The EyeTap (also known as Generation-2 Glass"GlassEyes": The Theory of EyeTap Digital Eye Glass, supplemental material for IEEE Technology and Society, Volume Vol. 31, Number 3, 2012, pp. 10–14.) captures rays of light that would otherwise pass through the center of the lens of the wearer's eye, and substitutes synthetic computer-controlled light for each ray of real light. The Generation-4 Glass (Laser EyeTap) is similar to the VRD (i.e. it uses a computer-controlled laser light source) except that it also has infinite depth of focus and causes the eye itself to, in effect, function as both a camera and a display by way of exact alignment with the eye and resynthesis (in laser light) of rays of light entering the eye."Intelligent Image Processing", John Wiley and Sons, 2001, , 384 p.
The EyeTap (also known as Generation-2 Glass"GlassEyes" The Theory of EyeTap Digital Eye Glass supplemental material for IEEE Technology and Society Volume Vol 31 Number 3 2012 pp 10–14) captures rays of light that would otherwise pass through the center of the lens of the wearer's eye and substitutes synthetic computer-controlled light for each ray of real light The Generation-4 Glass (Laser EyeTap) is similar to the VRD (ie it uses a computer-controlled laser light source) except that it also has infinite depth of focus and causes the eye itself to in effect function as both a camera and a display by way of exact alignment with the eye and resynthesis (in laser light) of rays of light entering the eye"Intelligent Image Processing" John Wiley and Sons 2001  384 p