Circular fluorescent lamp unit and lighting apparatus

DETAILED DESCRIPTION It is, therefore, an object of the present invention to provide a fluorescent lamp unit which has the higher light flux and higher efficiency than those of a conventional down light unit such as a compact fluorescent lamp unit or a krypton lamp unit and can be attached in a narrower space, and a lighting apparatus using this fluorescent lamp unit.
In a circular fluorescent lamp unit according to the present invention, a glass bulb is bent in the ring form with both ends abutting on each other.
The inner wall of the glass bulb is coated with phosphor powder, and electrodes are provided at respective ends in an inner space thereof.
Mercury and inert gas are sealed within the glass bulb, and a cap which has a connection pin used for electrically connecting the electrodes in the glass bulb to the outside is attached so as to cut across the both ends of the glass bulb.
A tube outer diameter of the glass bulb has a range of 13 mm to 20 mm and a ring outer diameter of the ring has a range of 145 mm to 170 mm.
Additionally, according to the present invention, there is provided a lighting apparatus, which uses the above-described circular fluorescent lamp.