Galaxy Z Fold 2 has the smallest curvature, Samsung Display says 

Samsung Display said on Wednesday that the OLED panel of the Galaxy Z Fold 2 had the word’s smallest radius of curvature at 1.4R.

1.4R means the curvature of the display when folded equals that of a circle with a radius of 1.4mm. The smaller the number, the more the display can be folded.

Samsung said the OLED panel on the Fold 2 has the smallest curvature radius of commercial displays.

The Galaxy Fold launched last year and Galaxy Z Flip launched earlier this year had panels with a 1.5R curvature. Galaxy Fold used a polyimide film as the cover while the Flip and Fold 2 uses ultrathin glass.

Fold 2’s folded length increased by 1.7 times compared to the Flip which made applying ultrathin glass more difficult but the company achieved this, Samsung Display said.

The Galaxy Z Fold 2 survived over 200,000 folding tests. The panel is made out of multiple layers that must survive both pressure and tensile stresses. This folding stress increases as the curvature becomes smaller. 

Samsung Display optimized the materials, design and module technology to achieve this feat, it said.

In-folding, in which the panels are folded inwardly, is considered more difficult to achieve than out-folding as the required curvature becomes smaller.

The 1.4R foldable OLED has been verified for durability by BureauVeritas. The display also got an Eye Care Display certificate by SGS2 for 6.5% blue light.