Air scattering standard for light scattering based optical instruments and tools

A method comprising:

• generating a beam of illumination;
• focusing the beam of illumination into a volume of air contained within a chamber of an inspection chamber;
• collecting a portion of illumination scattered from the volume of air;
• detecting, with a detector, the collected portion of illumination from one or more collection optics;
• determining a state of the beam of illumination at one or more times based on a comparison between an intensity of the illumination scattered from the volume of air and a predetermined intensity standard.

An inspection system comprising:

• one or more illumination sources configured to generate a beam of illumination;
• one or more illumination optics configured to focus the beam of illumination into a volume of air contained within a chamber of an inspection chamber;
• one or more collection optics configured to collect a portion of illumination scattered from the volume of air;
• a detector, wherein the detector is configured to receive the collected portion of illumination from the one or more collection optics;
• and
• a controller, the controller including one or more processors communicatively coupled to the detector, wherein the one or more processors are configured to execute a set of program instructions stored in memory, the set of program instructions configured to cause the one or more processors to:
• receive one or more signals from the detector indicative of an intensity of the illumination scattered from the volume of air;
• and
• determine an intensity of the beam of illumination at one or more times based on a comparison between the intensity of the illumination scattered from the volume of air and a predetermined intensity standard.

An inspection system comprising:

• one or more illumination sources configured to generate a beam of illumination;
• one or more illumination optics configured to focus the beam of illumination into a volume of air contained within a chamber of an inspection chamber;
• one or more collection optics configured to collect a portion of illumination scattered from the volume of air;
• a detector, wherein the detector is configured to receive the collected portion of illumination from the one or more collection optics;
• and
• a controller, the controller including one or more processors communicatively coupled to the detector, wherein the one or more processors are configured to execute a set of program instructions stored in memory, the set of program instructions configured to cause the one or more processors to:
• receive one or more signals from the detector indicative of an intensity of the illumination scattered from the volume of air;
• and
• determine a polarization of the beam of illumination at one or more times based on a comparison between the intensity of the illumination scattered from the volume of air and a predetermined intensity standard.