In relation to Trek non-contacting electrostatic voltmeter (ESVM) probes, what does the term “spot surface resolution” mean?
Spot surface resolution is the diameter of a spot on the surface which is actually being measured by the non-contacting ESVM probe. The diameter of the spot area being measured is largely influenced by the spacing between the probe and the surface being measured, as well as the probe’s aperture size. As a general rule of thumb for Trek’s electrostatic voltmeters, the ratio is 5:1. For example, using a standard Trek probe spaced at a distance of 2mm from the surface, the surface area being measured is a surface spot diameter of approximately 10mm. If the Trek probe-to-surface spacing is 3mm, the surface area diameter spot being measured is approximately 15mm. This ratio will vary somewhat between different models. Specific information for different probe models is available.
