At the Sign & Display Show 2008 in Tokyo (that ends tomorrow), a company called Teraokaseiko [JP] is exhibiting a transparent touch display, based on an inorganic electroluminescent panel, that can be operated by touching either side of the display.
Teraokaseiko’s self-developed orange-colored monochrome panel features a resolution of 256 × 120. While the display has a transmittance of 51.2%, light transmittance of the inorganic EL panel (and the two touch panels attached to both of its sides) stands at 80%.
Further technical information is rather scarce at this point but the concept itself is quite cool. The new touchscreen can be used for digital maps (users will not hide parts of the display with their hands) and for two-player games, for example.