Question

which phenomenon of light is used in endoscope in medical field​

Answer 1

An ophthalmoscope is an optical instrument for examining the interior of the eyeball and its back structures (called the fundus) through the pupil by injecting a light beam into the eye and looking at its back-reflection. An ophthalmoscope is also referred to as a funduscope.

Answer 2

Basically, a typical endoscope uses fiber optics, which allow for effective transmitting of light. In this technique (fiber optics) light is transmitted through a flexible fiber of glass (transparent) known as optical fiber(s).

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