Konjac glucomannan sol was made into film with light conversion agent Eu4PMA3,fluorescence spectra and dependence of intensity on thickness of the sample film were investigated.Results showed that the thickness of the sample film should be more than 0.52 mm when the intensity of the film was measured,and the fluorescent properties of the film was as the same as the one of light conversion agent,which absorbed ultraviolet and emit red light(620 nm),light conversion behavior had benefits to photosynthesis of ...