There are two quite different kinds: CFLs (compact fluorescent lamps) and LED (light-emitting-diode) lamps. What's the difference between them, how do they work, and which is best? Let's take a closer look!Photo: A typical dimmable LED lamp. Light comes from a ring of tiny LEDs ...
An invisible, infrared light beam, similar to the ones that Tom Cruise dodged, shoots into the chamber from a light-emitting diode (LED) (2). The same chamber contains a photocell (3), which is an electronic light detector that generates electricity when light falls on it. Normally, when...
Irradiations were conducted using four diode panels emitting light with the wavelength of 365 nm (UV) or 523 nm (G), depending on the test. The lamps were operating at full power, achieving 128 W per color as described by the producer. The samples were stored in a refrigerator at 8 °...
It shines a bright light down onto your desk from an LED (light-emitting diode) mounted on the bottom of the mouse. The light bounces straight back up off the desk into a photocell (photoelectric cell), also mounted under the mouse, a short distance from the LED. The photocell has a...
The light is produced by a light-emitting diode (LED); right next to it, there's a photoelectric cell—a component that detects the reflected LED light and turns it back into an electrical signal. As you move your mouse around, the pattern of red light reflected off the desk changes ...