Inspection apparatus and inspection method

An inspection method, comprising:

• generating collimated light;
• transmitting a first part of the collimated light;
• blocking a second part of the collimated light different from the first part of the collimated light, wherein an image pickup element captures an image of the transmitted first part of the collimated light;
• and
• comparing the image captured by the image pickup element with an ideal image captured by an ideal image pickup element, to inspect the image pickup element.

A non-transitory computer-readable medium having stored thereon computer-executable instructions which, when executed by a computer, cause the computer to execute operations, the operations comprising:

• controlling a collimated-light emitter to generate collimated light;
• controlling a transmission filter to transmit a first part of the collimated light and block a second part of the collimated light different from the first part of the collimated light;
• controlling an image pickup element to capture an image including the first part of the collimated light transmitted by the transmission filter;
• and
• comparing the image captured by the image pickup element with an ideal image captured by an ideal image pickup element, to inspect the image pickup element.