PlayNitride is all microLED at DisplayWeek

PlayNitride was showing microLED implementations on glass, PCB and silicon.

Hi, Chris Chinnock for Insight Media at DisplayWeek 24. I’m in the PlayNitride booth. They develop microLED displays based on three backplanes: PCB, TFT LTPS on glass, and silicon. So, let’s start with their PCB demo they’re showing here this year.

This is a cubed type of display as you can see it’s got microLED displays on all five sides. Here are the details. First of all, this is composed of a number of microLED packages. Each package is 1.1 by 1.1 mm and within that package is a 4×4 array of RGB microLEDs. These are flip chip microLEDs that are in the 15 by 30-micron range. It all packaged as a flip chip device, which can now be used by   SMT type manufacturing processes. This is very compatible with the way digital signage and video wall LED modules are put together today. That’s the whole point of this. Because this is fairly bright, this one is actually 3,000 nits, but they can go actually up to 30,000 nits because it’s passive matrix, which means they can drive it harder. This also means that you have to have a separate driver chip just like you do in normal video wall applications. Second of all, they are going to work on trying to shrink the pixel pitch. The pixel pitch right now is about, well it says it’s 0.33mm for a 76 PPI but they said they’re working to get that down to 0.5 mm, so I’m a little confused on what they were saying. The resolution of each of these displays is 240x 240.

This is their TFT-LCD backplane with microLED demo. This ais a box situation here. You can see the microLEDs in front here – it’s transparent and there’s a little car model in back of that. What’s unique about this configuration, the first time this has been shown, is that they also have bonded, there you go, is a blocking layer. In order to create that transparency, that opaqueness rather for the transparent display they bonded an LCD cell in back of it. This could be a single cell LCD, which it kind of looks like in this case, or it could be multizonal. This allows the transmissivity to vary from 1% to 40%. So, this is fully blocked now and it’s almost like watching an opaque display, which is kind of nice. The 40% on the transmissivity side’s a little low, I think. You want to get higher than that for practical applications. But this that’s an interesting demo to start with. This particular panel is a 9.38-inch transparent microLED display with a resolution of 960x 480 with a 0.22 mm pitch. That’s 114 PPI. Now let’s look at their CMOS.

In this area, PlayNitride is highlighting their manufacturing process. You start with the three different Epi wafers; red, green, and blue. You transfer those onto an intermediate carrier which they call Chip-on-Carrier one and those then get transferred to a second carrier. This Chip-on-Carrier one could be tape or something of the sort and it gets transferred to the COC2 with the final pixel pitch. They can also make this package. This is that small package I was talking about they had in that cube display. And here’s some of wafers that you can see here and they’re also showing over here.

This is an update for their 0.49 in microLED display good for AR applications. They’ve shown this for a couple of years now. With this 0.49 in device, they said they’re getting a 99% yield out of it which is quite good. It’s full HD resolution and it’s quantum dot color converted using photolithography. So last year the brightness was about 150,000 nits. This year they pushed it up to 300,000 nits. The color gamut is good, but again like everyone, they spec this as 100% of NTSC which I find to be a very unattractive way of talking about color gamut. That’s the story here from PlayNitride. Chris Chinnock for Insight Media.

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