Microsecond laser pulses with adjustable length

Nd:glass lasers are shown to generate microsecond pulses with an adjustable pulseform by using only intracavity components for which the laser pulseform is sensitive to the rate at which the cavity Q is increased. Lower rates give longer pulses, and by adjusting the intensity I(PC) of the light flux reaching the photocell from the beam-splitting plate, the magnitude of the photoelectric feedback is regulated, further increasing the pulse length. Experimental tests demonstrated greater pulseform control by varying I(PC) during the lasing, or by feeding a voltage pulse of suitable profile to the photocell. The laser was shown to generate a profiled pulse length of 2 microsec and energy of 0.5 J, and the ratio P(max)/P(min) reached 100.