If you’re looking to buy an e-reader, you should wait a little longer. Color e-reader screens, like E Ink’s Advanced Color e-Paper version 2 (ACeP v2 or Gallery 4100) and TCL’s Nxtpaper technologies, may revolutionize how we read ebooks in 2022 and beyond. So, if you’re wondering why you should wait, here are the top six backlight-free technologies that will change how we read in the near future.
1. E Ink’s Gallery 4100: Great Color, Fast Black and White
E Ink’s Gallery 4100 e-paper technology is unusual because it has vibrant colors and can quickly refresh black-and-white text. However, many unanswered questions remain regarding its availability, technical specifications, and cost. Fortunately,
E Ink’s Associate Vice President, Timothy O’Malley, shared details on E Ink’s upcoming Gallery 4100 color E Ink display during a January 2022 interview.
Gallery 4100 Is a Working Title
While E Ink refers to its color E Ink technology as Advanced Color ePaper (ACeP v2), its working title is Gallery 4100. Gallery 4100’s name will likely change in the future when it reaches consumers. Currently, Gallery 4100 is only available as a development kit.
Color Ereaders Based on Gallery 4100 Could Be Years Away
As of 2022, the closest you can get to Gallery 4100 is the 13.3-inch Atelier development kit, which costs $800. Otherwise, there’s no information on when ACeP v2 technology will reach ereaders.
Interestingly, O’Malley mentioned that E Ink sells Gallery 4100 development kits. However, there’s a long lag time between when hardware development begins and when a final product reaches consumers. So while E Ink is actively working to reduce ACeP’s barriers to market, there’s still a ways to go.
ACeP v2 Color E Ink Is Designed for Ereaders
The big revelation is that a four-color pigment E Ink system is coming to ereaders. While E Ink declined to state any upcoming product release date, they did confirm specific features. The most important feature is fast-refresh:
“The refresh rate is impacted by the number of particles being moved within a capsule or Microcup®. In the video you referenced, the black and white images are only requiring the black and white particles to move, not the full four that are contained within the capsule.”
The video mentioned in the quote refers to a now-removed clip demonstrating ACeP v2’s color and black-and-white capabilities. The missing video showed that ACeP v2 can turn black-and-white pages similar in speed to Carta panels.
In 2022, Tim O’Malley further elaborated on ACeP’s fast refresh capabilities. While Gallery 4100 uses four pigments to generate color images, it only uses two colors to generate blacks. In other words, Gallery 4100 can rapidly increase refresh speeds by computationally simplifying the image it’s drawing. A black-and-white image has less complexity relative to color, so Gallery 4100 can render it more quickly.
ACeP v2 May Cost More Than Black-and-White E Ink Ereaders
Unlike E Ink and other technologies that use black-and-white pigments, ACeP uses four colors.
The added complexity causes the slower refresh speeds since whenever a color image is displayed on screen, the hardware arranges cyan, magenta, yellow, and white (CMYW) in elaborate and complicated combinations, which constitute an image. A black-and-white panel only needs to arrange two pigments on the screen. The reduced complexity means faster page turns, although color refreshes take considerably longer to refresh.
The added complexity may mean that ACeP v2 requires beefier hardware and more expensive manufacturing processes. As a result, early ACeP panels could cost a significant amount more than black-and-white E Ink. ACeP development kits, which are already available in digital signage products, cost hundreds of dollars.
If that’s an indication of what a consumer e-reader would cost, then it may remain unaffordable. However, if any color reflective screen ever makes its way into a Kindle, it’ll likely be ACeP because of its high color saturation and fast refreshes for black-and-white text. These characteristics make ACeP perfect for reading textbooks and comic books.
Gallery 4100’s Battery Life
Gallery 4100 consumes slightly more power than E Ink Carta. However, according to O’Malley, Gallery 4100’s power consumption is infinitesimally smaller than the Wi-Fi power drain. In other words, most users won’t notice any difference in battery life. So while the Gallery 4100’s complex, four-pigment system may require additional power, it’s a trivial amount.
ACeP v2’s Cost, Size, and Resolution Are Unknown
O’Malley declined to comment on the price, dimensions, or release date. However, we know that Gallery 4100 will cost more than a black and white E Ink display due to its complexity. The exact price difference, unfortunately, remains unknown.
2. E Ink Kaleido Plus
E Ink Kaleido uses color-filter array (CFA) technology to generate color. A CFA is a thin layer of colored polymer filter stretched over another panel, usually an electrophoretic panel, like E Ink. The multiple layers create a full-color display, although with diminished resolution compared to a standard E Ink panel. Unfortunately, CFA’s colors also aren’t visually appealing and have the appearance of Jet-Puffed Fruity Marshmallows.
Today’s best CFA panels have a color depth of somewhere around 4,096 colors, or High Color. However, besides having a limited color palette, Kaleido Plus panels have low color saturation. In other words, colors look washed out. However, in our review of the Onyx Boox Nova 3 Color, even with reduced resolution and weak color saturation, the e-reader isn’t bad. Unfortunately, it lacks the vibrancy you’d expect of a Kindle.
3. Display Electronic Slurry (DES)
DES technology looks an awful lot like E Ink Kaleido, except its color saturation is higher, and it costs less. DES uses a novel latticework of “cofferdams” for its black-and-white layer and a red-blue-green CFA layer to generate color. Because DES technology uses fewer elements in its display stack, it also has higher color saturation. Furthermore, because it’s simpler compared to E Ink, it’s also less expensive.
We reviewed an early color DES panel on the Reinkstone R1 color e-reader in 2021. While the color saturation is markedly richer than Kaleido, the DES panel suffered from numerous teething issues, namely a serious problem with image artifacts and ghosting. In fact, Reinkstone dropped the DES panel in the R1 and moved on to a second-generation version of the panel. As such, we don’t know what the final product will look like.
Other devices are slated to receive a DES panel, such as the Topjoy Butterfly. However, since DES technology is essentially a variation on Kaleido, it’s unlikely to make its way into the Amazon Kindle.
4. TCL’s Nxtpaper Mid With Reflective LCD
TCL announced a new reflective LCD (RLCD) technology at IFA 2020 called Nxtpaper. Unfortunately, TCL’s RCLD technology was delayed numerous times. Thanks to the pandemic’s impact on global supply chains, it seems to have been cast into Limbo. TCL declined to comment on the future availability of the Nxtpaper Mid tablet. Although video of the technology indicates good color saturation, even with the backlight turned off.
While TCL announced the TCL Nxtpaper 10s at CES 2022, the 10s isn’t an RLCD unit. It instead uses a standard LCD screen with reduced blue-light emissions.
It’s unknown whether TCL will ever release their Nxtpaper Mid tablet.
ClearInk’s reflective technology is based on electrophoretic technology, just like E Ink’s panels. Also, like E Ink’s Kaleido, it uses a CFA layer to generate color. However, unlike E Ink, it uses a single black pigment instead of a two-pigment system. ClearInk first announced its technology in 2016 but has since picked up partners such as Lenovo and display manufacturing giant Tianma.
ClearInk manages to do a few things that its competitors cannot: cost-efficient color video without requiring a backlight. Unfortunately, ClearInk seems to have fallen silent online despite its manufacturing partners. It has remained quiet since 2019, and as of 2022, it appears it hasn’t released a single product while E Ink has released several refinements of its Kaleido technology. Even so, ClearInk has several advantages over its competitors.
ClearInk Does Color and Video for Less Money
E Ink’s Triton was a first-generation color e-paper technology, but it never stood a chance of reaching Amazon’s Kindle. The Triton panel cost a fortune and suffered from a weak contrast ratio and slow refresh rates. In other words, it didn’t look good and couldn’t play video.
ClearInk, on the other hand, displays color at around 4,096 colors (High Color). This means it’s less vibrant compared to LCD and OLED panels. However, its video refresh rate of 33Hz (equivalent to broadcast television or YouTube) allows full-motion video. Here’s an example I shot at Display Week 2019:
The video and high clarity of ClearInk comes down to the type of black pigment it uses. Both ClearInk and E Ink create images using electrophoresis. However, there’s a big difference between the two. E Ink uses two pigments. The additional overhead of dealing with two pigments causes slower refresh speeds and choppy video.
ClearInk uses a single, smaller-sized pigment to create black and whites. The ink used in ClearInk, co-developed with Merck, is sharper and clearer than E Ink panels. According to Sri Peruvemba, former Head of Marketing at ClearInk:
“E Ink uses a two particle system to generate black and white. To generate white, E Ink uses a white particle to reflect light. Whereas, CLEARink only uses one particle—black—to generate [a] black state. To generate white, CLEARink uses a TIR (Total Internal Reflection) film on the front surface.”
The end result: higher contrast, lower power consumption, higher resolution, and even color video, when combined with a color layer.
ClearInk’s Power Consumption Is Higher Than E Ink
While ClearInk’s video variant consumes more energy than E Ink, its power consumption relative to LCD comes in around 80 to 90 percent less. In addition, it can display motion video with a refresh rate of around 33 Hz. A little choppy, but good enough.
Problems With Ghosting, Color Accuracy, and Waveforms
ClearInk isn’t a perfect technology. It suffers from issues with image retention, or ghosting, where portions of the display do not refresh. You can see a small amount of ghosting in the picture above. In 2019, ClearInk’s engineering team explained that issues with early prototypes caused the display imperfections.
Additionally, ClearInk panels have the same color accuracy as Kaleido Plus. It’s good enough for textbooks and comics but not enough for enterprise-class purposes.
And finally, like E Ink, ClearInk panels require special software and hardware to create and draw images on its screen. In other words, the hardware-level infrastructure and software techniques used in LCD technology are not fully compatible with ClearInk panels. ClearInk screens cannot just be dropped into a computer without writing special software.
However, Peruvemba mentioned that they are working on drop-in panel solutions for LCD screens. Meaning if they pull it off, manufacturers could simply swap out an LCD for a ClearInk panel without any added costs.
6. Tianma’s Reflective Color LCD
Tianma Micro-Electronics, one of the world’s largest display manufacturers, announced a reflective color LCD panel, known by its project name as Electrical Bag (almost certainly a mistranslation). Like most e-paper technologies, it doesn’t require a backlight but is compatible with the front lights used in most ereaders.
The panel is aimed at the educational market. As such, it comes in a 10.5-inch form factor, designed to read color textbooks. Unlike E Ink, reflective LCDs can display full color and video. But the trade-off is a limited color range and weak contrast ratio. For example, Electrical Bag has a 12:1 contrast ratio and a PPI of 191. It can also only do 11% of the NTSC color range, about half of its competitors. However, the price is low, and they can be dropped into almost any device with little effort.
An engineer at Tianma quoted a price similar to an emissive LCD for a 10.5-inch panel. The educational market, which caters to children, is an ideal product for reducing eyestrain.
Tianma claimed that, if any manufacturer were interested, the Electrical Bag would be available in 2020. Unfortunately, as of 2022, it seems to have never made its way into any products.
A Color Kindle in 2023?
Without question, the color E Ink technology most likely to reach Amazon’s ereaders is E Ink’s Gallery 4100. While E Ink Kaleido Plus and Wuxi WeiFeng Technology’s DES can display color, those colors are washed out and unsuitable for high-end devices. As such, Gallery 4100 is the only technology that seems to stand a chance of making its way into an Amazon e-reader.
While Amazon hasn’t shown any interest in color e-paper since it dumped LiquaVista, color ereaders could expand Amazon’s reach to the lucrative education market. Amazon has already tried to expand its reach to children with its Kindle Fire for Kids.
A backlight-free Kindle aimed at children may soon become a reality. But until then, we’ll have to wait and see what new color e-reader tech hits the market.
Here’s everything you need to know to decide whether to buy an Amazon Kindle or Barnes & Noble Nook ebook reader.
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