Method of examining a sample using a charged particle beam apparatus

A charged particle beam apparatus for examining a sample, comprising:

• A charged particle beam source for emitting a charged particle beam;
• A sample holder for holding a sample;
• An illuminator for directing the charged particle beam emitted from the charged particle beam source onto the sample;
• A first detector for detecting emissions of a first type originating from said sample in response to the illumination of said sample with charged particles emitted from said charged particle source;
• and
• A control unit including non-transitory memory for storing computer readable instructions, by executing the instructions by a processor, the control unit is configured to:
• Illuminate the sample with the charged particle beam;
• Detect emissions of the first type from the sample in response to the illumination;
• and
• Determine spectral information on emissions of a second type from the sample using a spectral information predicting algorithm, wherein the detected emissions of the first type is an input of said algorithm.