Video rate mid-infrared photothermal microscopy system using synchronized laser scanning

A mid-infrared photothermal microscopy system for imaging a sample comprising:

• a mid-infrared optical source configured to generate a mid-infrared beam;
• an objective arranged to focus the mid-infrared beam to a IR focal spot at the sample;
• a probe light source configured to generate a probe light beam that is focused to at least partially overlap the IR focal spot at the sample;
• a first laser scanner configured to scan the IR focal spot across the sample;
• and
• a second laser scanner configured to synchronously scan the focused probe beam to maintain at least partial overlap with the IR focal spot.

A method of operating a photothermal infrared microscope comprising:

• illuminating a sample with a mid-infrared beam focused to an IR focal spot using an objective;
• illuminating the sample with a probe light beam focused to at least partially overlap the IR focal spot;
• synchronously scanning the IR focal spot and probe light beam across the sample using first and second laser scanners while maintaining at least partial overlap between the IR focal spot and probe light beam;
• and
• detecting probe light from the sample to generate a reconstructed image.