Inspection method, computer-readable recording medium, and reference standard plate

A non-transitory computer-readable recording medium recording a program for inspecting a counting function of an imaging system, wherein the program causes a computer of the imaging system to at least perform:

• causing an image sensor of the imaging system to capture an image of a reference standard plate,
• wherein the reference standard plate comprises a base region and a plurality of counting target regions regularly arranged on the base region, the plurality of counting target regions having a phase amount in a thickness direction different from a phase amount of the base region, and
• wherein a known number of counting target regions among the plurality of counting target regions is positioned within a field of view of the image sensor of the imaging system;
• performing a counting function of counting a number of counting target regions included in the image of the reference standard plate;
• performing a comparison of the number of counting target regions included in the image of the reference standard plate and the known number of counting target regions positioned within the field of view of the imaging system;
• and
• determining a reliability of the counting function based on a result of the comparison.