1. Designing with Tertiary Optics
in Mind
Suleyman Turgut
Luminit

2. Agenda
 LED Optics Terminology
 Examples of Designs
 Design Concept: “Collimate then Diffuse”
 Benefits
 Formats
 Holographic Diffusers
 Modeling Tools
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3. Terminology
 Primary Optic – ball lens on LED (90-110º)
 Secondary Optic – TIR or Reflector (5-15º)
 Tertiary Optic – Diffusers (5-80º)
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4. Example: PAR38
 Primary Optic
 Secondary Optic
 Internal Reflector
 Fresnel Lens
 Tertiary Optic
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5. Example: Recessed Down Light
 Primary Optic
 Secondary Optic
 Internal Reflector
 Tertiary Optic
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6. “Collimate then Diffuse”
• Bare LED Radiation Pattern
– Directional but still very wide, 90-110º beam angle
– Not useful or efficient if your “throw” is > 0.5 meter
• Secondary Optics
– Collimates the beam angle to 5-15º
• Tertiary Optics
– Expands the beam to the required beam angle and shape
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7. Benefits of “Collimate then Diffuse”
• Single Optical System Design
– No need to redesign secondary optical system if the project/product
requires a different beam angle
• Reduced Total Cost and Faster Time to Market
– Single mold cost for secondary optic
– Fewer SKUs
• Flexibility
– Same fixture can address different projects
– Diffuser accessory can allow the beam angle to be changed in the field
• Cleaner Target Plane
– Reduced hot spots, better color uniformity, reduced multiple shadows
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8. Example: Single Optical System Design

9. Example: Single Optical System Design

10. Example: Single Optical System Design

11. Example: Reduced Total Cost
Required: 3 Different Angles
• 3 Optical Designs • 1 Optical Design
• 3 Molds • 1 Mold
• 3 SKUs • 1 SKU
• Larger Inventory • 3 Accessory Lenses

12. Example: Cleaner Target Plane

13. Example: Cleaner Target Plane

14. Example: Cleaner Target Plane

15. Tertiary Optics: Formats and Options
Thin Films
 Substrate: 0.25mm thick PC
 Sheets or Rolls up to 20” Wide
 Cut parts
 Strip Rolls 250 feet long
Thick Substrates
 Substrate: 3mm thick PC
 UV stable (non-yellowing)
 Up to 20x40” sizes
Injection Molded
 Substrate: UL flame rated
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16. Surface Relief vs. Bulk Diffusers
• Surface Relief Pattern
 High transmission efficiency:
~92%
800  Optical performance is
independent of thickness of
substrate
• Random Size Distribution
 Ensures uniform optical
performance over all
wavelengths/colors

17. Modeling/Simulation
• BTDF data available on our website
• Surface Diffusers can be modeled in:
• Photopia (http://www.ltioptics.com)
• LightTools (http://www.opticalres.com)
• TracePro, Optis and Zemax

18. Thank you.