Figure 2. Electrolumine scent panels silk-screened onto flexible fabric on the Puddlejumper raincoat light up in response to rain.

the other examples we’ve outlined here, even the relatively limited behavior of such a system can be parlayed into a sophisticated multichannel output device through creativity of process and craft.

tion techniques are also applicable to standard ( end-emitting) fibers, resulting in small points of light rather than glowing lines or strands.

Discrete light-emitting diode (LED) lights are also used to create active surface topologies. Although LEDs are not inherently flexible, their small manufacturable size and simple circuitry means they can be dispersed over a flexible substrate. ColorKinetics, Inc. ( www.colorkinetics.com) and Element Labs ( www.elementlabs.com) offer products that incorporate LEDs into collapsible bendable matrix configurations and flexible strands. Others embed matrices of LEDs in flexible substrates that can be curved, formed to a surface, and even used as a wearable material. Lumalive technology from Philips Research ( www.lumalive.com/ business/) features fabrics and clothes embedded with LED matrix displays constructed in this fashion.

Innovative display interfaces are not limited to light-emitting sources. Alternative active materials (such as thermochromic inks that change color with temperature) can be used to construct novel display surfaces. A number of artists and designers, including International Fashion Machines ( ifma-chines.com) and XS Labs ( www.xslabs.net), have used these inks as overprints on top of textiles that incorporate conductive spun threads. When a current is applied to the textile, resistive heating activates the printed ink and initiates a color change. Heating and cooling the metal filament manipulates the color of the textile-display over time [ 1]. As with

CONCLUSION

The practical application of flexible displays to particular user scenarios appears to be strongest in the fields of product, military, and fashion design. Flexibility or perhaps elasticity is inherently desirable for anything worn on the body. The tactile properties of soft and malleable surfaces also make sense in myriad design and interactive environments. What is interesting about the general domain of nonrigid displays is that so many aspects of design and engineering converge to generate displays that are also materials. From them we can imagine displays that curve to fit any space or form, flex to accommodate motion, and deform in response to physical interaction. Rollable or foldable displays for portable devices, large-scale interactive surfaces, and textiles with integrated displays in turn permit the design of user interfaces that are physically, as well as conceptually, flexible. c

REFERENCES

1. Berzowska, J. and Bromley, M. Soft computation through conductive textiles. In Proceedings of the International Foundation of Fashion Technology Institutes Conference (Toronto, Apr. 12– 15, 2007).

2. Lieberman, D. Divergence of e-paper displays. EETimes (Dec. 3, 2007).

ELISE CO ( elise@aeolab.com) is a media artist and founding partner of Aeolab, a design and technology consulting firm in Los Angeles. NIKITA PASHENKOV ( nik@aeolab.com) is a co-founder of Aeolab, a design and technology firm in Los Angeles.

© 2008 ACM 0001-0782/08/0600 $5.00