Today's entry is a guest blog by the renowned and internationally recognized OLED expert and journalist Dennis McCarthy. He is taking us on a journey through the world of OLED related acronyms - the words that many use but not everyone knows what is actually behind them. How good is your OLED knowledge?
In the lighting business these days there are plenty of them!
In the universe of lighting and all it entails these days, there are an abundance of these terms and abridgements. Why? Because it's the norm to shorten those lengthy multi term descriptions to a more manageable expression of what is there. We're in an age of IT and the Internet of Things (IoT). For those of us involved in lighting we all know of SSL. Those solid state wares can be LEDs or Electroluminescent Lights (EL), and among that LED designation there are so many subset variations. LEDs, as I presume you know, stands for Light emitting diodes. So, LEDs can be a group within a group; they can be OLEDs Organic LED or they could be ILED products, meaning inorganic LEDs. Typically that is the LED tech referred to as conventional LEDs. Since this audience is interested in OLED related things I rounded up a few dozen of my favorite OLED acronyms. Some apply to the LED wares with a lumpy topography but the premise is that most of those that follow are OLED-centric acronyms. You may even learn one or two that you haven't come across before.
There are types of OLEDs, or classes of them:
PASSIVE MATRIX /PMOLEDS are seen frequently in health tracking wearables, ie. a FITBIT. Active Matrix OLEDs are the type frequently seen by consumers these days. Many smartphones are using these AMOLEDS, with makers of display screens using AMOLEDS on everything from cameras to Smart watches to automobiles brake lights to giant OLED TVs.
There are OLED traits that get proclaimed in these acronyms:
- TOLEDs - These are those remarkable Transparent OLEDs.
- PhOLEDs - These are OLEDs using Phosphorescent light emitters in them.
- Those PLEDs that are out there are a variants of POLYMER LEDs.
- QLEDs / QD-OLEDs are ones that use Quantum Dots in their constructs.
- WOLEDs have a unique proprietary white emission arrangement.
- FOLEDs can refer to FLEXIBLE OLEDs as well as the newer FOLDABLE versions.
On to a different facet. There are variations of LEDs that are OLED-like such as OLETs (Organic Light Emitting Transistors) which use Transistors in lieu of Diodes. OLECs are a different animal indeed. They are Organic and they are LIGHT Emitting Chemical Cells, aka electro-Luminescent light emitting cells. There is even a "new to me" variation known as a OLEV. The V indicates that they use a varistor instead of a transistor or diode.
Regarding the OLED as a structure, not surprisingly there are acronyms that define the architectural structure. There are compound words that list out the metals used within a layers' constructs. Here are a couple for your edification or bemusement:
- ITO – Is one you should know of as virtually everyone of us has some product using ITOs. Do you have a phone, watch, dashboard or camera nearby? ITO stands for INDIUM TIN OXIDE and it's used in OLED Backplanes (real flat CPUs)
- IGZO – IF you were good in your chemistry classes years ago you might be able to figure it out. It's INDIUM GALLIUM_ZINC OXIDE and it's increasingly used as a backplane component too ... and it's fun to say IGZO ... IG ZO!
- LTPS - A Low Temperature Poly Silicone product. It's a bit less illlerative but is a substrate with a compound name where you can see why an acronym is apt.
- There are also TFTs or O- TFTs. These refer tothe constructs in all OLED_OLEPs. TFT Is the acronym for THIN FILM TRANSISTOR (O~sometimes they're organic). Again they play a role, like an electric neural network for light emitters/ pixels.
- TADF – stands for a THERMALLY ACTIVATED DELAYED FLUORESCENCE; a glowing emitter that manages itself in a restrained, almost circumspect, way.
There are also some acronyms that indicate how the item is fabricated. ALD, for example, refers to ATOMIC LAYER DEPOSITION, that relates to the way that the encapsulation is engaging its' protective enveloping layering.
All of these facet\fun fact acronyms also get considered in the engineering and OLED product pre-planning stages. What will the OLEDs performance actually be like? This is dictated by color measurement parameters, and metrics like these come up: An OLED light engines chromatic output details are important to a lot of us. Some acronyms I bet you know & use in your part of the lighting ecosystem. CRI stands for COLOR RENDERING INDEX and I'm sure you already know that CCT stands for COLOR CORRELATED TEMPERATURE. Oh, and there no way I can leave out that OLED tech has an abundance of acronyms! I haven't touched on the wares constructs fully...If you have ever seen one of those cutaway diagrams of an OLED then you could guess there are a few more. A visual will do this part effectively as a stand in teaching aid and I'll enumerate a few more then finish up.
YOU CAN ADD THESE ACRONYMS AS WELL: ETL, HTL, EML, HBL, EIL & let's not forget everyones' little favorite, the hole injection layer, HIL.
Did I neglect a dozen or more? Probably ... more things become known with a little scrutiny. Here is the pay off for you. IF you were to memorize all of the OLED centric acronyms and IF the topic of OLED ACRONYMS came up on Jeopardy episode on TV - YOU WOULD ACE THE CATEGORY! An OLED Acronym Champ. Such wisdom and mental adroitness will differentiate you from 99.999% of the crowd ...you SSL scholar, you!
- don't expect any benefits, actual pay or real life adulation -