Answer: Smartwatch heart rate sensor
by MalachiteRun · 10 guesses · hard
What you're looking at
A smartwatch heart rate sensor is the small circular component on the underside of your wrist-worn fitness tracker or smartwatch. It's designed to make direct contact with your skin and monitor your cardiovascular activity throughout the day, providing real-time data about your physical exertion and overall health.
When magnified dramatically, this photo reveals the intricate grid of tiny LED emitters and photodiodes that make up the optical sensing technology. The pattern looks almost like a metallic circuit board covered in small bumps and ridges, making it nearly impossible to recognize as part of a wearable device until you know what you're looking at.
Search for repeating geometric patterns of tiny raised components or sensor grids in extreme close-ups of electronic devices.
How players did
2 players made 10 guesses. It took 9 guesses before someone got it right.
