Abstract: A pattern inspection apparatus comprises a sensor data input section for inputting a two-dimensional inspected pattern as image data (sensor data) having a multivalued (non-binary) density distribution, design data input section for inputting reference pattern data (reference data) corresponding to the inspected pattern, a compare section for making a comparison between the image data and the reference data to obtain the difference in density therebeween, a minimum compare section for performing spatial differentiation filtering on the distribution of density between the inspected pattern and the reference pattern in different directions and obtaining the minimum of the absolute values of the filtered outputs, and a first defect determining section for detecting a defect on the basis of the minimum obtained by the compare section.

Abstract: In a method of checking pattern, a pattern of a target is photographed and an image of the check pattern is converted into a check image data which is represented by pixel data and density data. A design data for forming the pattern of the target is also converted into a reference image data corresponding to the check image data. The check and reference image data is processed and converted into check and reference gradient vector data, respectively. The check gradient vector data is compared with the reference gradient vector data in a respective corresponding pheripheral pixel data, and its pheripheral pixel data so that the defect is detected.

Abstract: An electron beam drawing control system has a first memory which stores parameters specifying figures representing a pattern to be drawn in a number of cells. A figure generating device reads out parameters representing each figure sequentially from the first memory and generates dot pattern data corresponding to the figures. A second memory stores dot pattern data generated by the figure generating device. A read control device transforms dot pattern data stored in the second memory into serial form and supplies the serial data to an electro-optical device. The figure generating device includes a plurality of dot pattern converting devices. Also, the dot pattern data for each cell as generated by the dot pattern data converting units are stored in separate cell memories of the second memory.