Shameful but true: I own and watch a CRT TV, in all of its big, boxy glory. This might be a sore spot for someone who has recently immersed herself in the study of Displays & Screens, but my reasoning is solid. The TV works, the display area is large, and the picture is beautiful. Also, I invested a fair amount of money in a delightful cabinet to house the set and its peripherals. This TV and cabinet have a few more years to go before I can justify the investment and annoyance of rearranging my living room to accommodate a flat panel display.
So, in light of my adherence to the CRT, it makes sense that I’m happy to report that the old tube technology is finding new life in a new type of display called laser phosphor display. LPD appears to have some of the advantages of more modern displays, but with a fraction of the power requirements. Both CRT and LPD raster images onto a phosphor, but where a CRT uses an electron beam, guided by a magnetic field, to activate the phosphor coating, LPD uses lasers, guided by a mirror.
Wade Roush, a friend and former Technology Review colleague, broke the story of Prysm, the LPD startup last week. I’ll be writing a story for Technology Review about the technology, adding some perspective from display experts and explaining a bit more of the technology. Stay tuned!
I got it in college and went on to buy an expensive (and beautiful) cabinet to hide it in, and just haven’t bothered to upgrade
(Updated 12:08 p.m. January 8, 2010 to include quantum dots as an upcoming display technology)
My survey of display tech, “The Hunt for the Perfect Screen,” was posted at Gizmodo a couple of weeks ago. It was a fun piece to write because it helped me see how much I’ve actually learned about screens like holographic systems, energy-efficient LCDs, bright and beautiful OLEDs, and lightweight plastic displays and their manufacturing. Most of it is fairly mind-blowing stuff. And it reminds me why I’m happy to be a technology reporter–I get to spend my time looking at the future.
The hardest part of writing the piece, unsurprisingly, was pruning the prose. There are a lot of specific technologies that I left out for the sake of flow and length. Below is a short list of topics that didn’t make it into the article.
Up-and-coming e-reader technologies such as MEMS devices (mirasol from Qualcomm) and electrowetting (from Liquavista, a spinout of Philips). I wrote a fairly comprehensive summary of future e-reader technologies for The Economist here.
Quantum dots–tiny nanocrystals that emit spectrally pure light–are being used to improve the efficiency of LCDs and could find their way in OLED screens down the road.
I plan to expand on some of these omitted topics in the future.
And now for a reporting outtake. Below is an anecdote on how a company I mentioned in the Giz article got its name.
On the naming of Phicot: The company that’s trying to commercialize HP’s plastic electronics manufacturing process is called Phicot. When I asked Carl Taussig of HP what Phicot means, he told that one of the researchers has a son who, when he was an infant, would pick up objects and call them all the same word, something that sounded like “phicot.” A toy truck? Phicot. A book? Phicot. A piece of food? Phicot. The parents started to worry about the child’s intelligence, says Taussig. But when the boy grew up and was able to enunciate better, they learned that he was simply saying, “Look what I’ve got.” Which is also something you might say to people if you have a display manufactured by the company. Cute.
Quantum dots are tiny nanocrystals that emit pure, bright light. For decades they’ve mainly been lab curiosities, but now QD Vision, an MIT spinoff, is using quantum dots to improve the color and efficiency of liquid-crystal displays.
I caught up with Seth Coe Sullivan, co-founder and CTO of QD Vision, at the Printed Electronics 2009 conference last week in San Jose. We talked about quantum dots in lighting (click here for the Q&A) and in LCDs. Below is an edited Q&A with Sullivan about quantum dots for LCD backlighting.
Kate Greene: Quantum dots will be in lighting products early next year. What’s next?
Seth Coe Sullivan: In 2011, we’ll be launching a display product. It’s still a quantum light optic, but it’ll be augmenting LED light in the backlight of displays. We’re basically doing spectral engineering, designing the spectrum of a light source to be perfect for the application. With solid-state lighting, we are focusing on the human eye’s perception of white. With displays we’re focused on creating red, green, and blue, but in particular red and green color channels in LCD to give a high color gamut, high power efficiency, while again reducing cost because we’re saving manufacturers LEDs.
KG: So where does the optic fit in an LCD?
SCS: If you look at an LCD today, you’ll see that they typically use white LEDs as a backlight. It’s a blue chip with yellow phosphor. So what happens is you get this nice broad yellow peak that fills out the spectrum and make it look roughly white. Then what you’re doing is putting it through a color filter because you want separate red and green channels. There’s a little red light in the yellow phosphor, and there’s a little bit of green light in yellow phosphor, so what LCD manufacturers are doing is using really spectrally broad color filters to let as much light through as possible. It hurts color quality, or color gamut in this case.
KG: Quantum dots replace filters?
SCS: No, they’re still going to use filters, we’re just going to take out the yellow phosphor, which is adding very little value but solving a need, and adding red and green quantum dots. It’s still going to be white light, but it’s going to tri-chromatic white that’s optimized for filters to maximize the throughput through the filters, as opposed to bi-chromatic light that’s getting chopped into tri-chromatic by the filters.
KG: If you did spectral analysis of your laptop backlight, it’d look blue and yellow?
SCS: Before the color filters, yeah.
KG: And then after the color filters it’s red, green, and blue?
SCS: Yeah. You’re taking this broad band and chopping it into pieces, and it’s extremely lossy. The white LEDs don’t put the photons where LCD really need it.
KG: How does this get integrated into manufacturing of an LCD.
SCS: Right now LCD makers buy white LEDs, integrate them into light bars, which is a bunch of LEDs on a strip, and those are coupled to the edge of a light guide plate which spreads the light. What we do is sell a quantum light optic that goes between the blue LEDs now and the light guide plate. So blue light gets converted into tri-chromatic white light and then gets couple into the light guide.
KG: They just have to buy blue LEDs instead of white LEDs with phosphor?
SCS: Yes. We aren’t selling the integrated LED. We’ll sell the optic.
KG: What sort of improvements can using a quantum light optic give to an LCD?
SCS: There’s a potential of 30 to 40 percent increase in power efficiency. Color gamut goes from about 80 percent of the standard gamut to over 100 percent. So all of a sudden your TV is as good as your CRT [cathode ray tube] was 10 years ago in terms of color. And there’s manufacturing cost savings to LCD makers, which is a big deal. Those guys operate at such thin margins, even giving them a few points is doubling their profitability potentially.
KG: Which LCD companies are you working with?
SCS: I can’t give any particular names, but we’re working with three of the five major LCD companies.
KG: It’s a clever to improve displays like this without re-engineer the entire device.
SCS: The display industry is completely motivated by cost, so it’s got to be really simple. What’s so compelling for us is that the materials we’re developing in solid state lighting—the packaging, the technology, the manufacturing processes—are going to be identical. For a small company chewing off very big markets—and both lighting and displays are $100 billion markets—it’s important that there’s a lot of synergy in terms of processes, materials, and manufacturing.
KG: Lighting and displays both use quantum dots that are activated by light, not electric current. What about full quantum-dot displays that are powered by electricity?
SCS: They’ll largely be on the military side for the Department of Defense, where they’re willing to perhaps pay a little more to solve a critical life-saving need. We’ll do that as opposed to competing right up against LCD. The OLED [organic light-emitting diode] guys are learning just how hard that is. How many decades have they been going at it? They’ve got a compelling technology, but cost, manufacturing scale, and building fabs it’s hard to compete with LCD.
This is the second of two Q&As with Sullivan about QD Vision products. The first Q&A focused on improving lighting with quantum dots. For my story in Technology Review about quantum dots for LCDs, go here.
QD Vision, an MIT spinout, is commercializing quantum dots, tiny crystals that emit bright light of a particular color. Because quantum dots shine at specific colors, a layer of them can be added to an LED to alter its original color. This is exactly QD Vision’s first product: quantum dots that makes white LED lights, famous for their erie hue, look better.
The quantum dot lighting solution is relatively simple: Adding red quantum dots to a white LED makes the resulting white light appear warmer. Light from the LED gives electrons in the quantum dots an energetic boost for a short time; when the electrons return to their lower energy state, they emit a photon, a process called photoluminescence. (Photoluminescence is in contrast to electroluminescence, in which electric current, not light, excites electrons.)
I caught up with the founder of QD Vision, Seth Coe Sullivan, at the Printed Electronics 2009 conference in San Jose last week to ask him a few questions about lighting. Below is an edited version of our conversation:
Kate Greene: What quantum dot products are you selling right now?
Seth Coe Sullivan, founder of QD Vision (front)Seth Coe Sullivan: Today, we’re commercially shipping a quantum light optic. It’s essentially a light-emitting filter: a plate of glass with quantum dots printed on top. We sell it to a couple of customers. One is a fixture company, and one is a lamp company called Nexxus. They make Edisonian-mount lamps, so you can screw the lamp into the same mount you screw an incandescent bulb into. The Nexxus lamp used to have a diffuse filter plate on the top of it. With our product, they just take that plate out, and put the quantum light optic in its place. You get to transform the color without paying any price in terms of efficiency. You have the color of incandescent lighting with the efficiency of LED lighting.
KG: The optic is emissive, and so it doesn’t decrease efficiency like a filter?
SCS: Right. We’re using blue photons from the LEDs and making red photons from the quantum dots. In theory you could make the lamp four times as bright by going from blue to red. But we’re not using all the blue light from the LEDs. We’re just making a little bit of red to tweak the spectrum.
KG: Okay, give me a quick definition of quantum dots.
SCS: A quantum dot is a semiconductor nanocrystal that we synthesize in a chemical solution. When you make semiconductors very small, the quantum physics dominates the conventional semiconductor physics. So size matters. A quantum dot, made of the semiconductor cadmium selenide, that is six nanometers in size emits red light, one that’s four nanometers emits green, and one that’s two nanometers emits blue.
KG: How long have they been around?
SCS: They date back to the 80s. But there’s really been a series of improvements of efficiency and stability so that all of a sudden quantum dots have crossed the line in commercial relevance. The first applications were all in biology. They were used to tag sections of cells and other things. Then there was a Christmas tree light product that predated us. It’s neat, but it doesn’t provide any actual value to the world. Still, it was great to see them put something on the market.
KG: But in terms of a major commercial product, QD Vision has the first?
SCS: We really are the first to put something in a mainstream market where you’re adding value to the world. By making LED lighting, which is the most efficient lighting technology in the world, something that’s pleasing to consumers, all of a sudden you can drive adoption of LED technology. LEDs make up less than one percent of lighting right now. Philips talks about it being 80 percent in 2020. That’s massive growth in the next 10 years, but in order for that to happen, people have to want to buy them. It’s not enough to be efficient. They have to look good too. We think we’ve solved that problem, and we’re talking to all the major players to build quantum light optics into their products.
KG: What’s the change in cost to add a quantum light optic?
SCS: It’s actually a reduction in their manufacturing cost. Nexxus is actually going to offer products at same price, but that just means they’ve improved their margins by increasing their efficiency. When you look at these things, you always need to do an apples-to-apples comparison. I’m comparing our product, with the high color quality that it has, with trying to make the same color quality with any other technology. Because we’re doing that with roughly 30 percent more efficiency, you’re using 30 percent fewer LEDs to produce the same number of lumens. By putting in a quantum light optic instead of 30 percent more LEDs, you take all that cost out. When you add the cost of quantum light optic in there and the net result should be reduction in main cost.
KG: Can I buy a quantum-dot light today?
SCS: Almost. We are shipping to our customers. Our customers then have to make a lamp or a fixture, sell them to their distributors, and then their distributors have to sell them to end customers who have to install them. Right now that hasn’t sold all the way through. For example, the Nexxus product will be the first quantum lighting product sold on bulbs.com. So probably in late January or early February you’ll be able to go to that site and purchase a Nexxus array lamp with a quantum light optic inside.
KG: Will it be expensive?
SCS: I’m told the retail price will probably be $100.
KG: How does that compare to other LED lighting?
SCS: It’s extremely competitive within LED lighting. LED costs more than other lighting technologies. An incandescent bulb of the type we’re talking about might be $3. A compact florescent might be between $5 and $10, so a $100 light bulb is an investment. But this bulb isn’t meant for you and me, in our homes today. It’s for people who look at total cost of ownership model when they install lighting. So if you’re a building owner, you look at the cost of bulb and also the electricity to run it, the maintenance cost to replace it, and the future bulbs you’re going to have to buy. If you look at total 50,000-hour life of our product, you’ll need five compact florescent bulbs or 25 halogen or incandescent bulbs. Then you add in the cost of the guy climbing the ladder to change the bulb, it pays you back in 12 to 18 months.
KG: What’s next for quantum-dot lighting?
SCS: With existing customers, we will expand the product line offering. So we do that in terms of different colors temperatures offered. 2700 K is the temperature that describes what an incandescent bulb produces. That’s what we’re offering now. But we can also do 3000K, 3500K, 4100K products.
KG: Who are your other customers?
Seth Coe Sullivan (back)
SCS: We’re working with all the lighting majors. Lighting is an extremely fragmented market. We do have a lot of different customers that are in the design cycle to launch products in 2010.
This is the first of two Q&As with Sullivan about QD Vision products. The second Q&A will focus on improving liquid-crystal displays with quantum dots.
The digital camera revolution was a little rocky for Polaroid, a company famous for an iconic film camera that prints photos instantly. But thanks to the invention of a new type of thermal printer, the company now has a instant digital camera, the Pogo. I’ve had the chance to play around with one for a couple of weeks* and I have some thoughts. First the bad:
The camera is big and boxy, much like a Walkman from the ’80s.
The 2″ x 3″ photo paper is loaded into the body of the camera, but when you shake the camera the paper moves around. Technically this isn’t a problem, but it’s still disconcerting to hear things moving inside.
The user interface is awkward and slow compared to the other cameras–Pentax, Canon, and Nikon– that I’m used to using.
Now the good:
It is AWESOME to be able to print out a picture and give it to a person on the spot. People are so used to having their picture taken and resigning themselves to the fact that they may never see it again. Maybe it will be posted on Flickr or Facebook, maybe not. It’s been surprisingly fun and rewarding to give a physical picture to someone immediately.
These cameras aren’t very well known yet, so there’s a nice novelty to them.
The photo paper is relatively cheap. You can buy a pack of 30 for $10.
I’ve found that I enjoy thinking of fun and clever uses for the pictures like putting together flip books or hiding pictures of me making funny faces around the house for my partner to find.
My main recommendation to Polaroid is to change the form factor of the PoGo. I understand that the camera has to be a little bigger than the average point-and-shoot to accommodate the internal printer and paper, but why not have a little fun? Urban Outfitters sells bigger, vintage-looking digital cameras that the cool kids really love. Imagine how much more they’d love these cameras if they printed photos too!
*Disclosure: the PoGo sells for $199, but I got mine as a free gift for participating as a judge in a design contest for the Zink thermal printer.
Shameful but true: I own and watch a CRT TV, in all of its big, boxy glory. This might be a sore spot for someone who has recently immersed herself in the study of Displays & Screens, but my reasoning is solid. The TV works, the display area is large, and the picture is beautiful. Also, I invested a fair amount of money in a delightful cabinet to house the set and its peripherals. This TV and cabinet have a few more years to go before I can justify the investment and annoyance of rearranging my living room to accommodate a flat panel display.
