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31.
本文根据线光源高压汞灯的特点设计了一个用于光动力疗法的光反应室 ,它输出的光功率连续可调 ,波段选择简单灵活 相似文献
32.
Yellow electroluminescent diodes utilizing poly(2,5-bis(cholestanoxy)-1,4-phenylene vinylene) 总被引:2,自引:0,他引:2
C. Zhang S. Höger K. Pakbaz F. Wudl A. J. Heeger 《Journal of Electronic Materials》1993,22(4):413-417
We report visible yellow light emission from diodes made from a new derivative of poly(p-phenylene vinylene). The soluble
di-cholestanol derivative, poly(2,5-bis(cholestanoxy)-l, 4-phenylene vinylene), allows fabrication of the light emitting diodes
by spinning the electroluminescent polymer film from solution prepared at room temperature with no subsequent processing or
heat treatment required. These initial devices turn on at >8 V and have a peak emission wavelength of 570 nm at room temperature
with quantum efficiencies of approximately 0.3% photons per electron. 相似文献
33.
Although photocells are commonly characterized under AM1.5G 100 mW cm−2 (1 sun) illumination, their performance under low light illumination is also important, because photocells are frequently used for indoor applications. In this study, polymer photocells based on a bulk heterojunction composite consisting of a low energy gap polymer PTB7 and unmodified C70 prepared with a halogen-free solvent 1,2,4-trimethylbenzene have been characterized under the illumination of 1 sun or below. A typical photocell with the power conversion efficiency (PCE) of 4% at 1 sun shows the PCE of approximately 7% at 10−3 sun, which seems to fit for some indoor applications such as a permanent power source for a wireless sensor node. The sublinear dependence of short-circuit photocurrent on light intensity as well as the increase of fill-factor under low light illumination yields the increased efficiency under low light illumination. An analysis employing a one-diode equivalent circuit model suggests that the increased parallel resistance as well as the decreased saturation current of the diode under low light illumination accounts for the latter feature. It is also pointed out that the parallel resistance and/or the saturation current under dark strongly influence the PCE of a photocell under low light illumination. In addition, the dependence of the device performance on the light intensity is found to be useful for analyzing the effects of the thermal treatment and the PFN interlayer at cathode. 相似文献
34.
机载可见光摄像机调光方法研究 总被引:1,自引:1,他引:1
针对机载光电平台可见光摄像机在执行任务时所面临的场景多样性的特点,对现有调光方法进行了研究,提出一种灰度平均值与区域信息熵相结合的调光方法.方法分为3个步骤,首先是灰度平均值法初调,获得大致清晰的图像;其次是地面人员提取感兴趣目标区域;最后是目标区域内利用信息熵法进行调光.实验结果表明,利用此方法可以获得亮度合适、目标... 相似文献
35.
36.
液晶电视中的背光源常常采用LED直射式入射,但是如果采用具有光选择作用(light-extracting)的导光板,则可以使用更少的LED灯以获得更薄的背光源。 相似文献
37.
《Organic Electronics》2014,15(8):1822-1827
A patterning scheme for poly(3,4-ethylenedioxythio-phene):poly(styrenesulfonate) (PEDOT:PSS) is reported. With a silver interlayer, the conductive PEDOT:PSS film can be patterned down to micrometer scales by traditional photolithography, and this patterning scheme can be applied on large-area flexible substrates. Through systematical investigations, the patterning processes have no obvious influence on both the bulk and surface properties of PEDOT:PSS films. Efficient organic light emitting diodes (OLEDs) are realized based on this patterned PEDOT:PSS anode, and they show comparable performance to those devices with an indium tin oxide (ITO) anode. High-resolution OLED pixel arrays are also demonstrated. Our interlayer approach here has an advantage of patterning PEDOT:PSS with high resolution and large scale, and it is also compatible with traditional photolithographic processes which substantially save the capital cost. Results indicate that the photographically patterned conductive PEDOT:PSS film becomes a promising candidate for eletrical eletrode material in organic electronic applications. 相似文献
38.
White‐Light‐Emitting Diodes: Targeting Cooling for Quantum Dots in White QDs‐LEDs by Hexagonal Boron Nitride Platelets with Electrostatic Bonding (Adv. Funct. Mater. 30/2018)
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39.
本文从CIE色度原理解释了LED显示系统的像素结构,利用LED显示系统混色理论,设计出基于四原色RGBW像素结构的LED显示系统电路,并论证了该电路在高效节能、减少光污染等方面的优势。 相似文献
40.
Benzofuranyl benzene incorporating naphthyl (phenothiazinyl or dimesitylboryl) entities via meta-conjugation have been synthesized. These compounds exhibit bipolar transport characteristic with mobilities in the range of 10−5 to 10−4 cm2/V s at an electric field of 4 × 105 V/cm. The compounds with two naphthyl or dimesitylboryl substituents emit in the violet region with good solution quantum yields. The OLEDs fabricated from the benzofuranyl/dimethylboryl, benzofuranyl/naphthyl and benzofuranyl/dimethylboryl/phenathiazine derivatives have maximum external efficiencies of 1.01%, 1.41% and 3.14%, respectively. 相似文献