Patent ID: 7215082

Claim:
An electrodeless self-ballasted fluorescent lamp, comprising: a luminous bulb in which a luminous gas is enclosed and which has a cavity portion; an induction coil inserted in the cavity portion; a ballast electrically connected to the induction coil; and a base electrically connected to the ballast, wherein the luminous bulb, the ballast and the base are configured as one unit, the luminous bulb includes an approximately spherical outer tube and an inner tube defining the cavity portion, the luminous bulb is made of glass, at least the surface of an upper hemisphere of the outer tube is coated with a silicone rubber having the property of transmitting light, the silicone rubber directly on the surface of the outer tube, and the following relationship is satisfied: −58.271 Ln ( T ave ·Res)+711.03<100 Ln represents a natural logarithm where Res is a resilience value [MPa·%] defined by multiplying 0.5 by a value equal to the tensile strength [MPa] of silicone rubber, and a value equal to the elongation at break [%] of silicone rubber, and T ave is an average film thickness [μm] of the silicone rubber; and wherein the silicone rubber is a silicone rubber in which an aromatic functional group has been introduced to absorb visible light in the blue range.