1 and Q2), a resonant circuit portion, and a preheating circuit portion having a positive temperature coefficient element. Among the plurality of electronic components, the transistors (Q1 and Q2) and the positive temperature coefficient element generate excessive heat when, for example, the lamp is operated at the end of electrode's life.

Abstract: Provided is a lighting unit and a discharge lamp each of which is capable of causing a capacitor to break down by heat generated in a heat generating component, so that circuit operation is safely terminated without any additional cost. A compact self-ballasted fluorescent lamp is provided with a lighting unit (50) housed in a case. The lighting unit (50) causes an arc tube to emit light and is composed of a plurality of electronic components, including a rectifier/smoothing circuit portion, an inverter circuit portion having transistors (Q1 and Q2), a resonant circuit portion, and a preheating circuit portion having a positive temperature coefficient element. Among the plurality of electronic components, the transistors (Q1 and Q2) and the positive temperature coefficient element generate excessive heat when, for example, the lamp is operated at the end of electrode's life.

Abstract: Provided is a lighting unit and a discharge lamp each of which is capable of causing a capacitor to break down by heat generated in a heat generating component, so that circuit operation is safely terminated without any additional cost. A compact self-ballasted fluorescent lamp is provided with a lighting unit (50) housed in a case. The lighting unit (50) causes an arc tube to emit light and is composed of a plurality of electronic components, including a rectifier/smoothing circuit portion, an inverter circuit portion having transistors (Q1 and Q2), a resonant circuit portion, and a preheating circuit portion having a positive temperature coefficient element. Among the plurality of electronic components, the transistors (Q1 and Q2) and the positive temperature coefficient element generate excessive heat when, for example, the lamp is operated at the end of electrode's life.

Abstract: Discoloration and deformation of a resin case triggered by heat generation from a failed circuit component at the end of the life of an arc tube are prevented without increasing the cost and size. A lighting unit that lights a light source with an inverter while receiving electric power from an AC power supply, and that contains a lighting circuit that includes a plurality of circuit components inclusive of capacitors. Among the capacitors, all capacitors with an applied voltage of 50V or greater (C4, C5, C6, C7, C8, CD1 and CD2) are foil type film capacitors with exceptions of smoothing electrolytic capacitors (CD1 and CD2).

Abstract: Discoloration and deformation of a resin case triggered by heat generation from a failed circuit component at the end of the life of an arc tube are prevented without increasing the cost and size. A lighting unit that lights a light source with an inverter while receiving electric power from an AC power supply, and that contains a lighting circuit that includes a plurality of circuit components inclusive of capacitors. Among the capacitors, all capacitors with an applied voltage of 50V or greater (C4, C5, C6, C7, C8, CD1 and CD2) are foil type film capacitors with exceptions of smoothing electrolytic capacitors (CD1 and CD2).

Abstract: Provided is a lighting unit and a discharge lamp each of which is capable of causing a capacitor to break down by heat generated in a heat generating component, so that circuit operation is safely terminated without any additional cost. A compact self-ballasted fluorescent lamp is provided with a lighting unit (50) housed in a case. The lighting unit (50) causes an arc tube to emit light and is composed of a plurality of electronic components, including a rectifier/smoothing circuit portion, an inverter circuit portion having transistors (Q1 and Q2), a resonant circuit portion, and a preheating circuit portion having a positive temperature coefficient element. Among the plurality of electronic components, the transistors (Q1 and Q2) and the positive temperature coefficient element generate excessive heat when, for example, the lamp is operated at the end of electrode's life.

Abstract: A base substrate of a printed wiring board is coated, by wet plating, with metal films over two major surfaces thereof and the inner walls of through-holes formed therein wherein the metal films formed over the inner walls of the through-holes form via-holes for electrically connecting the metal films formed over the two surfaces with each other. In the wet plating, the base substrate is taken out of the plating bath for a first predetermined period of time, to thereby cause disintegration of bubbles on the surfaces of the base substrate and the inner walls of the through-holes therein. Then, the base substrate is again immersed into the plating bath for a second predetermined period of time to resume the formation of the metal films.