Means and method for characterizing high power, ultra short laser pulses in a real time, on line manner

A method of characterizing short laser pulses comprising:

• a) generating a laser pulse having a wavelength in the order of about 10 .mu.m or less and a duration of less than 30 ps;
• b) generating a control laser beam;
• c) directing the laser pulse and the control laser beam at a first reflection switch;
• d) timing the control laser beam to be incident on the first reflection switch after a portion of the laser pulse has passed part way through the first reflection switch, thereby to reflect a remaining portion of the laser pulse and to skew it from the initial direction of the laser pulse in a predetermined manner;
• e) locating a second reflection switch to receive the reflected portion of the laser pulse;
• f) directing the control laser beam to be incident on the second reflection switch when the reflected portion of the laser pulse has passed part way through the second reflection switch to pass a transmitted or sliced portion of said reflected portion through the second reflection switch;
• g) locating a measuring means to receive said transmitted or sliced portion;
• h) measuring said transmitted or sliced portion to determine a physical length measurement that is convertible into a temporal pulselength of the laser pulse.

A method of characterizing high power, ultra short laser pulses in a real time, on line manner comprising steps of:

• a) generating a high power, ultra short laser pulse;
• b) positioning a first reflection switch to have the ultra short laser pulse incident thereon, the first reflection switch transmitting the ultra short laser pulse;
• c) generating a control laser pulse;
• d) directing the control laser pulse to be incident on the first reflection switch at an angle of about 90.degree. with respect to the first reflection switch when the ultra short laser pulse has passed part way through the first reflection switch, the control laser pulse causing the first reflection switch to change from transmitting the ultra short laser pulse to reflecting the ultra short laser pulse to cut off the portion of the ultra short laser pulse that has passed through the first reflection switch when the control pulse is incident on the first reflection switch and to reflect a portion of the ultra short laser pulse that has not passed through the first reflection switch when the control laser pulse is incident on the first reflection switch, thereby to define a reflected pulse;
• e) directing the reflected pulse toward a second reflection switch located spaced apart from the first reflection switch;
• f) directing the control laser pulse to be incident on the second reflection switch at an angle of about 90.degree. when the reflected laser pulse has passed part way through the second reflection switch, the control laser pulse causing the second reflection switch to change from transmitting the reflected laser pulse to reflecting the reflected laser pulse, thereby to cut off the portion of the reflected laser pulse that has passed through the second reflection switch when the control pulse is incident on the second reflection switch and to reflect a portion of the reflected laser pulse that has not passed through the second reflection switch when the control laser is incident on the second reflection switch to define a sliced pulse;
• g) directing the sliced pulse towards a measuring means;
• and
• h) measuring the spatial dimension of the sliced pulse.

A method of characterizing short laser pulses comprising:

• a) generating a short laser pulse having a temporal pulselength to be characterized;
• b) generating a control laser beam;
• c) converting the short laser pulse temporal pulselength into a physical pulselength by sequentially focusing the short laser pulse onto two reflection switches and focusing the control laser beam onto the two reflection switches in timed relation with the short laser pulse to impinge on each of the reflection switches at about a 90.degree. angle of incidence, thereby to permit a portion of the laser pulse incident on either of the reflection switches to pass through that reflection switch prior to the control laser beam impinging on that reflection switch and to reflect any remaining portion of the laser pulse;
• and
• d) physically measuring the physical pulselength of any portion of the laser pulse transmitted by the second reflection switch of the two reflection switches.