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Rapefruit · 09-11-2009, 03:28 AM

Thanks for the information! Then I am lucky, indeed: I notice very slightly more ghosting but so little that I wasn't sure wether it hadn't been the same with the old screen. Maybe, somebody on the other end was aware of the waveform issue and selected a display with similar characteristics?

I'm not going to try to mess with updating it, but could you elaborate a little more on the wave form? I found this here:

The Waveform
The electronic ink in the display needs to be driven. This driving algorithm is called a waveform. It is a wave or sequence of different voltages that repel or attract the white or black particles in order to pull either the white or black particles to the top. If the waveform only pulls the particles shortly white and black get mixed, which we perceive as grey.

So, does having a (slightly) off waveform mean I get wrong shades of grey? And wouldn't you expect the driver to have some safety margin on the "full white" and "full black" sides to ensure turning completely under all conditions? I expect the eink to behave differently depending on temperature (and thus viscosity of the content of the capsules) and you already would need a safety margin to ensure full contrast under all conditions.

09-11-2009, 03:28 AM	#5
Rapefruit Member Posts: 13 Karma: 98 Join Date: Aug 2009 Location: Neuss, Germany Device: Hanlin V3 (64MB)	Thanks for the information! Then I am lucky, indeed: I notice very slightly more ghosting but so little that I wasn't sure wether it hadn't been the same with the old screen. Maybe, somebody on the other end was aware of the waveform issue and selected a display with similar characteristics? I'm not going to try to mess with updating it, but could you elaborate a little more on the wave form? I found this here: The Waveform The electronic ink in the display needs to be driven. This driving algorithm is called a waveform. It is a wave or sequence of different voltages that repel or attract the white or black particles in order to pull either the white or black particles to the top. If the waveform only pulls the particles shortly white and black get mixed, which we perceive as grey. So, does having a (slightly) off waveform mean I get wrong shades of grey? And wouldn't you expect the driver to have some safety margin on the "full white" and "full black" sides to ensure turning completely under all conditions? I expect the eink to behave differently depending on temperature (and thus viscosity of the content of the capsules) and you already would need a safety margin to ensure full contrast under all conditions.