Institution
Philips
Company•Vantaa, Finland•
About: Philips is a company organization based out in Vantaa, Finland. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 68260 authors who have published 99663 publications receiving 1882329 citations. The organization is also known as: Koninklijke Philips Electronics N.V. & Royal Philips Electronics.
Papers published on a yearly basis
Papers
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TL;DR: It is found that tau(M) can be directly related to the so-called Gilbert damping factor sigma that describes damping of GHz precessional motion of the magnetization vector.
Abstract: We present a microscopic model that successfully explains the ultrafast equilibration of magnetic order in ferromagnetic metals at a time scale tau(M) of only a few hundred femtoseconds after pulsed laser excitation. It is found that tau(M) can be directly related to the so-called Gilbert damping factor sigma that describes damping of GHz precessional motion of the magnetization vector. Independent of the spin-scattering mechanism, an appealingly simple equation relating the two key parameters via the Curie temperature T(C) is derived, tau(M) approximately c(0)h/k(B)T(C)sigma, with h and k(B) the Planck and Boltzmann constants, respectively, and the prefactor c(0) approximately 1/4). We argue that phonon-mediated spin-flip scattering may contribute significantly to the sub-ps response.
378 citations
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06 Jan 1994TL;DR: In this paper, a broadband cholesteric polarizer is described, in which the pitch of the molecular helix in the layer is varied in such a manner that the difference between the maximum pitch and the minimum pitch is at least 100 nm.
Abstract: A broadband cholesteric polarizer is described, as well as a method of manufacturing such a polarizer. Said polarizer comprises an optically active layer of a polymer material having a cholesteric order, said material being oriented so that the axis of the molecular helix extends transversely to the layer. In accordance with the invention, the polarizer is characterized in that the pitch of the molecular helix in the layer is varied in such a manner that the difference between the maximum pitch and the minimum pitch is at least 100 nm. The optically active layers are preferably provided on substrates which bring about a conversion of circularly polarized light into linearly polarized light. Three different methods of manufacturing such broadband polarizers are described.
378 citations
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TL;DR: In this article, the absolute light outputs of BGO, CsI(Tl) and some new Ce-doped crystals have been measured to an accuracy of about /spl plusmn/5% using calibrated XP2020Q photomultipliers and standard S3590.03 and S2740.03 photodiodes.
Abstract: The absolute light outputs of BGO, CsI(Tl) and some new Ce-doped crystals have been measured to an accuracy of about /spl plusmn/5% using calibrated XP2020Q photomultipliers and standard S3590.03 and S2740.03 photodiodes. The use of small crystals, 9 mm in diameter and 1 mm thick, reduces the corrections for imperfections in the light collection process and in the photoelectron collection by the photomultipliers. The measured light-output of 8500/spl plusmn/350 ph/MeV (photons/MeV) for the BGO crystals agree well with the earlier measurement done by Holl et al. (1988). The carried out study highlighted the importances of the spread in the published emission spectra of the crystals which seems to limit measurement accuracy. Finally, a simple comparative method of measuring light output to an accuracy of /spl plusmn/10%, is proposed using an uncalibrated XP2020 photomultiplier and a 1 mm thick BGO crystal as a standard.
378 citations
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TL;DR: In this paper, the synthesis and photophysical properties of blue emitting iridium(III) complexes were reported, and the role played by electron withdrawing substituents of a different nature and also how the substitution position of the same group influenced the spectroscopical behaviour.
377 citations
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28 Feb 2005TL;DR: In this paper, an active matrix LED display has a light-dependent device for detecting the brightness of the display element and threshold voltage measurement circuitry for measuring a threshold voltage of a pixel the drive transistor.
Abstract: An active matrix LED display has a light-dependent device for detecting the brightness of the display element and threshold voltage measurement circuitry for measuring a threshold voltage of a pixel the drive transistor. Compensation for ageing of the display element is thus provided by an optical feedback path, and compensation for drive transistor threshold variations is provided by measurement of the threshold voltage. This provides a reliable compensation scheme for the threshold voltage variations, whilst also providing ageing compensation.
376 citations
Authors
Showing all 68268 results
Name | H-index | Papers | Citations |
---|---|---|---|
Mark Raymond Adams | 147 | 1187 | 135038 |
Dario R. Alessi | 136 | 354 | 74753 |
Mohammad Khaja Nazeeruddin | 129 | 646 | 85630 |
Sanjay Kumar | 120 | 2052 | 82620 |
Mark W. Dewhirst | 116 | 797 | 57525 |
Carl G. Figdor | 116 | 566 | 52145 |
Mathias Fink | 116 | 900 | 51759 |
David B. Solit | 114 | 469 | 52340 |
Giulio Tononi | 114 | 511 | 58519 |
Jie Wu | 112 | 1537 | 56708 |
Claire M. Fraser | 108 | 352 | 76292 |
Michael F. Berger | 107 | 540 | 52426 |
Nikolaus Schultz | 106 | 297 | 120240 |
Rolf Müller | 104 | 905 | 50027 |
Warren J. Manning | 102 | 606 | 38781 |