Patent GB-1316650-A (GB)
Title: Three-dimensional pattern generator
IPC: G06F3/147
Filed: 1970-11-27
Abstract: 1316650 Three dimensional display BATTELLE DEVELOPMENT CORP 27 Nov 1970 [28 Nov 1969 5 Nov 1970] 56472/70 Headings G4A G4H and G5C [Also in Division C4] A three dimension pattern display generator comprises a volume of material the optical properties of which may be modified in response to energy level changes, a means for generating the appropriate energy level changes within the volume, and a computing and control means adapted to receive input data specifying the locations of selected points within the volume and to compute control signals in response to the data which control signals are operative to control the generating means to cause the appropriate energy level changes at the selected points within the volume. Computing and control.-The computer system may be a stored programme or special purpose digital computer, a digital and an analogue computer, or a hybrid computer. In a preferred embodiment the computer is a serial stored programme digital computer. The computer has data line and manual inputs and is connected to a control logic and memory subsystem which acts as an interface with the display controls. The computer is interruptable in that it is arranged to service, e.g. a manual input request, and is arranged to communicate with the operator via a printer or indicator lights. A special purpose digital computer is described in which subtraction is performed by one's complement addition and division by successive subtractions and shifts until the remainder is negative. Multiplication is performed by forming the logical AND of successive bits of the multiplicand with the least significant bit in the multiplier and loading the result, through an adder which deals with carry bits which are stored in a flip-flop, into a partial product register. The contents of the partial product register are then shifted one place to the right and the cycle continues with the next bit of the multiplier. The computer is wired (or programmed) to perform calculations (details of which are given in the specification) and produce control instructions which are passed to the control logic and memory subsystem which directly controls the display system. A flag bit in the computer's output register is set each time an instruction is ready and is reset when the instruction is taken by the control subsystem. A special purpose digital computer employing table look-up may be used. The table of values may be stored in a read only memory. The table may be complete or a facility for interpolating between stored values may be provided. An analogue system for performing a particular calculation is also briefly described. Display.-The display (see also Division C4) consists of a volume which may be gas having suitable emission centres such as fluoride crystals doped with a rare earth, phosphors, &c. The volume may also be a liquid or solid with suitably distributed emission centres. The energy sources may be lasers, arc lamps, electron beams, electrons in conductors, or charged particle beams. The Specification gives a detailed description of the above and other embodiments. The energy beams are controlled by deflectors of known types, such as Bragg light deflectors. A cursor (light pen) is provided and may be used to insert or erase data from the display. The display system may be used to display in three dimensions aircraft positions in an air contro system or may be used as an output from and/or (in conjunction with the light pen) as an input to a computer.