Impact of visible light and humidity on the stability of high-power light emitting diode packaging material

2021 ◽  
Vol 130 (8) ◽  
pp. 083101
Author(s):  
Abdul Shabir ◽  
Cher Ming Tan
Keyword(s):  
Visible Light ◽  
High Power ◽  
Light Emitting Diode ◽  
Packaging Material ◽  
Light Emitting ◽  
The Stability

The Design of High Power LED Headlamp

2013 ◽  
Vol 423-426 ◽  
pp. 2098-2103
Author(s):  
Wen Lin Chen ◽  
Zhen An ◽  
Chao Qun Xiang ◽  
Chen Yang Liu ◽  
Li Na Hao
Keyword(s):  
High Power ◽  
Heat Dissipation ◽  
Light Emitting Diode ◽  
Current Drive ◽  
Constant Current ◽  
Light Emitting ◽  
High Power Led ◽  
Drive Circuit ◽  
Led Headlamp ◽  
The Stability

With the continuous development of LED(Light-Emitting Diode) manufacturing technology, the high power white LED is gradually applied in the field of all kinds of lighting .But with working time increasing of LED chips, their junctions temperature continue increasing, which lead to decrease light-emitting efficiency and reliability of LED chip, and even be failure. According to the serious heating of LED chip, this paper has been designed a fin-type aluminum radiator panels using Pro/E software. A LED constant current drive circuit is designed by using LTC3783 chip. With the ANSYS software, thermal analysis was carried out on the fin-type aluminum radiator panels, and eventually the mode of high power LED headlamps is determined. The stability of the LED constant current drive circuit is verified through experiments. The LED headlamps of 90W worked for ten hours, and the results of the experiments showed that the LED chip junctions temperature measured are less than 75°Cso we can solve heat dissipation of high power LED headlamps effectively.

Phosphor concentration and geometry for high power white light emitting diode

2010 ◽  
Author(s):  
Kyung-Mi Moon ◽  
Se-Hwan An ◽  
Hyung-Kun Kim ◽  
Jung-Hye Chae ◽  
Yong-Jo Park
Keyword(s):  
White Light ◽  
High Power ◽  
Light Emitting Diode ◽  
Light Emitting

High-Power CW Operation of GaInAsP/InP Superluminescent Light-Emitting Diode with Tapered Active Region

2001 ◽  
Vol 40 (Part 2, No. 7A) ◽  
pp. L678-L680 ◽  
Author(s):  
Takeshi Yamatoya ◽  
Shigeaki Sekiguchi ◽  
Fumio Koyama ◽  
Kenichi Iga
Keyword(s):  
Active Region ◽  
High Power ◽  
Light Emitting Diode ◽  
Light Emitting ◽  
Cw Operation

Reliability of High-Power Light Emitting Diode Attached With Different Thermal Interface Materials

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Xin Li ◽  
Xu Chen ◽  
Guo-Quan Lu
Keyword(s):  
High Power ◽  
Heat Dissipation ◽  
Light Emitting Diode ◽  
Temperature Cycling ◽  
Fluorescent Light ◽  
Light Sources ◽  
Light Emitting ◽  
Die Attach ◽  
Nanosilver Paste ◽  
Interconnection Material

As a solid electroluminescent source, white light emitting diode (LED) has entered a practical stage and become an alternative to replace incandescent and fluorescent light sources. However, due to the increasing integration and miniaturization of LED chips, heat flux inside the chip is also increasing, which puts the packaging into the position to meet higher requirements of heat dissipation. In this study, a new interconnection material—nanosilver paste is used for the LED chip packaging to pursue a better optical performance, since high thermal conductivity of this material can help improve the efficiency of heat dissipation for the LED chip. The bonding ability of this new die-attach material is evaluated by their bonding strength. Moreover, high-power LED modules connected with nanosilver paste, Sn3Ag0.5Cu solder, and silver epoxy are aged under hygrothermal aging and temperature cycling tests. The performances of these LED modules are tested at different aging time. The results show that LED modules sintered with nanosilver paste have the best performance and stability.

The Intellectual Lighting And Data Transmission System based On RGBW Light Emitting Diodes

2021 ◽  
pp. 63-68
Author(s):  
Daniil S. Shiryaev ◽  
Olga A. Kozyreva ◽  
Ivan S. Polukhin ◽  
Sergey A. Shcheglov ◽  
Svetlana A. Degtiareva ◽  
...  
Keyword(s):  
Visible Light ◽  
Data Transmission ◽  
Light Transmission ◽  
Transmission Rate ◽  
Light Emitting Diode ◽  
Spectral Characteristics ◽  
System Component ◽  
Transmission Channel ◽  
Error Vector Magnitude ◽  
Light Emitting

The system of intellectual lighting data transmission via visible light is developed and manufactured. Spectral characteristics of a downlink which uses the red crystal of a RGBW light emitting diode for data transfer were studied. The DALI protocol-based radiation chromaticity control system which allows us to set different lighting scenarios with constant data transmission rate was developed. The radiation chromaticity range covers almost the entire colour gamut in the colour space. The system of high-frequency matching of system component impedances was developed and frequency characteristics of the suggested scheme were studied for development of the system. Optimal parameters of the signal for visual light communication such as carrier frequency, modulation type and band were determined. Observation of the constellation diagram which represents different values of the complex amplitude of the keyed signal in the form of a complex number on a quadrature plane (cosine and sine components of the carrying signal) and of fixation of the amplitude of the error vector magnitude (EVM) was selected as a method of study of the transmission channel quality. The value of EVM in the visible light transmission channel was significantly lower for signals with amplitude modulation than for phase-manipulated signals. When implementing different lighting change scenarios, radiation of other crystals of the light emitting diode crystals not used for transmission did not lead to increase of EVM by more than one percent.

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