Oura's Ring 5 is a dramatically thinner smart ring - Engadget

Oura Ring 5 is designed to be less bulky by shrinking 40% compared with the previous model. The ring’s components were redesigned to reduce size while improving power efficiency. Signal pathways were reduced from 18 to 12, with changes to the sensing and lighting system. Ring 4 used four low-power photodetectors with low-power LEDs, while Ring 5 uses LEDs that are four times as powerful paired with three photodetectors for more accurate readings across a wider range of skin tones. Ring 5 is offered in sizes 6 through 13, while Ring 4 remains available for smaller and larger sizes. New finishes include Stealth, Brushed Silver, a more natural Gold, and Deep Rose, with improved scratch resistance via a new vapor deposition method.

"Oura is looking to solve with the new Ring 5, which is a whopping 40 percent smaller than its immediate predecessor. Shrinking such a small piece of gear down by that much has taken a lot of engineering, but the company says it comes with no compromises. If you've previously been put off by the bulk of most smart rings, then today might have all the makings of your lucky day."

"To reduce the size by almost half, every part of the ring has been redesigned to be both smaller and more power-efficient. Those with a keen eye on the spec list may notice the number of signal pathways has dropped from 18 on the Ring 4 to 12 on the Ring 5. Russell explained that the 4th-gen ring had four low-power photodetectors, which worked in tandem with low-power LEDs."

"The Ring 5's LEDs are four times as powerful, paired with three beefier photodetectors which, Oura says, offers better, more accurate readings across a wider range of skin tones. The company is also responding to relatively lukewarm demand for the smallest and biggest ring sizes."

"Whereas the Ring 4 comes in sizes 4 through 15, the Ring 5 serves sizes 6 through 13. Oura doesn't think it's boxing out would-be buyers but Russell added that the Ring 4 will remain on sale to help cater to those groups. Naturally, Oura is also leaning harder into the fashion angle and is talking up the new paint jobs on these rings."

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