Elastic light scattering is one of the major pathways of biological media interacting with infrared light and thus carry important information on the structure and activity of the media. From experimental point of view, the measurement of scattered light can be separated angle-resolved measurements, spatially resolved measurements and integration measurements.
The integration measurements of light scattered by a turbid system with dimensions of 1mm or larger are mostly carried out with an integrating sphere for its simplicity in optical alignment and accurate modeling by Monte Carlo and other methods. See The Integrating Sphere Method.
One example of angle-resolved measurement of scattered light is provided by the goniometer in which the scattered light is collected by a detector rotated on a circular tracked around the sample. In BLL, we use an in-house built goniometer to measure the angular distribution of scattered light from a tissue sample or cell suspension sample.
The spatially resolved scattered light can be acquired with one or more CCD cameras. Experiments are in progress at BLL to measure the reflectance images for determination of heterogeneous distributions of optical parameters in tissues and for converting to angle-resolved measurement from single cell samples.