Valter Drazic

Principal Scientist

Immersive Lab Researchers

I have always had the desire to build a big picture of the world and understand how things work, that was the reason why I studied physics. 
Optics was a natural move since the modern physics built upon discoveries made by early scientist about the nature of the light. 
It has been very natural to orient my career about "light shaping" technologies: Lens design, illumination systems, spatial light modulation (displays), colorimetry.
As one of my dearest hobby is photography, I had at the same time a big appeal towards images, which are the practical visualization of the shaping that light undergoes when it interacts with the real world.
From the alliance of both passion for light and images, I developped skills in image acquisition systems, computer vision, 3D systems and processing. I am not an expert in software development, but I was facinated
by the power of GPGPU when applied to the calculation of disparity maps and interpolated images in stereovision systems. One of my dearest achievement, maybe because it was not my field, is a real-time disparity estimator written in CUDA and OpenCL, which ranks as the most precise real-time estimator.

I also discovered some unforseen solutions to common problems, which ended into:

• 36 Granted Patents in the fields of displays (LCD, OLED, DLP, Plasma) and cameras, illumination systems, lens design, computer vision, lightfield acquisition, HDR, colorimetry, GPU algorithms for disparity estimation.

• 75 pending applications (dec. 2017)

• 33 filed patents in 2016: most prolific inventor worldwide for the topic “lightfield for mobiles”
 

PRINCIPAL SCIENTIST (2012-2018)

Light-guiding project

  • Investigation of wavelength size structures for the generation of dense photonic jets in the near field. With application to:
    • Light extraction from OLED displays.
    • Disruptive pixel architecture for image sensors
    • New optical components for AR type Head Mounted Displays

Lightfield Technologies project

  • Invented a new file format for Light-field data:
    • Agnostic to acquisition systems.
    • Ray based in the object space.
  • Invented an extended pinhole camera model for thick lens systems.

Leading of several exploratory projects

  • Plenoptic Super Resolution
    • Coaching of 2 interns and a post doctoral position.
    • State of the art de-mosaicking and depth calculation.
    • New ways of processing plenoptic data led to state of the art view rendering.
  • Light-field sensor
    • Aberration corrections.
    • Field of view extension of plenoptic cameras.

One of the exploratory projects successfully transferred into a new group project on Lightfield technologies.
 

Demos and talks

  • Demo of real-time fusion rig at Technicolor Science & Technology (S&T) annual meeting ’13.
  • Demo on image refocusing on a tablet and plenoptic signal processing at S&T meeting ’14.
  • Talk on computational photography at S&T meeting ’13.
  • Presentation of Light-field acquisition at S&T meeting ’14.
  • Lab presentation on Optics for Augmented Reality glasses ’17.

Real-time Disparity estimator on GPU

  • Development of a Real-Time Disparity estimator on GPU. Breakthrough for speed-precision.
  • Numerous participations to demonstrations in the field of real time estimations, real-time image interpolation for 3D workflows, including on streaming content.
  • The estimator is cited in “Multi-view Acquisition and Advanced Depth Map Processing Techniques”, a chapter from “3D Future Internet Media” book.
     

SENIOR SCIENTIST. (Before 2012)

European FP7 project OSIRIS, Work Package Leader for Video lightfield camera.

Thomson Research & Innovation, 3D Content and Acquisition Lab, Rennes, France.

  • Management of the 3D content acquisition in the frame of the EU OSIRIS project.
  • Development of the first worldwide video plenoptic camera. (Lab camera).
     

TECHNICAL EXPERT, OPTICS FOR DISPLAYS.

Thomson Research & Innovation, Displays Lab, Rennes, France.

  • Prototype design of a 50" DLP rear projector illuminated by LEDs, private show at IFA-Berlin 2005.
  • Prototype design of a Slim DLP rear projector, presented at the CES-Las Vegas, 2005.
  • Doubling of the light efficiency of an organic LED (OLED). Collaboration with the CEA at Orsay.

Thomson, TV/Video Business Unit, Indianapolis, USA.

  • Development of the very first three-LCOS rear projector product. Commercialized product.
  • Assigned in the USA as the coordinator between the research and the business unit.
     

R & D ENGINEER IN OPTICS AND PROJECT LEADER FROM 97.

Thomson R & D, Displays Lab in Strasbourg (93-96) and Rennes (96-01), France.

  • Stray light analysis in a CRT rear projector for Thomson Indianapolis.
  • Simulation of the light efficiency of a plasma screen for Thomson Plasma, Grenoble.
  • Development of innovative illumination systems for microdisplays.
     

PhD thesis

  • Fonctions de transfert optique tridimensionnelles et critère de confocalité pour le microscope à balayage. Verlag Shaker, Aachen, Germany, 1993.

JOURNALS

  1. Dependence of two- and three-dimensional optical transfer functions on pinhole radius in a coherent confocal microscope. V. Drazic. Journal of the Optical Society of America A, 9(5) :725-731, 1993.
  2. Dependence of two- and three-dimensional optical transfer functions on pinhole radius in a coherent confocal microscope – reply to comments. V. Drazic. Journal of the Optical Society of America A, 10(3) :535-537, 1993.
  3. Three-dimensional transfer function of coherent confocal microscopes with extended source and detector. V. Drazic. Journal of Modern Optics, 39(8):1777-1790, 1992.
  4. Three-dimensional transfer function analysis of a coherent fluorescence microscope with finite sized source and detector. V. Drazic. Journal of Modern Optics, 40(5):879-887, 1993.
  5. Optimal design and critical analysis of a high resolution video plenoptic demonstrator. Extended paper published in the Journal of Electronic Imaging, Q1/2012 as one of the best papers from SDA 2011
  6. An Image Rendering Pipeline for Focused Plenoptic Cameras, M. Hog, N. Sabater, B. Vandame, V. Drazic, IEEE Transaction of Computational Imaging. May 2016.
     

CONFERENCES

  • Optimal depth resolution in plenoptic imaging, V. Drazic, ICME 2010 Singapore, July 2010
  • Optimal design and critical analysis of a high resolution video plenoptic demonstrator. V. Drazic & al, Stereoscopic Displays and Applications, San Francisco 2011
  • A precise Real-time Stereo Algorithm, V. Drazic and N. Sabater, IVCNZ 2012, Dunedin, New Zealand
  • A real-time 3D multi-view rendering from a real-time 3D capture, D. Doyen, S. Thiebaud, V. Drazic, C. Thébault, SID 2013
  • Light-Field Demultiplexing and Disparity Estimation, N. Sabater V. Drazic M. Seifi G. Sandri, P. Perez, ICCP 2014
  • Fusion of Kinect depth data with trifocal disparity estimation for near real-time high quality depth maps generation, G. Boisson, P. Kerbiriou, V. Drazic, O. Bureller, N. Sabater, A. Schubert, SDA 2014
  • Accurate Disparity Estimation for Plenoptic Images, N. Sabater, M. Seifi, V. Drazic, G. Sandri, P. Perez, Computer Vision ECCV 2014 Workshop.
  • Light-Field Demultiplexing and Disparity Estimation, N. Sabater, V. Drazic, M. Seifi, G. Sandri, P. Perez, ICCP 2014.
  • Disparity Guided Demosaicking of light field images, M. Seifi, N. Sabater, V. Drazic, P. Perez, ICIP 2014.
  • On Plenoptic sub-aperture view recovery, M. Seifi, N. Sabater, V. Drazic, P. Perez, EUSIPCO 2016.
  • Camera-agnostic format and processing for light-field data, M. Damghanian, P. Kerbiriou, V. Drazic, D. Doyen, L. Blondé, ICME 2017.
  • Near field focusing by edge diffraction, A. Boriskin, V. Drazic, R. Keating, M. Damghanian, O. Shramkova, L. Blondé, Nature Photonics 2018 submission.
  • Plenoptic sensor: application to extend field-of-view, B. Vandame, V. Drazic, M. Hog, N. Sabater, ICCP 2018 submission.
     

GRANTED PATENTS

Optical components

  1. Reflecting light polarizer made of coated non-linear surfaces, US6775061B2

Oled

  1. Organic Light-emitting diode with relief patterns, US7733011B2, EP1766703A1
  2. Electroluminescent panel provided with light extraction elements, EP1654773A2

Backlighting

  1. Colour display device with backlighting unit using organic light-emitting diodes and method of implementation, US8106876B2

Projection displays

  1. Projection image display device having two modulation stages including one aperture modulation stage, US8231228B2
  2. Simplified polarization recovery system, CN1918490B
  3. Polarized light illumination device, US7180666B2
  4. Large screen digital projector, US7794092B2
  5. High contrast stereoscopic projection system, US7192139B2
  6. Optical system and corresponding optical element, US7940464B2
  7. Compact polarization recovery system for illuminating LCOS and LCD based systems, Granted CN ZL02823564.9, feb. 2008
  8. Optical polarization device and projection system of liquid crystal valve type utilizing such a device, US5900973
  9. System for projecting or displaying images, US6593996B2
  10. Illumination device with light reshaping element for an optical valve, US6312143
  11. Imager to imager relay lens system, US7317578B2
  12. Image projection or display system, EP1354241A1
  13. Peak brightness improvement for LC/DLP based RPTV, US6837584B2
  14. Polarisation converter system for a liquid crystal projector, EP1529237B1
  15. Projection display apparatus, US7300158B2
  16. Stereoscopic image projection system, US7204592B2
  17. Two-stage projection architecture, US7175279B2
  18. Multiple lamp illumination system with polarization recovery and integration, US7717578B2
  19. Two-stage projector architecture, US7431460B2

3D-Stereoscopy

  1. Method and device for inserting a 3D graphics animation in a 3D stereo content, US9685006B2
  2. Anagylphic stereoscopic image capture device, US9247233B2

Acquisition

  1. Multi-image capture system with improved depth image resolution, US8111320B2
  2. Method for obtaining at least one high dynamic range image and corresponding computer program product and electronic device, US9811890B2
  3. Device for estimating the depth of elements of a 3D scene, EP2535681B1

Lightfields

  1. Plenoptic camera comprising a shuffled color filter array, US9807368B2
  2. Method and apparatus for estimating depth of focused plenoptic data, US9818199B2
  3. Plenoptic camera comprising a light emitting device, US9691149B2

Head Monted displays

  1. Optical see-through glass type display device and corresponding optical element, US9846302B2

Depth Estimation

  1. Method and apparatus for disparity estimation, US9704252B2
  2. Method and device for providing temporally consistent disparity estimations, US9113142B2
  3. Method and device for estimating disparity associated with views of a scene acquired with a plenoptic camera, EP2879092A1
  4. Method and apparatus for performing depth estimation, US9600889B2
     

EDUCATION

PhD, 3D Optical Transfer Functions in Optical Microscopy (1993)
Karlsruhe Institute of Technology, Germany.

Master of Science in Photonics.(1989)
University Louis Pasteur, Strasbourg, France.

Master of Science in Optical engineering. (1988)
Ecole Nationale Supérieure de Physique de Strasbourg, France.