A novel polarization interferometer for measuring upper atmospheric winds

A static polarization interferometer for measuring upper atmospheric winds is presented,based on two Savart plates with their optical axes perpendicular to each other.The principle and characteristics of the interferometer are described.The interferometer with a wide field of view can offer a stable benchmark optical path difference over a specified spectral region of 0.55-0.63 μm because there are no quarter wave plates.Since the instrument employs a straight line common-path configuration but without moving parts and slits,it is very compact,simple,inherently robust and has high throughput.The paper is limited to a theoretical analysis.

Measurement of Martian atmospheric winds by the O_(2) 1.27 μm airglow observations using Doppler Michelson Interferometry: A concept study

China’s Mars exploration mission has stimulated tremendous interest in planetary science exploration recently.To propose potential scientific research projects,this study presents a concept simulation for the measurement of Martian atmospheric winds using the Doppler Michelson interferometry technique.The simulation is based on the satellite instrument initially designed for the Dynamic Atmosphere Mars Observer(DYNAMO)project to measure vertical profiles of winds from the 1.27μm airglow observations in the Martian atmosphere.A comprehensive DYNAMO measurement simulation forward model based on an orbit submodel,an atmospheric background field submodel,and an instrument submodel is developed using the Michelson equation.The simulated interferogram signal over the field of view(FOV)calculated by the forward model is associated with the filter transmittance function,column emission rate of airglow,wind velocity,temperature,and the Michelson phase.The agreement between the derived atmospheric signals from the simulated interferogram without altitude inversion and the input parameters used to initiate the forward model confirms the validity of the forward model.

Dependence of interferogram phase on incident wavenumber and phase stability of Doppler asymmetric spatial heterodyne spectroscopy

Instrument drifts introduce additional phase errors into atmospheric wind measurement of Doppler asymmetric spatial heterodyne spectroscopy (DASH). Aiming at the phase sensitivity of DASH to instrument drifts, in this paper we calculate the optical path difference (OPD) and present an accurate formula of DASH interferogram. By controlling variables in computational ray-tracing simulations and laboratory experiments, it is indicated that initial phase is directly determined by incident wavenumber, OPD offset and field of view (FOV). Accordingly, it is indicated that retrieved phase of DASH is sensitive to slight structural change caused by instrument drift, which provides the proof of necessary-to-track and -correct phase errors from instrument drifts.