Heterodyne detection system and method

摘要

An active heterodyne detection system comprises a continuously tuneable laser source (1) emitting infra-red radiation, means (8) to split the infra-red radiation into a first part and a second part, means (4) to provide a frequency shift between the first part and the second part, means (8, 9) to direct the first part of the infra-red radiation to a target (2), means (4) to provide the second part of the infra-red radiation as a local oscillator, means (8, 9) to collect a scattered component of the first part of the infra-red light from the target (2), and means (5) to mix the scattered component and the local oscillator and route them to a detector (3) for heterodyne detection over a continuous spectral range. A method of active heterodyne detection over a continuous spectral range is also disclosed.

主权项

1. An active heterodyne detection system comprising a continuously tuneable laser source emitting infra-red radiation, a beamsplitter configured to split the infra-red radiation into a first part and a second part, a frequency shifting device configured to provide a frequency shift between the first part and the second part, beam direction optics configured to direct the first part of the infra-red radiation to a target, beam collection optics configured to collect a scattered component of the first part of the infra-red light from the target, wherein a local oscillator comprises the second part of the infra-red radiation and wherein the active heterodyne detection system further comprises a mixer and a detector, wherein the mixer is adapted to mix the scattered component and the local oscillator and to route the mixed scattered component and local oscillator to the detector and wherein the detector is adapted for heterodyne detection over a continuous spectral range.