Abstract: A photoelectric data card system is disclosed in which the cards are transmissivity-coded, so that light of a particular wave length and intensity is transmitted in varying degrees of different code digit representing areas of the cards, and thus the intensity of the light emerging from each of these code digit representing areas can be photoelectrically interpreted as the value of the digit represented by that area. A laminated card for use in this system is disclosed in which the transmissivity levels of the digit representing areas are provided by halftone printing on an inner lamination of dark-pigmented plastic card stock, and the inner lamination is sealed between two white-pigmented laminations of plastic card stock, the white-pigmented laminations being pigmented to such an extent that neither the location of the digit representing areas nor the values of the digits represented can be determined by casual inspection of the card.