Measuring Daylight Fluorescent Inks - Barbieri Spectro LFP qb Operating Manual

Spectro LFP qb - Operating Manual

4.9 Measuring daylight fluorescent inks

Fluorescent inks, as understood here and as used in the printing
industry, are inks which absorbe light in UV and visible wavelengths
and reradiates at longer wavelengths in the visible spectrum and is
manifested as color.
This effect occurs already under daylight condition.
The Spectro LFP qb is capable of illuminating in daylight condition by
using the M1 measuring condition and is therefore capable of stimulat-
ing this fluorescent effect.
The reradiated light is added to the normal reflected light resulting in
spectral curves which exceed the 100% remission.
The Spectro LFP qb is capable to automatically expand its dynamic range
when using the UpDown mode and is therefore capable of measuring
fluorescent inks which exceed by more than 200% the remitted light.
Therefore, to correctly measure fluorescent inks:
- use the M1 measurement condition
- use the UpDown measuring mode
- save spectral data into measuring files
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