It is the study of the interaction between matter and radiated energy. Spectroscopic data is often represented by a spectrum, a plot of the response of interest as a function of wavelength or frequency. The spectroscopy is a very useful technique to identify unknown materials.
FTIR : (Frontier, Perkin Elmer) Helps to identify the polymer through the detection of functional groups present in its back bone
Colour Matching Spectra photometer (BGD556, Aadarsh-Bieuged): Colour matching spectrophotometer is basically used to determine the value of DE, DC, DH, L, A, B and C, for all Polymer, paints and liquids in both SCI and SCE mode.
This machine also measures yellowness and whiteness index for polymers, and powders.
It is very much useful to check the colour consistency from batch-to-batch.