Presentation given by David Scott-Maxwell, R&D Manager at Forge Europa, describing the various engineering disciplines needed for the development of a high quality LED based lighting product.

1. Design Considerations for Effective LED Integration David Scott-Maxwell R&D Manager Forge Europa Visible Solutions

2. Or…

3. Designing LED Lights is EASY …

4. … to Get WRONG ! … Designing LED Lights is EASY …

5. How Easy?

6. How Easy? An everyday example: 24 LEDs in a magnetic clip light Powered by 3 AAA batteries Cost £4.99

7. How Easy? L70 ~1hr !

8. How Easy? You can buy candles that last longer than this for the same money and give out the same light for 14 days continuously!

9. So How do we Get it Right ?

10. So How do we Get it Right ?

11. We have to wear many different hats!

12. LED Expert LED EXPERT

13. Cost {-per Lm / -per Cd / -per LED …} Availability {can you really buy what you want? …} Luminous efficiency {Lm/electricalW / Lm/opticW …} Light extraction efficiency {beam shape, size, uniformity …} Manufacturability {SMT reflowable, handling …} Physical size {lots of choice!} Light power rating {efficiency, eye safety …} Colour {range, colour rendering …} Reliability {MTBF, L70 …} Viewing angle {integral lenses, circular/elliptical …} Multi sourcing {desirable if possible …} Patents {hot issue! …} … LED EXPERT LED Expert

14. OPTICS Engineer OPTICS ENGINEER

15. LED EXPERT OPTICS Engineer Transmissive optics (lenses etc) Cost Material choice {PC, PMMA …} Transmission efficiency {big concern …} Type {within-LED, separate, standard, bespoke …} Manufacturability {mounting, handling …} Beam pattern quality {colour stability, colour mixing …} Diffusion {prismatic, random …} Reflective optics (reflectors!) Growth area ? GLARE

16. ELECTRONICS Engineer ELECTRONICS ENGINEER

17. LED EXPERT ELECTRONICS Engineer CONSTANT CURRENT! Passive Current Control {resistors …} Active Current Control {linear, switched mode …} Low vs High Voltage AC / DC Power factor correction Dimming / modulation LED protection Topology series / parallel LED junction temperature … all affect: Cost Efficiency Electromagnetic compatibility Reliability Intellectual property …

18. THERMAL Engineer THERMAL ENGINEER

19. LED EXPERT THERMAL Engineer LED temperature CRITICALLY controls: LED lifetime LED efficiency There’s only one place for heat to go – into the environment by: Conduction {to body of product, via water …} Convection {heatsinks …} Radiation {from body of product …} How to move heat: PCB {Metal core, FR4, exotic …} Thermal I/F {gap fillers, greases, phase change materials …} Heatsinks {standard, bespoke …} Enclosure {use product body itself …} Exotics …

20. Chemist CHEMIST

21. LEDs are NOT chemically inert! Sealed LEDs => reliability problems Unsealed LEDs => oxidation problems LED silicone encapsulants can react with: Adhesives Cleaning agents Sealants Mould release agents … Conformal coatings – LED compatible? LED EXPERT Chemist

22. PRODUCTION Engineer PRODUCTION ENGINEER

23. LED “bin” grading {colour, brightness, voltage …} Production bin management {segregate, dither …} Binning standards {harmony may be emerging? …} ESD hazards {handling …} Mechanical issues {SMT handling, humidity …} Packaging {lens integrity …} Test {what/how?, eye safety …} … LED EXPERT PRODUCTION Engineer

24. TEST Engineer TEST ENGINEER

25. Test/measurement during DESIGN of: Optics {photometer, goniometer, spectrometer …} Electronics {efficiency, EMC …} Environmental {temperature, humidity, vibration …} LED Tj {LED pn junction temperature …} Test/measurement during MANUFACTURING of: Some of the above … LIFE TEST is very important as LED technology is moving so fast … LED EXPERT TEST Engineer

26. Don’t Worry! LED EXPERT

27. To design high quality LED lighting products you need to wear many different hats… Don’t Worry! LED EXPERT

28. To design high quality LED lighting products you need to wear many different hats… Don’t Worry! LED EXPERT LED EXPERT OPTICS ENGINEER ELECTRONICS ENGINEER THERMAL ENGINEER CHEMIST PRODUCTION ENGINEER TEST ENGINEER

29. You don’t need to be a magician to design high quality LED products… LED EXPERT Don’t Worry!

30. You don’t need to be a magician to design high quality LED products… But you do need to understand many disparate disciplines … LED EXPERT Don’t Worry!

31. You don’t need to be a magician to design high quality LED products… But you do need to understand many disparate disciplines … Or – Choose a partner with these skills! LED EXPERT Don’t Worry!

32. To find out more about how Forge Europa can help you design and manufacture high quality, reliable and energy efficient LED lighting products, contact us on +44 (0)1229 580000 or e-mail [email_address] LED EXPERT www.forge-europa.co.uk Why not sign up to receive our newsletter?