Smartphones
Evolution of the Galaxy Z Fold Series: Thinner, Sturdier and Compact as Ever
6/26/2024
A foldable is exactly that — a folding phone. Unlike bar-type smartphones with a single body, foldables consist of a central hinge and two folding sides. The hinge serves as the central axis for opening and closing the phone. Over time, Samsung has introduced unique, cutting-edge technology into the hinge mechanism of its Galaxy Z Fold series to create a revolutionary hinge design with each release. In addition, Samsung has continued to reduce the thickness of the Galaxy Z Fold series so the phone can be carried anytime, anywhere.
Samsung Newsroom looked back at the evolution of the Galaxy Z Fold series’ sleek profile and distinctive hinge design — now thinner, sturdier and compact as ever.
[2019] Galaxy Fold
The Dawn of Foldable Phones: Folding and Unfolding
Thickness when folded: 15.7-17.1mm Thickness when unfolded: 6.9-7.6mm Weight: 276g
As user lifestyles continue to diversify, so too do their needs. Samsung has consistently introduced advanced technologies each year to meet these changes. First unveiled in 2019, the Galaxy Fold featured a groundbreaking form factor — the first to deliver a natural, big-screen experience when unfolded and a compact, portable experience when folded. The act of “folding and unfolding” emerged as a new category of mobile interaction, and Samsung applied never-before-seen hinge technology to ensure this functionality felt natural and intuitive.
The inward-folding hinge not only felt familiar and easy to use, but it also provided robust display protection. The phone could be smoothly opened like a book, yet stay flat and thin when folded. The palm-sized dimensions were key to its convenience. With the first Galaxy Fold, Samsung achieved a maximum folded thickness of just 17.1 millimeters and ushered in the era of smart foldables.
[2020] Galaxy Z Fold2
The Era of FlexMode: Hideaway Hinge and Sweeper Technology
Thickness when folded: 13.8-16.8mm Thickness when unfolded: 6.0-6.9mm Weight: 282g
In 2020, the successor to the pioneering Galaxy Fold was released. The Galaxy Z Fold2 took foldables to the next level with an all-new sophisticated and refined design. The most notable of its several innovative features was the Hideaway Hinge, which seamlessly connected the body of the smartphone while supporting stable folding and unfolding. Users could mount the Galaxy Z Fold2 at various angles with the Hideaway Hinge to easily take selfies and make video calls in FlexMode.
The Hideaway Hinge’s more than sixty parts made the innovative dual CAM mechanism a reality. The flat surface between two ridge-shaped parts, CAM helped keep the device open or closed and enabled FlexMode. By increasing the number of CAM structures and springs, the hinge could reliably support wider angles. The Hideaway Hinge was mounted on an optimal location on the Galaxy Z Fold2 for an even slimmer design and a maximum folded thickness of just 16.8 millimeters.
Since the hinge was constantly folded when the device was opened or closed, there was an inevitable gap between the front of the device and the hinge housing. To effectively minimize this gap, Samsung needed to develop a component that would be long-lasting and elastic without adding extra bulk. Inspired by the brush of a vacuum cleaner, Samsung made use of delicately cut optical fibers to address this issue: Sweeper Technology. Sweeper Technology protected the phone’s display from external dust and debris that could enter through the gap, providing a more fluid foldable device experience.
[2021] Galaxy Z Fold3
The Solution to the Foldable Phone’s Biggest Challenge: Waterproofing
Thickness when folded: 14.4-16.0mm Thickness when unfolded: 6.4mm Weight: 271g
It’s a given that today’s smartphones are waterproof. However, the hinge that opened and closed the screen on foldables would always be exposed to the elements. If liquids such as beverages or even rainwater leaked inside, the device would be at risk of immediate malfunction.
The Galaxy Z Fold3 was the first foldable to be water resistant, one of the biggest challenges that previous foldable devices faced. Samsung’s waterproofing technology was applied to two areas — the outer part of the display and the hinge. The outer part of the display was surrounded by a rubber band that prevented dust and liquid from entering, whereas the metal parts of the hinge were made of corrosion-resistant materials and coated with a long-lasting lubricant. The terminal connecting the two mainboards bordering the hinge was sealed with a silicone-based cured-in-place gasket (CIPG) that prevented liquid from entering the device. Additionally, flexible printed circuit board (FPCB) cables were used to protect sensitive components.
A robust material that withstands external shocks and reduces the risk of deformities or scratches, Armor Aluminum was used to help the Galaxy Z Fold3 achieve an even thinner and lighter form factor.
Armor Aluminum was applied to the two edges that make up the exterior and to the housing that surrounds the hinge. Various components were densely packed inside the Galaxy Z Fold3’s Hideaway Hinge to enable FlexMode and ensure smooth opening and closing. To support these functions, the hinge housing needed to be made from sturdy materials.
The Sweeper Technology that closed the gap between the hinge and the body of the foldable evolved too. As the device became slimmer, the sweeper’s bristles were shortened to improve aesthetics while still keeping the hinge safe from dust and external particles. These innovations allowed the Galaxy Z Fold3 to be as thin as 16.0 millimeters when folded.