The Key Ingredient Behind iPhone Ultra’s Creaseless Foldable Display: Innovative Glue Technology

The forthcoming Apple iPhone Ultra is generating significant buzz as one of the most awaited consumer technology releases of 2023. The excitement surrounding its innovative creaseless display is palpable, especially in light of the less than stellar real-world performance of competitors like the Oppo Find N6, which has faced issues with creasing in its foldable display over time. Details from recent observations highlight this growing concern.

According to a recent report by TrendForce, Apple’s aspirations for a truly creaseless foldable display hinge on a specially formulated adhesive.

Innovative Technology Behind the iPhone Ultra’s Creaseless Display

TrendForce predicts that the iPhone Ultra could capture 20% of the global foldable smartphone market by 2026. However, some technical challenges remain unresolved. The formation of creases in foldable displays is attributed to minute misalignments within the neutral layers, which worsen over time, leading to stress concentrations that can cause micro-cracks and permanent deformities.

Apple’s approach, as outlined in various patents, provides a fresh perspective on mitigating this issue. Notably, the Ultra-Thin Glass (UTG) incorporated into the iPhone Ultra’s foldable display is expected to feature varying thicknesses, with the folding segment being notably thinner than the rest of the screen.

Additionally, Apple appears to be leveraging a unique type of glue: Optically Clear Adhesive (OCA).Distinguished by its viscoelastic properties, OCA remains pliable during gradual bending, reducing strain, and hardens instantaneously under direct force, while its micro-fill characteristics address microscopic cracks, thereby minimizing the risk of display creasing.

The Crucial Role of the Hinge Mechanism

In a related report from South Korea, it has been revealed that Apple is collaborating with Samsung Display to produce 8 to 9 million foldable display panels intended for the iPhone Ultra by the conclusion of 2026, suggesting a planned sale of 7 to 8 million units annually.

The hinge mechanism, a vital aspect of the phone’s design, is being developed by US-based Amphenol. However, challenges persist in achieving stability, raising concerns about potential launch delays. Additionally, Apple is sourcing UTG cover from manufacturers in China and South Korea.

Current Insights on Features and Specifications

It is understood that the iPhone Ultra will sport a complex hinge mechanism. Reports suggest that Apple may implement a dual-layer design of UTG and Ultra-Thin Flexible Glass (UFG) to shield the display layer from mechanical wear while evenly distributing stress throughout the fold, thereby effectively minimizing creasing. As per Taiwan’s Economic Daily, the anticipated crease depth for the iPhone Ultra measures an insignificant 0.15mm.

Moreover, Apple plans to introduce a color filter, known as the CoE (Color Filter on Encapsulation), on the protective encapsulation layer of the iPhone Ultra’s OLED display. This novel approach favors thinner, lighter, and more energy-efficient screens. The CoE filter replaces the traditional thick circular polarizer with a thinner, directly applied color filter layer. In combination with a black pixel definition layer (PDL), this method achieves higher light transmittance and decreased power usage. This thinner profile ultimately lessens stress on the device, enhancing durability and allowing for a tighter folding radius.

Additionally, speculative pricing suggests that the base price for the iPhone Ultra may hover around $2, 000, which is a considerable reduction from earlier estimates of $2, 300 to $2, 400. Bloomberg’s Mark Gurman also disclosed that the iOS interface for the foldable variant will feature “iPad-like layouts”to facilitate multitasking, with simpler multitasking capabilities compared to the more complex desktop-like UI seen in iPadOS 26. The internal display is projected to be iPad-sized with a wider aspect ratio, while the external screen will mirror that of a smaller iPhone.

Gurman indicates that the foldable iPhone’s exterior display will incorporate a small hole-punch cutout, complemented by the Dynamic Island UI for notifications. Notably, Apple has opted to phase out Face ID, opting instead to integrate Touch ID within the side button. While Apple is trialing an under-display camera for the internal display, early results have resulted in subpar image quality, diminishing the likelihood of this feature being included in the final product. The phone is anticipated to feature a dual rear camera setup, with both cameras boasting a 48MP resolution.

Other expected features include: