White light phosphors

Yang WJ, Chen TM (2005) Luminescence of Eu- and Mn-coactivated CaAl2Si20g as a potential white-light phosphor for UVLED. Chem Mater 17 3883... 

Huang CH, Liu WR, Chen TM (2010) Single-phased white-light phosphors Ca9Gd(P04)7 Eu, Mn under near-ultraviolet excitation. J Phys Chem C 114 18698... 

Setlur AA, Comanzo HA, Srivastava AM, Beers WW (2005) Evaluation of a White Light Phosphor for UV-LEDs-Ca2NaMg2V30i2 Eu. J Electrochem Soc 152 H205-H208... 

Thus, we have two units of measurement of intensity. One is related to scattering from a surface, L, i.e.- in foot-lamberts and the other is related to emittance, H, i.e.- in lumens per square foot. Although we have assumed "white" light up to now, either of these two can be wavelength dependent. If either is wavelength dependent, then we have a pigment (reflective- but more properly called scattering) with intensity in foot-lamberts, or an emitter such as a lamp or phosphor (emittance) with intensity in lumens. 

The light-emission characteristics of a white-light-emitting EL device with a doubly doped ZnS Pr,Ce,F phosphor layer have been described. It was observed that optimization of the co-doping of Ce enhances the emission characteristics compared to an EL device with a singly doped ZnS Pr,F layer.22 An electrical characterization of Ce-doped ZnS TbOF EL thin films has been reported Ce doping was seen to improve the radiative emission efficiency leading to improved performance of Ce co-doped film.23... 

This UV radiation is converted into visible radiation by means of the fluorescence of the phosphor powder coating. The phosphor material uses the UV radiation as an excitation source and produces fluorescent emission in the visible region, with a broad spectrum to give off the white light that we can see. A good variety of combinations of phosphors are used (Shionoya and Yen, 1999). The principal field of application of fluorescent lamps is general lighting, for which they constitute efficient devices. 

Dimedone (0.3%)/phosphoric acid (10% in ethanol) Dark-gray spots (white light) dark pink fluorescing spots (UV) after heating (110°C, 15 min) 1,111... 

Fluorescent lights (for room illumination but not usually for scientific instruments) A low-pressure gas (He, Ne, Ar, Na) is excited, but not ionized, in a sealed tube the fluorescence output is transformed into a crude approximation of visible sunlight by placing a phosphor (Zn) on the inner surface of the tube the phosphor emits a pseudo-"white" light. The efficiency of electrical energy transformed into photon energy is between 17% and 21%. 

Fluorescent lights are electrical discharge tubes partially filled by Ne (red emission), Ar (blue emission), or K, Hg (blue-green), or Na vapor, or other material, which fluoresce when electrical current is sent thought the tube the characteristic narrow-band fluorescent emission forces a coating of CaWC>3 or ZnO or other "phosphors" on the inside of the tube to fluoresce as "white light."... 

The red television phosphor is based on europium. This phosphor is also used in trichromatic fluorescent lamps where a blend of red, blue and green phosphors gives white light. 

Other groups reported the solution synthesis of a cerium-doped inorganic phosphor library (73) to optimize their structure as luminescence down-converters in white Light Emitting Diodes (LEDs) and the use of cathodoluminescence (CL) (74) to identify... 

The EML with a multilayer structure for the lanthanide ions is very different from that of other phosphor materials such as iridium complexes. Multilayer structures with EMLs usually emit hybrid light which is used in white light emitting OLEDs [33]. For lanthanide complexes extremely pure light is achievable, because their emission is due to electronic transitions of... 

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