I keep reading messages about mini-LED and Promotion. What is it all about? What is mini-LED? And what is Promotion? Why these features are good things to have on a desktop display? What are their advantages over display that don't have mini-LED and Promotion? Should I really care about mini-LED and Promotion before buying the Studio Display (which doesn't have these features)?
Hi Cham2000,
I'm no expert, but since your query hasn't attracted any experts to answer it, I'll attempt a simple explanation.
Computer monitors are often, at least in the recent past, LCD displays (Liquid Crystal Display). Liquid crystals make up the pixels and are used to block light in varying amounts passing through the pixels from the backplane. The backplane is typically lit by a bank of LED (Light Emitting Diode) lights with the light being funneled to the pixels, often by fiber optics.
[Sometimes, in the past, these LCD displays have been called LED displays, but technically they should be called LCD displays.]
A
regular LCD display uses a bank of LEDs and fiberoptic cables to light the entire backplane of the liquid crystal display with a uniform white light. The liquid crystal pixels then block varying proportions of this light which bleeds through the individual pixels to form the image you view on the display. This type of display typically has a contrast ratio (the ratio for the brightest to the dimmest possible pixel) around a 1000:1 because the entire backplane is uniformly lit with white light and since even for black pixels some of this white light will still bleed through the "black" liquid crystal pixels. These displays also do some other fancy things to allow the viewing angle (the angles to the screen for which you can still view the image) to be expansive. And, of course, there are color filters to provide RGB pixels for color images. In addition, because of the thinness requirements for laptop displays, these displays are usually edge-lit with fiber optic cables employed to conduct the light to the LCD pixels.
[The details of how all this works employs not only liquid crystals but also circular polarizing filters, etc.]
The
mini-LED display, on the other hand, divides the display screen into small regions (sort of like a tiling) with each small region being lit by its own LED(s), and this LED can be switched on or off. Thus the backplane of the liquid crystal display is not uniformly lit, rather each small region is lit separately. This means that a region of the display that is supposed to be black can be truly black since its LED(s) lighting that small region can be switched off and thus there is no light to bleed through the liquid crystal pixels to be seen -- i.e., true black (total lack of light) pixels. This type of display can achieve a contrast ratio of 1000000:1 since the display's blacks are truly black. And, according to Apple, their mini-LED display has 10000 mini-LEDs to light the backplane, but I do not believe there are 10000 different "tiles", rather I think there are more than one mini-LED that lights any particular backplane region. I'm not sure precisely how it is organized, and until the display is taken apart and studied we may not know all of the details.
[An emerging technology called microLED is the extension of the miniLED concept to even more mini-LEDs so that every LCD pixel has its own micro-LED to light it.]
While you didn't ask, I should still probably quickly mention
OLED displays. For these displays the pixels themselves actually emit light (Organic Light Emitting Diode) instead of just blocking light from the backplane. This again means that a black pixel can be truly black since the pixel can be turned off and thus not emit any light. Also OLED displays are often described as having more "vibrant" colors, whatever that means.
Now on to the meaning of
ProMotion:
Until the latest MBPs, the displays typically had a constant refresh rate of 60Hz, 60 times a second the image on the display could be changed. (fps=frames per second) In the old days, movie theaters employed 24Hz films while older TVs used roughly 30Hz (depending on what part of the world you lived in). But with gaming enthusiasts wanting faster refresh rates, displays were designed with faster refresh rates, such as 120Hz, 140Hz, 144Hz, and 240Hz, etc. On a laptop, the refresh rate on the display also affects the battery life since the more often the image is changed the more energy is used to effect those changes. So a laptop with a 120Hz display would use considerably more energy than a laptop with a 60Hz display. So, incomes ProMotion...ProMotion displays can vary their refresh rates automatically to accommodate the actual rate of the video signal, all the way from 24Hz to 120Hz. Thus if you are watching a 24Hz video signal, the display will refresh at 24Hz instead of running at a constant 60Hz, thereby saving a lot of energy and extending the battery life of the laptop. But if you are watching a 120Hz video signal, then the ProMotion display is capable of ramping up its refresh rate to 120Hz to match the video signal. At 120Hz the display is "more fluid", it appears smoother to most people's eyes than if the display is running at 60Hz.
[By the way, the various Hz speeds listed above actually refer to sets of very close speeds, thus 30Hz actually refers to 29.97Hz and 30Hz. There are also 50Hz, 25Hz, 59.94Hz, etc. signals, again depending upon the actual video signal being viewed and in what part of the world.]
The new Apple Studio Display is a 60Hz display. Now having a refresh rate greater than 60Hz is very useful for gaming, but I doubt you are wanting to game on this display, rather you would simply buy a gaming PC with an appropriate 144Hz or 240Hz monitor for your gaming endeavors.
[Supposedly, the professional, expert gamers can tell the difference between 144Hz and 240Hz displays, but I'm sure that my poor, ancient, eyes cannot.]
Hope this simplistic explanation has provided a modicum of help for you.
Regards,
Solouki
P.S. Hopefully an expert will post corrections to any mistakes I've made above and provide you with further details.
