A 30,000-cd/m2, 50-lm/W,and 92%-luminance-uniformity flat discharge fluorescent lamp for LCD backlights

Abstract— A 5.2-in.-diagonal simple-structured argon-mercury cold-cathode flat discharge fluorescent lamp has been developed for LCD backlighting. A pair of insulated electrodes is provided at the top and bottom ends of the inner surface of the front glass plate. Phosphor is deposited on both the front and rear glass plates. A luminance of 30,000 cd/m² and a luminous efficacy of 50 lm/W were obtained with a luminance uniformity of 92% without the use of a diffuser sheet. A mechanism for obtaining the high luminous efficacy is described. Luminance can be dimmed down to 4% of the peak value by extending the pulse interval and/or by reducing the pulse amplitude.     

Wordline voltage generating system for low-power low-voltage flashmemories

A low-power wordline voltage generating system is developed for low-voltage flash memories. The limit for the stand-by current including the operation current for the band-gap reference and the stand-by wordline voltage generator is discussed. The system was implemented on a 1.8-V 32-Mb flash memory fabricated with a 0.25-μm flash memory process and achieved with very low stand-by current of 2 μA typically, and high operating frequency of 25 MHz in read operation at 1.8 V. A low-voltage level shifter with high-speed switching is also proposed     

A 100,000‐cd/m2 capacity‐coupled electrodeless discharge backlight with high efficacy for LC TVs

A capacity‐coupled electrodeless Hg discharge lamp has been developed for LC TV backlightings. By applying sinusoidal voltages which are 180° out of phase with a pair of external electrodes, a luminous uniformity of over 84% is attained in two types of lamps whose lengths are 190 and 390 mm. Luminance, efficacy, and input power to the lamp are 114,000 cd/m², 35 lm/W, and 21.5 W when the 390‐mm lamp is driven at 5 MHz. With a frequency below 1.1 MHz, eight 390‐mm lamps, connected in parallel to one another without external ballast impedance, can be driven by using a single inverter.     

Novel π-conjugated organoboron polymers: Poly (ethynylene-phenylene-ethynylene-borane)s

Summary Novel poly(ethynylene-phenylene-ethynylene-borane)s were prepared by polycondensation between bifunctional lithium acetylide and aryldimethoxyborane. The polymers obtained are expected as a novel type of organoboron π-conjugated polymers via vacant p-orbital of boron atom. The polymerization between dilithium 2,5-didodecyloxybenzene- 1,4-diethynilide and tripyldimethoxyborane [tripyl=2,4,6-triisopropylphenyl] gave the corresponding polymer in 67% yield. From gel permeation chromatographic analysis (THF, PSt standards), the number-average molecular weight of the polymer was found to be 2700. In the UV-vis spectrum of the polymer (in chloroform at room temperature), an absorption maximum was observed at 397 nm. The fluorescence emission spectrum (in chloroform, room temperature, excitation wavelength at 400 nm) showed its λ_max at 456 nm in the visible blue region. The polymers obtained were very soluble in common organic solvents such as THF, chloroform and benzene. Received: 11 April 2000/Accepted: 22 April 2000     

Frenkel pair accumulation induced crystallization of amorphous MgAl2O4

The epitaxial and homogeneous irradiation induced re-crystallization of amorphous MgAl₂O₄ was studied by means of continuous Frenkel pair accumulation in the molecular dynamics framework. Present results point out that the re-crystallization induced by Frenkel pair accumulation appears in both cases to be thermally enhanced but non diffusive. It is governed by a local rearrangement of each point defect in the homogeneous case, while spontaneous Frenkel pair recombination process in the crystalline part or at the interface drives the re-crystallization in the epitaxial case.     

Effects of secondary electron emission coefficients on Townsend's second ionization coefficient in argon dielectric barrier discharges

One‐dimensional fluid model simulations are performed to investigate how the secondary electron emission arising from ions (γ_i), metastable atoms (γ_m), and photons (γ_p) affect Townsend's second ionization coefficient (γ′) in argon dielectric barrier discharges. Since Townsend's breakdown criterion determines the value of γ′, it is naturally affected by the discharge condition such as the reduced electric field (E/p) as well as the combination of γ_i, γ_m, and γ_p. It also depends on the other contributions from the indirect ionization processes such as cumulative ionizations or metastable–metastable collision ionizations. When the nonionic electron‐yielding processes such as the effects of γ_m, γ_p, and the indirect ionizations are considered, the calculated γ′ increases largely under the higher pd (pressure times distance) branch of the Paschen curve. Since the experimental characteristics of γ′, which decreases with E/p, can hardly be explained without such nonionic processes, the contributions of those processes can be quite important in Townsend discharges especially under high pd conditions. These processes tend not to appear and γ′ tends to converge to γ_i under the lower pd branch of the Paschen curve. The value of γ_i can possibly be estimated by using γ′ under the lower pd condition. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Development of a novel aptamer-based sensing system using atomic force microscopy

Atomic force microscopy (AFM) can dynamically detect the adhesion or affinity force between a sample surface and a cantilever. This feature is useful as a detection method using aptamers--single-strand DNA that recognizes its target with very high affinity. The present study proposes a novel DNA aptamer-based sensing system using AFM. In this study, thrombin was chosen as the target molecule, and a DNA aptamer-based AFM sensing system based on competition was developed. The affinity force between the gold chip and the cantilever decreased as the concentration of thrombin increased. Moreover, a low detection limit of 0.2 nM was achieved. Therefore, the AFM sensing system used would be appropriate for the measurement of various chemical compounds.     

EXTRACTION AND SPECTROSCOPIC STUDIES OF HYDROGEN BONDING COMPLEXES OF tris(ACETYLACETONATO)ALUMINUM(III) WITH 3,5-DICHLOROPHENOL FOR A NOVEL SYNERGISM

ABSTRACT

Synergistic enhancement of the extraction of aluminium(III) with acetylacetone (Hacac) in heptane and carbon tetrachloride was observed by the addition of 3,5-dichlorophenol (DCP).This phenomenon is due to the formation of association complexes of Al(acac)₃ with DCP. From the extraction-equilibrium analysis, the association complexes were found to be Al(acac)₃·n(DCP) (n=1-3) and the overall association constants (β_ass,n) were determined. The hydrogen bonding of the hydroxyl hydrogen of DCP with Al(acac)₃ was evidenced by IR and 1H NMR spectroscopy. The β_ass,n values determined by IR were in good agreement with those’ obtained by the distribution method. The relationship between the hydrogen bond ability of tris(acetylacetonato)-metals(III) and their structure was discussed by comparison of β_ass,n for Al(acac)₃ with those for some metal(III)-acac chelates studied so far.     

Pb-free surface-finishing on electronic components’ terminals for Pb-free soldering assembly

Pb-free solderable surface finishing is essential to implement Pb-free solder assembly in order to meet with the growing demand of environmental consciousness to eliminate Pb from electronic products. Two types of widely applicable Pb-free surface finishing technologies are developed. One is the multilayer-system including Pd with Ni undercoat. Heat-resistance of Pd enables whole-surface-plating on to leadframe before IC-assembling process. The other is the double-layer-system with low-melting-point-materials, for example, thicker Sn underlayer and thinner Sn-Bi alloy overlayer, dilutes Sn-Bi alloy’s defects of harmful reactivity along with substrate metal and mechanical brittleness with keeping its advantages of solder-wettability and no whisker.