news digest ♦ LEDs
Tsui, VP of Reliability Engineering Department of IST.
Tsui further explains that LM-80 is required by US Energy Star and involves the collection of data based on 3 different case temperatures for over at least 6000 hours. The lumen maintenance requirement is also needed. This test will provide standardised quality assurance and quality certification for lighting fixture manufacturers and LED manufacturers respectively.
SemiLEDs CEO, Trung Doan adds that S35 and P2, warm and cool white (5700K and 3000K respectively) were our the series to go through the 6000 hour tests at both 350 and 700mA.
The test result from IST showed that the lumen maintenance is 98.75% and 97.81% for 55℃and 85℃, respectively, for 3000K emitter at 700mA driving current, far above the requirements of LM- 80 for domestic indoor application at 91.8% and domestic outdoor and commercial usage at 94.1%.
SemiLEDs further explains that providing high quality components to lighting fixture manufacturers is important in enabling quicker penetration of LED into the lighting market.
The S35 is SemiLEDs first series of emitters with a 35x35mm footprint utilising a silicon housing material. SemiLEDs had launched the C35 – the second generation of its 35 x 35mm emitters in June 2012. The C35 incorporates SemiLEDs EV LED chip and a ceramic base.
The thermal resistance complements SemiLEDs vertical chip on metal alloy substrate technology. Besides thermal management, SemiLEDs also implemented the latest innovation in phosphor technology, Color Precision binning, to it the C35 product family allowing customers to be in control of their CCT distribution. With the new technology, consistent colour can be produced within a single 7-step, 4step or 2-step MacAdam Ellipse centred in ANSI defined standard colour spaces.
“Working with IST for the LM-80 tests was a good choice. Being a certified test lab, IST showed its professionalism and provided all the necessary assistance for us to verify our performance. We look forward to further cooperation for new products in the pipeline,” comments Doan.
74
www.compoundsemiconductor.net October 2012
IST’s COO Jandel Lin mentions, the company’s LM- 80 lab started at the end of 2011 and had already been commissioned by over 20 manufacturers to conduct the test. Lin adds that SemiLEDs’ S35 is the first case to successfully pass the test at the IST lab and the results should significantly increase SemiLEDs’ marketing competitiveness in terms of quality.
IST’s CFO and spokesperson Selina Lin also adds that at the beginning of August, IST signed a MOU with Intertek HK as the reporting body.
Meaglow InGaN layer breaks barriers
The Canadian firm says its indium gallium nitride technology can lower the cost of producing green LEDs and laser diodes
Meaglow has developed a low temperature Migration Enhanced Afterglow film growth technique to produce a thick InGaN layer with strong yellow emission.
This recent result bodes well to increase the efficiency and lower production costs of green LEDs and laser diodes.
The company is currently seeking collaboration opportunities to enhance the material properties required by industry for lighting, display, medical, and military applications and other uses.
Meaglow’s Chief Scientist K. Scott Butcher, says, “It’s the brightest p-n junction I’ve ever seen in my life, and its right in the green gap.”
The green gap (540-610nm) is a major obstacle in the development of high-efficiency solid state lighting applications. It’s well known that LEDs produced in the green region, between red and blue, have rapidly declining efficiency.
Green and yellow in the middle of the colour spectrum, known as the “green gap”, is a section of the light spectrum where devices made from either nitride or phosphide are inefficient and difficult to fabricate.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131