Energy into Light

One application of modem solid-state electronic devices is semiconductor materials that convert electrical energy into light. These light-emitting diodes (LEDs) are used for visual displays and solid-state lasers. Many indicator lights are LEDs, and diode lasers read compact discs in a CD player. The field of diode lasers is expanding particularly rapidly, driven by such applications as fiber optic telephone transmission. 

Cx electronically excited product) depends on the efficiency es of the production of excited product molecules, and on the efficiency of the excited product molecules (or other molecules present in the reaction mixture) in transforming excitation energy into light. In most of the chemiluminescence reactions investigated so far this efficiency is identical with the fluorescence efficiency of the molecules concerned, so that... 

The primary scintillator converts excitation energy into light. Two commonly used primary scintillators are PPO (2,5-diphenyl-oxazole) and butyl-PBD (2-(4 -tert-butyl-phenyl)-5-(4 -biphenyl)-l,3,4-oxadiazole). The pulse voltage produced by butyl-PBD is about 20% greater than that produced by PPO, but its usefulness is reduced because of its limited solubility. Suitable concentrations of PPO and butyl-PBD are about 5 g/1 and 7 g/1 respectively. With alkaline samples butyl-PBD produces a brownish colour in the scintillation cocktail. In highly quenched samples, a higher concentration may be required for optimum efficiency. 

Power conversion is a conversion from one form of energy to another. It doesn t preclude the conversion of input energy into light, instead of more conventional load profiles that power supply engineers are generally accustomed to. In fact, I found out the hard way how difficult this area of power conversion can really be. Far more difficult than your average dc-dc converter ... 

Chemiluminescence is a prominent example of converting chemical energy into light and, thus, may be considered as a reversal of photochemistry. Such a symmetry is illustrated by Scheme 1, in which Rg denotes the... 

In 1879, Thomas Edison in the United States and Joseph Swan in England invented the incandescent lamp, thus making it possible to convert electric energy into light. The invention of the light bulb promoted the use of electricity in people s everyday life. Electricity entered human lives. Lead—acid battery demand increased. However, large-scale production of lead—acid batteries was constrained by the technology of their manufacture. 

A lamp is a device for converting electrical energy into light energy. 

Just as electrons can travel long distances through a wire, photons can travel under the whole Atlantic Ocean through a glass fiber. An important modem trend is to communicate via optical fibers, and therefore we need to be able to convert electrical energy into light, and back again. This chapter will cover some of those conversions. 

The involvement of LES in electrochemical processes may allow the conversion of electrical energy into light. This phenomenon, which is the reverse of the previously described photogalvanic effect, is called electrochemiluminescence (ECL). One of the most noticeable examples of ECL is that concerning Ru(bpy)3 in acetonitrile solution [57,58]. When cyclic square waves between the potentials of formation of Ru(bpy)3" and Ru(bpy)3 (figure 8) are applied at a Pt electrode immersed in the solution, a red luminescence is observed which continues indefinitely if the electrical potential is maintained. The reaction mechanism, illustrated in figure 22 involves reactions (56) - (59) ... 

Thus efficacy is measured in lumens per watt the greater the efficacy the better is the lamp s performance in converting electrical energy into light energy. 

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