Diagnostic techniques with a computer controlled beam analyzer

The beam analyzer is a very useful tool for evaluation of beams from electron guns. Due to advances in computers and automation, modern beam analyzers are extremely versatile, accurate, fast and precise. Rapid graphic presentation of test data in a three-dimensional format allows the engineer to routinely test for uniformity of cathode emission, beam laminarity and quality of gun fabrication. Any changes in cathode emission, off center placement or tilt of parts which may have occurred during fabrication can be observed and diagnosed from the three-dimensional current density beam profiles. Performance of non-emissive grids or effective ness of grid coatings can be verified. Anomalies in cathode emission, whether due to non-emissive areas or chips or cracks, appear as an irregularity in a cross-section, pseudo-three-dimensional presentation. The cathode edge emission, and change in cathode emission vs. life are easily identified.