Eye-safety analysis of current laser-based scanned-beam projection systems

Edward Buckley (SID Member) Abstract — Scanned-beam projection systems have attracted much interest recently, with claimed advantages including power efficiency and potential miniaturization consistent with embedding in mobile devices. However, the laser-safety classification and concomitant performance implications, which are arguably the most important issues pertaining to this technology, remain widely misunderstood. In this paper, Class 1 and 2 laser-safety radiometric image power limits for scanned-beam systems are derived with reference to the IEC 60825-1 standard. By calculating the equivalent photometric measure of luminous flux, it is possible to show that the brightness limits for scannedbeam projection systems using current technology are approximately 1 and 17 lm for Class 1 and 2 safety classifications, respectively.