Home VLC using pinpin a-SiC:H multilayer devices

2014 ◽  
Vol 1693 ◽  
Author(s):  
P. Louro ◽  
V. Silva ◽  
I. Rodrigues ◽  
M. A. Vieira ◽  
M. Vieira
Keyword(s):  
Free Space ◽  
Optical Filter ◽  
Bright Light ◽  
Visible Spectrum ◽  
Visible Light Communication ◽  
Optical Signal ◽  
The Other ◽  
Electrical Model ◽  
Light Emitting ◽  
Wavelength Sensitivity

ABSTRACTIn this paper an integrated wavelength optical filter and photodetector for Visible Light Communication (VLC) is used. The proposed application uses indoor warm light lamps lighting accomplished by ultra-bright light-emitting diodes (LEDs) pulsed at frequencies higher than the ones perceived by the human eye. The system was analyzed at two different wavelengths in the visible spectrum, one in the blue (430 nm) and the other in the red (626 nm) regions, driven at different currents in order to change their optical intensities. The signals were transmitted into free space and measured using a pin-pin photodetector based on a-SiC:H/a-Si:H. This detector behaves as an optical filter with controlled wavelength sensitivity through the use of adequate optical biasing light. The output photocurrent was measured for different optical intensities of the transmitted optical signal and the extent of each signal was tested. An electrical model was used to support the physical operation of the device.

Transmission of Signals Using White LEDs for VLC Application

MRS Advances ◽  
2016 ◽  
Vol 1 (55) ◽  
pp. 3661-3666 ◽  
Author(s):  
P. Louro ◽  
V. Silva ◽  
J. Costa ◽  
M. A. Vieira ◽  
M. Vieira
Keyword(s):  
Optical Filter ◽  
Visible Light Communication ◽  
Indoor Navigation ◽  
Optical Signals ◽  
White Leds ◽  
Indoor Location ◽  
Optical Channels ◽  
Wavelength Sensitivity ◽  
Location Algorithm ◽  
The Individual

ABSTRCTIn this paper a photodetector working as an active optical filter device is used to detect modulated visible optical signals for applications based on Visible Light Communication (VLC). The proposed application demonstrates the viability of indoor positioning using VLC technology established by the modulation of indoor ultra-bright RGB white LEDs. The signals of the internal red and blue chips of the white LEDs were modulated at specific frequencies and the generated photocurrent was measured by a pin-pin photodetector based on a-SiC:H/a-Si:H. This device operates as a visible optical filter with controlled wavelength sensitivity through the use of adequate optical biasing light. Thus it is able to detect different wavelengths which allow the detection of the individual components of the tri-chromatic white LED. This possibility is the basis for the indoor location algorithm. We demonstrate the possibility of decoding four transmission optical channels supplied by two different wavelengths of white LEDs modulated under different bit sequences. The identification of the signals received by the photodetector allows the location identification of the photodetector position and supplies indoor navigation.

scholarly journals Implementasi Visible Light Communication (VLC) Pada Sistem Komunikasi

2017 ◽  
Vol 1 (1) ◽  
pp. 13
Author(s):  
ARSYAD RAMADHAN DARLIS ◽  
LITA LIDYAWATI ◽  
DECY NATALIANA
Keyword(s):  
Solar Cell ◽  
Visible Light ◽  
Communication System ◽  
Communication Systems ◽  
Light Emitting Diode ◽  
Bright Light ◽  
Visible Light Communication ◽  
Light Emitting ◽  
Transmission Distance ◽  
The Many

ABSTRAKPerkembangan teknologi telah menunjukkan peningkatan yang cukup signifikan, terutama untuk bidang komunikasi. Hal ini terbukti dengan banyaknya media komunikasi baik itu nirkabel dan kabel. Pada penelitian ini dimanfaatkan cahaya tampak sebagai media dalam sistem komunikasi, dimana selama ini cahaya hanya digunakan sebagai penerangan saja. Visible Light Communication (VLC) adalah sebuah teknologi komunikasi yang memanfaatkan pancaran cahaya tampak dari lampu pada sistem komunikasi. Sistem komunikasi visible light ini terdiri dari pemancar dan penerima. Pemancar terdiri dari Light Emitting Dioda, audio transformator dan baterai, dan pada penerima terdiri dari solar cell dan photodioda, amplifier dan catu daya. Hal-hal yang dapat mempengaruhi hasil output sistem komunikasi adalah jarak, terang cahaya lampu pemancar dan cahaya luar. Pada penelitian ini, komunikasi menggunakan VLC dapat dilakukan pada jarak pengiriman data sebesar 2,5 m dan dengan range frekuensi 600 Hz sampai dengan 45 kHz dimana data dapat disalurkan dengan baik.Kata kunci: Visible light, Sistem komunikasi, Light Emitting Dioda, solar cell, photodioda.ABSTRACTTechnological developments have shown a significant increase, especially in the field of communication. This is proved by the many communications media using both wireless and wired. This study utilized the visible light as a medium of communication system, which has been used as an illumination light only. Visible Light Communication (VLC) is a communication technology which utilize visible light emitted from the lamp in the communication system. The visible light communication system consists of a transmitter and receiver. The transmitter consists of a Light Emitting Diode, audio transformer and battery, and the receiver consists of a solar cell and a photodiode, amplifier and power supply. Things that can affect the output of the communication system is the distance, bright light and outdoor light. In the research, the results that obtained from this study is the data transmission distance of 2.5 m and a frequency range of 600 Hz to 45 kHz data can be routed properly.Keywords:  Visible light, Communication systems, Light Emitting Dioda, solar cell, photodioda.

scholarly journals Integrated Micro Circuitry Deceleration System Enhanced with Visible Light Communication

2019 ◽  
Vol 8 (2) ◽  
pp. 136-140
Keyword(s):  
Visible Light ◽  
New Technology ◽  
Visible Spectrum ◽  
Visible Light Communication ◽  
Optical Signal ◽  
Light Signal ◽  
Disc Brake ◽  
Warning Systems ◽  
Braking System ◽  
The One

Visible Light Communication (VLC) is the one of the advanced visible spectrum technology where we can communicate in the better way with a transmitter, a channel and a receiver. A new technology for next generation is evolved. Vehicles are connected anywhere and anytime by optical signal and light signal in VLC. Here the major instructions like braking system are communicated; therefore the risk and danger can be reduced. Thus an Integrated micro circuitry deceleration system is always required for the safety of innumerable valued lives. Collision avoidance and warning systems is equipped in vehicles for predicting the physical collision with an external body, such as another vehicle or a pedestrian to make the system smarter. In this system we have designed the microcontroller based automatic disc brake system, which will apply the instant brake to avoid the collision.

Optical Processing Devices for Optical Communications: Multilayered a-SiC:H Architectures

2009 ◽  
Vol 1153 ◽  
Author(s):  
Paula Louro ◽  
Manuela Vieira ◽  
M. A. Vieira ◽  
Miguel Fernandes ◽  
Alessandro Fantoni ◽  
...  
Keyword(s):  
Optical Switch ◽  
Visible Spectrum ◽  
Optical Signal ◽  
Electrical Model ◽  
Optical Processing ◽  
Device Architecture ◽  
Spectral Selectivity ◽  
Device Operation ◽  
Transmission Speed ◽  
Insight Into

AbstractIn this paper three multilayered architectures based on a-SiC:H with voltage controlled spectral selectivity in the visible spectrum range are analyzed. Multiple simultaneous modulated communication channels (red, green and blue or their polychromatic mixtures) were transmitted together at different frequencies. The combined optical signal was analyzed by reading out the photocurrent signal generated by the devices, under different applied voltages. Results show that the multiplexed signal depends on the device architecture and is balanced by the wavelength and transmission speed of each input channel, keeping the memory of the incoming optical carriers. In the single graded p-i’i-n configuration the device acts mainly as an optical switch while in two stacked p-i’-n-(ITO)-p-i-n configurations, the input channels are selectively tuned by shifting between forward and reverse bias. An electrical model, supported by a numerical simulation gives insight into the device operation.

Sulfonamides Are an Overlooked Class of Electron Donors in Luminogenic Luciferins and Fluorescent Dyes

2018 ◽  
Author(s):  
Deepak K. Sharma ◽  
Spencer T. Adams ◽  
Kate L. Liebmann ◽  
Adam Choi ◽  
Stephen Miller
Keyword(s):  
Fluorescent Dyes ◽  
Bright Light ◽  
Firefly Luciferase ◽  
Electron Donors ◽  
Light Emitting

Many fluorophores, and all bright light-emitting substrates for firefly luciferase, contain hydroxyl or amine electron donors. Here we show that sulfonamides can serve as replacements for these canonical groups. Unlike “caged” carboxamides, sulfonamide analogues enable bioluminescence, and sulfonamidyl luciferins, coumarins, rhodols, and rhodamines are fluorescent in water. Sulfonamide donors thus have previously unappreciated potential to expand the functional repertoire of luminescent molecules.

Growth and Characterization of AllnGaN/InGaN Heterostructures

1996 ◽  
Vol 423 ◽  
Author(s):  
J. C. Roberts ◽  
F. G. Mcintosh ◽  
M. Aumer ◽  
V. Joshkin ◽  
K. S. Boutros ◽  
...  
Keyword(s):  
High Performance ◽  
Visible Spectrum ◽  
Growth Conditions ◽  
Light Emitting ◽  
Mocvd Growth ◽  
Near Ultraviolet ◽  
Active Layers ◽  
Double Heterostructures ◽  
Lattice Matched

AbstractThe emission wavelength of the InxGa1−xN ternary system can span from the near ultraviolet through red regions of the visible spectrum. High quality double heterostructures with these InxGa1−xN active layers are essential in the development of efficient optoelectronic devices such as high performance light emitting diodes and laser diodes. We will report on the MOCVD growth and characterization of thick and thin InGaN films. Thick InxGa1−xN films with values of x up to 0.40 have been deposited and their photoluminescence (PL) spectra measured. AlGaN/InGaN/AlGaN double heterostructures (DHs) have been grown that exhibit PL emission in the violet, blue, green and yellow spectral regions, depending on the growth conditions of the thin InGaN active layer. Preliminary results of an AllnGaN/InGaN/AllnGaN DH, with the potential of realizing a near-lattice matched structure, will also be presented.

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