noun
light intensity; illuminating power
Technical term used in physics and engineering to refer to the strength or illuminating power of light.
この光源の光力は非常に高い。
The light intensity of this light source is very high.
光力を測定する装置を開発した。
We developed a device to measure illuminating power.
Compound of 光 (light) and 力 (power, strength). The exact historical derivation is uncertain, but the term is used in technical contexts to denote the power or intensity of light.