Interestingly, a three-colour 2 x 2 square-grid tile game was invented in 1988 by Bob Vertes, using the same rules for playing and scoring as Maureen Hiron's Continuo.
Can you find the complete set of three-colour 2 x 2 MacMahon (Vertes' Vertigo) squares?
It is prepared in three different types, optimised respectively for three-colour continuous wave laser exposed reflection holograms, for pulse laser reflection holograms and for colour transmission holograms.
The sensitivity of the emulsion means relatively short exposure times: they quote 20 seconds for a 30 x 40 cm Three-colour Denisyuk hologram with the 20mW HeNe the lowest power of the lasers.
The 80 000-pixel, three-colour
LED display is linked to three computers, which generate two tickers of stok quotations that broaden and fan up, or narrow and dive down on the screens to colourfully dramatize shifts in price.