The ceramicdischarge metal-halide (CDM) lamp, often referred to as Ceramic Metal Halidelamp (CMH) or Light Emitting Ceramic (LEC), is a source of light that is a typeof metal-halide lamp which is 10-20% more efficient than the traditional quartzmetal halide and produces a superior color rendition (80-96 CRI).

CDM lamps use onefifth of the power of comparable tungsten incandescent light bulbs for the samelight output (80–117 lm/W) and retain color stability better than most othergas discharge lamps. Like other high-intensity discharge lamps, they require correctlyrated electrical ballast in order to operate.

This relativelynew light source, touted for being compact, efficient, and powerful, is part ofthe high-intensity discharge (HID) lighting category, which offersthe highest efficacy and longest life of any lighting type, and saves upto 90% of lighting energy when they replace incandescent lamps.