A lesson on the one trade every e-reader screen makes: a page that holds itself without power and uses room light, in exchange for being slow to change. It covers the pigment capsules inside, refresh recipes and ghosting, pen latency, the difference from reflective LCD and lit phone screens, four device shapes, and recent releases and price changes. Episode page & show notes Visit website One screen, one bargain An electronic paper page holds itself without power and is lit by whatever light is already in the room; in exchange it is slow to change. Inside the layer are millions of clear capsules, thirty to a hundred microns across, filled with oil, negatively charged white titanium dioxide and positively charged carbon black — soot and white paint shoved into position by electrodes, with roughly sixteen grey levels made by stopping the pigment part way (how electrophoretic displays are built, and the original E Ink patent). The pigment stays put when the voltage stops because short-range stickiness beats gravity at that scale, additives damp the random jiggling, and the charge around each particle stays balanced. That bistability — not a bigger battery — is where every long-runtime claim comes from. The cost: particles must be dragged twenty to forty microns through oil, taking tens to hundreds of milliseconds, and slowing further when cold. A full clearing refresh shakes the particles loose, drives the whole panel to black then white — that is the flash — then places each pixel, in about four hundred to a thousand milliseconds (the shake–erase–drive waveform). Skip those steps and you get partial refresh at roughly two hundred milliseconds, or around a hundred for panning — paid for in narrowed contrast, faked speckled greys, and ghosting from unfinished pigment, stuck particles and ions piling against capsule walls. No setting escapes the curve. Handwriting survives only by bypassing the normal drawing path: pen-first makers claim under twelve milliseconds, independent high-speed video puts real note-takers at seventeen to thirty, while ordinary Android drawing apps land between eighty and over a hundred and fifty. Video and smooth scrolling stay bad. Reflective LCD, by contrast, twists in place in single-digit to low-double-digit milliseconds, runs at video rates, and loses the picture when power stops. Three shapes cover nearly every screen offered: reflective and bistable and slow, reflective and fast, emissive and fast. The devices then sort into four kinds — closed reading appliance, open reading system, general Android e-paper, and pen-first note-taker — with no recommendation made here, because resolution, colour, light, grip and file transfer have not been covered yet. Three checks on any device you can touch: time one page turn and note whether it flashed; change part of the screen and hunt for remnants; write one line and watch the gap between nib and ink. Four devices and a price rise Onyx is shipping the Note Mini C and the Note Air6 C — the latter keeping the Air5 C screen, body, memory and battery with a new processor and software. The fifty-eight gram, four-inch Picco is announced only, due before year end. Amazon's base prices have risen: entry Kindle at $149 with lockscreen ads, $169 without, Paperwhite at $199. iReader's Air 3 Pro ships in China, import only, no local warranty.
