Patent GB-1182462-A (GB)
Title: Signal Time-Division Multiplex Apparatus
Inventor: NISHIZAWA JUNICHI
IPC: H04J3/04
Filed: 1967-02-17
Abstract: 1,182,462. Electroluminescence. ZAIDAN HOJIN HANDOTAI KENKYU SHINKOKAI and HITACHI SEISAKUSHO K.K. 17 Feb., 1967 [19 Feb., 1966; 12 March, 1966; 25 March, 1966; 2 April, 1966; 25 April, 1966 (3)], No. 7717/67. Heading C4S. [Also in Divisions G5, H1, H3 and H4] A distributor includes means for connecting a number of signal sources sequentially to a common line or for connecting a line sequentially to a number of signal-responsive units under the control of and in step with the propagation of a switching signal along an active transmission line. One embodiment of the arrangement is shown in Fig. 3a in which the line consists of elements a 1 -a n , each containing a biased tunnel diode D as active element. An electric pulse from unit 31 travels down the line and appears at each tap in turn, so enabling transistors TRS 1 -TRS n  sequentially to pass signals detected by radiation detectors b 1 -b n  to pass to unit 32. In a similar arrangement signals from unit 32 are distributed to electroluminescent units. In other embodiments each transistor-detector combination TRS-b is replaced by a photo-diode, Figs. 3b-3d (not shown). By application of pulses to both ends of the line a logic function additional to the detection is obtained, Fig. 4c (not shown), one pulse being amplified and the other attenuated after the point of collision. By stacking a number of lines and detectors, and by pulsing each line in turn, a scanning matrix is evolved. The lines and detectors may be fabricated in layers as indicated in Fig. 6a. Radiation passes through a transparent insulating layer 61 and a transparent conducting layer 62 to a radiation-sensitive layer 63. This is backed by P-type silicon having N-type elements 64 embedded in it. Each row of elements provides an active transmission line, and adjacent rows are separated by insulators 70. There is a second conductive layer 66 and an insulating layer 67. The first elements in the various lines are connected to a distributer 68 (e.g. a delay line), the remaining elements being connected by lines 72. The distributer 68 pulses the first elements successively such that each line is scanned in turn, the signals passing to unit 54. By replacing the radiation sensitive layer 63 with a radiation emissive (e.g. luminescent) layer and the unit 54 with a signal source a display scan is obtained. If the lines are pulsed from both ends a pair of oppositely directed rasters is developed. Image pick-up and television viewing applications are instanced. The transmission line comprising photodiodes may be constructed from P-type (81) and N-type (82) material channelled as shown in Fig. 8a and having conductors (85-87). By suitable doping tunnel diodes (D) and photodiodes (PD) are formed. The electrode (85) may take a winding path over the P-type material to provide the required inductance, Figs. 8c-8d (not shown). Various alternative constructions using integrated circuit techniques are mentioned. In a further embodiment, Fig. 12a, laser diodes (142) are placed in parallel with the tunnel diodes (141). The laser diodes respond sequentially to a short pulse from unit (143). If the recurrence period of pulses from (143) is shorter than a certain value only the first pulse and those pulses with a spacing greater than that value will be propagated.