Abstract A steady voltage applied to a voltage sensitive device such as a Kerr cell or a Pockels cell is caused to be interrupted by a sharp, brief, square pulse, during which the applied voltage is zero, by means of a single d.c. voltage generator operating through a series impedance into two transmission lines of substantially the same characteristic impedance. One line is connected between the generator (i.e., its series impedance) and the load, which is a high impedance, and the other line has one end connected to the generator (i.e., its series impedance) over a switch and its other end connected to a high impedance which acts as an effective open circuit. Closing the switch produces a series of substantially zero voltage intervals across the load, the period being determined by the combined length of the lines and the duty cycle by their relative length, but after the first few pulses the dissipation in the transmission lines and their terminations prevents the voltage from dropping all the way to zero, but for laser triggering only the first pulse is normally needed and the subsequent ones cause no disturbance.
A generator for producing electrical pulses having fast rise and fall times interrupting a steadily applied voltage by short periods of substantially zero output voltage, wherein said generator comprises a direct-current high-voltage source; a first transmission line connected at one end to a high impedance output load and connected at its other end over a high impedance to said high-voltage source, both said high impedances being high relative to the characteristic impedance of said transmission line; and a second transmission line of substantially the same characteristic impedance as said first line and of a length relative to that of said first line determined by the desired duty cycle of said pulses within the pulse period thereof, one end of said second line being terminated by as high impedance that is high relative to the characteristic impedance of the lines, and the other end being connected by means of a switch to that end of said first line at which said high impedance connected to said source is connected to said first line.
Claim 2
Dependent Claim
172 words
A generator for producing electrical pulses having fast rise and fall times interrupting a steadily applied voltage by short periods of substantially zero output voltage, wherein said generator comprises a direct-current high-voltage source; a first transmission line connected at one end to a high impedance output load and connected at its other end over a high impedance to said high-voltage source, both said high impedances being high relative to the characteristic impedance of said transmission line; and a second transmission line of substantially the same characteristic impedance as said first line and of a length relative to that of said first line determined by the desired duty cycle of said pulses within the pulse period thereof, one end of said second line being terminated by as high impedance that is high relative to the characteristic impedance of the lines, and the other end being connected by means of a switch to that end of said first line at which said high impedance connected to said source is connected to said first line.
Claim 3
Dependent Claim
13 words
A generator according to claim 1, wherein the transmission lines are coaxial cables.
Claim 4
Dependent Claim
22 words
A generator according to claim 1, wherein said first and second lines have relative lengths between the ratios of 5:1 and 1:5.