METHOD AND APPARATUS FOR DETERMINING ABSORPTION OF ELECTROMAGNETIC RADIATION BY A MATERIAL

摘要

A method of determining a portion of light at a given wavelength which is incident on a material that is absorbed by the material, the method comprising: transmitting a pulse of light at the given wavelength so that the pulse traverses a path through the material; generating a first signal responsive to light in the light pulse that traverses the path length without being absorbed by the material; generating a second signal responsive to energy that the material emits responsive to a portion of the light from the light pulse that is absorbed by the material as the light pulse traverses the path; and using the first and second signals to determine the absorbed portion.