Calibration for tuneable diode lidar gas detection
US12339264B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 2024 |
| Grant date | Jun 24, 2025 |
| Priority date | — |
| Expiry date | Jul 26, 2044 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/399
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Calibration methods for lidar equipment are disclosed. In some embodiments, the lidar equipment is provided with an internal gas reference cell with a known concentration of the gas of interest, such as methane (CH4), which provides known absorptions at wavelengths particular to the gas. The lidar system laser beam passes through the gas reference cell before scanning a scene, and provides a known level of gas absorption at those known absorption wavelengths. This guarantees there is a minimum signal to be detected by the lidar system. In some embodiments, the lidar equipment is provided with an external calibration unit having one or more gas sample cells with predetermined lengths and known concentrations of the gas of interest. By making lidar measurements using an arrangement of these calibrated cells, adjustments to the parameters used in the algorithms relating detected photon counts with gas concentration may be made.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.