To provide a hole image pickup device for obtaining an image having a high contrast between an object and an object hole independently of an image pickup condition.

A plate body 28 is irradiated with the lighting light having radiation optical axes C28a and C28b inclined against an image pickup optical axis C27 of a camera 27 by luminaires 28a and 28b to pickup an image of the plate 21 with the camera 27. The image thereby picked up has a high lightness in an image part of the plate body 21 and a low lightness in an image part of a through hole 22 even if the image pickup condition such as an angle of the image pickup axis C27 in relation to the plate body 21 is changed, and has the high contrast having a large difference of lightness between both the parts. The through hole 22 can be easily and securely detected on the basis of the obtained image.

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