As one example of a high density display, consider a field emission display including a phosphor display panel and an array of perhaps thousands of pixelators, each pixelator directed to excite a small region of the display panel. The region excited by one pixelator is called a "pixel" from the contraction of the words picture element. Excitation is generally accomplished by a beam of electrons radiated from a sharp tip structure within the pixelator. Current for the electron beam is supplied to the pixelator as a drive signal from a current source.
The conventional pixelator includes a tip, a current source in series with the tip for providing current for the electron beam, and one or more switches between the source and the tip for enabling the pixelator. In a conventional field emission display, each pixelator can be independently enabled since each has an independent current source. By co-locating the independent current source and the tip, quick pixelator response times are possible because interconnect capacitance between the current source and the tip is minimal.
In addition to quick response time, improved display resolution is highly desirable. Due to the one-to-one spacial relationship between pixelators and displayed pixels, decreased pixel size dictates decreased pixelator size. The size of the conventional pixelator is dominated by the size of the current source made necessary for quick response times.
The difficulties described above with respect to field emission displays find parallels in other display technologies. Conductors used to distribute the drive signal occupy space and so limit the resolution of matrix displays having an array of rows and columns of cells. Matrix display cells include field emission cells, liquid crystal display elements, light modulators, and light emitting cells.
In view of the problems described above and related problems that consequently become apparent to those skilled in the applicable arts, the need remains in high density display technologies for low cost displays of increased resolution. Such displays would find application in laptop computers having monochrome or color displays, image display and monitoring systems, instrumentation, consumer equipment, measurement apparatus, and similar applications including battery powered portable equipment requiring an information or graphic display. Conventional high density displays for these applications are expensive due to factors related to pixelator size and complexity. Complex pixelator design directly increases die size, decreases manufacturing yield, and decreases system reliability.