Kaleido 4 color e-paper makes PDFs and notes look sharper

Kaleido 4 improves three things at once: color, brightness and contrast. E Ink, which announced the screen on October 15, 2026, says it doubles the color gamut volume of the previous generation to more than 40K. Color gamut is the range of colors a screen can show. E Ink gives no unit for that figure, so it is not a count of colors, just a sign the range is twice as wide.

White reflectance, how much light the white parts of the page bounce back, goes up by 15%. That matters because e-paper has no backlight shining through it; a whiter page looks more like real paper. Contrast, the gap between the darkest blacks and brightest whites, rises by 50%.

Together these changes are meant to fix the main complaint about color e-paper: text that looks a little gray and grainy compared with a black-and-white screen. E Ink says the new panel reduces that grainy look, so charts, slides and diagrams come out clearer.

E-paper is slow by design. Each pixel is made of tiny charged particles that physically move, which is why page turns flash and scrolling stutters. Kaleido 4 uses new algorithms that let it play video at up to 18 frames per second.

That is still far below a phone screen, but it is a real step for e-paper. Most color e-paper devices on sale today use Kaleido 3. Bigme rated its Kaleido 3 tablet, the S6 Color+, at 12 frames per second. Going to 18 means short animations and educational clips should look less choppy, even if nobody will be watching movies on one.

The panel also has a new oxide TFT backplane. That is the layer of tiny transistors behind the screen that switches each pixel, and the new one handles higher voltages so the screen can refresh faster. E Ink also redesigned the front light, the built-in glow you use in the dark, to make colors look more natural.

The first product with Kaleido 4 is the M10C II, a smart e-paper notebook from Hanvon Technology, a big e-reader brand in China. It runs on a Qualcomm octa-core chip with 4GB of RAM and 128GB of storage.

Page turns and scrolling are 27% faster, according to E Ink. That comes from pairing the new backplane with Hanvon’s own timing controller chip, called the T2000, and a screen-driving method Hanvon calls Enhanced Pressure Floating.

For writing, the notebook comes with a pen that needs no battery and senses 8,192 levels of pressure. The glass on top is finely etched to cut glare and to shrink parallax, the small gap you see between the pen tip and the line it draws. Hanvon also adds handwriting-to-text recognition, voice recording, AI office apps, cloud syncing for your book library and a mode that resizes third-party apps to fit the screen.

Hanvon’s vice president Wang Jie said the company wants to move color e-paper beyond reading and into work such as reviewing technical documents and taking meeting notes.

For now, nothing changes for most readers. The M10C II is the only Kaleido 4 product announced, and there is no price or release date for the US, UK or Canada. A week after launch, even the price and release date for Japan were still unknown.

The bigger impact will come when other brands pick it up. Brands such as Onyx Boox and Bigme already sell tablets with Kaleido 3, and Amazon sells its own color reader, the Kindle Colorsoft. None of them has announced a Kaleido 4 model yet.

Here is what to keep in mind if you are shopping:

• Buying now: any color e-reader or tablet on sale today uses older color e-paper, usually Kaleido 3. It still works well for books and comics.
• Waiting: if you mostly read color PDFs, charts or textbooks, the jump in contrast and color range is the upgrade you would notice most.
• Checking specs: look for Kaleido 4 named on the spec sheet. Brands usually list the screen generation.

E Ink is pitching Kaleido 4 for more than novels. Its chairman and chief executive, Johnson Lee, said color e-paper has to do more than simply add color. The company points to classrooms and offices, where people now load PDFs, slide decks, data charts and engineering drawings onto e-paper devices.

Those uses expose the weak spots of older color screens. A gray-ish chart with faint colors is harder to read than plain text, and slow refresh makes flipping through a long report tedious. Kaleido 4 targets exactly those problems, which is why the first device is a work notebook rather than a book reader.