Abstract: An address boundary detector is disclosed that functions with an arithmetic logic unit (ALU) in a computer processor while the ALU generates addresses by adding an offset or displacement to a base address. The detector monitors bits of addresses to determine whether a data item can be completely stored within the same block or page of memory as that addressed by the base address from which it was derived.

Abstract: A fast axial flow gas laser apparatus comprising an at least essentially closed loop defining a flow path for a laser gas, an arrangement for exciting gas flowing in the loop of the apparatus to cause the gas to lase, and a regenerative compressor for flowing gas through the closed loop along the flow path. The compressor is capable of operating with a pressure ratio sufficient to flow the gas along at least a portion of the loop at a speed at least half the speed of sound in the gas with inlet pressures of only a small fraction of an atmosphere. The uniform discharge pressure of the compressor results in a uniform laser discharge or output. A positive pressure fluid pressure seal prevents lubricant at a bearing support for the impeller shaft of the compressor from moving to the impeller and possibly contaminating the laser gas being compressed thereby and also prevents surrounding air from contaminating the laser gas.

Abstract: A multifunction arithmetic indicator that is associated with and controlled by an arithmetic logic unit (ALU) to store standard arithmetic indicator information such as overflow, carry, arithmetic sign and all bits equal zero that are generated by the ALU when processing binary information. A control unit sends control signals to multiplexers in the multifunction arithmetic indicator that cause the selection of appropriate arithmetic indicator information from the ALU, no matter what the bit length of binary words being processed by the ALU. The selected indicator information is stored in a register for later use.

Abstract: Memory failure detection apparatus is disclosed which is used with a large capacity memory that is organized in banks of memory, and with which error correction circuitry is used to correct correctable errors and provide an indication of same. The detection apparatus is responsive to the error indications and to a bank select addressing signal to provide and store error counts for a bank or banks of memory located on each memory board. A system processor periodically reads the error counts and responds to same to provide a maintenance message indicating that a specific memory board is to be replaced.

Abstract: A laser fluid control apparatus and method provide selective, precise control of the fluid supplied to the laser. The flow of the fluid to the laser can be automatically adjusted according to a selected, programmed control to provide a high volume of the fluid to the laser during initial operation of the laser for a quick warm-up of the laser and a reduced volume after the laser has warmed-up for more economical operation of the laser. Different fluid mixes can also be provided for enhancing laser performance. A control for pulsed or continuous wave laser operation can be actuated to automatically change the composition of the fluid supplied to the laser for continuous wave laser operation as compared to that for pulsed operation.

Abstract: A laser optical element mounting arrangement and method are disclosed wherein a laser optical element is mounted to a laser mounting support member. The mounting support member has a smooth surface to which a surface of the optical element is engaged to form a vacuum seal between the optical element and the support member. The seal is accomplished with the application of only light pressure contact between the respective surfaces at ambient temperature and without the need for a sealant.

Abstract: An improved method of laser processing of a material by directing a laser beam against the material comprises providing the beam with a power waveform with respect to time characterized by a plurality of peak power pulses and a predetermined CW power level between the peak power pulses such that the average beam power maintained is equal to or greater than the predetermined CW power level of the beam. The method is particularly adapted for cutting material such as aluminum, copper and stainless steel with improved cut quality at a relatively high cutting speed and for welding.

Abstract: An axial flow gas transport laser comprising an excitation tube through which gas flows along an axis of the tube, an inlet arrangement to feed gas towards the excitation tube and an outlet arrangement to discharge gas from the excitation tube. At least one of the inlet and outlet arrangements comprises a circumferential opening arrangement evenly distributed along the periphery of the excitation tube, substantially in a cross-section plane of the tube. A gas flow channel arrangement to the opening arrangement is directed at least substantially in the direction of the excitation tube axis and into the excitation tube at the opening arrangement for preventing wide-areal turbulances of the gas flowing in the excitation tube.

Abstract: A method of lasing gas, a fast axial flow gas laser and an excitation tube for a fast axial flow gas laser are disclosed. Increased thermal energy per mass flow unit of the gas flowing through the excitation tube of the laser can be applied to the gas by controlling at least along a part of the tube the extent of a central area of higher speed gas flow which is surrounded by a circumferential low speed, speed dependent boundary layer by steadily varying the cross-section area of the excitation tube at least along the part thereof to compensate for the circumferential low speed boundary layer.