Expect To See A Lot Of Mini And Micro LED At ISE 2020

Integrated Systems Europe starts three weeks today in Amsterdam, and the PR is starting to roll in from display and software vendors, trumpeting what will be shown at stands at the big AV/IT trade show.

A main thing I will be looking for that week is the expected advances in LED display tech, coming mainly out of China and Taiwan (but also Korea).

China’s Absen, to name one vendor, has already sent along press material noting it will have a CR series display that has a 0.7mm pixel pitch, the company‚Äôs smallest pixel pitch and highest resolution display. There is also a new 0.9mm MiniLED display aimed at the high-end control room market.

As I have noted in the past, the terms miniLED and microLED are, being polite about it, broadly interpreted and presented by vendors. Absen says it will also show rental displays that are 1.2mm to 1.9mm miniLEDs, and I really don’t think that relatively coarse pitch would be defined as mini. Guess I will see once at the show.

The Taiwan tech publication Digitimes has a round-up on its site about what it saw at CES with mini and micro LED, and given that almost all of those manufacturers also have stands at ISE, and that big-dollar displays have more prospects of being sold for commercial purposes, much of that tech should be at the RAI Amsterdam.

Sony, Samsung Electronics and LG Electronics had showcased large-size micro LED TVs while China-based TCL, Konka and Leyard Optoelectronic had exhibited large-size RGB (red-, green-, blue-light) fine-pitch mini LED displays at CES 2020 during January 7-10, signaling that micro LED TVs will have a good chance to come into production in the second quarter of 2020 and demand for large-size RGB fine-pitch mini LED displays is growing in the year.

Sony had showcased a 220-inch 4K Crystal LED display system, an equivalent to a micro LED TV. Samsung had exhibited 88-, 93-, 110- and 150-inch The Wall series 4K modular all-screen micro LED TV models as well as a 292-inch 8K mini LED TV.

LG showcased a 145-inch Real Micro LED Display consisting of 48 micro LED display modules in mosaic with micro LED chips of below 50 microns in diameter.

LG’s “Real Micro LED” moniker may be an intentional marketing slap at rivals who call their mini displays micro, whereas what it has – “micro LED chips of below 50 microns in diameter” – easily meets the generally accepted technical threshold of microLED.

Konka had showcased 118- to 236-inch Smart Wall series modular micro LED TVs. TCL had exhibited a 132-inch The Cinema Wall 4K micro LED TV; Leyard had showcased a 216-inch The Great Space 8K micro LED TV. However, these so-called micro LED TVs are similar to large-size RGB mini LED displays with ultra-fine pitches.

While micro LED refers to LED chips of below 100 microns in diameter and mini LED to those of above 100 microns, the two differ additionally in manufacturing process. Micro LED chips have to be removed from sapphire substrates onto temporary substrates first and then transferred onto back planes using a mass transfer process, with mass transfer processes faced with technological challenges of how to accurately array so small micro LED chips on back planes.

In comparison, mini LED chips need not be removed from sapphire substrates, with manufacturing process similar to that for LED chips.

An aside: That nerdy description about mass transfer is important if you are trying to learn this stuff. A key reason microLED is Russian oligarch-expensive is the amount of manufacturing time and equipment needed to make a single display module, never mind a whole wall of them, and the challenge of minimizing flaws. When you are creating an array of millions of light chips, even a percentage of flawed LED dies of .0001% could mean 100s or 1,000s of dead pixels.

Of all these vendors noted by Digitimes, TCL is the only vendor not listed as having an ISE booth, though that doesn’t mean it won’t have gear in someone else’s stand.

The other aspect of miniLED I expect to see quite a bit at ISE is the use of that tech as backlights for high-end LCD displays. LEDs are what illuminate the LCD in a display panel, and by adding more, smaller and controllable LEDs in behind a screen, the display’s output can be more precisely controlled. So for a digital signage message that has one element that is dark, just the LEDs illuminating that local area of the screen are dimmed.