It’s a 16×16 LED matrix, driven without multiplexing, with a little logic on board to allow a PC to draw on the display connected to the parallel port. It was really bright, with just 16 of the 256 leds turned on, it was impossible to look directly at the display.
I built then a stand-alone controller, with some image sequence stored on EPROM, and placed all in a custom built aluminium box. This was used as a sample to show display capabilities to potential customers.
Obviously the customer kept the 16×16 version But I kept for me the very first 8×8 prototype (the one in the picture), entirely wired by hand.