The use of optical elements fashioned from gelatin provides an engaging, low-cost way of performing a wide range of experiments relating to light and color. This article reviews some of the gelatin-based optical experiments described in the literature1–4 as well as introduces some novel approaches to using gelatin in the study of optics

Rectangular blocks, prisms, converging and diverging lenses, and light pipes can be fabricated from unflavored Knox® gelatin or agar-agar, an algae-based gelatin alternative. Flavored gelatins such as those from Jell-O® may be used to demonstrate selective absorption.

To prepare gelatin, simply follow the instructions on the product packaging. A more robust gel may be made by increasing the amount of gelatin prescribed in the recipe. After combining water and gelatin powder, place mixture in a flat container, such as a baking dish, then refrigerate. The gelatin should become firm after one to two hours of cooling....

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