Telephone subscriber's apparatus for signalling decimal digit values represented in printed form

Claim 1

Apparatus at a telephone subscriber's station for signalling over an associated telephone line decimal digit values which are each represented on a generally planar surface as a series of adjacent areas of detectably differing light reflecting properties, comprising A. a set of ten push-buttons, one for each decimal digit valve, B. signalling means for signalling the identity of a wanted subscriber, said signalling means being arranged to be connected to said associated telephone line, C. means to apply to said signalling means electric signals representing decimal digit values in response to operation of respective ones of said push-buttons, D. manually-operable light pen means to illuminate a series of said areas in turn and to derive a series of signal voltages of values representing decimal digits, dependent upon the respective levels of light reflected from said series of areas, E. means temporarily to store said signal voltages, and F. convertor means to apply to said signalling means electric signals in respect of the decimal digit value represented by said stored signal voltages.