Radiant energy – Photocells; circuits and apparatus – Photocell controlled circuit
Patent
1980-05-27
1982-03-16
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Photocell controlled circuit
356215, H01J 4014
Patent
active
043202896
ABSTRACT:
Apparatus for automatically detecting and measuring the energy of laser pes over a wide range of energy levels and in the presence of high ambient light levels. The current produced by a laser pulse striking a photoconductive detector is integrated by a capacitor to obtain a voltage across the capacitor which is proportional to the total energy incident on the detector during the pulse. The total energy of the pulse is then determined by measuring the time from when the capacitor voltage crosses a reference level during current integration to the time when the capacitor voltage, discharging through a resistor recrosses the reference voltage. The leading edge of the capacitor charging voltage is used to couple a high frequency oscillator to the input of a counter. The oscillator is then decoupled from the counter when the voltage of the discharging capacitor crosses a reference level. The count in the counter is transferred to a shift register for transmission to a data processing device. The effects of the ambient light are automatically compensated for with an interrupted feedback loop in which the loop is opened when a laser pulse is detected and the feedback held at the prepulse level for the duration of the RC discharge time.
REFERENCES:
patent: 3732491 (1973-05-01), Battista
patent: 3999061 (1976-12-01), McLaughlin et al.
patent: 4174177 (1979-11-01), Gardner et al.
Blattel Raymond J.
Godwin Charles L.
White Jack R.
Beers Robert F.
Daubenspeck William C.
Nelms David C.
St. Amand Joseph M.
The United States of America as represented by the Secretary of
LandOfFree
Precision laser pulse radiometer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Precision laser pulse radiometer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Precision laser pulse radiometer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1643113