And we thought projectors were getting small when they were the size of
a Mac mini! Light Blue Optics has created a micromini projector that’s
the size of—wait for it—a matchbox, and it’s going to be used with a cellphone.
Light Blue Optics has developed ground-breaking laser projection technology, which will power a new generation of pocket-sized digital video projectors. The company is based in Cambridge, UK.
Digital video projectors that produce large, high quality images are becoming increasingly popular, but there are limitations in the technology that make miniaturization very difficult, preventing projectors from making inroads into the potentially lucrative mobile device markets.
Laser projection using computer-generated holograms (CGHs) represents a compelling alternative to conventional image projection. Video projectors based on this CGH technology are efficient and require only a very few components, which
means they can be made very small – and the smaller the CGH, the bigger the image that results. So a tiny projector producing large images could, for the first time, be integrated into a laptop, a PDA, or even a mobile phone.
Light Blue Optics is currently developing links with a number of industrial partners. They welcome contact from companies potentially interested in integrating their technology with their products.
Why hasn’t this been done before?
The concept of a holographic projector is not new, but up until now technical issues have prevented development of an actual product based on this technology.
- Holograms are extremely complex objects mathematically, and calculating them fast enough for video applications is very difficult; even the most powerful computers would take minutes to generate a hologram to project just a single video frame.
- The projected images produced by holograms tend to be speckly and of very low quality.
- The lasers that are required to illuminate the holograms have, until very recently, been very expensive and limited in availability.
In the Photonics and Sensors Group at the Cambridge University Engineering Department, several major breakthroughs have been made, together making possible the generation and display of high quality holograms at video frame rates, using just a single custom chip that we have designed.
Light Blue Optics has been set up as a spin-out company in order to commercialise this ground-breaking research through exploitation and development of thier strong IP portfolio.
How does it work?
A hologram pattern, which to the naked eye looks like a collection of
random dots, is displayed on a small liquid-crystal-on-silicon
(LCOS) microdisplay – a tiny, very fast liquid crystal display built on
top of a chip. The hologram patterns are calculated by Light Blue Optics’
proprietary ‘hologram chip’ so that when the microdisplay is
illuminated by laser light, the light interferes with itself in a complex
manner through the physical process of diffraction which, when
carefully controlled, results in the formation of a large, high quality
projected image on, for example, a screen or a wall.
Unlike a conventional video projector, heavy, bulky lenses
are not required: diffraction does all the work for you, and the projected
image is sharp and in focus at any distance.
What will this lead to?
There are a huge number of applications for this technology
in fields including business, home entertainment,
aerospace and advertising. At present, the focus is on 2D
applications, in particular tiny personal projectors for business and
home use. The illustration shows an artist’s impression of a potential early
product: a personal video projector, which you could download
movies to and then play anywhere, using a wall as the screen.
In the future, the same technology could be extended into 3D
applications – while we’re some way away yet, our technology could bring the holographic video displays of science fiction one step closer to reality.
When will products be in the shops?
At present, Light Blue Optics has a lab-based
demonstrator, which converts a standard composite video signal
into high-quality 2D holographic video, in real time. The hologram generation engine runs in a commercially available FPGA (field-programmable gate array) chip, whose design extends naturally to cheap mass production.
Other processing platforms including low-power digital signal processing (DSP) ICs are also under development.
Light Blue Optics is working with several strategic partners to further develop this technology into real products. It is envisaged that devices based on this technology will be in the shops in the next two to four years.