Thanks to a team of scientists from CSIRO, the University of Melbourne and the University of Padua in Italy, the changes we’ve seen in the size of televisions and mobile phones over the past decade may seem small when compared to the wafer-thin televisions and lighting panels promised under new research into 'printable lasers’ .
The print laser technology would also dramatically cut manufacturing costs and improve the colour display of television and mobile phone screens.
In this podcast Dr Jacek Jasieniak from CSIRO Materials Science and Engineering explains the research and its possibilities, including light panels, roll up televisions and the production of printable solar panels.
Glen Paul: Hello, and welcome to CSIROpod. I’m Glen Paul. Looking back even over the past ten years we’ve seen some amazing changes in appliances such as televisions and mobile phones, going from the big and bulky to the thin and streamlined. And just when you thought your new LED TV screen was the thinnest thing around, along comes a team of scientists from CSIRO, the University of Melbourne, and the University of Padua in Italy, with new research that could see televisions rolled up like newspapers.
The scientists have come up with a way to print lasers that could one day be used to create wafer thin televisions and lighting panels. Doctor Jacek Jasieniak, from CSIRO Materials Science and Engineering, is one of the scientists involved and joins me on the line. Jacek, this sounds very sci-fi, printing lasers into screens and getting light to do what you want it to do sounds pretty tricky. Just how tricky is it?
Dr Jasieniak: It is pretty tricky. What we’re actually trying to do is harness the benefits of nanotechnology and combine materials science with existing printing technologies, so it’s really a multifaceted approach to actually developing a technology. So it’s extremely tricky.
Glen Paul: It sounds like it. So how do you do it, how do you get a tiny laser to turn into a pixel, or...
Dr Jasieniak: Yeah. To get a laser, what you actually need is you need to trap light, and you need to build up the intensity of that light in a very confined space. OK? And so what we try and do is we print basically a nanostructure on a surface that is capable of trapping that light. Now if you can imagine a laser pointer as such, you know you hold it and it emits light in a particular point, now what we do is when we take a sheet of say plastic or glass we nanostructure the entire surface on that glass, and then what we do is we deposit a material that is capable of producing that laser light.
And so because the entire surface is actually nanostructured, what that means is that every single point on that piece of plastic or paper can act like an individual laser source.
Glen Paul: Righteo. But how do you get these nanoparticles to emit different colours?
Dr Jasieniak: These particular nanoparticles are made up of semiconductor material, and semiconductor’s are very nice because what they do is they can absorb light or be able to conduct electricity, but they will eventually transform that light or electricity and give off light. And so any specific semiconductor will give off light of a different colour, and so what we do is we try and utilise quantum mechanical effects to change that colour.
Now what I mean by that is that when you make a semiconductor very, very small, nanometre in size, and you actually begin to change the actual size of those nanoparticles, what tends to happen is you increase the energy that gets stored in these particles. So you can imagine if you’re an ice-skater and you’ve got your arms all the way out, you’re spinning at a particular speed, when you bring in your arms you naturally move a lot quicker, so your overall kinetic energy is actually increasing.
And that’s exactly what we do in the materials science. So we start off with a particle which is very, very big, and we make it smaller, and smaller, and smaller, basically the energy, much just like the ice-skater, it gets pulled in and is enhanced. So we’re actually enhancing the kinetic energy of our nanoparticles, and so that basically allows us to shift the colour that’s being produced by a semiconductor, from something that’s low in energy to something that’s higher in energy.
And so if we choose something that’s emitting, for instance, in the near infrared, we can actually shift the colour that’s being produced by these particles from something that’s in the infrared to something that’s higher in energy, and what’s higher in energy is all the colours that are giving off in the visible, so we can do red, we can do orange, yellow, green and blue.
Glen Paul: How do you create this kinetic energy in the first instance?
Dr Jasieniak: Well you can do it in two ways. The easiest way is to actually shine some light onto the nanoparticles, so the light’s absorbed by the nanoparticles, and that creates that kinetic energy that’s stored inside. Or the other way is to actually inject charges into the nanoparticles. Now that’s a lot more difficult, and that’s something that we’re trying to capitalise on at the moment, but that’s the second way.
Glen Paul: Now you mentioned there as the first option light being able to produce this kinetic energy. That would open the way then for printable solar cells. Is that something that you’re also looking into?
Dr Jasieniak: It is indeed. So using the same types of technologies, what we’re really trying to do is develop technologies that are printable, whether they would be light panels or solar cells. I mean they both use very similar processes. And so for solar cells what we want to do is we want to absorb as much of that light, but instead of giving off that light in the form of say a laser emission or something like a pixel for a TV, we actually want to transform that light into electricity. And so we want to take that kinetic energy that we were discussing before and just separate it into charges.
Glen Paul: Well there certainly seems like there is a lot of options there for this type of technology in the form of television screens, and printable solar cells, and light panels you could stick up on the wall. Is this the future that you see?
Dr Jasieniak: I think definitely that’s the future. I mean conventional lights nowadays are very efficient, but I think that they don’t conform really to our style per se. You see that a lot of things are getting flatter, more flexible, and I think that these types of technologies will actually allow houses to have flexible light panels, and maybe even semitransparent light panels that can go over windows and things like that. So those types of technologies will, I think, replace what we see now, for sure.
Glen Paul: Well like I said, it does sound very sci-fi, and this whole house of tomorrow concept is quite amazing. Just when do you think we’ll start to see some of this technology?
Dr Jasieniak: It’s a good question, that one. It’s hard to put a gauge on when these types of technologies will be available, but I think that within the next ten years we’ll actually see emerging prototypes, emerging technologies being released, but I don’t think it’ll probably be until a little bit further than that til we actually see the full capabilities of these technologies.
Glen Paul: OK. Well look, it sounds like a bright future, if you’ll excuse the pun, and thank you very much for talking to me today, Jacek.
Dr Jasieniak: Thank you very much.
Glen Paul: Doctor Jackek Jasieniak from CSIRO Materials Science and Engineering. For more information go to www.csiro.au.