One of the specialty types of magnetic compasses, the prismatic compass makes use of a small capsule that is filled with oil and a magnetized dial. This combination is augmented with a battery powered illumination component that helps to provide one of the most accurate compass readings of any type. Sometimes referred to as an optical compass, the pinpoint accuracy of the device helps to make prismatic compasses ideal for a number of applications where lighting is in limited supply.

As with all types of compasses, the prismatic compass makes it easy to isolate a direction from any point on the planet. The pointer within the device will align with the pull of the natural magnetic field of the earth, ensuring that the compass will make it easy to accurately determine the basic directions of north, south, east, and west. It is not unusual for the magnetic compass to be used as part of an overall navigation process, with such devices as chronometers and sextants used to further refine the process of plotting a course.

The prismatic compass, due to its luminescent qualities, makes the device ideal for use in any environment where visibility is somewhat limited. When navigating through an underground system such as a cave, a prismatic compass will provide a reliable means of reading direction, helping to prevent the explorer from becoming lost. Applications within the professions that depend on surveying land and other property also often make use of the prismatic compass.

Perhaps one of the most common uses of the prismatic compass is with any task or profession that involves waterways or the ocean. Marine biologists can make use of the compass when conducting underwater explorations, making it easy to record directions to and from a starting point. The prismatic compass can be especially helpful in deeper waters, where there is very little in the way of light.

Generally, the prismatic compass is designed to handle heavy-duty use, and is both air and watertight. Many models of the prismatic compass can be mounted on a tripod when appropriate, as well as held and operated in one hand. With a long battery life, it is possible to rely upon the prismatic compass for long periods of time before a charge is required.