Open AccessFluorescence spectrum estimation using multiple color images and minimum negativity constraint
Author(s) -
Maricor Soriano,
Wilma Oblefias,
Caesar Saloma
Publication year - 2002
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.10.001458
Subject(s) - optics , dichroic glass , spectrometer , materials science , pixel , fluorescence , microscopy , microscope , spectral imaging , color filter array , physics , color gel , layer (electronics) , composite material , thin film transistor
An inexpensive method to convert a microscope into an imaging spectrometer is presented. Unlike current microscope-based spectrometers which use specialized optics or scanning mechanisms, our system only requires at most two image captures with a 3-chip CCD camera and a lightly-tinted color filter to output the color signal of a sample at each pixel. Basis spectra are obtained by principal components analysis applied to an ensemble of color signals of commercially-available dyes observed with different dichroic mirrors. A transformation matrix from channel values to spectral coefficients is derived. Minimum negativity constraint is applied to eliminate negative parts of the reconstructed fluorescence spectrum. The technique is demonstrated on fluorescence microspheres (fluorospheres) and chlorophyll from plant leaf.