
Ink-on-paper flashlight rolls up to produce light
The design by Akihiro Tashida of Nendo uses a silver conducting ink on YUPO paper made by Takeo that is used in ballot paper for elections. This was chosen as the ink sits evenly and the smooth surface ensures the ink and paper can be rounded with minimal force, and are less likely to curl. The paper is also hard-wearing, water resistant and therefore also suitable for industrial applications.
The circuits on both sides of the paper were printed with a checker pattern, and two button cells and seven LEDs were glued on with conductive adhesive. The resistance was changed by varying the path length of each LED by adjusting how tightly the paper is rolled, enabling the lighting to be controlled.

As the LEDs change colour while touching the paper, if the LEDs are on the inside the light is a warm orange colour. If the paper is rolled the other way, the light turns white.
Nendo points to many different possible applications, such as emergency use and disaster prevention as the rolled torch can be placed in a ring as a desklamp or main light.
