METHOD AND APPARATUS FOR MEASURING THE INTERIOR DIMENSIONS OF A HOLLOW BODY

摘要

An apparatus for measuring the interior dimensions of the walls of a hollow body. The apparatus is insertable into a restricted opening of the hollow body and includes means for transmitting a beam of electromagnetic energy toward an interior wall of the hollow body. When the electromagnetic energy illuminates the interior wall, acoustic waves are radiated back to the apparatus. The apparatus detects the acoustic waves and measures the elapsed time between transmission of the electromagnetic energy and detection of the acoustic waves. From elapsed time measurements the dimensions of the interior walls are obtained.