Apple Using LG for 2.13-inch Microdisplays on 2024 Apple Watches

According to Omdia’s David Hsieh, to mark it’s 10-year anniversary, Apple is to launch the Apple Watch Ultra 2 series – an Apple Watch with Micro LED displays offering the following features: 2.13-inch, 325 PPI, RGB Micro LED, flip chip, 80µm pixel pitch, over 900,000 Micro LED chips, stacked hybrid Micro LED pixel architecture, LTPO backplane, and electrostatic transfer process.

Apple first launched its iconic Apple Watch in 2014 and over the last ten years, has become one of the most popular wearables.  Apple is now looking to expand by penetrating the most high-end sports and professional outdoor watch markets. Against this backdrop, Apple has been working on the Apple Watch Ultra 2, a premium model which will be equipped with super high brightness and high contrast ratios, as well as Micro LED displays with tough robustness, water and dust resistance, and strong shock-proof and vibration-proof capabilities.

Micro LED displays are recognized for their performance, including their longer lifetime, lower power consumption, better visibility under sunlight, and tougher robustness than current flexible OLEDs, which have been applied in the Apple Watch series since 2014. 

However, the high-resolution Micro LED displays will cost significantly more than flexible OLED displays owing to the multiplex of RGB Micro LED chips, the difficulty of the mass transfer, and the complicated modulization of Micro LED display units.

Since its debut in 2014, Apple Watch displays have gone through several changes:

  • In 2014, the Apple Watch started with Series 1, which had a 1.34/1.53-inch LTPS OLED panel and 326 PPI pixel density. Apple Watch always has twin display sizes in each series: a smaller size for the Asian market and a bigger screen for the international market. This twin-size principle has applied to every Apple Watch series from 2014 to 2024; the display supplier is LG Display, and the OLED brightness is 1,000 nits.
  • The Apple Watch Series 4 was equipped with a 1.57/1.78-inch LTPO OLED panel. The screen sizes were upgraded (referred to as a “size up” by the display community), but the pixel density remained at 325 PPI. LTPO backplane was introduced, with lower power consumption. Samsung Display retreated from supplying flexible OLED, but JDI joined in 2019 as a new LTPO backplane OLED supplier.
  • The Apple Watch Series 7 and 8, in 2021 and 2022, again saw screen sizes upgraded to 1.71-inch and 1.92-inch sizes, respectively; pixel density remained the same.
  • In 2020, the Apple Watch was extended to an economic model that was more affordable—the Apple Watch SE series. Its screens were smaller (1.34/1.53 inches) and had an LTPS backplane; this meant the power consumption performance was comparatively weaker, but costs could be reduced because the LTPS backplane required fewer manufacturing processes than LTPO. 
  • In 2022, the Apple Watch SE series was extended to the SE 2 series, with bigger screens (1.57/1.78 inches) and a new OLED supplier, JDI. The backplane was changed to LTPO for lower power consumption and because JDI is increasingly mature in its LTPO backplane production (which helps to facilitate lower costs). 
  • For high-end sports, professional athlete-like, and outdoor markets, the Apple Watch Ultra series was launched in 2022. It was equipped with a bigger screen (1.99 inches) to facilitate visibility and readability in outdoor environments; ambient light will be especially strong on sunny days or at noon. The PPI remained the same (325 PPI), and panel supplier LG Display adopted a new version of the LTPO backplane for lower power consumption. Another critical feature of the Ultra series is it is waterproof.
  • In 2024, the Series 8 and 9 (1.71/1.92 inches) will evolve to Series X (X meaning tenth) with a bigger screen (1.89/2.04 inches). The displays will have the same supplier, LG Display, and take LTPO backplanes. Apple might announce the product in late 2023 to commercialize it in 2024.
  • In 2024, the Apple Watch SE 2 series will evolve into the SE 3. Its screen sizes will be the same as Series 8 and 9 (1.71/1.92 inches), and the LTPO OLED panel supplier will be JDI. Apple might announce the product in late 2023 to commercialize it in 2024.
  • The biggest evolution will be the Apple Watch Ultra 2 in 2024, which will adopt a new Micro LED display. Apple might announce the product in late 2023 to commercialize in 2024. The panel size is 2.13 inches with 325 PPI; therefore, the resolution will presumably be 540×440 or 556×452, which means there will be over 800,000 Micro LED chips aligning with the subpixels, including redundant LED chips. State-of-the-art technology will be used to produce this superior Micro LED display.
  • Apple has been developing its Micro LED displays for a long time and is working with LG Display on a new 2.13-inch screen for mass production. Apple will be in charge of the technology and equipment, while LG Display will oversee mass production and testing. The Apple Watch Ultra 2 is intended for outdoor and professional watch applications. Therefore, it will be the most high-end segment of all Apple Watch series, with the highest price position and cost structure. In other words, it might be the ultimate apex of smartwatch displays.
  • It makes sense for Apple to apply a better display (the Micro LED) for power-saving and to address outdoor (stronger ambient lights) concerns with its Ultra series. This is especially so that the series can capture more market share in the professional smartwatch segment (over $800– 1,200) currently led by Garmin. Garmin is adopting a memory-in-pixel (MIP) transflective LCD for outdoor and long-lifetime smartwatch displays. 

Apple’s Micro LED display development status

Apple has a long history of realizing Micro LED displays for mobile applications and AR/VR near-eye displays. On the other hand, Apple invested in LuxVue in 2014; the company has developed many technologies and patents in electrostatic mass transfer.

The following shows Apple’s Micro LED display development path.

  • In February 2019, Apple was approved to build a new Micro LED and R&D fab in Taiwan’s Hsinchu Science Park. At the fab, R&D activities were to be conducted to improve Apple’s Micro LED technology, which it had developed since 2014. Given the current status of this plan, Apple will launch its own Micro LED display product after 2023. Omdia estimates Apple had started building its R&D fab in 2020 and ran it in 2021 to develop actual products in 2022; the products are set to launch in 2023–24 as a best-case scenario. The Taiwan site will be in charge of the pilot-run production, while mass production will involve collaboration with LG Display in South Korea.
  • Apple has targeted Micro LED smartwatch displays, which should be more readable in outdoor conditions, and is expanding the technology to AR devices and smartphones in the future. It will be easier to develop Micro LED smartwatch displays because they are smaller than 2.5 inches with a resolution of 300–400 PPI. Developing Micro LED displays for AR devices and smartphones is more difficult because these applications require a higher resolution. In addition, smartphone displays are definitely larger than 2.5 inches, meaning more Micro LED subpixel chips are needed.
  • Apple concluded that Micro LED displays could have a simpler structure than LCDs and a longer lifetime than OLED displays. Apple has developed not only Micro LED displays but also Micro LED chips. The Apple Watch may be the first proper product for Micro LED displays because the watch display is smaller than other display devices. Apple had first applied flexible OLED and LTPO technology on its Apple Watch before adopting it for the iPhone.
  • Apple planned to achieve the current control circuit by 2022 and merge the sensors on pixels by 2023. Apple has hit a few technical hurdles (uniformity of the Micro LEDs and compensation circuit) and has postponed mass production several times but is getting closer to mass production. Apple is co-developing Micro LED displays with EPISTAR and ams OSRAM (epi wafer/chip), LuxVue (singulation and transfer), LG Display (LTPO TFT backplane), TSMC (transfer and CMOS backplane), and ITRI (micro-assembly).
  • Apple acquired LuxVue in 2014 for its Micro LED manufacturing patents; the company was established in 2009. Based on technology from ITRI in Taiwan, LuxVue has a series of patents on the singulation and mass transfer of Micro LED chips. LuxVue’s mass transfer concept is based on electrostatic microelectromechanical sensor (MEMS) technology, which can control each pick-up head individually. It is believed that the electrostatic power can degrade the P-N junction of the Micro LED permanently or damage the contact electrode. LuxVue has also suggested a manufacturing process for vertical LED chips and a method for their mass transfer. However, Apple has applied flip LED chips and a carrier substrate, an easier process than LuxVue has proposed.
  • Based on its long-term technology roadmap, Apple seems focused on improving the integration of circuits for the main system and the display. Apple has asked a few display suppliers to develop OLED displays based on LTPO TFT. Their efforts are targeted at lowering power consumption and fabricating additional sensors with the oxide TFT. For OLED, the luminance efficiency can be increased to a limited amount compared to LED or Micro LED displays, so it is reasonable that Apple would develop Micro LED displays.

Apple’s Micro LED display supply chain

We estimate that the Apple Watch Micro LED displays will have the following features: 

  • 2.13 inches
  • 540×440 resolution, which means the Micro LED chips will be 540×440 x 3 (RGB subpixels) x 1.2 (for redundancy RGB chips) = 0.9 million units
  • Micro LED chip size of 10µm; Micro LED display pixel pitch of 80µm
  • Micro LED chip style of flip chip and photo-detecting LED
  • Stacked hybrid Micro LED pixel and subpixel structure, as shown in Figure 2 
  • LTPO TFT backplane
  • Electrostatic mass transfer (from LED epitaxy wafer to the LTPO backplane) 

The following are our estimations regarding the Apple Watch Micro LED supply chain:

  • The main Micro LED equipment (such as transfer and critical optical testing and repairing machines) will be authored by Apple.
  • LTPO TFT backplane will have a glass base made by LG Display, which will allocate the backplane capacity from its AP3-E5 Gen6 TFT and flexible OLED fab. About 5,000–10,000 units of Gen 6 substrates per month of capacity can be arranged for Micro LED display production. Each Gen 6 substrate can be panelized with over 1,000 pieces of 2.x-inch displays.
  • Ams OSRAM as the supplier of Micro LED epitaxy wafer for chips. 
  • LuxVue and Apple’s Taiwan R&D center are in charge of the Micro LED chip singulation and electrostatic mass transfer.
  • Apple is also working on another version of Micro LED displays, based on mass transfer and CMOS wafers; this involves collaboration with TSMC.
  • ITRI in Taiwan works on the micro-assembly.
  • The final Micro LED display module assembly will be by LG Display in South Korea.
  • The final Apple Watch assembly will be at Foxconn and Luxshare’s Vietnam factory. 

Apple’s Micro LED display cost

With the number of Micro LED chips used (over 0.9 million units of LED chips) and the LTPO backplane’s complicated process, Micro LED display costs will certainly be higher than the current flexible OLED. However, the merit of Micro LED displays for the Apple Watch will be high brightness, outdoor readability, robustness for professional outdoor usage, and the super-slim display form factor to facilitate a larger space for the battery.

Omdia estimates the Apple Watch’s Micro LED 2.13/2.2-inch screen with 556×452 resolution will be manufactured at $115 in 2024. The touch and cover lens will be added, costing an additional $10. Compared with the average price of a 2.0-inch flexible OLED, which is $38–40, Micro LED display costs will triple. The key cost elements are not just the Micro LED chips but also the LTPO backplane, the mass transfer, the modulation, the driver IC, the testing and repair, and the final assembly.

The high cost of Micro LED displays will push the Apple Watch Ultra series to a price position exceeding $1,200—like the Apple Watch Hermès, currently.

Apple Watch Hermès, in the luxury segment, is tagged at $1,759, compared to the $399 price tag of the Apple Watch 8 series.

Apple Watch display volume forecast

Apple has been purchasing flexible OLED for 40–50 million units per year. The Apple Watch continues to be popular in the end market; therefore, flexible OLED smartwatch display shipments continue to rise. Each series presents different volumes; the current situation is as below:

  • Apple Watch SE series (1.6-inch and 1.8-inch): 18 million to 20 million units per year. Apple plans to defocus this segment gradually but to move to larger sizes
  • Apple Watch 7 series (1.7-inch and 1.9-inch): 25 million to 26 million units per year. Apple plans to expand this segment to over 50 million units per year, including the larger-sized SE series
  • Apple Watch Ultra series (2.0-inch): 3 million to 4 million units per year now. Apple plans to expand this segment with the new Micro LED display and the larger-sized Series X.

In other words, Omdia expects Apple Watch Micro LED display units to amount to 3–4 million per year in the initial years (2024–25) and grow to 10 million units per year in the long term (2028–29). Accordingly, Apple is equipping three Micro LED display module production lines; the first will be ready in 2023. The production lines are segmented according to processes for Micro LED and displays. This is one of the reasons why the lines are installed at LG Display’s facilities, while Apple will take charge of the Micro LED process by itself.