Measurement of laser photoelectron image degradation at high current densities

Loss of image resolution and contrast in a laser-illuminated photoelectron microscope have been measured for current densities up to 1 A/cm²and light intensities up to about 2 MW/cm². Contrast is greatly reduced at these levels for detail less than a few microns in size, although images below 0.1 A/cm²contain 0.1 μm detail. Comparison to theory shows that the aberrations are larger than predicted.