White Light Realization and Color Coordinate Calculation of OLED Devices

There are several kinds of methods in improving the efficiency of organic light emitting diodes (OLEDs). In this work, we used a co-deposited hole blocking layer to improve the efficiency of OLEDs. The structure of the component is: ITO/ MTDATA(15 nm) /NPB(40 nm) /BCP(10 nm) /BCP: Alq(15 nm) /LiF(0.7 nm)/ Al(180 nm). We changed the mixing rate of the BCP:Alq layer to be capable of hole blocking and electron transporting, and then improved the efficiency of OLEDs. Finally, we prepared white light OLED with doping Rubrene in NPB. When the concentration of the NPB: Rubrene layer was 2.0 wt.%, the device could emit the white light at 100 mA/cm2, and the luminance was above 2300 cd/m2, and the color coordinate was x = 0.36, y = 0.37.

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The Measurement of LED Domain Wavelength Based on LabVIEW

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.228-229.759 ◽

2011 ◽

Vol 228-229 ◽

pp. 759-763

Author(s):

Wei Guo Lin ◽

Yu Fu Wang ◽

Ming Zhong Yang

Keyword(s):

Measurement Error ◽

Data Acquisition ◽

White Light ◽

Measurement Method ◽

Data Acquisition System ◽

Present Measurement ◽

Color Quality ◽

Linear Ccd ◽

Color Coordinate ◽

Data Acquisition Card

The domain wavelength is the most important colorimetric parameter of tested LED, it decides the LED color quality. The data acquisition system is build of linear CCD, monochromator，and PCI data acquisition card, which can obtain the chart of distribution value of 1urninous intensity and color coordinate of LED with LabVIEW. This paper present measurement method based on the table method, the measurement method is looking-up two domain wavelengths which distance is 1nm through slope which get from testing LED color coordinate and white light LED coordinate, and calculate the domain wavelength of testing LEDs using LabVIEW and mathematic interpolation, the measurement error of domain wavelength is 1 nm.

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WHITE UPCONVERSION LUMINESCENCE FROM (Yb3+/Tm3+/Ho3+) TRIDOPED GdF3 NANORODS AFTER HEAT TREATMENT

Functional Materials Letters ◽

10.1142/s1793604712500245 ◽

2012 ◽

Vol 05 (03) ◽

pp. 1250024 ◽

Cited By ~ 7

Author(s):

LINNA GUO ◽

YUHUA WANG ◽

JIA ZHANG ◽

YANZHAO WANG ◽

PENGYU DONG

Keyword(s):

Heat Treatment ◽

White Light ◽

Dopant Concentration ◽

Upconversion Luminescence ◽

Excitation Power ◽

Chromaticity Diagram ◽

Transmission Electron ◽

Emission Color ◽

Color Coordinate ◽

Ft Ir

A series of Ho3+/Yb3+/Tm3+ tridoped GdF 3 nanorods with different dopant concentrations were synthesized by a hydrothermal method. Transmission electron microscope (TEM) images indicate that the length and diameter of the nanorods is about 90 nm and 31 nm, respectively on average. No bright white upconversion light was observed from the samples with different Yb 3+, Ho 3+ or Tm 3+ concentrations. Unexpectedly, the emission color coordinates of the samples after heat treatment move toward the central white region of the chromaticity diagram, and among these samples, the color coordinate (0.349, 0.329) of GdF 3:15% Yb 3+, 0.1% Ho 3+, 0.8% Tm 3+ is the most close to the standard white light (0.333, 0.333). This is unlike previous reports in which white light was achieved via tuning dopant concentration or excitation power. The reasons for the above phenomenon are presented by means of FT-IR spectra and the energy level diagram of dopants.

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Color Offset in the Process of High-Power LED Life Aging

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.498 ◽

2016 ◽

Vol 693 ◽

pp. 498-503 ◽

Cited By ~ 1

Author(s):

L.Y. Zhang ◽

Y.P. Cui ◽

Z.N. Luo ◽

L. Zhou

Keyword(s):

Blue Light ◽

White Light ◽

High Power ◽

Light Emitting Diodes ◽

Light Emitting Diode ◽

Color Temperature ◽

Constant Current ◽

Light Emitting ◽

Color Coordinate ◽

High Power Led

In order to study color offset of the high-power white light and blue light LED in the whole life, a series of high-power white light and blue light emitting diodes are lighted continuously under a constant current. In the light of different period of time, measured the light emitting diode emission spectrum, color coordinate, color temperature of the light emitting diodes are measured at different periods; light luminous flux, color coordinate and color temperature changes are also measured under different currents. The experimental results show that the color of LED is different at different period under the same current, and is also different under a variable current. The article studied the influence of different factors on the color offset, and pointed out that the high-power LED color offset is caused by not only phosphors aging but also more major changes of the material itself. Furthermore, the results will provide a reference to the application of white LED and for the further study.

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FeXIV Line Emission Polarization of the July 11, 1991 Solar Corona

International Astronomical Union Colloquium ◽

10.1017/s0252921100026002 ◽

1994 ◽

Vol 144 ◽

pp. 541-547

Author(s):

J. Sýkora ◽

J. Rybák ◽

P. Ambrož

Keyword(s):

High Resolution ◽

Solar Corona ◽

Emission Line ◽

Solar Eclipse ◽

White Light ◽

Preliminary Analysis ◽

Line Emission ◽

Total Solar Eclipse ◽

Degree Of Polarization ◽

High Resolution Images

AbstractHigh resolution images, obtained during July 11, 1991 total solar eclipse, allowed us to estimate the degree of solar corona polarization in the light of FeXIV 530.3 nm emission line and in the white light, as well. Very preliminary analysis reveals remarkable differences in the degree of polarization for both sets of data, particularly as for level of polarization and its distribution around the Sun’s limb.

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White-Light Coronal Structures: Streamers and CMEs

International Astronomical Union Colloquium ◽

10.1017/s0252921100025045 ◽

1994 ◽

Vol 144 ◽

pp. 82

Author(s):

E. Hildner

Keyword(s):

Emission Line ◽

Electron Density ◽

White Light ◽

Coronal Mass Ejections ◽

X Rays ◽

Solar Cycles ◽

Temperature Function ◽

X Ray ◽

Eclipse Observations ◽

Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

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Periodic Variations in the Coronal Green Line Intensity and their Connection with the White-light Coronal Structures

International Astronomical Union Colloquium ◽

10.1017/s0252921100064484 ◽

2000 ◽

Vol 179 ◽

pp. 197-200

Author(s):

Milan Minarovjech ◽

Milan Rybanský ◽

Vojtech Rušin

Keyword(s):

Time Resolution ◽

White Light ◽

Short Time Scale ◽

High Time Resolution ◽

Green Line ◽

Periodic Intensity ◽

Coronal Green Line ◽

Significant Intensity ◽

Short Time ◽

Coronal Structures

AbstractWe present an analysis of short time-scale intensity variations in the coronal green line as obtained with high time resolution observations. The observed data can be divided into two groups. The first one shows periodic intensity variations with a period of 5 min. the second one does not show any significant intensity variations. We studied the relation between regions of coronal intensity oscillations and the shape of white-light coronal structures. We found that the coronal green-line oscillations occur mainly in regions where open white-light coronal structures are located.

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Factors Influencing Electrophysiologic Responsivity in Normal Adults

Journal of Speech and Hearing Research ◽

10.1044/jshr.0804.323 ◽

1965 ◽

Vol 8 (4) ◽

pp. 323-347

Author(s):

Robert Goldstein ◽

Benjamin RosenblÜt

Keyword(s):

Conditioned Stimulus ◽

White Light ◽

Pure Tone ◽

Alpha Rhythm ◽

White Women ◽

White Men ◽

Inverse Relation ◽

Factors Influencing ◽

Electrodermal Responses ◽

Normal Adults

Electrodermal and electroencephalic responsivity to sound and to light was studied in 96 normal-hearing adults in three separate sessions. The subjects were subdivided into equal groups of white men, white women, colored men, and colored women. A 1 000 cps pure tone was the conditioned stimulus in two sessions and white light was used in a third session. Heat was the unconditioned stimulus in all sessions. Previously, an inverse relation had been found in white men between the prominence of alpha rhythm in the EEG and the ease with which electrodermal responses could be elicited. This relation did not hold true for white women. The main purpose of the present study was to answer the following questions: (1) are the previous findings on white subjects applicable to colored subjects? (2) are subjects who are most (or least) responsive electrophysiologically on one day equally responsive (or unresponsive) on another day? and (3) are subjects who are most (or least) responsive to sound equally responsive (or unresponsive) to light? In general, each question was answered affirmatively. Other factors influencing responsivity were also studied.

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TOWARD GENERATION OF HIGH POWER ULTRAFAST WHITE LIGHT LASER USING FEMTOSECOND TERAWATT LASER IN A GAS-FILLED HOLLOW-CORE FIBER

Proceedings of the 70th International Symposium on Molecular Spectroscopy ◽

10.15278/isms.2015.fb10 ◽

2015 ◽

Author(s):

Walid Tawfik

Keyword(s):

White Light ◽

High Power ◽

Hollow Core ◽

Core Fiber ◽

Terawatt Laser

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The Efficacy of Virtual Chromoendoscopy in the Diagnosis of Portal Hypertensive Gastropathy

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.253.chr ◽

2016 ◽

Vol 25 (3) ◽

pp. 289-293

Author(s):

Anda Carmen Achim ◽

Stefan Cristian Vesa ◽

Eugen Dumitru

Keyword(s):

Diagnostic Criteria ◽

White Light ◽

Narrow Band Imaging ◽

Endoscopic Examination ◽

Kappa Statistics ◽

Portal Hypertensive Gastropathy ◽

Mosaic Pattern ◽

White Light Endoscopy ◽

A New Technique ◽

Virtual Chromoendoscopy

Background: Diagnosis of portal hypertensive gastropathy (PHG) is based on endoscopic criteria. I-scan technology, a new technique of virtual chromoendoscopy, increases the diagnostic accuracy for lesions in the gastrointestinal tract. Aim: To establish the role of i-scan endoscopy in the diagnosis of PHG. Method: In this prospective study, endoscopic examination was conducted first by using white light and after that i-scan 1 and i-scan 2 technology in a group of 50 consecutive cirrhotic patients. The endoscopic diagnostic criteria for PHG followed the Baveno criteria. The interobserver agreement between white light endoscopy and i-scan endoscopy was determined using Cohen’s kappa statistics. Results: Forty-five of the 50 patients met the diagnostic criteria for PHG when examined by i-scan endoscopy and 39 patients were diagnosed with PHG by white light endoscopy. The strength of agreement between the two methods for the diagnosis of PHG was moderate (k=0.565; 95%CI 0.271-0.859; p<0.001). I-scan 1 classified the mosaic pattern better than classic endoscopy; i-scan 2 described better the red spots. Conclusion: I-scan examination increased the diagnostic sensitivity of PHG. The diagnostic criteria (mosaic pattern and red spots) were easier to observe endoscopically using i-scan than in white light.Abbreviations: FICE: Fuji Intelligent chromoendoscopy; GAVE: gastric antral vascular ectasia; NBI: narrow band imaging; PHG: portal hypertensive gastropathy; PHT: portal hypertension; UGIB: upper gastrointestinal bleeding.

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