Onyx Boox Tab Ultra PWM measurement
The Onyx Boox Tab Ultra is the premiere large note-taking e-reader from Onyx and it has an extremely eye-friendly e-Ink Carta display with no PWM at any brightness level. This device's frontlight doesn't get as bright as smaller Onyx products and has deeper modulation, but also runs at a higher frequency than those devices.
Visually measured by camera at 1/6400 shutter speed. Opple Light Master IV used for graph measurements.