-
Digital AVR frequency meter
Posted 15 April -
Automatically switches off DMM
Posted 12 October -
Create multicolored LEDs
Posted 12 October -
Voltage curves on PC
Posted 12 October -
Ultrasonic Parking Sonar Schematic
Posted 28 July -
Battery Solutions for Energy Harvesting
Posted 28 July -
Simple Gas Leak Detector Circuit
Posted 30 April -
FTDI Infrared
Posted 28 April -
3 Axis Accelerometer Using PIC16F887
Posted 25 April -
Simple 3V adjustable Car adapter
Posted 14 April
New LED efficacy 1A operation
Japanese LED pioneer Nichia has claimed it has achieved a record luminous-efficacy figure in a device running at 1A drive current. A figure of 135 lm/W was reported for four 1×1-mm die connected in series.
Yukio Narukawa and colleagues note that at 1913 lm their device had a higher flux than a 20W-class fluorescent lamp and 1.5 times the luminous efficacy of a tri-phosphor fluorescent lamp.
Nichia also improved its LED’s optical performance, focusing on making sure as little light as possible remains trapped inside it by total internal reflection through optimizing its extraction efficiency. To do this, Narukawa’s team switched the traditional translucent nickel-gold alloy electrode on top of the device that only allows 40% of light through to indium-tin-oxide (ITO) material that lets 90% of light past it. They also switched from a traditional flat sapphire substrate to one with a pattern, which is less prone to trapping light.
