Led Composition

In: Science

Submitted By ajm0523
Words 1485
Pages 6
Section 1:
Claim:
Observable factors that affect the composition of LEDs

During our research of gallium arsenide phosphide (GaPxAs1-x), which is a semi-conducting material in the form of light emitting diodes, we observed how properties of the data collected directly correlated to the composition of the LED. The observed and measured properties we were able to notice and calculate during our research were wavelength, color, voltage, and temperature. Using a diffraction grating we first tested the different compositions for which color of light was emitted. Our data as can be seen in appendix 1, on pg. L93 table 1, shows that as the composition shifted from GaP0.40As0.60 to GaP1.00As0.00 the colors emitted, shifted from those associated with longer wavelengths to those of shorter wavelengths. (Red to green) We then set up a scanning spectrometer in order to measure the wavelengths, and as can be seen in our data in appendix 1, on pg. L94 table 2, as well as on the graph in appendix 2, we were able to measure the wavelength of each LED with varying composition. According to our data it can be said that greater bond length equals lower Eg, since lower Eg will result in longer wavelength. For example, GaP1.00As0.00 has the shortest wavelength and the shortest bond length, and as a result has the largest band gap energy. From the same data we can also conclude that greater bond strength equals greater Eg due to the fact that GaP1.00As0.00 has the highest bond strength. The reason for this is because phosphorus has a shorter atomic radius then arsenic, allowing the length of the unit cell edge to decrease, enhancing the orbital overlap, which results in greater Eg. We then measured the voltage out put of each LED composition and as can be seen from our data in appendix 1, on pg. L94 table 3. As the composition shifted from higher levels arsenic to phosphorus we saw…...

Similar Documents

Composition

... GE217 Composition II Week 2 (B) Identifying logical Fallacies 1. Bandwagon Appeal: “Cash for Clunkers”; The New York Times, September 30, 2012 The argument on this article is about how the people think that something should to be done because the majority does it. The "Cash for Clunkers" program has been a success. By subsidizing the purchases of new, more fuel efficient vehicles for Americans willing to trade in their old gas guzzlers, this initiative makes a short-term investment in our long-term goals of environmental protection and decreasing our dependence on fossil fuels. 2. Ad Hominem: The education for women; Richard Norquist; This is an article from the year 1917 were women are not suppose to know everything like men, he’s argument and appeal that women should have the right to go be equal to men in terms of education. 3. Begging the question: “Murder is morally wrong, Therefore, abortion is morally wrong”;Hurley P. ; About.com The argument presumes the truth of a premise that isn’t stated, namely that abortion is murder. As this premise is far from obvious, and the arguer doesn’t even mention it (much less give it a defense), the argument begs the question. 4. Red Herring: Consequences of using Nuclear Power; Dean Babst and David Krieger; 1997 Here the arguer does nothing to address the issue of the dangers of nuclear power, but instead changes the subject to the danger of electricity. If there’s even an argument at all here, it certainly has nothing......

Words: 432 - Pages: 2

Led 8x8x8

...Photo Ride Science Tech LED Cube 8x8x8 by chr on November 16, 2010 Table of Contents LED Cube 8x8x8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Intro: LED Cube 8x8x8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Step 1: Skills required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Step 2: Component list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . File Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Step 3: Ordering components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Step 4: What is a LED cube . . . . . . . .......

Words: 21520 - Pages: 87

Led Calculation

... This tutorial will help you to find the proper value of resistor (or resistors) for one or more LED’s to connect with battery.  If you pick this topic, you will be able to: Calculate the value of resistors for different LED’s Circuit diagrams Calculate the Forward Current of LED’s Calculate the Forward Voltage for different LED’s Circuits Connect LED’s in Series with batter Connect LED’s in Parallel with battery Connect LED’s in Series-Parallel Circuits Typical LED Symbol, Construction and Lead Identification.                                                Click Image to enlarge Before we go in detail, we will try to get ride on below simple circuit, so that the other calculation will be easier to understand.                                                  Click Image to enlarge This is the Simplest LED Series circuit ever. Here, the supply voltage is V, LED Forward Voltage (VF) is 1.3 Volt and Forward Current (IF) is 10mA. Now the Value of resistor (which we will connect in Series with LED) for this circuit would be: Resistor Value = (Vsupply - VF)/ IF = (6 -1.3) / 10mA = 470 Ω Current draw = 20mA Resistor Power rating formula for this circuit Resistor Power Rating = IF2 x Resistor Value = (10mA) 2 x 470 Ω = 0.047W = 47mW But This is the minimum required resistor value to ensure that resistor will not overheat, so its recommended that to double the power rating of resistor that you have calculated, therefore, choose 0.047W x 2 = 0.094W = 94mW......

Words: 1340 - Pages: 6

Led Lights

...LED LIGHTS A Museum Exhibit Case Study By John Miles June 06, 2014 In April 2014, the Durango County Museum of History installed a small exhibit titled Our heritage: Pictures from the past. The collection consists of five daguerreotypes and several silver albumen prints. A study was made to measure the benefits and costs of using LED lights instead of traditional halogen lamps. RISKS OF LIGHTING HISTORIC PHOTOGRAPHS All lighting harms photographs. (Lavedrine 2003) It is the task of the conservator to minimize this harm so that the photographs can be viewed for a significant span of time, typically 50 to 100 years. For these reasons, historical photographs are displayed only periodically in rooms with significantly reduced lighting. These practices minimize the visitor experience and according to Hunt, reducing light levels diminishes color saturation and contrast. (Hunt 1952, 192) In all lighting systems, ultraviolet light (UV) must be eliminated as that spectrum harms photographs the most. Halogen lights must have UV filters installed which adds to their cost and effectiveness. LED lamps do not emit UV light and do not need extra filters. According to a study by the Getty Conservation Institute, fading from LED lamps does not result in any more damage than conventional halogen lamps with ultraviolet filtering. They found that it is likely using LED lamps results in less fading of photographic materials. (Druzik and Miller 2011) METHODOLOGY In the new exhibit, 12......

Words: 715 - Pages: 3

Led and Photodiode

...behind the working of LED is electroluminescence. The Light emitting diode should be forward biased to get the light. In Light emitting diodes, electrons are injected from low work function cathode to the conduction band of the n-type semiconducting material and holes are injected from high work function anode to the valence band ot the p-type semiconducting material. When the electron in the conduction band combines with the hole in the valence band, energy is released. In case of indirect band gap semicondutors, phonon will be released to conserve of both energy and momentum. But in case of direct band gap semiconductor, light will be emitted whose wavelength depends on the band gap of the semiconductor. Different parts of a Light emitting diode Radiative recombination in direct and indirect bandgap semiconductor Cartoon showing radiative recombination in a direct band-gap semiconductor Schematic diagram of working of an LED Light emitting Diode and its circuit symbol The main advantage of Light emitting diode over other light sources is its increased efficiency. LEDs are available in red,......

Words: 507 - Pages: 3

Composition and Inverse

...Composition and Inverse Alicia Frambro MAT 222: Intermediate Algebra Prof: Michael Smith September 22, 2013 Composition and Inverse When using functions, there are different ways to solve various values. Many companies use these functions to monitor business pertaining gross profit and many other operations such as adjusting productivity. Visual examples of these functions are graphs. They provide a visual relationship between composition and inverse solutions as well and the difference between profit gain and profit loss for a business. The following functions will be used to solve certain problems. fx=2x+5 g(x)=x2-3 (x) = 7+x3 f-h(4) Use rule of composition and solve which is f(4)-h(4). f(x)-h(x)= 2x+5-(7-x) 2(4) +5- 7-43 Substitute 4 for x. 8+ 5- 33 Use order of operations to solve. 8+5-1= 12 Therefore (f-h)(4)= 12 Evaluate two compositions of the above functions. A. (fog)(x) B. (fog)(x) The method that should be used to solve is to find the solution of one function and then substitute the solution for x in the other solution. For A we would first solve for g(x) and substitute the solution for x into f(x). A. (fog)(x)= f(g(x)) (fog)(x)= f(x2-3) (fog)(x)= 2(x2-3) +5 Substitute g(x) for x in f(x). (fog)(x) = 2x2-6+5 Simplify by using the distributive property and order of operations. (fog)(x)= 2x2 -1 Answer. B. (h0g)(x) = h(g(x)) Use the same concept of A but (hg)(x)= h(g(x)) (hog)(x) = h(x2 –......

Words: 660 - Pages: 3

Composition

...car because she had a couple errands to run and that I am to come straight home after class. Well, being the person that I was at the time, “hard headed, mischievous, and basically thought I was grown,” I had my own priorities I wanted to handle before going home. So immediately after class I called up one of my buddies and asked him if he wanted to go joy-riding and pick up a couple females. He replied yes and that’s all the motivation I needed to say forget what my mom said, I’m going to enjoy myself today….BECAUSE IT’S FRIDAY AND I DIDN’T HAVE TO WORK…What! So I picked my buddy up as soon as class was over. We called some females and told them we would stop by to see them once we finish with our first plans. Now comes the fun part….. Led up: Tickets and accidents During this whole ordeal, even though I was told to come straight home, I totally disobeyed my mom. She call my phone numerous times but I neglected to answer. Due to the event that transpired, have you ever heard of karma….Well as for me she became a real pain in the butt. My buddy and I stopped at a package store and grabbed some alcohol so we could have a couple drinks with the ladies. While we were there we ran into another one of my close friends who I also invited to ride along. Now it’s me, two of my buddies, a bottle of alcohol, a pack of corona, and the open road. I was just asking for trouble and little did I know it would find me around the next corner. Because my friends were in the car I decide to......

Words: 857 - Pages: 4

Composition

...counselors and cheerleaders. Rafe Sagalyn and Cyrille Gorin were mine, urging me to write this book in the first place and helping me to get started. Melinda Merino has been the consummate editor. Her judgment and support have made this a better book. Lastly, special thanks go to my husband, Bill Magretta. This isn’t the obligatory spousal thankyou-for-putting-up-with-me. Bill is, and always has been, my secret weapon, the smartest reader I know. Introduction MICHAEL PORTER DIDN’T GET to be a giant in the field of competition and strategy by hunting small game. Very early in his career, he went after the single biggest and most consequential question in business: Why are some companies more profitable than others? One big question led to another. Why are some industries consistently more profitable than others, and what does this mean for the manager developing a strategy? Why are some countries or regions more successful than others, and what does this mean for companies in a global era? Since the publication of his groundbreaking classics, Competitive Strategy (1980) and Competitive Advantage (1985), Michael Porter has been steadily building answers to these fundamental questions about competition and competitive success. What could be more important for managers? The thing about classics, as Mark Twain once observed, is that they are often books “that everybody wants to have read and nobody wants to read.” Tackling Porter’s work can be a bit like undertaking a......

Words: 59071 - Pages: 237

Composition of Sugars

...Lab: 3—Chemical Composition of Cells: Sugars Purpose of this lab: To learn about sugars and the test used to identify them. Introduction The organic macromolecules known as sugars are a type of carbohydrate. Carbohydrates are composed of monosaccharides, which are single, sugar unit monomers. Two sugar units linked together are known as a disaccharide. In this lab, we conducted tests on various substances with Bendict’s solution to determine which sample contained sugars. Benedict’s solution is a turquoise blue color and reacts with sugars after being heated in a boiling water bath, resulting in a color change. The color change varies with the concentration of sugar present, with strong positives indicating a high sugar concentration and weaker positives correlating with lesser concentrations of sugar. The color changes are as follows: orange-red (very high), orange (high), yellow-orange (moderate), yellow (low), green (very low), no change in color (no sugar present). Materials and Methods: --6 test tubes marked at 1cm and 3cm from the bottom --Benedict’s reagent --substances to be tested: water (control), glucose solution, onion juice, potato juice, starch suspension, and an unknown substance --hot plate with a beaker filled with water for a boiling water bath Each substance to be tested was filled in a separate test tube to the 1cm mark, with the exception of onion and potato juice, to which 5 drops of each were added to......

Words: 475 - Pages: 2

Composition Reflection

...read and understood the Notice to Candidate (above). I have produced the attached work without assistance other than that which my teacher has explained is acceptable within the specification. Candidate’s signature: …………………………………………………………… Date: ………………………… Composition 1 (Western Classical Tradition) – Title: Stimulus (to be completed by candidate). | General details of composing (to be completed by candidate). Include exact details of how composing software was used (samples/loops/use of arrangement facility, etc). For live performances candidates must provide exact details of their individual contribution during the recording process. | SUPERVISION AND MONITORING: Composition 1 (Western Classical Tradition).The following three sections are to be completed by the candidate and countersigned by the teacher during the composition process to show development and progress. | CHECK 1Describe the planning and opening draft, including any advice received during the initial stages of the composition. | Teacher signature: Date: | CHECK 2Explain the process of composition during the developmental stages of the piece, including the nature of any help or advice received. | Teacher signature: Date: | CHECK......

Words: 1042 - Pages: 5

Document Composition

...variants of β-casein have a Histidine residue at this position. In the case of the variants containing Proline the enzymatic hydrolysis of the Ile66-Pro67 bond does not occur or occurs at a very low rate. The proportion of the different protein variants expressed in the milk, including those of βcasein, is related to their allele distributions in the various cattle breeds and populations. Changing selection targets in the last decades has resulted in changes in bovine breed EFSA Scientific Report (2009) 231, 2-107 Review of the potential health impact of β-casomorphins and related peptides composition in most European countries. While no detailed information is available, it is likely that these changes in breed composition have had an impact on milk composition, including protein variants. Taking into account the lack of detailed knowledge in milk protein variant composition and the diverse geographical origin of dairy products and ingredients across Europe, insufficient information is currently available on the exposure of individual consumers to different β-casein variants. It would appear that fresh raw/unprocessed milk obtained from healthy cows does not contain BCM7 or related peptides. By contrast, there is a substantial body of evidence indicating that different proteolytic systems involved in fermented milk or cheese manufacture can potentially hydrolyze β-casein to BCM7 or other BCMs and further degrade these peptides to shorter-chain peptides and even......

Words: 50772 - Pages: 204

Composition

...Composition 1.1 Felipe Viveiros de Moura PAT 201 1. “Creaking Door” a. Where and when: This creaking door was recorded on Wednesday, 13th of January in my house located in South State Street. b. Interest and influence: Having lived in this house for about 5 months, the creaking of my door every time I leave my room has become a sound that is part of my daily routine. After listening to all my recordings and selecting the top 8, this was one of the ones that, I believe, captured exactly what I was looking for. c. Techniques: Mic of the recorder was placed very close to the axis of rotation of the door d. Success in capturing sound: For a couple of tries, I could not capture the sound as loud as I intended to. After changing position, recording from inside the room and increasing the recording level, I was able to get the results I wanted. Background sound from my roommates was another difficulty but recording from inside the room helped solve the problem. 2. “Flush” e. Where and when: The flush of a toilet was recorded on Wednesday, 13th of January in my house located in South State Street. f. Interest and influence: Although this is a sound that everyone listens to every day, it does not receive the appreciation that it deserves due to its bad association. g. Techniques: recorder was placed perpendicular to the toilet centered in the drainage, to avoid the sound being too loud I made sure to place the recorder......

Words: 1157 - Pages: 5

Led Lights

...LED LIGHTS A Museum Exhibits Case Study By Deric Payne December 3, 2014 In April 2014, the Durango County Museum of History installed a small exhibit titled Our heritage: Pictures from the past. The collection consists of five daguerreotypes and several silver albumen prints. A study was made to measure the benefits and costs of using LED lights instead of traditional halogen lamps. RISKS OF LIGHTING HISTORIC PHOTOGRAPHS All lighting harms photographs. (Lavedrine 2003) It is the task of the conservator to minimize this harm so that the photographs can be viewed for a significant span of time, typically 50 to 100 years. For these reasons, historical photographs are displayed only periodically in rooms with significantly reduced lighting. These practices minimize the visitor experience and according to Hunt, reducing light levels diminishes color saturation and contrast. (Hunt 1952, 192) In all lighting systems, ultraviolet light (UV) must be eliminated as that spectrum harms photographs the most. Halogen lights must have UV filters installed which adds to their cost and effectiveness. LED lamps do not emit UV light and do not need extra filters. According to a study by the Getty Conservation Institute, fading from LED lamps does not result in any more damage than conventional halogen lamps with ultraviolet filtering. They found that it is likely using LED lamps results in less fading of photographic materials. (Druzil and Miller 2011) METHODOLOGY In the new exhibit,...

Words: 714 - Pages: 3

Led Light

...A light-emitting diode (LED) is a two-lead semiconductor light source. It is a p–n junction diode, which emits light when activated.[4]When a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor. An LED is often small in area (less than 1 mm2) and integrated optical components may be used to shape its radiation pattern.[5] Appearing as practical electronic components in 1962,[6] the earliest LEDs emitted low-intensity infrared light. Infrared LEDs are still frequently used as transmitting elements in remote-control circuits, such as those in remote controls for a wide variety of consumer electronics. The first visible-light LEDs were also of low intensity, and limited to red. Modern LEDs are available across the visible,ultraviolet, and infrared wavelengths, with very high brightness. Early LEDs were often used as indicator lamps for electronic devices, replacing small incandescent bulbs. They were soon packaged into numeric readouts in the form of seven-segment displays, and were commonly seen in digital clocks. Recent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer......

Words: 5486 - Pages: 22

Composition

...Analog/Digital Laboratory (or AT-800 Modular Lab, AT-701 Personal Lab) 2. 7404(NOT), 7408(AND), 7432(OR) Circuit Diagram: [pic] [pic][pic][pic] Procedure: Step 1: Find out correctly the input and output pin numbers of each gate. Step 2: Install the components of Fig 1-1 onto the breadboard of AT-700 and check properly the connections. Remember to connect each IC’s pin 14 to “+5V” of DC power supply of AT-700 and pin 7 to “GND”. Step 3: Connect the Data switches “0” and “1” to point A and B of fig. 1-1 respectively. Then connect 8 bit LED Display’s “0”, “1” and “2” to the output of point Y1, Y2 and Y3 of Fig. 1-1 respectively. The connection diagram is as follows. [pic] Step 4: Change Data Switches “0” and “1” between “0” and “1” position and observe the situation of 8 bit LED Display “0”, “1” and “2”. The LED is light that indicates the output is in the logic 1 condition. When LED is dark, it indicates that the output is in the logic 0 condition. Step 5: Record the results that you have observed into the truth table as follows. Truth Table 1-3 [pic] Discussion & Conclusion: (On the basis of experimental results)...

Words: 263 - Pages: 2