In a device used to inspect substrates visually, an imaging region and a magnification are specified ahead of time for every component and stored as library data in a memory. The memory also contains CAD data, which include the class of each component on the substrate and its location. During initialization, a control unit links the location data for a component extracted from the CAD data to corresponding library data and specifies a field of view and a magnification for every component on the substrate. Using this data, the control unit creates on the substrate a number of viewing zones to be inspected at various magnifications and stores the data specifying these zones in the memory. When a substrate is to be inspected, the control unit uses the data specifying these zones to control the position and magnification of an imaging unit to collect image data from each zone successively and display them on a monitor.