Research On Optical Coherence Tomography Probe

Optical coherence tomography(OCT)is an imaging technique that performs high-resolution,cross-sectional tomographical images of the internal microstructure in materials and biological systems.It has been rapidly developed in the past two decades.This article designed an OCT probe with less radiation based on the fact that traditional endoscope can only detect the surface of internal organs.The probe was made and its working distance is 1.47 mm and the transversal resolution is 25?m,while do no electromagnetic harm to human beings.The main work is followed as below:1.Acquired the principle of Optical Coherence Tomography as well as introduced the composition of an OCT system,its classification and key parameters.Deduced the longitudinal resolution and transversal resolution,and analyzed the factors that effect on the imaging time and the depth of focus.2.Design the probe and set its specifications as below: Probe outside diameter not larger than 2mm;Designed for a central wavelength of 1310nm;No electrical signals must enter the human body;Probe body length between 1m and 1.4m;Transversal resolution smaller than 30?m;The probe can be connected to the OCT system through a rotating connection.3.Optical design and mechanical design of the probe.Completed the optical element selection and determined the parameters of GRIN lens.By the application of metal tube and spring structure,improving the working stability of the probe.Light and mechanical simulation were completed.The motor can drive the probe for line and rotational movement.4.Set up the OCT system.Couples of collimators and an optical delay line were made for focusing the light spot and matching the optical path.5.Preliminarily accomplished the assembly of the probe.The probe was tested.The working distance is 1.47 mm and the transversal resolution is 25?m,which satisfying the design requirements very well.