CIE S 010/E Photometry-the CIE System of Physical Photometry

The visual brightness of a light source depends not only on the amount of radiation it emits
but also on its spectral composition and on the visual response function of the observer
viewing it. Because human visual response varies at different light levels and from person to
person, precise photometry requires the definition of representative standard observers. The CIE system of physical photometry specifies procedures for the quantitative evaluation of
optical radiation in terms of the spectral luminous efficiency functions of two such standard
observers. One, V(λ), represents photopic vision and the other, V(λ), scotopic vision. Used in
conjunction with the SI photometric base unit, the candela, these functions constitute a
system that enables the values of photometric quantities for all types of luminous source to be
precisely determined, regardless of the spectral composition of the radiation emitted.

LISUN following instruments fully meet CIE S 010/E Photometry-the CIE System of Physical Photometry:

LPCE-2(LMS-9000) High Precision Spectroradiometer Integrating Sphere System

LPCE-3 CCD Spectroradiometer Integrating Sphere Compact System