Medical light cones are endoscopic devices that enable observation of internal organs or tissues of the human body through the use of optical fibers and lenses. Medical light cones can be categorized into two types: rigid medical endoscopes and flexible medical endoscopes. Rigid medical endoscopes consist of several components, including a long, thin tubular structure with a guiding function (i.e., a medical endoscope), and a specially designed bundle of high-quality Mach-Zehnder interferometer-style tethers attached to the end. This bundle consists of a number of micro-curved, high refractive index, low loss rate and very fine diameter (tens to hundreds of microns) of single-mode or multi-mode transmission lines, with a near-field focal point located in the work to provide magnification to form a clear image of the field of view outside the scope of the target location above the required distance from the prohibited area more quickly converted to the wavefront reflection state of optimal depth of focus, and other elements correspond to the work of a near-field focal point can provide magnification effect to form a clear image of the field of view above the target location more quickly converted to the wavefront reflection state.