What is a Fiber-Optic Borescope?

A fiber-optic borescope is a borescope that utilizes fiber-optics for its transmission medium. This optical device is used to visually inspect areas that are not easy to access. Fiber-optic borescopes are used primarily in the medical field to examine the inside of the human body and because they utilize fiber-optic cables, they are flexible and won’t damage skin or tissue.

Borescopes are typically are made up of a flexible or rigid tube that has an eyepiece on one end and an objective lens, the part that gathers light and also focuses the image, on the other. These two pieces are connected by some type of optical relay system. In the case of a fiber-optic borescope, fiber-optic cables serve as the connector. The image transmitted is first formed by the objective lens, then passes through the relay medium, and the eyepiece receives the image on the other end and magnifies it for the viewer.

There are two primary classifications of borescope: flexible and rigid. A rigid borescope is stiff and not bendable, and is advantageous because it creates a clearer image than flexible borescopes, due to less pixilation and pixel crosstalk. The disadvantage for the rigid borescope is that it cannot bend. A flexible borescope, also known as a fiberscope, can bend and move into spaces that aren't directly accessible, but the image it creates is generally not as clear as a rigid borescope. Fiber-optic borescopes usually fall under the flexible category.

Borescopes are usually used by people who need to get into spaces to inspect them. Engine builders of all kinds use them, especially where safety is of utmost concerned such as in the building of airplane engines, as do people who repair computers. Exterminators use borescopes to inspect behind walls or under a building. The primary use for a fiber-optic borescope is in the medical field. It is used to look into body cavities and is referred to as an endoscope. Some fiber-optic borescopes, because it utilizes fiber-optic cables, can be used to see images very long distances, although the longest created are usually only several hundred feet.

There are several factors that go into determining a good quality fiber-optic borescope. Flexibility, quality of the image, and viewable area are all important factors. The quality of the view will be measured by the number of pixels used when creating the image. A minimum of 10,000 pixels is desirable, but higher rated fiber-optic borescopes can go above 20,000. The borescope should be able to bend in a variety of ways, and the viewable area should be large enough to view what it is that needs to be viewed.