Patent ID: 7369225

Claim:
A device for checking surfaces in the interior of holes or depressions, the device comprising: a light source for generating a light beam, the light beam being able to be focused by an imaging optic comprising a gradient index lens, the focused light beam being deflectable onto a surface using a deflection device; and a sensor device for detecting the light beam reflected from the surface, wherein a multicolor light beam is generated using the light source, which is focused by chromatic aberration of the imaging optic onto multiple points at various distances from the imaging optic, and the distance to the surface is able to be ascertained from the spectrum of the detected light beam, and wherein the gradient index lens is connected before additional optics such that a greater distance between the gradient index lens and the surface to be measured can be achieved, or a coupling of the light beams exiting from the gradient index lens into a light wave guide is possible.