Light Tec. Characterization of ultra-polished surfaces in UV and IR. ICSO October 2016 Biarritz, France

Transcription

1 ICSO October 2016 Biarritz, France Light Tec Characterization of ultra-polished surfaces in UV and IR Quentin Kuperman, Author, Technical Manager Yan Cornil, Presenter, CEO Workshop 2016, 12/09

2 Outline Introduction Light Tec presentation Photometric laboratory Scattering instruments Visible BSDF Previous work in visible range Bench setup Results UV BSDF Bench setup Results IR BSDF Specular Bench upgrade to IR range CNES campaign: Bench s performances validation in the MWIR and LWIR Gratings characterization Conclusion

3 Introduction Light Tec locations Light Tec GmbH Munich, Germany Aix en Provence, France REFLET assembling 3 employees Light Tec Sarl, Hyères, France Main office 150 m², 6 employees Training room 500 m², 12 employees Training room R&D for REFLET/Mini Photometric laboratory

4 Light Tec products Synopsys products Introduction Light Tec activities Optical Simulation Software Code V :optical design LightTools : illumination design LucidShape, LucidDrive RSOFT : waveguide, nanoptics, telecom TFCalc : thin film design Engineering Lighting Displays Optical design Scattering measurements Measurements service Instruments (REFLET, Mini-Diff)

5 Introduction Laboratory scattering instruments REFLET Benchs High Specular Bench Clean room REFLET Benchs High Specular Bench

6 Introduction Updates: Scattering measurements laboratory List of equipments 1 REFLET 90 1 REFLET REFLET 180 S MiniDiff : Blue, Green, Red, IR Integrating sphere, visible, 8 inches Integrating sphere, IR, gold, 6 inches Integrating sphere visible, 1 meter Video Photometer Spectro Radiometer nm CAS120 InstrumentSyst. Specular Scattering Bench : 3/10 meters Motorized tables Photomultipliers Source available : White light collimated beam Optical filters 350nm-1700nm every 50nm Laser stabilized :375 nm, 455 nm, 532 nm, 638, nm, 850 nm, 3.39µm, 10.6µm. Lock In Amplifier

7 Scattering measurements Laboratory scattering instruments Instruments Mini-Diff Reflet High Specular Type BRDF/BTDF BRDF/BTDF BSDF Dynamic range Wavelength range 622nm, 850nm, 940nm 400nm to 1700 nm 280nm to 10,6µm Incident angles Fixed: 0, 20, 40, 60 Tunable: +90 to -90 Tunable: 90 to 0 Angular accuracy < 2 < 0.1 < 0.01 from the specular Repeatability < 5% < 2% <2% Weight 2kg 80kg 200Kg Advantages Plug & Play Easy to use & Fast Portable & Compact Inexpensive High dynamic range High angular resolution Customisable wavelength range High precision High repeatability Very high dynamic range Very high angular resolution Customisable wavelength range High precision High repeatability

8 Visible BSDF Previous work in visible and near Infrared: BRDF configuration Bench setup : Laser sources: Wavelengths : 445nm-532nm-638nm-850nm-1064nm nm Full divergence : 0.02 Detection: photodiodes Bench configuration: 10 meters long AOI: from 0 to 90 BRDF/BTDF Sample size 1 to 5 BTDF configuration

9 ARS ARS Visible BSDF High Specular Bench : visible range Bench 1,00E+10 1,00E+09 1,00E+08 1,00E+07 1,00E+06 1,00E+05 1,00E+04 1,00E+03 1,00E+02 1,00E+01 1,00E ,00E ,00E-02 1,00E-03 1,00E-04 Scattering angle ( ) Bench ,00E+10 1,00E+09 1,00E+08 1,00E+07 1,00E+06 1,00E+05 1,00E+04 1,00E+03 1,00E+02 1,00E+01 1,00E+00 0,001 0,01 0,1 1,00E ,00E-02 1,00E-03 1,00E-04 Scattering angle ( ) High Specular Bench was developed for the visible range Length 10m Wavelengths :445nm-532nm-638nm dynamic range Resolution to a minimum angle : 0.01 (resolution of the Specular Beam profile)

10 BRDF (1/sr) Visible BSDF High Specular Bench : visible range BRDF of a 1,00E+05 1,00E ,00E+03 1,00E ,00E+01 1,00E+00 0,01 0,1 1,00E ,00E-02 1,00E-03 1,00E-04 1,00E-05 1,00E-06 Scattering angle ( ) Performances : Dynamic Resolution 0.01 from specular Accuracy <2% Min BRDF 10-6 sr -1

11 UV BSDF Bench principle: Bench setup : Laser source: Collimated LED at 280nm Full divergence : 0.02 Detection: Photodiodes Synchronous detection Bench configuration: 3 or 10 meters long AOI: from 0 to 90 BRDF/BTDF Sample size 1 to 5

12 ARS BTDF (sr-1) UV BSDF High Specular Bench : UV range 1,00E+11 1,00E+10 1,00E+09 Bench s UV 1,00E+04 1,00E+03 1,00E+08 1,00E+02 1,00E+07 1,00E ,00E+01 1,00E+05 1,00E ,00E+00 0,01 0, ,00E-01 1,00E+03 1,00E+02 1,00E ,00E-02 1,00E-03 1,00E+00 1,00E-04 1,00E-01 0,01 0, Scattering angle ( ) Performances : Dynamic Length 3 meters Accuracy <2% Resolution to a minimum angle: ,00E-05 Scattering angle ( ) Sample 1 Sample 2 Sample 3 Results : Dynamic 10 9 Angular resolution 0.02 from specular Accuracy <2% Min BRDF 10-6 sr -1

13 TIS Measurements TIS measurement in the UV and Visible range White lambertian Spectralon Optical fiber Exit port Entry port 0 Sphere characteristics Aluminum and spectraflect Size 8 3 ports (entrance-exit-8 ) Specular rejection Performances: Accuracy <0.01%

14 Scattering measurements High Specular Bench : development and upgrade to a IR range Development : New light sources New detection system New mechanical support New TIS measurement integrating sphere Integrating Sphere Spectralon Laser He-Ne 3.39µm Laser CO µm Detector

15 Scattering measurements High Specular Bench : principle Sample holder Beam Expander Laser source Detector Synchronous detection Rotating stage

16 Scattering measurements High Specular Bench : validation Measurements : about 160 BSDF Typical optical surfaces : Materials : Golden coating on silica, ZnSe coated and uncoated, uncoated Silica Source : REOSC BRDF : AOI = 10, 20, 30, polarization P and S BTDF : AOI = 0, 10, 20, 30, polarization P and S 2 Wavelengths : 3.39µm and 10.6µm IR detector : IR detector Source : ULIS BRDF : AOI =5, 10, polarization P and S Wavelength 10.6µm Infrared SIC Material : SIC Source : Airbus Defence and Space BRDF : AOI = 10, 20, 30, polarization P Wavelength : 3.39µm and 10.6µm Gratings Source : Thorlabs At Wavelength 3.39µm, Blaze 26.5, 300 grooves/mm At Wavelength 10.6µm, Blaze 27, 100 grooves/mm Polarization S/P Golden coating on Silica SIC Untreated Silica IR detector

17 ARS ARS R&T CNES Bench Signature 1,00E+07 1,00E µm 1,00E+06 1,00E+05 1,00E µm 1,00E+05 1,00E+03 1,00E+04 1,00E+02 1,00E+03 1,00E+01 1,00E+02 1,00E+01 1,00E ,00E-01 S P 1,00E ,00E ,00E-02 1,00E-03 1,00E-04 S P 1,00E-02 1,00E-05 1,00E-03 1,00E-04 Scattering angle ( ) 1,00E-06 1,00E-07 Scattering angle ( ) 3.39µm 10.6µm Dynamic range >10 9 >10 10 Beam divergence (Full Divergence) Accuracy <3% <4%

18 BRDF (1/sr) R&T CNES Infrared measurements Golden mirror on Silica at S-polarization 1,00E+06 1,00E+05 1,00E+04 1,00E+03 1,00E+02 1,00E+01 1,00E+00 0,001 0,01 0, ,00E-01 1,00E-02 1,00E-03 Bench signature ,00E-04 1,00E-05 1,00E-06 Scattering angle ( ) Performances : Dynamic 10 9 Angular resolution 0.08 Accuracy <3.7%

19 R&T CNES TIS Measurement Sphere characteristics Gold Size 6 3 ports (entrance-exit-16 ) Performances: Accuracy <1%

20 ARS R&T CNES 1,00E+06 1,00E+05 1,00E+04 MWIR and LWIR measurements ARS grating (order 1) S 3.39µm 1,00E+03 1,00E+02 Secondary peaks 1,00E+01 1,00E ,00E ,00E-02 signature ,00E-03 1,00E-04 1,00E-05 1,00E-06 Scattering angle ( ) Analysis : Dynamic : more than >less than Bench s dynamic Secondary peaks -> surface defects (scratches, digs ) The peak enlargement is due to line space irregularity

21 ARS R&T CNES ULIS detector ARS ULIS detector at 10.6µm S polarization 1,00E+06 1,00E+04 1,00E+02 1,00E ,00E-02 signature 5 1,00E-04 1,00E-06 1,00E-08 Scattering angle ( ) Dead zone Analysis : Dynamic : more than 10 9 Several orders of diffraction Specular peak enlargement -> line space s irregularity

22 R&T CNES Gratings: from the ARS to the BRDF? With the golden integrating sphere, the AOI = 8 However the intensity of the reflected beam depends on : i. The order of diffraction ii. The AOI Peaks on the ARS inaccurate measurement of the grating s efficiency We can t normalize by the TIS Value. BRDF measurement of a well-known sample rescale the measured data of the sample Getting the BRDF with a LOW ACCURACY

23 R&T CNES Specular Bench performances in the IR range Technical characteristics : Type of measurement Dynamic range >10 9 Wavelengths 3.39µm, 10.6µm Mechanical sensitivity Reading resolution Angular resolution < 0.08 Weight 500 Kg Bench stability 3.39µm : 3% 10.6µm : 3.7% ARS/BRDF/BTDF Measurement environement : Temperature 1 variation Humidity <50%RH Cleanness ISO 8 (Class )

24 Clean Room Since July 2016, a clean room was installed in the Lab ISO 5 (class 100) Painted in black to reduce stray light Clean room Specular Bench The laboratory is controlled in : Temperature : 1 variation Humidity : <50% RH Samples unpacked in the clean room : ISO 5

25 Conclusion BSDF characterization : Samples: high specular samples Grating s characterization Wavelength: From 280nm to 10.6µm Reading resolution : Resolution: 0.02 visible and UV, 0.08 IR Accuracy : <4% accuracy Min BRDF : typical sr -1 Under investigation Gratings in Littrow configuration BSDF of curved optics

26 Conclusion Thank you for your attention! Please visit us Light Tec