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991.
992.
Hyuk-Jin Kang Hyung-Jung KimJi-Seok Kim Woon-Yong ChoiWon-Shik Chu Sung-Hoon Ahn 《Robotics and Computer》2010
A light guide panel (LGP) is an element of the liquid crystal display (LCD) back light unit (BLU), which is used for display devices. In this study, the laser marking process is applied to the fabrication of light guide panels as the new fabrication process. In order to obtain a light guide panel which has high luminance and uniformity, four principal parameters such as power, scanning speed, ratio of line gap, and number of line were selected. A web-based design tool was developed to generate patterns of light guide panel via the network, and the tool may assist the designer to develop various prototype patterns. Topcon-BM7 was used for luminance measurement of each specimen with 100 mm×100 mm area. By Taguchi method, optimized levels of each parameter were found, and luminance of 3523 cd/cm2 and uniformity of 92% were achieved using the laser machined BLU. 相似文献
993.
994.
设计了一种高精度、外围元件较少的热电致冷温度控制电路。介绍了激光器温度控制电路的系统组成及工作原理,重点论述了采用基于TPS63000的热电致冷控制电路,通过MCU的数字PID控制算法对EML激光器温度进行精确调节的过程。实验结果表明,该电路完全符合EML激光器对温度稳定性的要求。 相似文献
995.
Ya‐Hui Yang Sidney S. Yang Kan‐Sen Chou 《Journal of the Society for Information Display》2010,18(10):745-748
Abstract— This study investigates the effects of subjecting zinc oxide (ZnO) thin films to laser irradiation. The optical, structural, and electrical properties of the as‐deposited and laser‐irradiated films at different laser energies were studied. The transmittances without/with laser irradiation showed a net increase from 85 to 92% (@550 nm) for 250‐nm ZnO films, indicating an improvement in sample crystal linity. In addition, laser treatment decreased the ZnO band gap. Composition structure analysis shows that the crystallinity increased when the laser energy increased. Thin‐film transistors (TFTs) with a ZnO active layer were fabricated. The mobility of as‐deposited ZnO TFT devices (0.19 cm2/V‐sec) increased more than 2.5 times for ZnO of unirradiated laser treatment (0.49 cm2/V‐sec). 相似文献
996.
HaengSeok Yang SangKyeong Yun JongHyeong Song SeungDo An HeungWoo Park Shyshkin Ihar Victor Yurlov Lapchuk Anatoly 《Journal of the Society for Information Display》2010,18(6):445-453
Abstract— The development of a compact, efficient VGA projection module to be embedded in mobile devices is reported. The design incorporates laser/laser diode (LD) light sources, Schlieren optics, and a one‐dimensional diffractive spatial optical modulator (SOM). During development, the optical parameters were determined and the relationships between the parameters to optimize the optical specifications were derived. The resulting optimized specifications enable us to manufacture two types of optical modu les as compact as 13 cc and with as little as 10% speckle contrast ratio. 相似文献
997.
Andrei Shchegrov John Khaydarov Stepan Essaian Greg Nemet Suren Soghomonyan Hakob Danielyan Armen Poghosyan Gevorg Gabrielyan 《Journal of the Society for Information Display》2010,18(8):589-595
Abstract— A novel green laser source, based on a monolithic cavity microchip laser platform, has been developed. The laser is designed to be a part of a miniature and efficient RGB light source for microdisplay‐based mobile projector devices. The use of highly efficient, periodically poled MgO‐doped lithium niobate as the non‐linear frequency doubler allows for a significant increase in the overall efficiency of the green microchip laser. Specifically, a 50–150‐mW green output with a wall‐plug efficiency exceeding 10% in the temperature range of greater than 40°C has been demonstrated. A compact package for this laser source with a volume less than 0.33 cm3 is discussed and results of performance tests are presented. 相似文献
998.
999.
Meng DengAuthor Vitae Xi YangAuthor VitaeMusa SilkeAuthor Vitae Weiming QiuAuthor VitaeMingsheng XuAuthor Vitae Gustaaf BorghsAuthor Vitae Hongzheng ChenAuthor Vitae 《Sensors and actuators. B, Chemical》2011,158(1):176-184
By exploiting the electrostatic interaction between positively charged pyrrole cation radicals and negatively charged graphene oxide (GO) sheets, we prepared polypyrrole/graphene oxide (PPy/GO) composite films by a one-step electrochemical process. We studied the effects of the polymerization current density and the GO content in electrolyte on the formation of PPy/GO coatings onto platinum neural microelectrode sites. As compared with pure PPy film, PPy/GO coatings show a rougher surface feature with micrometer-scale bulges. The impedance of the PPy/GO coated Pt electrode is only about 10% of the bare Pt electrode at the biological relevant 1 kHz, while the charge capacity density is more than two orders of the magnitude of the bare Pt electrode. Moreover, the PPy/GO coated Pt electrodes show higher performance than the PPy coated electrodes for the application of neural probe. 相似文献
1000.
Chander ShekharAuthor VitaeK.I. GnanasekarAuthor Vitae E. PrabhuAuthor VitaeV. JayaramanAuthor Vitae T. GnanasekaranAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):19-27
Indium oxide (In2O3) doped with 0.5-5 at.% of Ba was examined for their response towards trace levels of NOx in the ambient. Crystallographic phase studies, electrical conductivity and sensor studies for NOx with cross interference for hydrogen, petroleum gas (PG) and ammonia were carried out. Bulk compositions with x ≤ 1 at.% of Ba exhibited high response towards NOx with extremely low cross interference for hydrogen, PG and ammonia, offering high selectivity. Thin films of 0.5 at.% Ba doped In2O3 were deposited using pulsed laser deposition technique using an excimer laser (KrF) operating at a wavelength of (λ) 248 nm with a fluence of ∼3 J/cm2 and pulsed at 10 Hz. Thin film sensors exhibited better response towards 3 ppm NOx quite reliably and reproducibly and offer the potential to develop NOx sensors (Threshold limit value of NO2 and NO is 3 and 25 ppm, respectively). 相似文献