Retina Display is a demo for the Commodore VIC20. This demo uses a new graphical display system. This graphical system is named Ultra-Hires Interlace mode and can be used on a NTSC VIC-20 with an 32 kByte RAM expansion. The screen can display 192 x 416 = 79872 pixels, that is 25% more than with a Commodore C64.
Retina Display demonstration on YouTube.