Apple is looking not just at maximizing the efficiency of health sensors in the Apple Watch, but also minimizing the space they take up by creating curved sensor elements to fit better in the enclosure.
A new patent application from Apple is chiefly concerned with the specifics of how certain sensors could be deployed within the Apple Watch. However, ultimately it's really about ways to make the Watch thinner.
"It can be challenging to incorporate sensors such as optical sensors [which measure heart rate] into electronic devices," says Apple in "Electronic Devices Having Optical Sensors With Curved Laminated Films."
"For example," it continues, "optical components for providing an electronic device with desired functionality may be too bulky or unattractive to incorporate into the electronic device."
As with all patent applications, this one makes an attempt to cover all possibilities by saying that it covers everything from a laptop computer to "a computer monitor containing an embedded computer," or "a wristband device, a pendant device, a headphone or earpiece device," and on and on. If it can house an optical sensor, Apple wants it covered by this application.
However, it's really about the Apple Watch. "The wearable device may have a wearable housing in which the optical sensor is mounted," it says. "During operation, light from the light source may pass through a transparent portion of the housing, may reflect from an external object such as a wrist or other body part of a user, and may be received by the photodetectors after passing through light control members."
"The light control members may be arranged in a ring with a center and may have curved shapes with concave surfaces that face the center," it continues.
This is the key part, the way that such optical sensors might be arranged and also curved, to take up as little space as possible. "Each light control member may be formed from a stack of laminated bent light control films," says Apple. "The light control films for the stack may be pressed into desired bent shapes using a lamination tool with curved surfaces."
Space within the Apple Watch is already at an absolute premium. However, this patent application is credited to Tyler S. Bushell, who has previously applied for patents regarding the Digital Crown.
One is to do with turning the Crown into a touch-sensitive area that recognizes gestures, while the other proposed making it function as a joystick. Both of these could free up space by removing the Digital Crown's moving parts inside the Apple Watch casing.