13 



12 



II 



10 



9 



8 



7 



6 



5 



4 



3 



2 



I 



— Prorocentrum (golden - brown ) 



— — Dunoliellg (green) 

 -— Rhodosorus ( red ) 



--— Aphonothece (blue -green ) 



l\ 



S X S' 



\ 



J_ 



J I I L. 



360 



400 



440 



480 



520 560 



600 640 



680 



Wavelength , nm 



Figure 5.- Normalized excitation spectra for 

 representative algal species from four 

 algal color groups. Fluorescence emission 

 at 685 nm was detected while excitation 

 wavelength was changed. (Adapted from 

 ref. 8.) 



WATER /ALGAE MEDIUM 



\ 



FLUORESCENCE 



Figure 6.- Diagram used in derivation of equation for 

 power received by a laser fluorosensor system. 



34 



