english SHOP NEWSLETTER CONTACT COMPARISON HOME KNOW-HOW SUPRAX 8488 COMPARISON OF MATERIALS SUPRAX 8488 Comparison of Materials Temperature Stability Solarization Stability Microwave Characteristics SNAP IT Handling Fresnel Lenses Other Materials Coating Optical R&D Papers LONGLASSTING As one of the world's most experienced designer and manufacturer of optical glass components for the lighting industry, Auer Lighting highly recommends glass for LEDs. This is due to its features concerning environmental resistivity, transparency and the ability to withstand temperatures well above 300 °C without degradation. In particular, the last point is becoming of increasing interest as the power of LEDs is rising and thus producing more heat. Optics made from plastic materials will only stay stable for much lower temperatures, limiting already the potential performance of high-power lighting systems. The advantages of glass open up the possibility to use more powerful light sources that bring LED lighting to a whole new brightness level. PROPERTIES OF OPTICAL MATERIALS Property Glass SUPRAX 8488 PMMA PC Silicone Remarks Density (g/cm³) 2.31 1.18 1.20 1.02 Water absorption (weight %) no 0.6 - 2.0 0.1 - 0.3 0.2 acc. to ISO 62 Thermal expansion coefficient (10-6/K) 4.1 80 70 250 - 345 Thermal conductivity λ (W/(m K)) 1.20 0.19 0.21 0.31 Heat capacity (J/(g K)) 0.80 1.20 1.17 1.37 @ 25 °C Flammability (mm/min) (class) no 25 (HB) 2.5 (VO) HB-V1 UL 94 Chemical resistivity ++ - 0 + Short-time operating temperature (°C) 450 93 130 260 Permanent operating temperature (°C) 400 <80 <110 150 Light transmission (%) 92 92 89 91 D = 3 mm Refractive Index nd 1.482 1.492 1.585 1.410 @ 25 °C Fresnel losses (%) 3.8 7.5 3.9 7.6 5.1 9.9 2.9 5.7 one surface two surfaces Thermo-optic coefficient dn/dT (10-4/K) ∼0 -1.1 -1.1 -5.0 Abbe number 65 59 31 50 νd Coatability ++ 0 0 - UV resistivity ++ 0 - + Cleanability ++ - - - Possible feature size 0 + + + Yellowness index 0 8 9 1 30 years ASTM E313 GLASS - THE PERFECT COMPANION FOR LONG-LASTING LEDS Glass is the perfect companion for long-lasting LEDs, due to its durability as well as versatility in shape and features. And temperature is no problem for glass. It can be easily coated (to enhance initial performance) and cleaned (to keep that initial performance). From the cost side glass optics can reach competitive pricing levels if adequate design is accounted for, especially for specialized and/or qualitative optics. A simple copy of existing plastic optics will not do so. Why glass has been put in second place so far in the LED world is not easily understandable. But it shows so many valuable and interesting features that no one can afford to ignore it any longer. CONTACT Auer Lighting GmbH Hildesheimer Straße 35 37581 Bad Gandersheim Germany Phone: +49 5382 701 · 0 Fax: +49 5382 701 · 297 info@auer-lighting.com NEWSLETTER Subscribe to our newsletter to stay up-to-date with our latest innovations. REGISTER FOR FREE INFORMATION Downloads Terms Imprint Privacy Cookie Settings This website uses cookies! We use cookies. Some of them are necessary to make the website usable. Others help us display information that is relevant and engaging to you. As data protection is important to us, we ask you to decide on the scope of use. You can either accept all cookies or choose your individual settings. Thanks and enjoy our website! Accept all Accept only essential cookies Advanced cookie settings Privacy Imprint Individual cookie settings This is an overview of all cookies used on this website. Please make your individual settings. You can adapt them at any time by using the "Cookie settings" link in the footer of this website. ACCEPT ALL ACCEPT ONLY ESSENTIAL COOKIES SAVE SETTINGS Back Essential (1) These cookies are essential to the operation of the website, e.g. by saving your cookie settings. Show details Analytics (2) Tools collecting usage data anonymoulsy, giving insights into how to improve our services for you. Show details External media (3) Tools enhancing the browsing exerience, e.g. maps or videos. Show details Privacy Imprint