| 摘要 |
PROBLEM TO BE SOLVED: To guarantee the precise centering of a luminous body by applying the constitution that a point-like limiting part is formed out of three projections, and each projection is formed to have a funnel type node with a bulb wall, so as to be orthogonal with the luminous body at equal intervals. SOLUTION: Three systems 11 for a node 12 are arranged as a whole approximately at equal intervals along the axial direction of a bulb 2, and holds a luminous body 5 like a point support. As a result, each luminous part 6 is not slackened and properly arranged along a center within four cylindrical bulb segments 13. In this case, the bulb segments 13 are separated from each other via each system 11. According to this construction, a halogen cycle is not hindered by the systems 11, and the optical characteristic of the bulb 2 is evenly maintained. Also, each system 11 is made of three nodes 12 on a plane orthogonal with a bulb axial line. The nodes 12 are formed to have a funnel shape, and radially directed inside toward the luminous body from a bulb wall at mutual angular intervals of 120 degrees. Also, the nodes 12 have a circular funnel shape. |
