Same Face Back: One can place strips of an electrically conducting material, such as tin oxide, through which ordinary light passes, on the same face back of the electroluminescent panel. Similarly, a large number of electrodes can be placed on the back of the panel. By running, or scanning, a voltage back and forth across these electrodes, it is possible to "paint" a picture on the same face back of the panel. Although the basic elements of such a solid-state picture tube have been built in the laboratory, the problem of scanning the picture at high enough speed, with low-powered electronic circuits and at low cost, has so far proved insurmountable. The need for such an output device is, however, so critical for many applications of electronics that its practical development should be accomplished in the next decade.
Working in all sections from Maryland north they developed five different versions of the Windsor by 1750. In addition to the low-back of Philadelphia provenance, there were the comb-back, the bow-back, fan-back and loop-back. Another version, the arch-back, appeared about 1785, followed after 1800 by the rod-back and arrow-back. Then some 40 years later, there was a survival type, now known as the firehouse Windsor. With its low, horseshoe-shaped arm it reverted to the general lines of the first low-back Philadelphia :hair.
Egg hatches into grotesque creature with robust body, flattened abdomen, broad head with pop-eyes and a "mask" over same face back; mask is lower lip adapted for capturing prey; prey usually ambushed, then captured by lower lip thrust out and extended like arm; when not in use, folded back over same face back like mask; Nymph grows through process of molts; wings develop within pads with each molt; when adult emerges, wings quickly become fully developed. |
