The optical system in some instances is surrounded by optical fibres used for illumination of the remote object. An internal image of the illuminated object is formed by the objective lens and magnified by the eyepiece in order to presents it to the viewer's eye.
A video borescope or "inspection camera" is similar to the flexible borescope but uses a miniature video camera at the end of the flexible tube. The end of the insertion tube includes a light which makes it possible to capture video or still images deep within equipment, engines and other dark spaces.
As a tool for remote visual inspection the ability to capture video or still images for later inspection is a huge benefit. A display in the handle shows the camera view, and the viewing position can be changed via a joystick control or similar controls.
Because the complex optical wave guide is replaced with an inexpensive electrical cable, video borescopes can be much less costly and potentially better resolution (depending on the specifications of the camera).
Configuration of a Borescope
Borescopes are used for visual inspection work where the area to be inspected is inaccessible by other means. Borescopes are mostly used in NDT techniques for recognizing defects or imperfections. Borescopes are commonly used in the following application:
- Visual inspection of aircraft engines
- Industrial gas turbines
- Steam turbines
- Diesel engines
- Automotive and truck engines