| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it possible to discover the abnormality of photomask data in an early time on the design side by a CAD system by converting CAD data and the photomask data to raster data and detecting the difference between both. SOLUTION: The CAD data corresponding to the graphics selected from the graphics stored in an external memory device 12 is converted to the raster data which is displayed by a bit map at a display device 18. Further, the photomask data to be certified is read out of the photomask data stored in the external memory device 12 and is converted to the raster data which is displayed by the bit map on the display device 18. Both pieces of the converted raster data are stored in the prescribed region of a memory device 14. Next, the raster data converting the CAD data stored in the memory device 14 and the raster data converting the photomask data are read out and are subjected to bit map comparison processing. If the difference between both occurs, an error point is displayed at the display device 18.</p> |
