Abstract
Two versions of the Laser Speckle Flowgraphy system are presented - one version visualizes the microcirculation map of skin tissue and the other version analyzes the blood flow distribution of smaller tissue areas, such as the human retina. For the larger target tissue, the area is illuminated by the laser line spot, which is scanned across the tissue and the spot is imaged onto the line sensor. The signal is transmitted to a PC and the blood flow map is calculated from the difference of two successive scans for the regions of 60×60mm in a few seconds with 200×200 resolution. Similarly, the retina is illuminated with a diode laser spot through a retinal camera and the speckle field at the image plane of the spot is scanned by a CCD camera. More than 100 frames of the speckle image are captured by a PC and the square blur rate of the intensity variation at each pixel point is evaluated.. The results are displayed successively on 2-D color maps which allows real-time observation of retinal blood flow. Various applications of these versions are also demonstrated.
