Work system for substrate, work-sequence-optimizing program, and workbench-quantity-determining program

A system provided with a plurality of arrayed work machines (18, 78, 80, 90), in which a circuit board is conveyed to a downstream work machine from an upstream work machine, wherein the work machine (80) examines small electronic components, and the work machine (90) examines large electronic components. When a small mounting component is to be examined, a detailed examination is preferably performed, but detailed examinations require extra time. Examining large mounting components does not require the same level of detail needed in examining small mounting components. Therefore, the present system allows small mounting components to be reliably examined even if a particular amount of time is required, and allows large mounting components to be examined more extensively than small components. Consequently, examination work can be performed reliably and in less time.