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Full-Text Articles in Engineering
Electroluminescent Device Comprising A Transparent Structured Electrode Layer Made From A Conductive Polymer, Aemilianus G. J. Staring, David Braun
Electroluminescent Device Comprising A Transparent Structured Electrode Layer Made From A Conductive Polymer, Aemilianus G. J. Staring, David Braun
Electrical Engineering
A description is given of an electroluminescent (EL) device (1) composed of polymeric LEDs comprising an active layer (7) of a conjugated polymer and a transparent polymeric electrode layer (5) having electroconductive areas (51) as electrodes. Like the active layer (7), the electrode layer (5) can be manufactured in a simple manner by spin coating. The electrode layer (5) is structured into conductive electrodes (51) by exposure to UV light. The electrodes (9) and (51) jointly form a matrix of LEDs for a display. When a flexible substrate (3) is used, a very bendable EL device is obtained.
Temperature Dependence Of Electrical And Optical Modulation Responses Of Quantum-Well Lasers, T. Keating, Xiaomin Jin, Shun Lien Chuang, K. Hess
Temperature Dependence Of Electrical And Optical Modulation Responses Of Quantum-Well Lasers, T. Keating, Xiaomin Jin, Shun Lien Chuang, K. Hess
Electrical Engineering
We present theory and experiment for high-speed optical injection in the absorption region of a quantum-well laser and compare the results with those of electrical injection including the carrier transport effect. We show that the main difference between the two responses is the low-frequency roll-off. By using both injection methods, we obtain more accurate and consistent measurements of many important dynamic laser parameters, including the differential gain, carrier lifetime, K factor, and gain compression factor. Temperature-dependent data of the test laser are presented which show that the most dominant effect is the linear degradation of differential gain and injection efficiency …
Parallel Ac-Ac Converters Using Stationary Master Slave Control, Taufik, F. E. Villaseca
Parallel Ac-Ac Converters Using Stationary Master Slave Control, Taufik, F. E. Villaseca
Electrical Engineering
This study proposes parallel ac-ac converters using Stationary Master Slave Control with Sinusoidal Pulse Width Modulation to achieve voltage regulation and equal current sharing among parallel generators such that it minimizes the total production cost. Development of Pspice model representing the parallel ac-ac converters is presented and then simulated. In addition, computer simulations are also used to perform robustness study on the parallel converters.
Optical Gain Measurements Based On Fundamental Properties And Comparison With Many-Body Theory, T. Keating, S. H. Park, J. Minch, Xiaomin Jin, Shun-Lien Chuang, T. Tanbun-Ek
Optical Gain Measurements Based On Fundamental Properties And Comparison With Many-Body Theory, T. Keating, S. H. Park, J. Minch, Xiaomin Jin, Shun-Lien Chuang, T. Tanbun-Ek
Electrical Engineering
We present high accuracy measurements of gain, loss, and transparency energy in long-wavelength semiconductors based on a hybrid approach using the fundamental relationship between the gain and the spontaneous emission spectra. Independent measurements of optical gain, transparency energy, and loss show the accuracy and validity of this technique. These results are compared with those obtained by the non-Markovian gain model with many-body effects under the spontaneous emission transformation method. It is found that the hybrid approach for the gain spectrum alleviates many of the problems related to the poor signal to noise ratio in the amplified-spontaneous emission near and below …
Evaluation Of Caltrans District 10 Automated Warning System, Year Two Progress Report, Art Maccarley
Evaluation Of Caltrans District 10 Automated Warning System, Year Two Progress Report, Art Maccarley
Electrical Engineering
District 10 of the California Department of Transportation (Caltrans) encompasses an area of seasonal fog and dust-related visibility problems that have been the cause of numerous multi-car traffic collisions, many fatal. In 1990, motivated by the expansion of State Route 120 (SR 120) connecting Interstate Highway 5 (I-5) and State Route 99 (SR 99), Caltrans proposed a sophisticated multi-sensor automated warning system as a means for reducing incidents in this high-traffic area. This proposal, and the significant development effort that followed, culminated in the implementation of Phase 1 of the Caltrans Automated Warning System, or “CAWS”, which entered service in …
An Efficient Finite Difference Time Domain (Fdtd) Technique For Modeling A Reflector Antenna System With Partial Circular Symmetry, Dean Arakaki, Wenhua Yu, Raj Mittra
An Efficient Finite Difference Time Domain (Fdtd) Technique For Modeling A Reflector Antenna System With Partial Circular Symmetry, Dean Arakaki, Wenhua Yu, Raj Mittra
Electrical Engineering
This paper presents an efficient method for solving a large body scattering problem, viz., a paraboloidal reflector antenna system with only partial circular symmetry. The asymmetry in the system is introduced by two factors, viz., the microstrip feed and an inhomogeneous radome. The paper presents a novel approach, based on the reciprocity principle and the “equivalent aperture” theory, to handle the asymmetry problem and still take advantage of the circular symmetry of the large paraboloid of revolution to render the problem manageable
Electroluminescent Illumination System, Dirk J. Broer, David Braun, Antonius H.J. Venhuizen, Christianne R.M. De Witz
Electroluminescent Illumination System, Dirk J. Broer, David Braun, Antonius H.J. Venhuizen, Christianne R.M. De Witz
Electrical Engineering
An illumination system has an active layer which includes an electroluminescent material, the active layer being located between an optically transparent electrode layer and a reflective electrode layer. A reflective polarizer is present at a side of the transparent electrode layer facing away from the active layer. A sub-beam incident on the polarizer and having an unwanted polarization is reflected back to the active layer, where it is again partially depolarized to recover a component having the desired state of polarization. The invention also relates to a flat-panel picture display device which includes such an illumination system.
Crosstalk And Image Uniformity In Passive Matrix Polymer Led Displays, David Braun, J. Rowe, G. Yu
Crosstalk And Image Uniformity In Passive Matrix Polymer Led Displays, David Braun, J. Rowe, G. Yu
Electrical Engineering
Passive matrix displays based on polymer and organic light-emitting diodes suffer from crosstalk, when the emission of light from one pixel depends on the operation of another pixel. We use circuit simulation in order to explain the causes of crosstalk and to quantify the consequences. This work analyzes how crosstalk arises from electrode resistance, pixel leakage current, and the location of faulty pixels. All factors influence both image uniformity and the power consumption of the display.
Simulations Of Passive Matrix Polymer Image Sensors, David Braun, G. Yu
Simulations Of Passive Matrix Polymer Image Sensors, David Braun, G. Yu
Electrical Engineering
Two-dimensional passive photodiode matrices are hardly useful for image sensing due to the crosstalk between pixels. This crosstalk makes it difficult to recover information from individual pixels. A switching unit attached to each sensing unit has been the common solution in image sensors (such as in CMOS sensors and in TFT-PiN a-Si photosensors). A novel organic photodiode with voltage-switchable photosensitivity was developed recently. Passive photodiode matrices made with such organic photodiodes can be used for image sensing applications. This circuit simulation study demonstrates an effective scheme to extract images from passive photodiode matrices, concluding that individual photodiode parameters determine the …
Fabrication Of Visible Light Emitting Diodes Soluble Semiconducting Polymers, Alan J. Heeger, David Braun
Fabrication Of Visible Light Emitting Diodes Soluble Semiconducting Polymers, Alan J. Heeger, David Braun
Electrical Engineering
Visible light LEDs are produced having a layer of conjugated polymer which is cast directly from solution or formed as a gel-processed admixture with a carrier polymer. The LEDs can be formed so as to emit polarized light.
Long-Term Memory Motion-Compensated Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod
Long-Term Memory Motion-Compensated Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod
Electrical Engineering
Long-term memory motion-compensated prediction extends the spatial displacement vector utilized in block-based hybrid video coding by a variable time delay permitting the use of more frames than the previously decoded one for motion compensated prediction. The long-term memory covers several seconds of decoded frames at the encoder and decoder. The use of multiple frames for motion compensation in most cases provides significantly improved prediction gain. The variable time delay has to be transmitted as side information requiring an additional bit rate which may be prohibitive when the size of the long-term memory becomes too large. Therefore, we control the bit …