ELECTRO-OPTICAL DEVICE AND METHOD FOR MONITORING INSTANTANEOUS SINGLET OXYGEN CONCENTRATION PRODUCED DURING PHOTORADIATION USING A CW EXCITATION SOURCE

摘要

A method and apparatus for optically monitoring the concentration of singlet oxygen produced during photoradiation. A composite optical emission in the 1.27 micron frequency band is detected and electrically processed to separate a first component due to the decay of singlet oxygen from a second unwanted component due to the fluorescence of the photosensitizing dye. A chopped CW excitation source (24, 26, 28) is used to excite the photosensitizing dye and a signal processing means (56) such as a lock-in amplifier (38) is used to separate the singlet oxygen emission component which appears out of phase from the chopped excitation signal and the in-phase photosensitizer fluorescence. The magnitude and/or other characteristics of the singled oxygen emission component can be used to determine properties of complex biological or other media. In a therapeutic environment the magnitude and/or other characteristics of the singlet oxygen emission can be used by the treating physician to set a therapeutic light dosimetry.