Tire checking device

A holographic checking device for observing both bead zones as well as inner wall surfaces of tires of land and air vehicles free of any destruction thereof using the same optical arrangement with two different adjustments thereof which includes a coherent light source, a photo shutter, as well as an optical circuit dividing a beam emitted by the light source into an object beam and into a reference beam and which deflects these beams by an optic circuit, and which also includes a conical mirror coaxial with the tire to be checked and located in the path of said object beam coinciding therewith while a registering layer is located in the beam cone of the object beam reflected in a diffused manner by the tire surface to be checked through the intervention of said conical mirror, said device also including an observing system adapted to observe said registering layer, means for subjecting the tire to be checked to a pressure drop relative to the atmosphere surrounding the tire to be checked, means for changing height position of the tire relative to said conical mirror including a removable holding device and a hood as well as a platform arranging said conical mirror on said removable holding device at a height differing from the height of the tire to be checked when the latter occupies its lying position while said holding device embraces the tire to be checked, said holding device for the conical mirror being movably connected to said hood which surrounds the last mentioned holding device and extends over the platform while forming an airtight closing member adapted to be evacuated and to be lifted and lowered, the tires to be checked being arranged on devices adapted to be placed upon the platform coaxially about the conical mirror for observing the inner side of the tire tread surface and being arranged coaxially below said conical mirror for observing both the bead zones and inner wall surfaces at differing heights.