Lighting research Toulouse team (France) Ludovic VANQUIN Ikbal MARGHAD Lydie AREXIS BOISSON

Transcription

1 1 Lighting research Toulouse team (France) Ludovic VANQUIN Ikbal MARGHAD Lydie AREXIS BOISSON

2 Plan 2 INTRODUCTION I. Medical Imaging for the diagnosis of the Alzheimer s disease (Ludovic) II.Lighting display: Organic LED technology (Ikbal) III.Light and vision research Flickering (Lydie) CONCLUSION

3 INTRODUCTION 3 10 Departments 90 Research Laboratories 28,000 Students 2,200 Teaching & Research staff 1,250 Administrative & Technical staff Pharmacy 318 research units 52 clinical investigation centers 12 population health and clinical research networks 59 federative research institutes 8,000 Inserm employees 3,000 members of university hospital personnel 1,450 foreign research scientists Medicine Sport & Languages Sciences Natural Sciences Physics Mathematics Computer Science Civil Engineering

4 4 I-Medical Imaging for the diagnosis of the Alzheimer s disease

5 I-Medical Imaging for the diagnosis of the Alzheimer s disease 1/6 5 Positron emission tomography (PET) Nuclear medical imaging technique Use of radioactive tracers introduced into the body Magnetic Resonance Imaging (MRI) Used in radiology to visualize internal structures of the body Use of the property of nuclear magnetic resonance of water molecules to make pictures of organs and structures of the body

6 I-Medical Imaging for the diagnosis of the Alzheimer s disease 2/6 6 Optical Imaging (fluorescence imaging) Imaging modility using light to obtain information on tissue composition and biomolecular processes in the living body Fluorescent molecules that emit light when activated by an external light source (ex : laser) Interest for the diagnosis of Alzheimer s disease Alzheimer's disease is characterized by the accumulation of β-amyloid peptides, which form senile plaques in the brain : Use near infrared fluorescent agent for specific plaque targeting Use fluorescence optical imaging to localize senile plaques Enable definitive preclinical diagnosis of Alzheimer's disease

7 I-Medical Imaging for the diagnosis of the Alzheimer s disease 3/6 J.Skoch, A.Dunn, B.T. Hyman, B.J. Bacskai, Development of an optical approach for noninvasive imaging of Alzheimer s disease pathology, Journal of Biomedical Optics 10(1) (2005); Subjects and methods: Transgenic and normal mouse brains fluorescent agents : BAM-10 conjugated Alexa Fluor 750 ICG (indocyanine Green) + Thioflavin S Laser Scanning Microscope: excitation 750 nm laser fluorescence detected by an avalanche photodiode NIR microscopy of labeled plaques in mouse tissue

8 I-Medical Imaging for the diagnosis of the Alzheimer s disease 4/6 8 LI-COR Odyssey : NIR Imaging system hole brain imaging (in vivo and ex vivo) high resolution (21 micrometer/pixel) laser diodes 780-nm excitation /800-nm emission Tissue sections were cut from a transgenic mouse brain. Sections were stained with the NIR fluorescent compound ICG followed by thioflavin S

9 I-Medical Imaging for the diagnosis of the Alzheimer s disease 5/6 9 explore Optix Imaging: NIR Imaging system hole brain imaging 0.5-mm resolution Pulsed diode laser at 750 nm Tissue sections were cut from mouse brains. Sections were stained with the the fluorescent agent (Alexa Fluor 750-labeled BAM-10 antibody) Left brain : transgenic mouse Right brain : agematched nontransgenic control

10 I-Medical Imaging for the diagnosis of the Alzheimer s disease 6/6 Conclusion and prospects: 10 Fluorescence from within a whole mouse brain can be measured quantitatively with near infrared laser scanning devices These images illustrate the potential for noninvasive, whole animal detection of specifically labeled plaques in the brains of mouse models of Alzheimer s disease using optical fluorescent imaging Non invasive applications for the diagnosis of Alzheimer s disease in human patients

11 11 II- Lighting display: OLED technology (Organic Light-Emitting Diode )

12 II- Lighting display: Organic LED technology 1/5 12 Principle: OLED: Organic Light-Emitting Diode 1) Charge Injection 2) Charge transport 3) Charge combination Structure : ETL: Electron transport Layer EML:Emissive Layer HTL:Hole transport Layer HIL: Hole injection Layer Advantages: Low consumption of power Could be: transparent, flexible, Stretchable (new application) Very thin, wider viewing angles, improved brightness Holst center

13 II- Lighting display: Organic LED technology 2/5 OLED displays in automobiles 13 Integrating OLEDs with electronic textile Multimedia displays Samsung's prototype of smartphone OLED challenges Holst center My PhD research: Synthesis of molecules Their incorporation within OLED Characterization of the OLED device

14 II- Lighting display: Organic LED technology 3/5 OLED process: 14 Substrate cleaning Preparating figure Deposition layer Encapsulation R R N N N N R R Small molecule Metal-organic complexe PPV Polymer

15 II- Lighting display: Organic LED technology 4/5 15 What is responsible for the luminescence? -Luminescence: Fluorescent/ Phosphorescent -Color:.RGB.Combination :WOLED HTL EML ETL OSRAM Press Release April 2008

16 II- Lighting display: Organic LED technology 5/5 16 Summary -OLED is a thin, efficient and bright display. -OLED technology has great potential and a very wide range of applications. -Perspectives: the price and lifetime. -OLED s display are a reality, lighting to come (with WOLED)

17 17 III- Light and vision research Flickering

18 III- Light and vision research Flickering 1/6 18 Subject : «Study and optimization of energy efficient lighting and adapted to the needs of its users (health, safety and quality of life) Pluridisciplinary subject : Light sources (photometry colorimetry) Optics Physiology Neurophysiologie Cognitive psychology Visual comfort Sociology Figure 1 : modelization of an ammetropic human eye with ZEMAX-SE

19 III- Light and vision research Flickering 2/6 19 Experiments on light flickering visual perception Flickering : light vibration temporal contrast conscious or unconscious perception Critical Fusion Frequency (CFF): limit of perception Health impact: Discomfort Headaches Decrease in visual performance Photosensitive epileptic seizures Objective: To find a lighting using consuming less energy and allowing a good visual quality by limiting discomfort system.

20 III- Light and vision research Flickering 3/6 A> Expérimental Protocol on flickering perception Technical parameters : A black box in a dark room Different color background 20 Indirect and diffused light (never perceived directly) Figure 2 : Experimental scheme Flickering created by : frequency duty cycle changes (new parameter) LEDs controled by electronic boxes and software Recording responses by Push Button

21 III- Light and vision research Flickering 4/6 21 Power regulation average illuminance regulation Human parameters : 25 observers/test Age : between 20 and 40 years old Emmetropia vision or with optical correction First studies on central vision ( diract angle with the fovéa) The question : Figure 3 : transmitted signal with power control :L=f(t) Do you perceive a light vibration? Proper to the individual feels Like

22 III- Light and vision research Flickering 5/6 B> First results : 22 For the white an dark backgroung : FFC : 65Hz Same kind of curves more frequencies increase and less flickering is perceived Impact of duty cycle on the same frequency perception More the duty cycle is little more it is perceived (higher temporal contrast) White background : more categorical perception Larger range of perception higher visual fatigue Influence by the scenarii order Increased detection performance with time Figure 4 : Results withc a) dark background b) white background

23 III- Light and vision research Flickering 6/6 23 C> Other flickering experiments realised : Study on higher ranges of frequencies (untill 100Hz) Study on the time influence on the response Order scenarii study Flicker experiments with color backgrounds : Red Green Blue Study in peripheral vision (90 and 45 ) Application : flickering for museum light de musée (Color degradation of paints) cf. FFC et sensation de brillance plus élevée en en lumière pulsé.

24 CONCLUSION 24 To learn more things about : Radiometry and photometry light and health impact indoor and outdoor specific light applications : lighting technologies and softwares lighting displays such as LED.

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