For the grayscale, I'm guessing each physical display would need to be individually calibrated? I also wonder whether the calibration is sensitive to environmental factors, i.e. gets out of whack if the display is too hot or too cold.
It would be interesting if the driver could sense whether the pixel had fully transitioned or not, allowing it to measure transition time and accurately generate greys.
But if a display only officially supports black & white, its driver just needs to know the duration of the slowest transition across the operating temperature range. It could then use that duration for all transitions, regardless of the temperature.
For the grayscale, I'm guessing each physical display would need to be individually calibrated? I also wonder whether the calibration is sensitive to environmental factors, i.e. gets out of whack if the display is too hot or too cold.
There has to be a reason the e-ink industry hasn't done this yet...