排序方式: 共有13条查询结果,搜索用时 37 毫秒
1.
Deterministic diffractive diffusers for displays 总被引:1,自引:0,他引:1
Parikka M Kaikuranta T Laakkonen P Lautanen J Tervo J Honkanen M Kuittinen M Turunen J 《Applied optics》2001,40(14):2239-2246
A LCD backlighting device that uses a diffractive light extractor has been developed for applications in which pointlike light sources are employed. The novel system eliminates the images of light sources, which appear as bright lines emanating from each source in the conventional diffractive approach. In addition, the system illuminates the LCD uniformly: Modulation of the diffractive structure as a function of position is used to control the output field of this extended planar light source. 相似文献
2.
Kari mnkknen Tuula T. Pakkanen Joni Hietala Esko J. Pkknen Pertti Pkknen Timo Jskelinen Terho Kaikuranta 《Polymer Engineering and Science》2002,42(7):1600-1608
A comprehensive experimental study was carried out to replicate sub‐micron features using the injection molding technique. For the experiments, five different plastic materials were selected according to their flow properties. The materials were polycarbonate (PC), styrene‐butadiene block copolymer (SBS), impact modified poly(methyl methacrylate), methyl methacrylate‐acrylonitrile‐butadiene‐styrene polymer (MABS), and cyclic olefin copolymer (COC). Nanofeatures down to 200‐nm line width and with aspect ratios (aspect ratio = depth/width) of 1:1 could be replicated. In all selected materials, the greatest differences between the materials emerged when the aspect ratio increased to 2:1. The most favorable results were obtained with the use of high flow polycarbonate as the molding material. The best replication results were achieved when melt and mold temperatures were higher than normal values. 相似文献
3.
J Savolainen O Kortekangas-Savolainen M Nermes M Viander A Koivikko K Kalimo EO Terho 《Canadian Metallurgical Quarterly》1998,53(5):506-512
To assess the incidence of HIV infection and risk factors associated with HIV seroconversion among patients attending clinics for sexually transmitted diseases (STD), medical record reviews were conducted in 12 clinics in 7 U.S. cities. The records of all patients who initially tested negative for HIV from 1991 through 1996 and who received at least one additional HIV test during the study period were reviewed. In each of 7 cities, 5 to 112 patients seroconverted. Of the 286 seroconverters identified in total, 53% (152 of 286) were heterosexual men and 28% (81 of 286) were women. HIV incidence rates among men who have sex with men (MSM) ranged by city from 0.81 to 7.0 new infections/100 person-years. Rates among heterosexual men and women ranged from 0.018 to 1.2 infections/100 person-years. Multivariate analyses showed that drug use was associated with HIV seroconversion only among heterosexuals. Most new HIV infections in these clinics are being transmitted heterosexually and are associated with drug use. Nevertheless, MSM, particularly young MSM, are at greatest risk for HIV in this population: 1 of 47 seroconvert/year. The effective use of targeted prevention efforts depends upon the continued ability to monitor the incidence of HIV infection. 相似文献
4.
R2R gravure and inkjet printed RF resonant tag 总被引:1,自引:0,他引:1
Mark Allen Changwoo LeeByungjoon Ahn Terho KololuomaKeehyun Shin Sunglim Ko 《Microelectronic Engineering》2011,88(11):3293-3299
The fabrication of passive circuitry by gravure and inkjet printing is studied. A chipless inductively coupled RF resonant tag is analyzed as a test structure. A floating-bridge layout is employed to provide high yield when fabricated by roll-to-roll (R2R) printing. The conducting first layer and insulating second layer are R2R gravure printed with silver nanoparticle ink and a thermally cross-linkable dielectric ink, respectively. Above 10 MS/m conductivity is obtained for the first layer, which passes three times through the 5 m long drying unit at 5 m/min speed. The floating bridge is inkjet printed with silver nanoparticle ink and the prototype tag is measured over a reading distance of ca. 2 cm. An equivalent circuit model is presented and the model parameters are optimized to obtain a best fit to the measured frequency response. This indirect measurement provides an estimate of 4.3 μm for the thickness of the dielectric layer sandwiched between the conducting top and bottom layers. Application possibilities for the all-printed RF resonant tag are outlined. 相似文献
5.
6.
The fabrication process and the operation characteristics of a fully roll-to-roll printed resistive write-once-read-many memory on a flexible substrate are presented. The low-voltage (<10 V) write operation of the memories from a high resistivity '0' state to a low resistivity '1' state is based on the rapid electrical sintering of bits containing silver nanoparticles. The bit ink is formulated by mixing two commercially available silver nanoparticle inks in order to tune the initial square resistance of the bits and to create a self-organized network of percolating paths. The electrical performance of the memories, including read and write characteristics, is described and the long-term stability of the less stable '0' state is studied in different environmental conditions. The memories can find use in low-cost mass printing applications. 相似文献
7.
A joint between Sn95.5Ag4Cu0.5 (mass%) solder and an Ag/Pd thick film was soldered by dipping at 260°C for 3–30 sec. Shrinkage
voids and Sn grain growth were characterized as well as their transformation kinetics. Void shrinkage occurred in the zone
near the top surface of the joint. Shrinkage was always accompanied by colonies of ternary/quaternary meta-eutectic that were
the regions solidified last in the joint. The Sn grains accumulated into two bands across the joint during solidification:
one was transverse through the thickness and the other was parallel to the solder pad. 相似文献
8.
Tobias Lehnert Petra Herbeck‐Engel Jens Adam Gabi Klein Terho Kololuoma Michael Veith 《Advanced Engineering Materials》2010,12(5):379-384
Low temperature processable materials with high dielectric constants are required for application on flexible organic substrates, for example, in printed electronics. To date, mainly organic polymers with embedded functional particles have been investigated for this purpose. For the first time, we present a printable dielectric composite material composed of ferroelectric high permittivity particles (BaTiO3) bonded by a mainly inorganic sol–gel derived network. The exemplary optimization of the properties by varying the sol–gel precursor illustrates the potential of sol–gel chemistry for printable functional materials. An operational gravure printed capacitor including printed silver electrodes is presented. The measured dielectric constants are among the highest reported in literature for low temperature cured films with moderate dissipation factors. Besides these promising dielectric properties, this composite film shows a ferroelectric response. 相似文献
9.
Aoife M. Murphy Caren E. Smith Leanne M. Murphy Jack L. Follis Toshiko Tanaka Kris Richardson Raymond Noordam Rozenn N. Lemaitre Mika Khnen Jose Dupuis Trudy Voortman Eirini Marouli Dennis O. Mook‐Kanamori Olli T. Raitakari Jaeyoung Hong Abbas Dehghan George Dedoussis Rene de Mutsert Terho Lehtimki Ching‐Ti Liu Fernando Rivadeneira Panagiotis Deloukas Vera Mikkil James B. Meigs Andre Uitterlinden Mohammad A. Ikram Oscar H. Franco Maria Hughes Peadar O' Gaora Jos M. Ordovs Helen M. Roche 《Molecular nutrition & food research》2019,63(22)
10.
Terho Kololuoma Ari H. O. Krkkinen Ari Tolonen Juha T. Rantala 《Thin solid films》2003,440(1-2):184-189
The synthesis of directly UV-photopatternable pure and antimony-doped organo-tin materials is presented. UV-photopatternability has been achieved by using the synthesized benzoylacetone modified tin and antimony 2-isopropoxyethoxides. Photopatterned pure and antimony-doped organo-tin films are crystallized by thermal annealing in order to obtain conductive SnO2 and Sb:SnO2 thin films. The molar ratio between benzoylacetone and metal alkoxides has to be 2 in order to obtain crack-free, good-quality structures. The effects of UV-irradiation, increasing antimony doping level and benzoylacetone concentration on the electrical properties of the single-layered films are analyzed. The highest obtained conductivity was 20 S/cm. Benzoylacetone concentration and UV-irradiation has only a negligible effect on the film electrical conductivities. 相似文献