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An LED’s power conversion (wall-plug) efficiency varies inversely with its optical output power. Wall-plug efficiency can exceed 100%, the unity efficiency, at low applied voltages and high temperatures.
Light emitting diodes bring relief to young cancer patients; NASA technology used for plant growth now in clinical trials - Marshall Center Space News Release 03-199 (11-13-03)For release: 11-05-03 Release: 03-199 Light emitting diodes bring relief to young cancer patients; NASA technology used for plant growth now in clinical trials A device using specialized light emitting diodes, based on NASA technology for plant growth in space, is continuing to show promise as a treatment to aid healing of bone marrow transplant patients. Use of the LED apparatus has advanced to the second phase of clinical trials in U.S. and foreign hospitals. Results from the first round of tests were highly encouraging, prompting researchers to expand the trials as they seek approval for the treatment as a standard of care for oral mucositis. Photo: Light emitting diodes can ease pain and promote wound healing in bone marrow transplant patients.
PAGE 1 of 6 - LED voltage control with limiting resistor Quick info about LEDs This is not an LED theory page, therefore i will not go into details about the LEDs. You can read the LED Theory for more extensive info. There are some things though that you need to have in mind: LEDs are current-depended components.
I find it easiest to do everything assembly-line fashion. Lay out your LEDs, push button, resistors, and wiring harness for the battery. Tin all legs of the components and the ends of the harness as well as the legs of the button. The wires on the harness are pre-tinned, but you want to be sure that the solder you're using sticks well to the components, so I always resolder them. Clip the leads on the resistors so they have one long lead and one lead about 1/4" long.
MP3302 MP3302 is a boost converter IC specifically designed for LED drive applications.
Nice Light Emitting Diode Projects This CircuitBook section is no longer updated, but still holds the maximum resources.
I went to Costco the other day with my wife to pick up some Christmas lights. While there, I found the most awesome christmas lights ever: the GE Color Effects G-35 . This string contains fifty "bulbs".
Arduino LED Exploration My program shows you all of the data on your Led from the first light to the normal operation light.
High-power LED's: the future of lighting! but... how do you use them? where do you get them?
While preparing for the Year 2000 power grid collapse, which somehow never materialized, I began experimenting with battery-powered room illuminators using super-bright LEDs. I learned a couple of interesting lessons the hard way.
Ok, so this is an easy step. First, with a Sharpie marker, draw a dot where you want to put your Push button and your LED. On my Altoids Flashlight, I put my light on the front, and the PB (Pushbutton) switch on the top.
Circuit parts (refer to the schematic diagram) R1: approximately 100k-ohm resistor (such as: Yageo CFR-25JB series) R3: current set resistor - see below Q1: small NPN transistor (such as: Fairchild 2N5088BU) Q2: large N-channel FET (such as: Fairchild FQP50N06L) LED: power LED (such as: Luxeon 1-watt white star LXHL-MWEC) Other parts:
This is a simple step by step guide to make your own Zippo Lighter LED Flashlight. A few years ago Zippo had a flashlight version of their amazing classic lighter. These Zippo flashlights never really caught on, most likely because they were dim and the batteries didn't last.
High efficiency white LEDs have advanced to the point where they can replace glow bulbs and other light sources not only as indicators, but also for illumination.