Patent ID: 8164047

Claim:
An illuminance device, comprising: a gas discharge lamp having a reflector, a base connected to the reflector, a burner installed in the reflector and the base, a first opening, and a second opening, wherein the first opening is located at the reflector and a front part of the gas discharge lamp, and the second opening is located at a rear part of the gas discharge lamp and exposes the burner; a first airflow generator capable of providing a cooling airflow; and a distributing duct having an inlet, a first outlet, and a second outlet, wherein an opening area of the first outlet is larger than an opening area of the second outlet, the cooling airflow provided by the first airflow generator is capable of entering the distributing duct via the inlet, the distributing duct is capable of guiding a part of the cooling airflow to the first opening for entering the reflector via the first outlet, and the distributing duct is capable of guiding another part of the cooling airflow to the second opening via the second outlet for cooling the burner.