Candlepower
From Memory Alpha, the free Star Trek reference.
Candlepower, candlelight, or simply candles is a measure of light intensity. Galaxy-class starship computers could set the light level of a room to a specific candlepower. (TNG: "Galaxy's Child")
Spock calculated that one million candles per square inch was required to kill the neural parasite encountered on Deneva. (TOS: "Operation -- Annihilate!")
