Physics Domain - research topics of the Optics and Associated Techniques (DOTA)

Scientific Officer

PHY topics at the DOTA department

• Optoelectronics: photodetection and nanophotonics DOTA
• Environment and signatures for optronic sensors DOTA
• Fiber lasers, lidars and 3D imagers DOTA
• Active and passive remote sensing DOTA
• Wave surface control, adaptive optics DOTA
• Optical sensors and hyperspectral imagers DOTA

 PHY stands for the Physics Scientific Domain of ONERA

 

Optoelectronics: photodetection and nanophotonics

DOTA Patrick Bouchon, Sophie Derelle. (POC name.surname@onera.fr)

Areas of excellence

• Infrared photodetection: modeling, pixel FTM, pixel/matrix characterization, noise, cryogenics, semiconductor physics, quantum heterostructures
•  Low light level sensors
• Emerging infrared technologies: quantum dots, type 2 superlattices, gallium-free superlattices, nanostructured detectors, nanostructured filtersTerahertz and millimeter waves: terahertz spectroscopy, terahertz detection, terahertz imaging, THz-IR conversion
• Nanophotonics: metamaterials, metasurfaces, plasmonics, nano-antennas, 2D
• materials, optical phase masks for phase and polarization control, ENZ metamaterials, doped semiconductors, quantum dots
• Electromagnetic modeling: modal methods, finite elements, inverse design, optimization
• Light-matter interaction at the nano scale: nonlinear effects (SHG, DFG, Kerr effect, 4-wave mixing), SEIRA, SPR, infrared ellipsometry, near-field studies.
• Nanothermics: thermal emission, nanosources, thermal detection, thermal conversion, heat transfer in nanostructures

Examples

Nightglow radiation study

 

 

 

 

 

 
 

The MATISSE radiative transfer code

 

 

 

 

 

 

 

 

Modeling the optical and infrared signatures of aircraft and satellites

The DOTA department is developing the CRIRA and SIRIUS tools for modeling the optical and infrared signatures of aircraft and satellites. By signature we mean all the information used to characterize the object's radiation: intensity, luminance images, spectra and polarization. The aim is to provide representative simulations of these objects in order to respond to the needs of dimensioning or evaluating the optronic sensors that observe them.

The latest developments in these tools concern stealth aircraft, emerging hypersonic aircraft and satellite surveillance.

 

Fiber lasers, lidars and 3D imagers

DOTA Nicolas Cézard, Laurent Lombard. (POC name.surname@onera.fr)

Scientific and technical skills:

• Laser-matter interaction: materials and atmosphere, scattering media, all weather conditions
• Energetic, temporal, spectral and spatial characterization of laser beams (e.g. M², RIN, phase noise, etc.)
• Modeling physical phenomena in passive and doped optical fibers
• Photodetection techniques and associated signal processing: heterodyne detection, photon counting, matrix sensors
• Laser modulation/Lidar architecture/signal processing co-design (e.g. FMCW Lidar, frequency comb Lidar, 3D focal plane LiDAR)
• Lidar signal processing: full wave, compressive sensing, deconvolution
• Real-time and embedded electronics and programming for piloting, control and signal processing (e.g. GPUs, FPGAs)
• Laser instrument integration and demonstration outside the laboratory: stand-alone instruments, on mobile carriers on land, in the air (aircraft and drones) and in space, in underwater environments, etc.

Main scientific and technical objectives:

• Laser remote sensing instruments: 3D telemeter and imager, 3D LiDAR, Lidar televelocimeter, atmospheric Lidar (wind speed, gas concentration, aerosol characterization, temperature), Laser vibrometer
• Laser weapons and laser vulnerability
• Laser system sources and architecture: fiber lasers, hybrid architecture, coherent and incoherent laser combinations
   

Examples

BOFIX laser and Lidar LIVE For the study of air mass dynamics, a wind measurement lidar was designed incorporating a specially developed laser source. The integration of this lidar on a test aircraft demonstrated the measurement of the wind vector from an altitude of 5
km down to the ground.

Airborne Lidar LIVE. Left: 500 μJ high-energy pulse laser, center: Lidar Live installed in the ATR42, right: example of wind vector reconstruction as a function of altitude.
 

 

 

The development of the VEGA lidar, dedicated to the remote measurement of methane flow, was based on the results of two theses (P. Benoit for the laser source and S. Le Méhauté for the lidar) and on the multidisciplinary skills of the Laser Source and Lidar Systems team (laser/lidar co-design, instrument integration, signal processing). During several test campaigns, this DIAL/Doppler fibered lidar  demonstrated its performance, as well as the robustness and reliability of a fully fibered architecture.

The MATLIS software developed by ONERA simulates the performance of a laser imager, taking into account the physical  phenomena involved: characteristics of the laser source, propagation of the laser beam in the atmosphere whatever the meteorological conditions, laser-matter interaction, scene dynamics (movement of objects and dynamic aerosols) and integration of "sensor" models. MATLIS software is used upstream of any new development of 3D LiDAR systems.

Active and passive remote sensing

DOTA Pierre-Yves Foucher, Laurence Croizé (POC name.surname@onera.fr)

Scientific purposes and applications :

• Detect and quantify bio-physical-chemical variables directly or indirectly associated with human activity using multimodal remote sensing at different spatial, spectral and temporal scales.
• Characterization of human activity for defense, security and environmental purposes

Skills base:

• Remote sensing in the optical range (0.4-12.0 μm)
  - active / passive
  - high spatial resolution (cm to decameters)
  - any type of platform (ground, drone, aircraft, satellite)
  - optical/microwave complementarity
   
• Key points
  - multi-scale approach
  - validation
  - poor weather conditions
  - reducing preconceptions

Examples

Wave surface control, adaptive optics

DOTA Serge Meimon, Jean-François Sauvage. (POC name.surname@onera.fr)

Scientific and technical skills:

• Phase and amplitude measurement and imaging
• Active and adaptive optics
• Optical interferometry and multi-pupil imaging
• Automation and real-time control laws
• Characterization (modeling and measurement) of optical effects of atmospheric turbulence
• Co-phasing and beam shaping (coherent and incoherent)
• Propagation through turbulence and imaging through complex media
• Signal and image processing & artificial intelligence
• Co-design for high angular resolution instruments

Main scientific and technical objectives

• High-resolution, high-contrast imaging for space surveillance (Astronomy and SSA)
• Biomedical imaging
• Free-space optical telecommunications
• Optical metrology
• Contributions to the laser weapon, endo-atmospheric imaging, high-resolution imaging of the Earth from space, imaging through turbid and highly scattering media

Examples

 

Optical sensors and hyperspectral imagers

DOTA Guillaume Druart, Yann Ferrec. (POC name.surname@onera.fr)

Socle de compétences scientifiques et techniques :

• Study of optical components or atypical optical concepts
  multichannel architectures, bio-inspired architectures, cryogenic optics, freeform optics, graded index optics, self-imaging, lensless imaging, phase masks, kaleidoscope, plenoptic imaging, interferometric blades, birefringent blades for interferometry, PIC
• A frugal approach to miniaturizing and simplifying cameras
  SWAP-C issues, cryogenic cameras, infrared cameras for home automation or automotive applications, optical loads for nanosatellites
• Static interferometers for Fourier transform spectrometry and spectro-imaging
  hyperspectral cameras, high-speed spectrometers
• Multispectral infrared imagers with cooled or uncooled detectors
• Performance modeling of optical instruments
  radiometric models, range calculation, image simulation
• Development of characterization benches for instrument acceptance testing
  NETD, BSFR, FTM by spot scan or inclined test pattern, distortion, calibration in a fume hood
• Physical processing of images acquired from a scene,
  radiometric and spectral image processing in luminance or brightness temperature, shutterless algorithms, spectrum reconstruction from interferograms, subpixel image registration, digital elevation model, gap interferogram processing, image resampling methods
• Phase imaging
• Development of new optical system design strategies
  end-to-end approach, differential ray tracing, Simultaneous Multiple Surfaces method, artificial intelligence, construction of surfaces from the parabasal ray
• Imaging instrument integration and demonstration outside the laboratory
  stand-alone instruments, on land, air and space mobile carriers
• Line-of-sight servo-control for airborne imaging and target tracking

Examples

SIMAGAZ, the first compact cryogenic multispectral camera for gas detection, is based on cryogenic optics and specific high-performance image processing. While the application need was expressed by TotalEnergies in the course of a research-industry partnership, a preindustrial demonstrator was made possible thanks to a single interministerial fund - FUI Imagaz -, demonstrating exceptional performance in terms of quantitative visualization and temporal evolution of a methane plume.

 

The SIELETERS hyperspectral instrument is a high-performance airborne hyperspectral imager that can obtain 205 spectral images of the same scene in the infrared (from 3.0 μm to 5.4 μm and from 8.1 μm to 11.8 μm). Its spectral resolution ranges from 13 nm to 90 nm. It is based on Fourier transform static spectro-imager technology.

More details

https://www.onera.fr/en/phy-dota/aiquido-lab