Hydrargyrum quartz iodide
(重定向自HQI)
Hydrargyrum quartz iodide (HQI) is a special type of high-intensity discharge (or HID) lighting, where the light is produced by an electrical arc through a gas. Hydrargyrum is the Latin name for the element mercury. When heated, mercury vapour is created inside the lamp, and deposited when it cools.