| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device having several LED elements arranged in an annular manner so as to perform an efficient heat radiation, restrict occurrence of speckled light in brightness and capable of assuring a prescribed brightness, and provide a light source substrate that is preferably used in the lighting device having LED elements arranged in an annular manner.SOLUTION: There are provided a light source substrate 10 in which a long band-like substrate is curved and formed in a substantial annular shape, several LED (light emitting diode) elements 8 arranged at the light source substrate and electric supply means 30 electrically connected to the light source substrate for supplying electricity to the LED elements. Several corrugated protrusions 10d are arranged along a peripheral direction below the light source substrate, each of the protrusions is curved or folded in several steps toward a diametral direction in a different direction so as to form several substrates surfaces 10e, 10f facing in different directions and the LED elements are arranged at several substrates facing in the different directions. |
