Optical Characterization, Visual Function, and Pursuit Tracking Performance Using a 532 nm Reflecting Holographic Filter.

摘要

A series of tests, involving the optical characterization, visual function, and pursuit tracking, were conducted to evaluate a newly developed laser ocular protective filter. The filter, a reflecting holograph, was designed to provide narrow hand protection against the doubled neodymium (532 nm) wavelength. Optical characterization of the material was determined by measuring broad band radiant transmission through the filter, photopic luminous transmission, optical density (OD) at 532 nm, variation of OD as a function of position, and the relationship between OD and the angle of incidence. Tests of visual function included the Snellen Acuity Chart, Arden Contrast Sensitivity Test, and Farnsworth Munsell 100 Hue Test. Pursuit tracking was evaluated using the BLASER tracking simulator which utilizes a terrain board model with moving targets and a viscous-damped tracking device. The optical characterization test results showed that at the 530 nm rejection band the holographic filter at the 50% transmission point had a band width of 30 nm and a 3.7 OD was achieved over much of the filter. The visual functions test indicated that the subjects had difficulty in color discrimination involving blue and green. No systematic differences were found on the contrast sensitivity test or Snellen Acuity Test.