A boroscope has a first end and a second end and the first end of the boroscope has an optical fiber, a light source, a lens, a beam expander and a transmissive diffractive optical element. The optical fiber extends from the first end of the boroscope to the second end of the boroscope. A laser optical fiber extends from the lens at the first end of the boroscope to the second end of the boroscope and a laser source is arranged to direct a laser beam into the laser optical fiber. The beam expander is provided between the laser optical fiber and the lens and the lens is provided between the beam expander and the transmissive diffractive optical element. The transmissive diffractive optical element is arranged to produce a laser beam with a predetermined shape and a focal length probe extends from the first end of the boroscope.