The invention provides a light indicator (100) for use in evaluating a quantity of melanopsin active radiation, the light indicator (100) comprising a light indicator element (110) comprising a sensing area (111), wherein the light indicator element (110) comprises a light reflecting element (120) configured to reflect at least part of light illuminating the sensing area (111) having one or more wavelengths selected from the wavelength range of an absorption band of melanopsin in the visible wavelength range and configured to absorb at least part of light illuminating the sensing area (111) having one or more wavelengths in the visible wavelength range outside the wavelength range of the absorption band of melanopsin in the visible wavelength range; and a non-sensing area (130) configured adjacent to the sensing area (111), wherein the non-sensing area (130) has an achromatic color having a lightness in the range corresponding to the lightness of shades of gray.