Patent ID: 6374128
Filing Date: 2002-04-16
Classification: A61B

Abstract:
A blood vessel imaging system comprisinga measuring light source which emits a measuring light beam, a scanning means which causes the measuring light beam to scan an organism, an optical heterodyne detection system consisting of an optical system which splits the measuring light beam upstream of the organism into a first light beam traveling to impinge upon the organism and a second light beam traveling not to impinge upon the organism and combines the second light beam with the first beam emanating from the organism into a combined light beam, a frequency shifter which causes the first and second light beams to have frequencies different from each other, and a beat component detecting means which detects beat components of the combined light beam, a filtering means which detects, out of the beat component detection signal output from the beat component detecting means, off-centered components in a frequency band deviated from the center frequency of the beat component detection signal by a predetermined width, and an image signal generating means which generates an image signal according to whether the off-centered beat signal detected by the filtering means is higher or lower than a predetermined threshold level.