Assessment of digital light processing (DLP) projector stimulators for visual electrophysiology

This study consisted of two sections. The first was a photometric study of two DLP laser projectors (Viewsonic LS831WU and HiSense 100L5FTUK) to assess luminance, contrast, spectral and temporal characteristics of the stimulus. The second was a physiological study comparing pattern electroretinograms (PERG) and visual evoked potentials (PVEPs) amplitudes and peak-times recorded using a DLP laser projector, photometrically and spatially matched to existing plasma VDUs at our institution (Pioneer Electronics Corporation, PDP422MXE).ResultsThe Viewsonic DLP laser projector was capable of high luminance levels (0 –587.5 cd/m2) whilst maintaining contrast above 93%. The temporal properties showed fast rise and fall times of 0.5 –1 ms and 0.5–1 ms, respectively, without any transient luminance change with reversals. The device required a warm-up time of at least 2 min until reaching near maximal luminance. The second (Hisense) device was observed to have a detrimental input lag jitter so was not used for any further analysis. PERGs and PVEPs showed high agreement and correlation (r = 0.766–0.905) between the Viewsonic DLP device and existing plasma VDUs. No significant differences were observed for P50 and P100 peak-time (p =  >  0.05), however P50, N95 and P100 amplitudes were all significantly larger for the DLP device (p =  <  0.05).DiscussionThe DLP laser projector tested in this study is a viable and practical replacement VDU for clinical ...
Source: Documenta Ophthalmologica - Category: Opthalmology Source Type: research