A second wedge beam splitter deflected portions of the beam into detectors to measure the pulse energy. For single-pulse exposures, a Laser Probe RjP-765a detector (Laser Probe Inc., Utica, New York, USA) read out by a Laser Probe Rj-7620 Dual Channel Energy Meter was used to measure the pulse energy in the reference beam. Prior to exposing a retina, a Laser Probe RjP-735 detector was placed at the eye position to measure the energy incident to the eye. The ratio of the two measurements was used to calibrate the exposure system for single-pulse exposures. For multiple-pulse exposures, an International Light Technologies SED033 detector (International Light Technologies, Peabody, Massachusetts, USA) read out by an IL1700 pulse integrator was used to measure the total energy in the reference beam. This system was calibrated by placing a Scientech model 380101 detector (Scientech, Boulder, Colorado, USA) read out by a Scientech model 36-5002T2 power meter placed at the eye position prior to retinal exposures.