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We present state-of-the-art mid-infrared high-reflectivity low-loss mirrors at 4.54 µm based on substrate-transferred crystalline coatings. Transmission losses of ~145 ppm and excess losses of

We present common path-based optical terminals designed for full-duplex free-space optical (FSO) communications to apply for unmanned aerial vehicles (UAVs) to ground communication. The FSO terminals were carefully designed by taking into account flight issues of UAVs. Simple and compact FSO terminals were produced by integrating optical components for transmitting and receiving data-carrying beams and a beacon beam to track the other party FSO terminal. Preliminary experiment that was carried out with the FSO terminals installed at fixed position showed a 1.25-Gbps full-duplex error-free communication link for a bit error rate of ~10−12 over 50 m.

We investigated the performance of an injection-seeded THz-wave parametric generator at a repetition frequency in the 100-kHz regime. We obtained a THz-wave output of ~30 μW in the range of 1.0–2.8 THz.

Ground-based high-resolution Fourier transform spectrometer (FTS) and portable FTS have been used for column measurements of greenhouse gases. We present measurement campaigns for quantifying CO2 emission from a large point source with two portable FTSs.

We report on studies of tuning characteristics and modulation properties of a distributed feedback continuous wave quantum cascade laser centered at 7.83 μm in detection of mid-IR line transitions of methane, nitrous oxide and water-vapor.

The differential optical absorption spectroscopy was developed to retrieve the particle extinction coefficient. With the extinction coefficient, the number size distribution from 0.1μm to 1.25μ m was retrieved by a step function.

Optical Turbulence estimates made from Numerical Weather Prediction using a modified approach based on Ciddor’s refractivity parametrization with temperature and hydrometer contributions is shown to predict measured 880nmscintillation better than a standard approach.

NO3 radical is the most critical night oxidant. Observation of NO3 radicals was performed in suburb of Hefei using differential optical absorption spectroscopy from Apr 28 to May 8, 2014.

Here we present how the Far-infrared Interferometer Instrument Simulator (FIInS) is used to simulate an observation of astronomical targets. The selection of the instrument parameters (spectral and spatial) is discussed and the obtained results analyzed.

The Hyperspectral Imager for the Coastal Ocean (HICO) is flying on the International Space Station. Here we give a brief overview of HICO on-orbit performance and suggest future directions for imaging the coastal ocean.

We demonstrate a fast frequency tuning of a terahertz wire-laser. Using a piezo-actuator and a MEMS-plunger enables a tuning speed up to ∼15 KHz. Improved bonding-pad design of wire-lasers leads to larger fabrication yield and better mode discrimination.

More than 1000-nm-wide frequency comb centered at 4.9 µm was produced in an OPO based on orientation-patterned GaAs (OP-GaAs), synchronously pumped at 182 MHz repetition rate by femtosecond Cr:ZnSe laser pulses at 2.45 µm.

A narrow linewidth thulium fiber laser is tuned from 1945 – 2090 nm to investigate atmospheric transmission at 1 km. Results confirm simulations with high transmission >2025 nm and strong atmospheric absorption

Improvements are discussed regarding the development of ice cloud bulk scattering models based on a comprehensive set of microphysical in situ measurements and a set of modeled ice particles used for light scattering calculations.

We present multi-layer CO retrieval from atmospheric data acquired simultaneously in the solar reflective region near 2330 nm and the thermal emissive region 4680 nm by the demonstration version IIP Tropospheric Infrared Mapping Spectrometers (TIMS).

We discuss how cloud phase is inferred from MODIS and AIRS data and compare global results with those obtained from analysis of CALIPSO depolarization measurements.

We discuss the difficulties inherent in the bispectral infrared thermodynamic phase retrieval of potentially mixed-phase clouds and how the phase retrievals of these clouds may be improved by including hyperspectral infrared measurements.

Multilayer cloud detection using, in part, a water vapor absorption band at 0.94 µm has been implemented in the recent MODIS Collection 5 processing stream. Evaluation with active sensor(s) will be discussed.

We develop ice cloud bulk scattering models that are based on a comprehensive set of microphysical in situ measurements of ice clouds, and a set of modeled ice particles used for light scattering calculations.

A TiCl4/He plasma is observed by high resolution double-modulation FTS using concentration-modulation as a selective detection method. Analysis of the C4Δ-X4Φ Δv=0 transitions of 48Ti35Cl reveals perturbations affecting the C 4Δ1/2 sub-state.

This paper describes the performances of the ACE-FTS Flight Model (FM) as measured during the verification campaign. It also presents the expected on-orbit performances of the instrument in terms of key parameters like signal-to-noise ratio and resolution.

A miniature FTS instrument where the moving mirror runs on a MEMS-based guiding mechanism is presented. Spectra obtained with a 10 x 15 x 2.5 cm brassboard at 0.1 cm-1 resolution will be discussed.

The German Aerospace Center (DLR) Oberpaffenhofen/Germany operates a high resolution Fourier-Transform-Spectrometer (Bruker IFS 120 HR). The photomectric characterzied instrument was primarily used for precision measurements of trace gases in the laboratory (spectral resolution ≥ 0.001cm-1). The presented extension allows emission and absorption measurements in the atmosphere. Compared to absorption measurements emission measurements are independent of extraterrestrial sources (sun, moon), thus, making the instrument more versatile. Our instrument is not intended to be used for operational atmospheric measurements. It will mainly be used for developing new data products and methods, exploiting the synergy from absorption/emission measurements, laboratory spectroscopy an FT instrumentation expertise. In the paper the instrumental setup is shown and first measurements are presented.

The MODIS Airborne Simulator (MAS), which flies on NASA's high altitude ER-2 aircraft, has received increasing attention as the launch date of the Moderate Resolution Imaging Spectro-radiometer (MODIS) on the EOS AM-1 platform nears (mid 1999), since 19 of the 50 MAS spectral bands emulate MODIS spectral bands.