Accession Number : ADD012852
Title : Total Optical Loss Measurement Device.
Descriptive Note : Patent,
Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC
Personal Author(s) : Rahn,John P ; Marrs,C D
Report Date : 25 Nov 1986
Pagination or Media Count : 5
Abstract : The total optical loss caused by laser induced damage to an optical component is measured by monitoring the phase shift during mirror reflectance or transmission. The phase shift is directly proportional to the amount of loss. A secondary laser illuminates the area under test with a coherent light beam well below the component's damage threshold. This reference beam is modulated. The reflected or transmitted beam is monitored by a photomultiplier tube whose output is fed to a lock-in circuit. The lock in circuit compares the phase of the received light to the induced modulation.
Descriptors : *PATENTS, *LASER DAMAGE, *PHASE SHIFT, *OPTICAL DETECTION, BEAMS(RADIATION), COHERENT OPTICAL RADIATION, MODULATION, CIRCUITS, LOSSES, OPTICAL PROPERTIES, PHOTOMULTIPLIER TUBES, THRESHOLD EFFECTS, MIRRORS, REFLECTANCE, MEASURING INSTRUMENTS, TRANSMITTANCE, LOCKING(ELECTRONICS), LASER BEAMS
Subject Categories : Optics
Distribution Statement : APPROVED FOR PUBLIC RELEASE