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Author Topic: Help me with LEDs !  (Read 6251 times)

tonygiang

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Help me with LEDs !
« on: January 12, 2021, 03:54:35 AM »
Hi dear all !

I want help me on this forum that : Which type of LEDs both captures and emits the most efficient light? Thank you very much !

lancaIV

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Re: Help me with LEDs !
« Reply #1 on: January 12, 2021, 07:27:49 AM »
LED = light emitting diode
Light capturing diode = photo-diode

by an-ode to cath-ode current flow

Sincere
OCWL

AlienGrey

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Re: Help me with LEDs !
« Reply #2 on: January 12, 2021, 11:08:50 AM »
LED = light emitting diode
Light capturing diode = photo-diode

by an-ode to cath-ode current flow ! NO IT DOES NOT !

Sincere
OCWL
WHAT ??? Get a life so in a cathode ray tube your theory is electrons travel from the positive final anode to the cathode where
the heater is ! that would result in no picture !

In a thermionic valve the heater aids the emition of freeing electrons !  to travel to the Anode! ...... it's the same flow direction Diode.

HA HA HA!

lancaIV

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Re: Help me with LEDs !
« Reply #3 on: January 12, 2021, 11:14:36 AM »
WHAT ??? Get a life so in a cathode ray tube your theory is electrons travel from the positive final anode to the cathode where
the heater is ! that would result in no picture !

In a thermionic valve the heater aids the emition of freeing electrons !  to travel to the Anode! ......

HA HA HA!
https://www.autodesk.com/products/eagle/blog/diode-led-work/
negative HA HA HA ! ;)
From wesleys thread : Kapitsa-Dirac and de Broglie : the final countdown 'light-wave dualism ' theorem

light not wave=heat  ;D AG : your theme is thermo-voltaic or therm-ionic or thermo-acoustic related thermal noise

AlienGrey

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Re: Help me with LEDs !
« Reply #4 on: January 12, 2021, 11:20:17 AM »
Yes so why are you saying the opposite ?

lancaIV

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Re: Help me with LEDs !
« Reply #5 on: January 12, 2021, 11:23:25 AM »
Yes so why are you saying the opposite ?
https://en.wikipedia.org/wiki/Kapitsa%E2%80%93Dirac_effect
compared

https://www.autodesk.com/products/eagle/blog/diode-led-work/ 
Yes so why (are you: NO !) the autodesk article saying the opposite ?  ::)

 On a physical diode, you’ll notice two terminals extending from a tin can shape in the middle. One side is the positive terminal, called the anode. The other terminal is the negative end, called the cathode. Going back to our flow of electricity, current can only move in a diode from the anode to the cathode, never the other way around.

compared

storage polarisation !
https://www.autodesk.com/products/eagle/blog/wp-content/uploads/2017/04/2017-04-05_9-12-27-768x253.png


Sincere
OCWL

AlienGrey

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Re: Help me with LEDs !
« Reply #6 on: January 12, 2021, 11:58:24 AM »
Storage polarization is intellectual bull shit !

what it means is where the free electron has been leaves a hole
your talking about where they have been going the other way !

So if your walking forward where you have been is the past where you have been walking backwards !

a great philosophy your into !

lancaIV

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Re: Help me with LEDs !
« Reply #7 on: January 12, 2021, 12:09:41 PM »
At first : if philosophy works then this philosophy is right ! ;)


Seconds : there is the "ordinary" anode-cathode diode,definded, and the more specific diodes kinds !

When You look for the diode as n-p-n or p-n-p structure Ýou get solar or photo-electric cells or with wider emf bandgap thermovoltaic cells !

But here You need to define the spectrum between diode and transistor and function  :
https://en.wikipedia.org/wiki/Diode

https://en.wikipedia.org/wiki/Transistor

https://en.wikipedia.org/wiki/Photoelectric_effect

 https://www.toppr.com/ask/question/the-phenomenon-of-xray-production-is-basically-inverse-of-photoelectric/

https://en.wikipedia.org/wiki/Betavoltaic_device

beside photoelectric now completed by https://www.google.com/search?client=firefox-b-d&q=phonoelectric&nfpr=1&sa=X&ved=2ahUKEwjnsaGYopbuAhUHxBQKHcf_AKUQvgUoAXoECBwQNQ&biw=1366&bih=633
de Broglie + Plancksche Konstante ,Planksche Wirkungsquantum

lancaIV

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Re: Help me with LEDs !
« Reply #8 on: January 14, 2021, 07:13:27 AM »
in memoriam Gustav Pese I recommend in his "Show postes" Nr. 27 : the simple circuit
and
for later experiments www.phils.com.au/kron.htm related " negative resistor" !
Between Peses postes Nr.1-27 is something,more redundant,as overview, about the in-/out-put effect to read.
Non hertzian wave energy (searchmachine : cold energy )

About LEDs and their functionality related official 100 000 hours work duration and real life experience a professional ex-Phillips engineer told me that the resistors connection is the problem !

Related 'non hertzan wave' and the autodesk-article 1diode and 4 diodes circuit scheme ,wth ONLY positive voltage output,the inverse way : ONLY negative voltage delivered as ambiental energy converter by sympathetic resonance !

Between 0° C and 0° K are 273 pressure/force degrees energy !

One the way to monopolar attraction or monopolar repulsion : radar/stealth !

Thermograph/Thermoacoustic : fingerprint with timesequence controle forward/afterward :Phantom/Tarnkappe

          real/virtual         Zeit-/Raum displacement/beam technology ( Gulliver macro/micro dilatation principle)



Sincere
OCWL

AlienGrey

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Re: Help me with LEDs !
« Reply #9 on: January 14, 2021, 08:17:03 AM »
When quoting other peoples so called statements as actual facts and when one hasn’t bothered to proved or tested ones self could be misleading to others or as missing modern descriptive key words or plain wrong.
This practice can often lead to a waste of material or damage to expensive components going up in smoke if replicated!

Lets for instance look at the positive and negative temperature 'coefficient' terminology

Both of these type of devices were used early on to demagnetise the old shadow mask tube as it's 'mask'
was made of a ferrous magnetic material, I would suggest if your going to use 'quotes' by others you should use an up to date terminology and thus prove or show with a diagram how it works.

Also results I found for negative resistance coefficient.
A negative coefficient for a material means that its resistance decreases with an increase in temperature.

Semiconductor materials (carbon, silicon, germanium) typically have negative temperature coefficients of resistance.

SIL


Floor

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Re: Help me with LEDs !
« Reply #10 on: January 15, 2021, 12:37:17 AM »
https://www.allaboutcircuits.com/textbook/direct-current/chpt-1/conventional-versus-electron-flow/

Positive and Negative Electron Charge
When Benjamin Franklin made his conjecture regarding the direction of charge flow (from the smooth wax to the rough wool), he set a precedent for electrical notation that exists to this day, despite the fact that we know electrons are the constituent units of charge, and that they are displaced from the wool to the wax—not from the wax to the wool—when those two substances are rubbed together. This is why electrons are said to have a negative charge: because Franklin assumed electric charge moved in the opposite direction that it actually does, and so objects he called “negative” (representing a deficiency of charge) actually have a surplus of electrons.
By the time the true direction of electron flow was discovered, the nomenclature of “positive” and “negative” had already been so well established in the scientific community that no effort was made to change it, although calling electrons “positive” would make more sense in referring to “excess” charge. You see, the terms “positive” and “negative” are human inventions, and as such have no absolute meaning beyond our own conventions of language and scientific description. Franklin could have just as easily referred to a surplus of charge as “black” and a deficiency as “white,” in which case scientists would speak of electrons having a “white” charge (assuming the same incorrect conjecture of charge position between wax and wool).
Conventional Flow Notation
However, because we tend to associate the word “positive” with “surplus” and “negative” with “deficiency,” the standard label for electron charge does seem backward. Because of this, many engineers decided to retain the old concept of electricity with “positive” referring to a surplus of charge, and label charge flow (current) accordingly. This became known as conventional flow notation:

Electron Flow Notation
Others chose to designate charge flow according to the actual motion of electrons in a circuit. This form of symbology became known as electron flow notation:

In conventional flow notation, we show the motion of charge according to the (technically incorrect) labels of + and -. This way the labels make sense, but the direction of charge flow is incorrect. In electron flow notation, we follow the actual motion of electrons in the circuit, but the + and - labels seem backward. Does it matter, really, how we designate charge flow in a circuit? Not really, so long as we’re consistent in the use of our symbols. You may follow an imagined direction of current (conventional flow) or the actual (electron flow) with equal success insofar as circuit analysis is concerned. Concepts of voltage, current, resistance, continuity, and even mathematical treatments such as Ohm’s Law (chapter 2) and Kirchhoff’s Laws (chapter 6) remain just as valid with either style of notation.
Conventional Flow Notation vs Electron Flow Notation
You will find conventional flow notation followed by most electrical engineers, and illustrated in most engineering textbooks. Electron flow is most often seen in introductory textbooks (this one is moving away from it, however) and in the writings of professional scientists, especially solid-state physicists who are concerned with the actual motion of electrons in substances. These preferences are cultural, in the sense that certain groups of people have found it advantageous to envision electric current motion in certain ways. Being that most analyses of electric circuits do not depend on a technically accurate depiction of charge flow, the choice between conventional flow notation and electron flow notation is arbitrary . . . almost.
Polarization and Nonpolarization
Many electrical devices tolerate real currents of either direction with no difference in operation. Incandescent lamps (the type utilizing a thin metal filament that glows white-hot with sufficient current), for example, produce light with equal efficiency regardless of current direction. They even function well on alternating current (AC), where the direction changes rapidly over time. Conductors and switches operate irrespective of current direction, as well. The technical term for this irrelevance of charge flow is nonpolarization. We could say then, that incandescent lamps, switches, and wires are nonpolarized components. Conversely, any device that functions differently on currents of different direction would be called a polarized device.
There are many such polarized devices used in electric circuits. Most of them are made of so-called semiconductor substances, and as such aren’t examined in detail until the third volume of this book series. Like switches, lamps, and batteries, each of these devices is represented in a schematic diagram by a unique symbol. As one might guess, polarized device symbols typically contain an arrow within them, somewhere, to designate a preferred or exclusive direction of current. This is where the competing notations of conventional and electron flow really matter. Because engineers from long ago have settled on conventional flow as their “culture’s” standard notation, and because engineers are the same people who invent electrical devices and the symbols representing them, the arrows used in these devices’ symbols all point in the direction of conventional flow, not electron flow. That is to say, all of these devices’ symbols have arrow marks that point against the actual flow of electrons through them.
Perhaps the best example of a polarized device is the diode. A diode is a one-way “valve” for electric current, analogous to a check valve for those familiar with plumbing and hydraulic systems. Ideally, a diode provides unimpeded flow for current in one direction (little or no resistance), but prevents flow in the other direction (infinite resistance). Its schematic symbol looks like this:

Placed within a battery/lamp circuit, its operation is as such:

When the diode is facing in the proper direction to permit current, the lamp glows. Otherwise, the diode blocks current flow just like a break in the circuit, and the lamp will not glow.
If we label the circuit current using conventional flow notation, the arrow symbol of the diode makes perfect sense: the triangular arrowhead points in the direction of charge flow, from positive to negative:

On the other hand, if we use electron flow notation to show the true direction of electron travel around the circuit, the diode’s arrow symbology seems backward:

For this reason alone, many people choose to make conventional flow their notation of choice when drawing the direction of charge motion in a circuit. If for no other reason, the symbols associated with semiconductor components like diodes make more sense this way. However, others choose to show the true direction of electron travel so as to avoid having to tell themselves, “just remember the electrons are actually moving the other way” whenever the true direction of electron motion becomes an issue.
Should You Use Conventional Current Flow or Electron Flow?
Both models will produce accurate results if used consistently, and they are equally “correct” insofar as they are tools that help us to understand and analyze electric circuits. However, in the context of electrical engineering, conventional current is far more common. This textbook uses conventional current, and anyone who intends to study electronics in an academic or professional environment should learn to naturally think about electric current as something that flows from higher voltage to lower voltage.”

AlienGrey

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Re: Help me with LEDs !
« Reply #11 on: January 15, 2021, 08:38:22 AM »
Question have you read the question at the start of the tread ?

SIL

lancaIV

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Re: Help me with LEDs !
« Reply #12 on: January 15, 2021, 08:53:53 AM »
Yes,AG(SIL),but it is a 'conduction' related question and the right answer would be not a LED but for example ' glas-fiber' !
Sincere
OCWL

ALVARO_CS

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Re: Help me with LEDs !
« Reply #13 on: January 15, 2021, 10:20:21 AM »
https://www.allaboutcircuits.com/textbook/direct-current/chpt-1/conventional-versus-electron-flow/
On the other hand, if we use electron flow notation to show the true direction of electron travel around the circuit, the diode’s arrow symbology seems backward:
And to add to the confussion in the same page:

lancaIV

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Re: Help me with LEDs !
« Reply #14 on: January 15, 2021, 10:36:11 AM »
Behaviour as individual element ,as element part in a network/array/circuit !

Under defined "hot/cold"- condition,specific materials their specific values !
Insulator to semi-conductor to full conductor by switch ,internal or external !

New science : Meta-material/-s ,new amalgams/elementar mixture

Intelligence inside materials,self-aligning,self-optimizing by ' natural random generator'

Because this "quantum computering" is magnitudes faster and  smaller in comparison to analog circuits !

Digital circuits/array/network ! Digital neuronal-brains ! Light velocity versus terrestric human body velocity !


Pioneers in digital EE : Gabriel Kron,,John von Neumann ; Modulator,Analyzer,Comparator

High/low/no positive resistance to no/low/high negative resistance

Supraconduction to light velocity to ≥ light velocity like space shuttle-Jumbo 747 start  (light velocity) v X




Sincere

OCWL