Patent · US Expired

Variable accuracy trend graph display apparatus

US4231032A · kind A · utility

7Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 7, 1978
Grant dateOct 28, 1980
Priority date
Expiry dateSep 7, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R13/408
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A graph display apparatus using a CRT display unit of raster scanning type for displaying a graph with a high accuracy, that is, a high resolution. The apparatus comprises a raster counter for counting the number of rasters to identify the raster number of the scanning lines presently scanning the display screen of the CRT display unit, and a plurality of graph display units for displaying a graph with a standard accuracy. Each graph display unit comprises a memory having a capacity corresponding to the number of time points obtained by dividing the time axis extending in the scanning direction of the raster on the display screen by the number n of data plotting for storing the raster numbers corresponding to the levels of the quantities to be displayed at the individual time points, and a comparator comparing the output of the raster counter with the output of the memory read out sequentially in timing relation with the individual time points for providing a coincidence detection signal only when coincidence is reached between the output of the counter and the output of the memory at a time point. The display signal outputs of these graph display units are combined to display a gr…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.