Hawkeye® Blue Swing Prism Borescopes
have a tiny prism at the tip that pivots, or “swings,” to vary the direction-of-view from 16° to 118°. A ring on the borescope body controls the prism direction. The field of view is 45°, so the borescope effectively sees from -7° to 133°.
Another ring focuses the borescope, and a third rotates the borescope tube over more than 360°, sideways in any direction, without turning the body.
Diesel engine mechanics use Swing Prism Borescopes to examine cylinders, pistons, and valves. Aircraft engine
mechanics use the Swing Prism to locate and investigate FOD (foreign object damage and debris) in jet engines.