Opaque Projectors

Define An Opaque Projector

Opaque projectors are the forerunners of overhead projectors. They are used to display images from opaque sheets, such as printed materials from books, art, or drawings, and are also commonly referred to as episcopes and epidiascopes.

How To Build An Opaque Projector

Due to the simplistic nature of opaque projectors, some enthusiasts find that building their own is a doable undertaking. Plans to build one can be easily located through a quick online search, or they can be purchased through online auctions. The basic components to an opaque projector consist of a box, which can be made from ply wood, used as the outer casing and body of the apparatus, a lens, a mirror for refraction, and a good source of lighting. With some fundamental skills, and the ability to follow directions, you can put together a fully functioning opaque projector to use at home. First, determine what type of projector you would like to make, for this example I will use a table top projector, and begin with the outer shell. Construction of the shell is pretty basic, almost a complete box, but with an angled side as placement for the mirror. The bottom of the projector should have an open space for placement of the copy with the light source located directly above. The mirror in turn would be angled above the light source to reflect the image through the lens, which is mounted through a hole directly across from the mirror to project the image outwards. Strength and quality of the image will depend upon the type of lens and lighting used.

Bulbs For Opaque Projectors

Opaque projectors, especially those built at home, are able to use various kinds of bulbs. Although there may be several options for bulb use, what matters here is not so much the type of bulb that is put to use as it is more the wattage. Image quality and projection power is subject to the intensity of lighting. Typically, 1000 watt bulbs are utilized in most purchased projectors. There are several different kinds of bulbs that are suited for opaque projectors such as halogen, fluorescent, and filament. Fluorescent bulbs are sometimes favored due to the intensity of light produced without generating a great deal of heat.