Patent 11592652 was granted and assigned to California Institute of Technology on February, 2023 by the United States Patent and Trademark Office.
Apparatus and methods for measuring infrared absorption of a sample that includes delivering a pulse of infrared radiation to a region of the sample, delivering pulses of radiation of a shorter wavelength than infrared radiation to a sub-region within the region, and using one or more properties of the induced photoacoustic signals to create a signal indicative of infrared absorption of the sub-region of the sample.