Light emitting diodes (LEDs) are semiconductor devices that convert electrical energy into monochromatic light. LEDs have a p-n junction consisting of two types of semiconducting materials. When voltage is applied across the junction, electrons can flow from the n-type to the p-type material, recombining with holes and releasing energy in the form of photons. LEDs are available in different colors depending on the semiconductor material and come in single-color, bi-color, and tri-color varieties. They have applications in sensors, displays, lighting, and automotive and traffic signals due to their energy efficiency and long lifetime.
this is presentation about light emitting diode. it includes it working, figure and application. also shows the live example of led. it also contains its preference website..
any changes suggested are welcomed..
this is presentation about light emitting diode. it includes it working, figure and application. also shows the live example of led. it also contains its preference website..
any changes suggested are welcomed..
hey guyz this is the presentation iv made in my last year of engineering and got very nice feedbacks. my topic was oled(organic light emitting diodes).. iv given all its highlited informations with pictures
This Presentation most beneficial for Engineering student and mostly for electronics.In this PPT discuss about the led and also how does it work , use and also discuss about construction of LED,color material,cost , application and many more
A light-emitting diode (LED) is a semiconductor light source that emits light when a current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the bandgap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.
Detail slides on LED Display. Every major thing related to LED is discussed in this topic. Like History, Inventor, Types, Drawbacks of displays, 3D TVs etc
Organic Light Emitting Diode or OLED
An OLED is a solid state device or electronic device that typically consists of organic thin films sandwiched between two thin film conductive electrodes. When electrical current is applied, a bright light is emitted. OLED use a carbon-based designer molecule that emits light when an electric current passes through it. This is called electrophosphorescence. Even with the layered system, these systems are thin . usually less than 500 nm or about 200 times smaller than a human hair.
hey guyz this is the presentation iv made in my last year of engineering and got very nice feedbacks. my topic was oled(organic light emitting diodes).. iv given all its highlited informations with pictures
This Presentation most beneficial for Engineering student and mostly for electronics.In this PPT discuss about the led and also how does it work , use and also discuss about construction of LED,color material,cost , application and many more
A light-emitting diode (LED) is a semiconductor light source that emits light when a current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the bandgap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.
Detail slides on LED Display. Every major thing related to LED is discussed in this topic. Like History, Inventor, Types, Drawbacks of displays, 3D TVs etc
Organic Light Emitting Diode or OLED
An OLED is a solid state device or electronic device that typically consists of organic thin films sandwiched between two thin film conductive electrodes. When electrical current is applied, a bright light is emitted. OLED use a carbon-based designer molecule that emits light when an electric current passes through it. This is called electrophosphorescence. Even with the layered system, these systems are thin . usually less than 500 nm or about 200 times smaller than a human hair.
[cliente: AUTOSSUSTENTÁVEL]
Apresentação institucional elaborada para a Rede Autossustentável, uma rede de informações que tem por objetivo compartilhar e multiplicar informações e práticas socioambientais.
Eurostat a publié, le 26 octobre 2016, un communiqué de presse sur les caractéristiques de la démographie des entreprises de l'UE.
Eurostat révèle que quasiment 1 entreprise sur 10 dans l'UE est considérée comme société à forte croissance.
Les secteurs des services enregistrent les pourcentages les plus hauts.
Eurostat précise qu'en 2014, environ 145.000 entreprises, soit 9,2% (un dixième) de l'ensemble des entreprises actives de l'économie marchande employant au moins 10 salariés dans l'UE ont été reconnues comme sociétés à forte croissance.
Les plus fortes proportions d'entreprises à forte croissance ont été enregistrées à Malte, au Royaume Uni et en Lettonie.
creare un clima all’interno dell’organizzazione basato sulla fiducia e acquisire credibilità;
sviluppare l’approccio migliore per i diversi contesti e interlocutori dell’organizzazione;
rendere i processi più efficienti e fare un uso più oculato delle risorse;
elaborare un piano di sviluppo del proprio gruppo di lavoro, monitorandone efficacia e qualità.
Frauen in Führungspositionen - gelebter Alltag oder noch Zukunftsvision? Wir beleuchten die Berufschancen im Geschlechter-Vergleich und zeigen, wo heutzutage Jobs gesucht und gefunden werden.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
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New development in herbals,
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Reverse Pharmacology.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
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The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2024.06.01 Introducing a competency framework for languag learning materials ...
LED (LIGHT EMITTING DIODE)
1. LIGHT EMITTING
DIODES
PRESENTED BY –
NEERAJ KUSHWAHA
(07)
PIYUSH YADAV (16)
SACHIN KR. DIXIT (50)
SACHIN SHARMA (53)
SAJAL RAWAT (55)
2. WHAT IS A LIGHT-EMITTING DIODE (LED)?
A DEVICE THAT CONVERTS ELECTRICAL ENERGY
INTO LIGHT .
A P-N JUNCTION DIODE THAT EMITS
MONOCHROMATIC LIGHT WHEN FORWARD BIASED.
3. ABOUT LEDS
3
•The most important part of a light emitting diode (LED) is the semi-
conductor chip located in the center of the bulb as shown at the right.
•The chip has two regions separated by a junction.
•The junction acts as a barrier to the flow of electrons between the p
and the n regions.
4. HOW DOES A LED WORK?
4
•When sufficient voltage is applied to the chip
across the leads of the LED, electrons can move
easily in only one direction across the junction
between the p and n regions.
•When a voltage is applied and the current starts
to flow, electrons in the n region have sufficient
energy to move across the junction into the p
region.
5. HOW DOES A LED WORK?
5
•Each time an electron recombines with a
positive charge, electric potential energy
is converted into electromagnetic energy.
•For each recombination of a negative and a
positive charge, a quantum of electromagnetic
energy is emitted in the form of a photon of
light with a frequency characteristic of the
semi-conductor material
6. HOW MUCH ENERGY DOES AN LED
EMIT?
6
•The energy (E) of the light emitted by an LED is related to the electric
charge (q) of an electron and the voltage (V) required to light the LED by
the expression: E = qV Joules.
•This expression simply says that the voltage is proportional to the
electric energy
•The constant q is the electric charge of a single electron, -1.6 x 10-19
Coulomb.
7. FINDING THE ENERGY FROM THE
VOLTAGE
7
•Let us say that you have a red LED, and the voltage measured between
the leads of is 1.71 Volts. So the Energy required to light the LED is
E = qV or E = -1.6 x 10-19 (1.71) Joule,
•since a Coulomb-Volt is a Joule. The Product of these of numbers then
gives
E = 2.74 x 10-19 Joule.
8. COLOURS OF LEDS
8
•LEDs are available in red, orange, amber, yellow, green, blue and white.
• LEDs are made from gallium-based
crystals that contain one or more
additional materials such as phosphorous
to produce a distinct color.
• Different LED chip technologies emit
light in specific regions of the visible
light spectrum and produce different
intensity levels.
9. Tri-colour LEDs
•The most popular type of tri-colour LED has a red and a
green LED combined in one package with three leads..
•There are different lengths of the three leads.
10. LED PERFORMANCE
10
Colour
•Peak wavelength is a function of the LED chip material. Although
process variations are ±10 NM, the 565 to 600 NM wavelength
spectral regions is where the sensitivity level of the human eye is
highest. Therefore, it is easier to perceive color variations in yellow
and amber LEDs than other colors.
11. LED PERFORMANCE
White Light
• When light from all parts of the visible spectrum overlap one
another, the additive mixture of colors appears white.
• Primary colors from the upper, middle, and lower parts of the
spectrum (red, green, and blue), when combined, appear white.
11
