# Power Density

The term power density is sometimes used as a short form of Power Spectral Density in the context of Noise specifications. It also occurs with the meaning of an Optical Power spectral density. In other cases, it is meant to be an optical power per unit area, but optical Intensity is then a more appropriate term. In order to avoid such confusion, it is recommended to avoid the use of this term altogether, unless the context makes clear which meaning is used.