high and low refractive index coatings for optics
TRANSCRIPT
OPTICS FOR ALL-WEBINAR (APRIL 14, 2021)
HIGH AND LOW REFRACTIVE INDEX COATINGS FOR OPTICS
Jukka Perento, Inkron Oy
CONFIDENTIAL
TOPICS
Introduction
Portfolio for Optics
Nano-imprint lithography
Application and device level examples
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INKRON, SPECIALIST IN SILOXANE CHEMISTRY
INKRON – A NAGASE GROUP COMPANY
• R&D and manufacturing in Espoo, Finland. Opto-packaging team in Taiwan.
NAGASE AND NAGASE CHEMTEX
• Headquartered in Tokyo Japan. Related business manufacturing in Harima, Japan; Wuxi, China; and Ohio, USA.
• 7,200+ employees, global operations and annual turnover ca. US$8bn.
Japan
Taiwan
Finland
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LED PACKAGING
CONFIDENTIAL 4
• Die attach adhesives
• LED encapsulants
OPTICAL DEVICES
• Light management coatings
• Nano-imprint lithography, DOE
• High and low refractive index
TYPICAL MARKETS
PRINTED ELECTRONICS
• Printable inks
• Screen print, inkjet
• Structural adhesives
MATERIALS FOR OPTICS
CONFIDENTIAL 5
HIGH RI NIL COATINGS
CONFIDENTIAL 6
• RI range 1.55-1.9x
• Optically clear
• NIL processable
• Matching adhesion promoter
EDGE BLACKENING
• High RI (range 1.55-1.9x)
• High Optical density (OD)
• RI matched with the substrate
• Even 96 % reduction of backscatter (compared with “standard” black)
ESSENTIAL SOLUTIONS FOR AR, DOE AND OPTICS
LOW RI COATINGS
• Low RI, range 1.1-1.4
• Antireflection VIS/IR
• Gap filling, cladding layer
• Optically clear
IN SEARCH OF RIGHT REFRACTIVE INDEX COATING
n = 1.5 – 1.9x
Optical Coatings and NIL
n = 1.4 - 1.7
Optical Bonding
n = 1.1 - 1.4
Optical Coatings and Gap Fill
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HIGH RI NIL COATINGS’ OPTICAL PERFORMANCE
IOC n = 1.7 on glass*
IOC n = 1.8 on glass*
IOC n = 1.9 on glass*
IOC n = 1.8 on subst. corrected film transmission
IOC n = 1.9; Abbe = 17
IOC n = 1.8; Abbe = 19
IOC n = 1.7; Abbe = 36
*) Each measurement done with n matching Schott
RealView glass substrate
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CONFIDENTIAL 9
INKRON’S NIL FACILITY
NIL COATINGS’ IMPRINT PERFORMANCE
*Slanted grating master manufactured and provided by NIL Technology AsP.
• IOC with n = 1.7 – 1.92 shows great pattern fidelity in various stamp shapes and aspect ratios • Line/space gratings with linewidths down to 75nm with aspect ratio >3.5; Bi-directional 30° slanted
gratings with 400nm vertical height; Various pillar patterns (also non-spherical).
~ 50 nm residual layer
IOC 172 (n = 1.7) IOC 132 (n = 1.8) IOC 133 (n = 1.9)
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OPTICAL BLACK MATERIAL
1. Minimize the reflection at the edge of the glass by refractive index matching between the glass and optical black material.
2. Minimize light re-entering from the optical black coating to the high RI glass by having high absorbance black optical coating (high optical density, OD).
3. Minimized re-entering due to the scattering.
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OPTICAL BLACK AT LENS EDGE
96% decrease in reflectance when RI of the IOB coating is matched with the
glass wafer (n=1.9)
• Edge reflectance (%) drops from 10% to 1% with optical black coating • … and 96% (from 1% to 0.04%) with black coating n-value optimization• OD up to 5 with 25 um film thickness
Light reflectance on (n = 1.9) glass lens edge without and compared with different Inkron’s index of refraction optically black
coatings
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• Lens wafer to cover-lens stacking
LENS & HIGH/LOW-N STACKING
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Glass
GlassIAP-110 primer
IOC-133 RI 1.9
IBA-210 RI 1.4
Δn = 0.5 @589nm
Alternating:IOC n=2.05; 30nmIOC n=1.25; 130nm
• High – low refractive index layer stacking
Δn = 0.8 @589nm
GAP FILLING
APPLICATION EXAMPLES OF LOW RI COATINGS
CONFIDENTIAL 14
ANTIREFLECTION COATINGS
CLADDING LAYERS
• Particle free low RI, No haze or scatter
• Antireflection in VIS/IR
• Light guide optimization REFLECTED
PASSED
CLADDING
LIGHT- GUIDE
NO CLADDING
AR coating in visible area
AR coating in IR area
DEVICE LEVEL EXAMPLES
CONFIDENTIAL 15
3D SENSOR: TIME-OF-FLIGHT SENSOR
APPLICATION EXAMPLES
CONFIDENTIAL 16
• Sends a photon to the object, measures the return time of reflected light -> 3D depth map of the object
3D SENSOR: STRUCTURED LIGHT SENSOR
• Illuminates a known pattern on an object
• Pattern deformation used to calculate distance
AR GLASSES
• Waveguide (diffractive optics) for AR/XR glasses
DISPELIX AR GLASS DEMO
3D SENSORS
OTHER APPLICATIONS OF (DIFFRACTIVE) OPTICS
