Figure 1: (a) PortaChrome is a flexible contact light source that can reprogram the appearance of an object previously coated with photochromic material. PortaChrome has integrated UV and RGB LEDs that saturate and desaturate the color channels of photochromic material. PortaChrome is portable and flexible, allowing it to be attached to (b) a backpack to reprogram the back of clothes, (c) the inside of a sleeve to reprogram a splint brace, (d) a wireless charger to reprogram the back of a device, and (e) the inside of a headphone case to reprogram the design of a headphone.
In this paper, we present PortaChrome, a portable light source that can be attached to everyday objects to reprogram the color and texture of surfaces that come in contact with them. When PortaChrome makes contact with objects previously coated with photochromic dye, the UV and RGB LEDs inside PortaChrome create multicolor textures on the objects. In contrast to prior work, which used projectors for the color change, PortaChrome has a thin and flexible form factor, which allows the color change process to be integrated into everyday user interaction. Because of the close distance between the light source and the photochromic object, PortaChrome creates color textures in less than 4 minutes on average, which is 8 times faster than prior work. We demonstrate PortaChrome with four application examples, including data visualizations on textiles and dynamic designs on wearables.
An important step towards achieving the vision of "The Ultimate Display" is to augment the surfaces of objects with display capabilities, such as changing their color and visual texture, through novel display fabrication methods (DisplayFab). This capability has initiated new application opportunities, allowing users to fit multiple designs on personal items such as phone cases and shoes and to display relevant information in the daily environment, such as showing a calendar on a mug.