Contents

02 July 1971
Vol 173, Issue 3991

About The Cover

Holographic interferogram revealing dangerous bonding defect located deep inside an automabile tire. By combining lasers and holography, the nondestructive method of ``holographic interferometry'' has introduced a new form of interferometry into optics, capable of revealing microscopic deformations on large-size objects. see page 11 [GC-OPTRONICS, Ann Arbor,Michigan]