Results 281 to 290 of about 8,746,494 (343)
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Enhancement of Light Output from a Supernova
Nature, 1963A possible mechanism to account for the intense light flashes observed in the supernova 3C 273 is presented. The mechanism is based on the theory that collective formation of a cluster of more massive stars with similar evolutionary time-scales may result in numerous Type II supernova explosions in a limited period of time.
S. A. COLGATE, A. G. W. CAMERON
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Increasing OLED output light efficiency via holography
SPIE Proceedings, 2004Following a brief review of OLED structures and emission models, we have proposed a phase holographic method to modify both sides of the substrate of an OLED to increase its output light emission efficiency. The holograms are designed with special masks simulating the emission layer of the OLED.
Han-Tsung Hsueh +3 more
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A Light Amplifier with High Light Output
1969Publisher Summary This chapter provides an overview of a light amplifier with high light output. Any large-scale projection of a picture signal requires the modulation of an intense light flux. Several methods involve a high-power standard light source that is modulated either by absorption as in the Sciatron or by diffraction as in the Eidophor.
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The Electrical Control of Lamp Light Output
Transactions of the Illuminating Engineering Society, 1967The basis of all electrical dimming systems is that the light output of an electric lamp varies with the current passing through it. Three methods may be recognised, namely, resistive, inductive and electronic; all are applicable, singly or in combination, to both incandescent and discharge lamps.
G. T. K. Lark, W. R. Stevens
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Large light output gas proportional scintillation counters
Nuclear Instruments and Methods, 1968Abstract The scintillating properties of the mixtures Ar-5% Xe and He-42.5% Xe are studied under the influence of a radial electric field. The secondary scintillation pulse, which is slow (∼ 10 μs), has an amplitude that exceeds by a factor of 200–300 the pulse amplitude from standard CsI(Tl) and NaI(Tl) scintillators.
A.J.P.L. Policarpo +2 more
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The light output of a mechanical lamp
Journal of Physics E: Scientific Instruments, 1975Light is emitted when relative motion of mercury and a glass occurs. In order to determine the factors affecting the light output and the feasibility of its use as a light source, an experimental device providing for the relative motion of contiguous surfaces of various metals and borosilicate glass was used.
A J Dixon, J R Hughes
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Sixty Thousand Hour Light Output Reliability of AlGaInP Light Emitting Diodes
IEEE Transactions on Device and Materials Reliability, 2006Both fixed current density and variable current density stress conditions are used to study light output degradation of (AlxGa1-x)0.5In0.5P light-emitting diodes (LEDs) as functions of LED stress current and LED stress time. Quantification of the resulting data indicates that (AlxGa1-x)0.5In0.5P LED degradation, D, is a linear function of current ...
Patrick N. Grillot +3 more
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Light output enhancement of light-emitting diodes with photonic crystal structure
SPIE Proceedings, 2010New light-emitting diodes (LED) structure constituted by the photonic crystal (PhC) is presented, and the effects of structure parameters are investigated. Relying on the results of investigation, the structure parameters of photonic crystal LED are optimized.
Xiaoling Wang, Chunhui Niu, Zhehai Zhou
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Two-dimensional photonic crystal couplers for unidirectional light output
Optics Letters, 2000We investigate the use of two-dimensional photonic crystal slabs to improve the directionality of output coupling from planar waveguides and distributed-feedback lasers. We present the theory underlying the operation of such structures and design criteria for emission in desired directions.
A, Mekis +3 more
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Micro‐pixel light emitting diodes with wavelength‐tunable output
physica status solidi c, 2008AbstractA novel design and implementation of a single‐chip wavelength tunable light emitting diode (LED) is introduced in this paper, with varying emission spectral characteristics ranging between 470 nm (blue) and 525 nm (green). The emission wavelength of green fluorescent microspheres (525 nm), acting as a colour conversion agent, is chosen to be ...
Choi, HW, Leung, CH, Lai, PT, Ng, WN
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