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High degree of significance for the elimination of QD's in microled. This I think would have been a factor in putting the company up for sale, as it closes off an additional revenue stream that had the potential to be lucrative.
Yes I agree, just went though the video again, and does look it red no longer needs nano dots.
Morbox, I posted the exact same link 8 July on 'Plessey @ SID 19' thread together with JB Display video at same event. www.youtube.com/watch?v=52ogQS6QKxc
They are using monolithic technology (like Plessey) and have 'No phospher, no pick&place, no mass transfer, no quantum dots needed.
I think the ability to create native Blue, Green and now Red (like JBD) eliminates the need for colour conversion and removes limitations in QD's smaller than 5µm?
Plessey Guy talking about wafers. Great video on MicroLeds. You need to watch it I can’t remember when Nano dots are mentioned but it is.
https://youtu.be/4PqMQobkUhg
I think the process still requires Nano dots, could be wrong, sometime ago I posted a video link about this subject and a Plessey guy run through the making of the wafers. I’ll try and find the post later.
https://optics.org/news/10/12/11
Plessey develops native Red InGaN LEDs on silicon
06 Dec 2019
New approach to microLED is attractive because it offers lower manufacturing costs and scalability to larger wafers.
Plessey, an embedded technologies developer of microLED technologies intended for augmented reality and display markets, has developed what it calls The "world’s first GaN (gallium nitride) on silicon-based Red LED.
InGaN-based blue and green LEDs have been commercially available for some time, but red LEDs are typically based on AlInGaP material or color-converted Red. For AR applications, Plessey comments that achieving high efficiency ultra-fine pitch Red pixels (< 5 µm across) remains elusive due to severe edge effects from AlInGaP material and cavity losses from colour conversion processes.
InGaN-based Red is attractive because it offers lower manufacturing costs, scalability to larger 200 mm or 300 mm wafers and better hot/cold factor over incumbent AlInGaP-based Red.
However, achieving red spectral emission with InGaN material is challenging due to the high indium content, inducing significant strain in the active region, subsequently reducing crystal quality and creating numerous defects.
Strain-engineered active region
Plessey says it has successfully overcome these challenges by using a proprietary strain engineered active region to create an efficient InGaN Red LED. The new InGaN Red microLEDs offer an output wavelength of 630 nm at 10 A/cm2, full width at half maximum of 50 nm, hot cold factor over 90% and higher efficiencies over conventional AlInGaP and colour converted Red at ultra-fine pixel pitches.
With these specifications, Plessey says it now has the capability to manufacture native Blue, Green and Red InGaN material or tune wavelengths from 400nm – 650nm using its GaN-on silicon platform.
Dr Wei Sin Tan, Director of Epitaxy and Advanced Product Development, at Plessey, commented, “This is an exciting result as it creates a path towards low cost manufacturing of ultra-fine pitch and efficient Red InGaN pixels, which will accelerate the adoption of microLEDs in both AR microdisplays and mobile/large display applications.”
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Correct me if I'm wrong but reading this it would seem Plessey no longer have need for QD's in their Microled displays?
Similar to native Blue and Green Microled - they can now create native Red without any colour conversion needed? (see my last post on this thread).
Mystery of why issue with < 5 µm mentioned before by Dr Wei Sin Tan was due to 'severe edge effects from AlInGaP material and cavity losses from colour conversion processes'.
Great research and comments, as ever on this board. My thanks to all contributors.
Despite the promise shown by the potential applications for Nanoco's products, there has been a dearth of information from the company since the CEO's affirmation of its 'strong operational performance' on August 15. His positive statement, which amounted to a reiteration of previous information already known by the market, had zero effect on the share price. Subsequently, the share price has mostly remained in a steady trading range with occasional up and down fluctuations.
I am not holding my breath regarding the final results originally scheduled for publication tomorrow, but with the publication date now apparently put back by a day. Some positive news would be most welcome, although I am anticipating a longer time frame before this investment comes to fruition.
The further pixel shrinkage was only announced in September AFAIK, so a more recent improvement.
Thanks for providing link Eccles although still not sure about Plessey.
Been trying to research further -
Here's a link I found dated 5 Apr 19 detailing Plessey's native green micro-LEDs -
https://www.electronicsweekly.com/news/business/manufacturing/plesseys-pins-future-micro-led-displays-gears-production-2019-04/
Excerpt:
'Plessey’s big announcement this week is the development of native green-emitting micro-LEDs – as opposed to the less efficient combination of blue-emitting quantum wells and a blue-to-green quantum dot phosphor.
On the firm’s roadmap is a single micro-display combining native blue and green quantum wells with a phosphor converted red, but before then it is working towards a colour micro-display using three separate die for red, green and blue.
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I guess this means they are using (or plan to use) Quantum Dot phosphor for the red only?
Then their direct drive platform states pixel capabilities down to 2-micron - http://www.plesseysemiconductors.com/plessey-launches-microled-direct-drive-display-platform/
Strange if issue with QDs below 5-micron (9 July 19)? Maybe limitation in product format/design (layer thickness) for single RGB? (don't know)?
Also Plessey state (3 Jan 19) down to 4 micron with QDs - http://www.plesseysemiconductors.com/nanoco-plessey-partner-shrink-full-colour-microled-pixels-87-using-quantum-dots/
'Using its existing monolithic process, Plessey will integrate the Nanoco CFQD® quantum dots into selected regions of blue LED wafers to add red and green light. This shrinks the smallest practical pixel size from today’s 30µm to just 4µm, a reduction of 87%.'
#Confused.com
My inkling is leaning more towards JB display based in China. Changying Precision are Chinese company (chassis supplier). JBD YouTube video mentions cheaper than LCos, DLp, Oleds. Also Plessey are working with Vizux AR glasses - I just don't see Apple using same tech as Vizux but happy to be proven wrong. Will keep looking.
Upbeat, I'm just speculating that Apple canceled the project with Nanoco because they could not overcome the motion-to-photon latency and power requirement for AR or that they accepted another company had overcome this issue and possibly had IP protection. I'm guessing Plessey as the were also working with Nanoco.
Apple could have had this senario in mind from the outset, build a facility to make the QD if we can't use it a supplier will.
https://www.engineering.com/ARVR/ArticleID/19375/Apples-Reportedly-Throws-in-the-Towel-on-AR-Glasses.aspx
I'm not sure what you are referring to Ecclescake. As far as I am aware the reason for the cancelled QD camera with Apple was due to cost for mass production thus they are going forward with rumoured TOF camera (my last post).
https://www.patentlyapple.com/patently-apple/2019/07/rumor-claims-two-taiwanese-micro-led-suppliers-will-make-displays-for-apple-watch-as-soon-as-2020.html
I think it's still up-in-the-air as to who the 3rd parties may be (see link above). Someone on the board also mentioned Playnitride (not sure). Maybe makes sense of different suppliers req. for different product eg watch v VR/AR device? Here's both youtube videos featuring Plessey and JBD @ SID this year. www.youtube.com/watch?v=4PqMQobkUhg www.youtube.com/watch?v=52ogQS6QKxc
I'm not ruling Plessey out either but I still can't get past Dr. WeiSin Tan statement from the Microled forum 2019 regarding current QD material limitations if Micro LED pixels are smaller than 5µm - https://www.ledinside.com/news/2019/7/microledforum_2019_highlights_2
If 2-4µm pixel may be required for VR/AR devices?
https://www.linkedin.com/pulse/big-step-micoleds-brings-smartglasses-closer-ben-delaney
Hawi I think you have hit the nail on the head. I read an article a while back that reported the reason for the project with Nanoco was canceled is because Apple could not reconcile the power consumption required to run AR specs. Now it looks like they have decided to go through 3rd party supply, possibly with Plessey. It would explain why they were happy to see the production capability at Nanoco Runcorn, Plessey will use our CFQDs.
https://youtu.be/5aivhq9nxOs?t=94
I think this may be the TOF camera/sensor Apple will use by STMicroelectronics (or something similar?). Same company who were supposed to create QD sensor but Apple cancelled due to too high expense in mass production. No mention of QD tech though but much cheaper presumably and rumoured direction Apple taking atm also mentioned here. https://www.macrumors.com/2019/07/29/kuo-2020-iphones-3d-sensing-rear-cameras/
Unlikely to have any impact on us, but may contain QD tech, so worth keeping an eye IMO. https://www.macrumors.com/2019/10/09/kuo-ipad-pro-3d-camera-scissor-macs-q2-2020/