Proposal of Edible Retroreflector and Its Prototype

Abstract

Retroreflectors can reflect incident light to the light source, and they are often used as the optical marker for machine vision. Most of the conventional retroreflectors are made from glass or plastic, and they are not edible. Thus, it is difficult to apply them to foods or inner wall of digestive organs. This paper proposes edible retroreflector made from foodstuffs. A recipe of the edible retroreflector using kanten, which is traditional Japanese cooking ingredient to form a transparent jelly, is described. A prototype made from kanten showed retroreflective function from reflectance measurement experiment. Dynamic projection mapping on a Swiss roll was successfully demonstrated using the prototype as an optical marker.