Patent ID: 8592762

Claim:
A method of using an image sensor in a particle-optical apparatus, the particle-optical apparatus comprising: a particle source for producing a beam of particles, acceleration means for accelerating the beam of particles, lenses to manipulate the beam of particles, sample position means for positioning a sample on a sample position, and a sensor for detecting an image of particles formed on it, the method comprising: providing a sample on the sample position, forming a first diffraction image on the sensor showing a high intensity peak at a first position, and lower intensity peaks at other positions, and forming a second diffraction image on the sensor after forming the first image, the second image displaced with respect to the first image, resulting in a different position of the high intensity peak on the sensor for the two images, as a result of which damage to the sensor or artifacts in the image due to prolonged overexposure of the sensor is decreased, wherein the high intensity peak of each of the images is the central, undiffracted peak.