Pixel Qi: The LCD Screen That Could Finally Kill Paper For Good

Mary Lou Jepsen has created massive holograms and cheap laptops for the developing world. Now she’s rethinking the LCD screen, leading the way to the next great gadget: an e-reader to replace your laptop

By Lauren Aaronson Posted 01.12.2010 at 2:01 pm 16 Comments

Pixel Qi : Mary Lou Jepson's hybrid computer screen blends the best aspects of both laptop and e-reader displays John B. Carnett

For Mary Lou Jepsen, getting an MRI is not unlike getting a massage—a relaxing ritual, a rare slice of time when no work can possibly be done. I’m accompanying Jepsen to her doctor’s appointment at Massachusetts General Hospital because it’s the only few hours she can fit me in. She’s in Boston for three days, in between trips to her Sausalito, California, houseboat and her apartment in Taipei, Taiwan, and she’s booked back-to-back with appointments. Yesterday she had a meeting with the team at One Laptop Per Child, the nonprofit she helped create and with which she still collaborates on new computer designs. Today she’s talking with her doctor about the medicine she needs to take to stay alive, after a tumor nearly killed her 10 years ago. Tomorrow she will appear at the Boston Book Festival in a debate about the future of reading, along with top executives from Sony and Google.

While Jepsen gets her brain scanned, I sit in the waiting room and guard the tote bag that contains the reason her life is so frenzied: a 10-inch slab of glass that, she says, merges the best of computers and e-readers into a single screen.

Turn on the store-bought tablet PC that Jepsen’s prototype screen sits in—she removed the old screen with a screwdriver and swapped hers in—and it looks and acts like any LCD screen, because it is an LCD, only better. LCDs display color and video, but they kill battery life. Electronic ink is more energy-efficient and paper-like, but it’s black and white and is frustratingly slow to load a new page. Jepsen’s screen combines the best of both technologies. Flick a switch, and the bulb that makes the screen glow will dim. But instead of going dark, only the colors will fade. That’s because in Jepsen’s screen, ambient light can substitute for backlight, bouncing off the mirror-like material that Jepsen has added to each pixel to reflect shades of black and white. With the lamp completely off, the screen, called 3Qi (pronounced “three chee,” as in qi, the Chinese word for “spirit,” and a geeky pun on the 3G wireless network), displays letters as crisp and readable as those on Amazon’s Kindle. In this mode, 3Qi uses about one fifth the power of a normal computer screen, Jepsen says. And unlike the E Ink–based Kindle or any other widely available e-reader, it still does everything a regular LCD does, including play videos.

As Jepsen will say in her talk tomorrow, “The future of reading is screens.” She puts it to me more bluntly: “Books are toast.” She’s not talking about reading, just dead-tree delivery, and there’s evidence to back her up. Between January and September of last year, $112.5 million worth of digital, downloadable books were sold, up from $7.2 million during the same period five years earlier. Since the introduction of the Sony Reader Digital Book in 2006 and the Kindle in 2007, the number of e-readers sold in the U.S. has more than doubled every year—an estimated one million in 2008, three million in 2009, and a projected six million this year. According to one forecast, that number could rise to 77 million worldwide by 2018.

That may be hard to believe given the single-task capability of current e-readers. But once a screen arrives that combines the best of laptops and e-readers into a single, affordable package—once a flip of a switch can transform your high-definition-movie-playing color laptop screen into an e-book with enough battery life to last a trans-Pacific flight—then things get more interesting. Laptops could become simple flat touchscreens, and e-readers as we know them could eventually become obsolete. If the future of gadgets is in the screens, Jepsen is trying to write that future.

So are plenty of others, of course. And this could be the year the leaders in the display race pull away from the pack. The cellphone-chip giant Qualcomm; the current e-reader display leader, E Ink; and at least one other major player are set to release next-generation e-reader screens by 2011. But Jepsen’s hybrid screen is likely to be the first and the least expensive of the bunch. Her company, Pixel Qi, which is based in both Silicon Valley and Taipei, will, by the time you read this, have started a run of millions of screens. Although Jepsen won’t name brands, she says these will soon appear in netbooks, tablet computers and dedicated e-readers.

The Pixel Qi screen I’m guarding in the hospital waiting room is one of a few thousand that currently exist. Jepsen had shown it to me earlier in the day, so I restrain the impulse to pull it out of her bag to do my reading. I knew that in the black-and-white mode, the screen makes reading the newspaper as easy on my eyes as, well, the paper itself. Because the black-and-white portion of each pixel is so large (and because parts of that little pixel-portion can be turned on and off individually), the resolution in black and white is nearly 200 dots per inch. It’s remarkable, and I understand why despite being an underdog in this race—a woman doing business in Asia, competing with some of the giants of the electronics business, all the while managing a life-threatening medical condition—Jepsen is on the cusp of something big. And why she’s so busy fielding interest that she can step out of an MRI visibly relaxed. “That’s the most time off I’ve had in a long time,” she says as she steps out of the imaging room.

How It Works

3Qi combines two kinds of displays—an ordinary color LCD and a low-power, high-resolution black-and-white version—into one package. Here’s how it pulls it off:

Pixel Qi: How It Works: Graham Murdoch

Creating Color
Part of each pixel acts like one in a normal LCD screen: A backlight [A] shines through a layer of liquid crystals [B]. The crystals control how much light gets through, depending on how they shift their orientation when zapped with electricity. The light that makes it past the crystals passes through red, green and blue filters [C], which tint and combine the light to create the colors on your screen.

Bouncing Black and White
Turn the energy-sucking backlight down, and the pixel reflects light instead of producing it. Ambient light [D], whether from a lamp or the sun, enters the display and hits a large part of the pixel that’s covered in a mirror [E]. The beams bounce back out through the liquid crystals, which change the brightness of the light that escapes, just like in the color mode. But instead of shuttling through color filters, which absorb and dim rays, that light exits through an empty space—so you see it as white, black or one of 254 shades of gray in between.

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