A crucial measurement for light emitting materials is their quantum yield.
A light emitting diode, or LED, first hit the lighting scene back in the 1920s.
According to Huygens's principle (see Diffraction) each aether particle, set vibrating by an incident wave, can itself act as a new centre of excitement, emitting a spherical wave; and similarly each particle on this wave itself produces wave systems. All systems which are emitted from a single source can by a suitable optical device be directed that they simultaneously influence one and the same aether particle.
Attenuation of gamma and x-ray emitting radionuclides, like the plastic sacks, is minimal.
Common Balm (Melissa) - M. officinalis is a well-known old garden plant, 2 to 3 feet high, emitting a grateful odour when bruised.
Emitting no sound or sensation, laser combs apply light energy to the scalp in a gentle and nourishing method that many people find therapeutic and relaxing.
Firefly is a term popularly used for certain tropical American click-beetles (Pyrophorus), due to their power of emitting light.
For electron microscopy, a conical tip with a flat emitting surface at the apex has proven to be the optimum design.
Has both a summit and a lateral crater, which are apparently connected and perpetually emitting steam.
He entered her room, emitting enough of his power to hide him from her senses.
He was a walking bubble and emitting piercing shrieks.
If a very long base is taken, it becomes increasingly open to doubt whether the portions of space emitting auroral light to the observers at the two ends are the same.
In some areas, permafrost is now emitting carbon, which could potentially accelerate the greenhouse effect and global warming.
In strictness this idea is appropriate only when the source is a luminous line, emitting cylindrical waves, such as might be obtained from a luminous point with the aid of a cylindrical lens.
In the Maribios district occur several volcanic lakelets, such as that of Masaya, besides numerous infernillos, low craters or peaks still emitting sulphurous vapour and smoke, and at night often lighting up the whole land with bluish flames.
It all gazes out on to a permanent lagoon inhabited by hippos that loll submerged, emitting plumes of water and deep guttural snorts.
It is as far as possible from being true that a body emitting homogeneous light would disappear on merely covering half the aperture of vision with a half-wave plate.
Juniperus Sabina is the savin, abundant on the mountains of central Europe, an irregularly spreading muchbranched shrub with scale-like glandular leaves, and emitting a disagreeable odour when bruised.
Lodge was, however, fully aware that it was necessary for syntonic telegraphy to provide a radiator capable of emitting sustained trains of waves.
New street lamps emitting white light are now being introduced in a few areas.
Nuclear Label - A single cell nucleus emitting light from red and green fluorescent probes used to detect cellular abnormalities.
Radioactivity The property of radionuclides of spontaneously emitting ionizing radiation.
Second, it is a potent radioactive carcinogen, emitting a relatively heavy alpha particle composed of 2 protons and 2 neutrons.
She is now actively involved in using IBS to fabricate silicon based light emitting devices and to fabricate novel superconductors.
That stands for Active Matrix Organic Light Emitting Diode and it makes for remarkably vibrant colors.
That's the way, Count, said Berg, lighting his pipe and emitting rings of smoke.
The annoying drone emitting from that overhead light is a sure sign that the fixture needs to be replaced.
The answer is to use a glowing halo instead of the emitting halo.
The light emitting diodes of the control panel display the force limits.
The light source was a halogen lamp used in the dental clinic, emitting mainly in the blue part of the spectrum.
The name has no reference to the appearance of the body to the eye; when emitting energy, its radiations will he of all wave-lengths, and if intense enough will appeal to the eye as luminous between about wave-lengths 7600 and 4000 tenth-metres; this intensity is a question of temperature, and as it is exquisitely inappropriate to speak of the bulk of the solar radiations as black, the writer will speak instead of amorphous radiations from an ideal radiator.
The point where the brakes start emitting this noise is just above the limit when your brake calipers will start damaging the rotor of your wheel.
The possibility of using ultra-intense lasers to produce commercial amounts of short-lived positron emitting sources for positron emission tomography (PET) is discussed.
The present project has sought to examine polarization properties of both edge-emitting and vertical cavity surface emitting lasers.
The vacuum may also start emitting dust out of its exhaust or dust may fall out of the back side of the unit when it is turned off.
They ignite with great ease, emitting a smoke freely, owing to the large proportion of carbon they contain.
They remove heavy pollutants and positively-charged particles out of the air by emitting negatively charged ions which bond to the pollutants, causing them to fall to the floor.
This isn't helped by the bike emitting an annoying beep every time you press a button.
Two of the five compartments into which it is divided by walls of deeply striated volcanic ash are constantly emitting steam, while a new vent displaying great activity has been opened at the base of the cone on the south side.
Very old dimmers have been known to not have such EMC filters making them prime candidates for emitting radio frequency interference too.
Warmer global temperatures are causing the arctic tundra to begin emitting carbon dioxide.
Wehnelt discovered that the same effect could be produced by using instead of a carbon filament a platinum wire covered with the oxides of calcium or barium, which when incandescent have the property of copiously emitting negative ions.
With the gas in excess a heavy lurid flame emitting dense volumes of smoke results, whilst if it be driven out in a sufficiently thin sheet, it burns with a flame of intense brilliancy and almost perfect whiteness, by the light of which colours can be judged as well as they can by daylight.
Your monitor, for example, creates color by emitting light through red, green, and blue phosphors.