scholarly journals Design of an LED Spot Light System with a Projection Distance of 10 km

Crystals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 524 ◽  
Author(s):  
Chi-Shou Wu ◽  
Kuan-Yu Chen ◽  
Xuan-Hao Lee ◽  
Shih-Kang Lin ◽  
Ching-Cherng Sun ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Optical Design ◽  
White Led ◽  
Light Emitting ◽  
First Order ◽  
Light System ◽  
Power Injection ◽  
Projection Distance ◽  
Injection Power ◽  
New Location

We designed a spot light system with an illumination range of 10 km. In the designed system, an appropriate white light-emitting diode (LED) was selected according to the exitance and injection power required. Subsequently, through a first-order optical design, the geometry of the lens and reflector was determined using geometrical calculation. Because the central illuminance of the projection spot of the reflector was 2.5 times that of the cover lens, we first considered the fabrication error of the reflector. According to the adjustment of the optimized distance between the white LED and reflector, we modified the design of the cover lens to fit the new location of the white LED. An LED spot light module containing 16 spot light units was used. The module’s power injection was only 68.2 W. Because of the excellent performance of the designed system in terms of the divergence angle of the projection beam and maximum luminous intensity, which were 1.6° and 2,840,000 cd, respectively, the projection distance of the LED spot light module was 3.37 Km, according to the ANSI regulation. Finally, a spot light system with nine modules and capable of achieving a projection distance of 10 km was successfully fabricated.

Optical design of a light-emitting diode lamp for a maritime lighthouse

2015 ◽  
Vol 54 (11) ◽  
pp. 3252 ◽  
Author(s):  
D. Jafrancesco ◽  
L. Mercatelli ◽  
P. Sansoni ◽  
D. Fontani ◽  
E. Sani ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Optical Design ◽  
Light Emitting

A high quality liquid-type quantum dot white light-emitting diode

Nanoscale ◽  
2016 ◽  
Vol 8 (2) ◽  
pp. 1117-1122 ◽  
Author(s):  
Chin-Wei Sher ◽  
Chin-Hao Lin ◽  
Huang-Yu Lin ◽  
Chien-Chung Lin ◽  
Che-Hsuan Huang ◽  
...  
Keyword(s):  
Quantum Dot ◽  
White Light ◽  
Light Emitting Diode ◽  
White Led ◽  
High Quality ◽  
Light Emitting ◽  
Uv Led ◽  
Liquid Type ◽  
Color Conversion

In this study, a liquid-type QD white LED is demonstrated as an efficient color-conversion layer in UV LED packages.

Behavioral response of adult caddisflies (Trichoptera) to blue and green light-emitting diode lamps

Zoosymposia ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 59-62
Author(s):  
GORO KIMURA ◽  
GORO TAJIKA ◽  
TOSHIHIRO KUSAMA ◽  
TSUTOMU TANIKAWA
Keyword(s):  
Uv Light ◽  
Diversity Index ◽  
Light Emitting Diode ◽  
Broad Band ◽  
Green Light ◽  
Visible Spectrum ◽  
Ultraviolet Spectrum ◽  
White Led ◽  
Light Emitting ◽  
Wiener Diversity Index

To clarify the effect of the visible spectrum, we collected Trichoptera adults using blue, green, and white light-emitting diode (LED) lamps and black light (BL) lamps. Except for white LED lamps, all lamps emitted broad-band wavelengths in the ultraviolet spectrum. A total of 212 adult Trichoptera were trapped. The most individuals were attracted by BL (96), followed blue (74), green (32), and white (10). Hydroptilidae spp. was the most abundant taxa among the lamps (183 individuals, 86.3%), followed by Cheumatopsyche brevilineata (23 individuals, 10.8%). Only Hydroptilidae spp. was common to all lamps. The Shannon–Wiener diversity index (H’) was highest at 0.96 for BL, followed by green (0.53), and blue (0.28). Trichoptera were attracted to both UV light and visible light. These results suggest that BL is the most useful for faunistic investigations of Trichoptera.

Dependence of Yellow Phosphor on Optical and Electrical Properties of the White Light Emitting Diode Chip

2006 ◽  
Vol 510-511 ◽  
pp. 106-109 ◽  
Author(s):  
Chang Sik Son ◽  
Ho Jung Chang ◽  
Kang Hyun Jaekal ◽  
Young Chol Chang ◽  
Soo Wohn Lee
Keyword(s):  
Electrical Properties ◽  
Bias Voltage ◽  
White Light ◽  
Light Emitting Diode ◽  
White Led ◽  
Optical And Electrical Properties ◽  
Maximum Luminance ◽  
Mixing Conditions ◽  
Light Emitting ◽  
Yellow Phosphor

We prepared the surface mounted white light emitting diode (LED) chips by using yellow phosphors on the blue LED chip. The optical and electrical properties of prepared white LED chips were investigated. The yellow phosphor mixed with transparent epoxy was coated on the prepared LED chip. The optimum mixing conditions with epoxy and yellow phosphor is obtained at the mixing ration of epoxy: yellow phosphor = 97 : 3 wt %. The maximum luminance and light emitting efficiency are above 80,000 cd/m2 and 23.2 lm/W, respectively, at the bias voltage of 2.9 V. There was no distinct change in the luminance strength with changing of the yellow phosphor ratios. The flowing current of the white LED chip is about 30 mA at 2.9 V.

Optical design of adjustable light emitting diode for different lighting requirements

2012 ◽  
Vol 21 (12) ◽  
pp. 127105 ◽  
Author(s):  
Jia-Ning Lu ◽  
Jie Yu ◽  
Yu-Zhen Tong ◽  
Guo-Yi Zhang
Keyword(s):  
Light Emitting Diode ◽  
Optical Design ◽  
Light Emitting

Effects of Different Package Structures on Thermal Properties of High Power White LED

2012 ◽  
Vol 503 ◽  
pp. 397-401 ◽  
Author(s):  
Zhe Ran Sun ◽  
Da Ming Wu ◽  
Ya Jun Zhang ◽  
Jian Zhuang ◽  
Kai Fang Dang
Keyword(s):  
Thermal Properties ◽  
Thermal Resistance ◽  
White Light ◽  
High Power ◽  
Light Emitting Diode ◽  
White Led ◽  
Forward Voltage ◽  
Light Emitting

The characteristics of several package structures of high power white Light emitting diode (LED) are described in this paper. The influence of different structures on thermal properties is analyzed. Forward voltage method is used to test the thermal resistance of LED chips.

Optical design of dental light using a remote phosphor light-emitting diode package for improving illumination uniformity

2018 ◽  
Vol 57 (21) ◽  
pp. 5998 ◽  
Author(s):  
Sie-Wook Jeon ◽  
Sunghyun Kim ◽  
Jina Choi ◽  
Inseok Jang ◽  
Younghyun Song ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Optical Design ◽  
Light Emitting ◽  
Remote Phosphor

scholarly journals Photocatalytic Degradation of 2-Chlorophenol Using Ag-Doped TiO2Nanofibers and a Near-UV Light-Emitting Diode System

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Ju-Young Park ◽  
In-Hwa Lee
Keyword(s):  
Phase Transformation ◽  
Photocatalytic Degradation ◽  
Uv Light ◽  
Light Emitting Diode ◽  
Sol Gel ◽  
Order Equation ◽  
Light Emitting ◽  
First Order ◽  
Uv Led ◽  
Diode System

This report investigated the photocatalytic degradation of 2-chlorophenol using TiO2nanofibers and Ag-doped TiO2nanofibers, synthesized using the sol-gel and electrospinning techniques, and an ultraviolet light-emitting diode (UV-LED) system as a UV light source. The crystallite size of the Ag-doped TiO2nanofibers was smaller than that of the TiO2nanofibers, because silver retrained phase transformation not only controls the phase transformation but also inhibits the growth of anatase crystallites. The activation energies for the grain growth of the TiO2nanofibers and the Ag-doped TiO2nanofibers were estimated to be 20.84 and 27.01 kJ/mol, respectively. The photocatalytic degradation rate followed a pseudo-first-order equation. The rate constants (k) of the TiO2nanofibers and the Ag-doped TiO2nanofibers were 0.056 and 0.144 min−1, respectively.

scholarly journals Development and validation of a triple-LED surgical loupe device for fluorescence-guided resections with 5-ALA

2021 ◽  
pp. 1-9
Keyword(s):  
Predictive Value ◽  
Aminolevulinic Acid ◽  
Light Emitting Diode ◽  
Malignant Gliomas ◽  
Protoporphyrin Ix ◽  
Emission Spectra ◽  
White Led ◽  
Light Emitting ◽  
Blinded Study ◽  
Development And Validation

OBJECTIVE Fluorescence-guided resections performed using 5-aminolevulinic acid (5-ALA) have been studied extensively using the BLUE400 system. The authors introduce a triple–light-emitting diode (LED) headlight/loupe device for visualizing fluorescence, and compare this to the BLUE400 gold standard in order to assure similar and not more or less sensitive protoporphyrin-IX visualization. METHODS The authors defined the spectral requirements for a triple-LED headlight/loupe device for reproducing the xenon-based BLUE400 module. The system consisted of a white LED (normal surgery), a 409-nm LED for excitation, a 450-nm LED for background illumination, and appropriate observation filters. The prototype’s excitation and emission spectra, illumination and detection intensities, and spot homogeneity were determined. The authors further performed a prospectively randomized and blinded study for fluorescence assessments of fresh, marginal, fluorescing and nonfluorescing tumor samples comparing the LED/loupe device with BLUE400 in patients with malignant glioma treated with 20 mg/kg body weight 5-ALA. Tumor samples were immediately assessed in turn, both with a Kinevo and with a novel triple-LED/loupe device by different surgeons. RESULTS Seven triple-LED/loupe devices were analyzed. Illumination intensities in the 409- and 450-nm range were comparable to BLUE400, with high spot homogeneity. Fluorescence intensities measured distally to microscope oculars/loupes were 9.9-fold higher with the loupe device. For validation 26 patients with malignant gliomas with 240 biopsies were analyzed. With BLUE400 results as the reference, sensitivity for reproducing fluorescence findings was 100%, specificity was 95%, positive predictive value was 98%, negative predictive value was 100%, and accuracy was 95%. This study reached its primary aim, with agreement in 226 of 240 (94.2%, 95% CI 0.904–0.968). CONCLUSIONS The authors observed only minor differences regarding spectra and illumination intensities during evaluation. Fluorescence intensities available to surgeons were 9.9-fold higher with the loupe device. Importantly, the independent perception of fluorescence achieved using the new system and BLUE400 was statistically equivalent. The authors believe the triple-LED/loupe device to be a useful and safe option for surgeons who prefer loupes to the microscope for resections in appropriate patients.

Sign in / Sign up

Export Citation Format

Share Document