OCT, also called optical coherence tomography, is a diagnostic imaging device that provides a cross-sectional image of the retina through optical principles for objective quantitative measurements and qualitative clinical analysis in the detection of glaucoma and retinal disease. OCT imaging uses the latest high-resolution scanning technology to analyze retinal thickness, retinal nerve fiber layer, and optic disc in three dimensions, making it the only meter that provides all three diagnostic functions. oCT presents us with dynamic information about the retina that has never been seen before, and OCT is different from the existing The OCT is a tomographic imaging device that is different from the general tomographic units that are already available.