Abstract: A method for aligning a projected beam on a reflector in a reflective-type beam detector, the method including adjusting the projected beam so as to: project on to substantially all, if not all, of a reflective surface of the reflector; or project on to at least a portion of a reflective surface of the reflector until a constant, or within a predetermined threshold of a constant, signal is received from the reflector; and detecting one or more edges of the reflective surface of the reflector and thereby: centering the projected beam, so as to align an approximate center of the projected beam on, or within a predetermined threshold of, an approximate center of the reflective surface of the reflector; and/or determining a shape or profile of the reflector.

Abstract: A method for adjusting the timing of beam projections in a beam detector. The method includes projecting a beam for the purpose of detecting obscuration of the beam and, if a level of signal of the beam detected is less than a threshold for each of a number of consecutive projections or for each consecutive projection over a pre-determined time period, initiating a warning, signalling an alarm or otherwise reacting. The method further includes adjusting the timing of projecting the beam from a nominal transmit interval ‘T’ to be within a window time-period ‘W’ extending from an amount before to an amount after the nominal transmit interval ‘T’.

Abstract: A method for adjusting the timing of beam projections in a beam detector. The method includes projecting a beam for the purpose of detecting obscuration of the beam and, if a level of signal of the beam detected is less than a threshold for each of a number of consecutive projections or for each consecutive projection over a pre-determined time period, initiating a warning, signalling an alarm or otherwise reacting. The method further includes adjusting the timing of projecting the beam from a nominal transmit interval ‘T’ to be within a window time-period ‘W’ extending from an amount before to an amount after the nominal transmit interval ‘T’.

Abstract: A method for aligning a projected beam on a reflector in a reflective-type beam detector, the method including adjusting the projected beam so as to: project on to substantially all, if not all, of a reflective surface of the reflector; or project on to at least a portion of a reflective surface of the reflector until a constant, or within a predetermined threshold of a constant, signal is received from the reflector; and detecting one or more edges of the reflective surface of the reflector and thereby: centering the projected beam, so as to align an approximate center of the projected beam on, or within a predetermined threshold of, an approximate center of the reflective surface of the reflector; and/or determining a shape or profile of the reflector.