Patent ID: 7042158

Claim:
A self-ballasted fluorescent lamp comprising: an arc tube formed by parallely arranging a plurality of U-shaped bent bulbs in such a manner that the maximum width of the bulbs ranges from about 32 mm to about 42 mm, each of which has a bent portion and straight portions; a distance w 1 between the two straight portions of each U-shaped bent bulb being so set as to be nearly identical to a distance w 2 between each straight portion of each U-shaped bent bulb that is adjacent to said straight portion; said distances w 1 , w 2 being respectively limited in the range from about 1 mm to about 5 mm; a cover including a base that is adapted to permit said arc tube to be attached thereto; a lighting circuit which includes a circuit board having the maximum width ranging up to 1.2 times the maximum width of the arc tube, said maximum width of the arc tube being the dimension along which the U-shaped bent bulbs are arranged; and said lighting circuit contained in the cover in such a manner that the circuit board is positioned with one of its sides facing all the ends of the straight portions of the arc tube.