Smart sand display

My previous idea was about extending a TFT display by sticking extra ones onto the edges. The problem was with making seamless joints. I've now decided to take it further as a way of solving the problem.
Rather than having merely small rectangular displays, i now propose that each display consist of a single pixel, realised either as a full-spectrum display or as three combined RGB elements, drawing power from some kind of ambient source, possibly provided specially, possibly from the likes of the light in the room, vibrations, static electricity or stray radio waves.
Each pixel is a small device about a hundred microns in diameter. It receives power as described, has a unique identifying number which constitutes an address and picks up a signal which it converts into a particular colour and intensity of light, which is reflected rather than transmitted. It responds to a signal at a particular frequency when it receives a particular number followed by a value describing the light. The initial number is something like thirty-two bits long to avoid interference. It becomes active, changes colour then goes back on standby to conserve power and recharge. It is also "aware" of its nearest neighbours.
When these pixels are close together, they act as a full display, so for example they can be gathered together in a single layer and placed under glass, suspended in a drying liquid and painted on a wall, scattered over a wide area or piled up in a heap.. This means the display is wireless, can be arranged into any shape, including three-dimensional ones, and is possibly able to draw power from its environment.
No more edge problem and a more flexible display.