In high-speed sintering, when a thermal lamp starts to scan from one end of a layer, in the first few moments, it irradiates the whole breadth but a fraction of the length of the layer. Thus, the lamp does not scan any area but just a line on the layer. After a few more moments, it covers some more length, and then it has covered some area. It starts from scanning a line, and the line moves in a direction normal to it. The line becomes wider with the progress of scanning, which is an area. This is a linewise scanning. Linewise scanning is fast because it starts from a line. It would not be fast if it had to create a line from scratch by adding many fragments or points. It does not constitute a line by controlling many points, which is reserved for another scanning (pointwise scanning). Besides linewise scanning, pointwise and areawise scanning are given.