Non-contact photoacoustic spectrophotometry insensitive to light scattering
US10955335B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2019 |
| Grant date | Mar 23, 2021 |
| Priority date | — |
| Expiry date | Jun 26, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/088
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A non-contact photoacoustic spectrophotometry system is configured to measure an absorption spectrum of a material. The system includes a modulated light source such as tunable pulsed laser that generates laser pulses to produce photoacoustic signals in the material. A non-contact detector monitors the surface of the container for the material. The detector includes a second light source, such as a continuous wave laser, focused on the surface of the container, and transmits reflected light to an interferometer, for example, a Sagnac interferometer. The interferometer produces an interference signal from the received light that is proportional to the acoustic pressure, which is transmitted to a computer to calculate an absorption coefficient. Using a plurality of wavelengths from the tunable pulsed laser, an absorption spectrum may be generated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.