Patent ID: 7825599

Claim:
A lighting control apparatus of a vehicle-purpose lighting device comprising: light amount instruction value setting means to which information related to either a status of a vehicle or a lighting operation of a light source is inputted, the light amount instruction value setting means setting a light amount instruction value based on said information; and electric power supplying means for supplying an input voltage from a power supply to a lower beam-purpose semiconductor light source in accordance with said light amount instruction value, wherein: when information for indicating that a vehicle speed is lower than a predetermined speed value is inputted to said light amount instruction value setting means, said light amount instruction value setting means sets a light amount instruction value by which said lower beam-purpose semiconductor light source is lighted under beam-attenuating condition up to a light emitting degree capable of satisfying a predetermined luminous intensity distribution; and when information for indicating that an upper beam-purpose light source is lighted is inputted to said light amount instruction value setting means, said light amount instruction value setting means sets a light amount instruction value such that a light emitting degree is lowered from that of said beam-attenuating lighting operation so as to light said lower beam-purpose semiconductor light source under beam-attenuating condition; said light amount instruction value setting means includes a temperature detecting element for detecting an ambient temperature; and when a temperature detected by said temperature detecting element reaches a predetermined temperature, said light amount instruction value setting means sets a light amount instruction value used to decrease the temperature of said lower beam-purpose semiconductor light source lower than, or equal to, a setting temperature, or sets a light amount instruction value used to restrict the temperature of said lower beam-purpose semiconductor light source to said setting temperature, which correspond to light amount instruction values used to reduce a light emitting degree of said lower beam-purpose semiconductor light source, and outputs any one of said set light amount instruction values to said electric power supplying means.