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Step 3
Our basic explanation is split into several steps
Putting it all together the complete electron optical system consists of the shielded magnet,
the CHA with an input and output lens, and an image detector.
This figure is an illustration of the complete electron optical path:

1. The sample sits inside a strong magnetic field and is illuminated using monochromatic x-ray photons.

2. Photoelectrons from the sample travel down the magnetic field lines until they reach the aperture on the axis of the magnetic field.

3. When the photoelectrons leave the magnetic field they still have momentum from the magnetic field (the Vector potential) and form
an angular image of the sample.

4. Using an electrostatic cylindrical lens the angular image is transferred from the exit aperture of the magnet to the input of the CHA.

5. The CHA is double focusing and images the now monochromatic angular electron image onto an output aperture.

6. The monochromatic angular image is focused into a plane image. A multi channel plate (MCP) is used to amplifier the electron
image which is accelerated onto a phosphor screen.

7. The image on the phosphor screen is captured with a CCD camera outside the vacuum system
How it works