High Resolution Optical Coherence Tomography (OCT) System For Integration With A Multimodal Optical Imaging Workstation

Development and construction of a high resolution Optical Coherence Tomography (OCT) system is described. OCT is one of the modalities in an integrated multimode optical imaging workstation built around an inverted Differential Interference Contrast (DIC) microscope in our laboratory, to image cells and tissue samples. The design and construction of the OCT sample path is dictated by its integration to the optical imaging workstation. The OCT system is controlled via a DAC card, interfaced using LabVIEW to the computer. The image of the sample under observation is constructed from the raster scan data acquired by the DAQ. Ti-Sapphire broadband laser source provides the input to the interferometer. OCT resolution being highly dependent on the bandwidth of the source, the effect of bandwidth on depth resolution is experimentally evaluated and it is seen that the depth resolution increases with increase in bandwidth. Sample path for enface scan and reference path for depth scan is calibrated and tested. Dispersion compensation is performed. SNR for the system is experimentally measured to be 61dB. Experiments showing high resolution imaging capability with variety of samples are demonstrated.