Basic triboelectric X-ray source using the rod and band architecture.
A motor rotates a band around a rod. This is generates a charge density on the band. The electric charge will then move to the target, generating X-rays. The whole system is placed inside a vacuum chamber.
This is the M4 X-ray source created by Tribogenics Inc. It was used in the Watson XRF device.
Theory of electron emission from a charged polymer surface
While at Tribogenics, I developed a simple electron emission theory from a charged polymer surface. This was used to both explain and model the discharge of charge from a charged polymer surface due to triboelectric charging. This theory laid the groundwork for my simulations of the device and developed an understanding of the electrostatics of the system.
COMSOL Simulations of the X-ray cartridge.
Using the charge distribution equation:
Which can be reduced to:
A device to measure charge on a polymer band.
This is a device that can measure the charge density of a polymer band. One cantilever is used to produce a 1D map of the charge density on the band. Two or more cantilevers are needed to make a 2D mapping.
COMSOL simulations of the charge measurement device
Models used
Using the charge density function we get the following response:
