O-Film demonstrated a periscope lens module for smartphones that offers continuous zoom instead of being locked at a specific focal length like current periscopes are. And the module is only 5.9 mm thick.
The module can smoothly go between 85mm and 170mm (in 35mm equivalent) with the lens aperture changing from f/3.1 to f/5.1. To put that in perspective, the Xperia 1 II has a 70mm tele lens, the Huawei P40 Pro a 125mm lens and the P40 Pro+ a 240mm lens.
O-Films module will provide 3x to 7x magnification compared to a typical wide camera. The company claims that it can also manufacture periscope designs with 3-5x, 5-8x and 3.5-9.5x zoom ranges.
Anyway, this module features the familiar prism, which is used for OIS. A piezoelectric motor smoothly and accurately drives a 3-lens assembly forward and back to reach the desired focal length. The autofocus mechanism moves with the lenses.
Since current smartphones have cameras with locked focal lengths, they use digital interpolation for in-between zoom levels, switching from the wide to the tele lens as needed.
Continuous zoom will offer higher quality images at these intermediary levels. It will also make periscopes more useful as current designs with 5x magnification limit you to shooting only faraway objects.