X-ray transmission inspection apparatus and x-ray transmission inspection method

An X-ray transmission inspection apparatus comprising:

• an X-ray source configured to irradiate a sample with X-rays;
• an X-ray sensor installed on a side opposite to the X-ray source relative to the sample and configured to detect transmitted X-rays when X-rays pass through the sample;
• a sample moving mechanism configured to move the sample in a specific transport direction;
• and
• a calculation part configured to calculate a height position of a foreign object in a thickness direction in the sample based on the transmitted X-rays detected by the X-ray sensor,
• wherein a plurality of sets of the X-ray sources paired with the X-ray sensors in one-to-one correspondence are provided,
• each X-ray source of the plurality of sets of the X-ray sources paired with the X-ray sensors in one-to-one correspondence irradiates the sample with X-rays at a different irradiation angle with respect to the thickness direction of the sample, and
• each X-ray sensor of the plurality of sets of the X-ray sources paired with the X-ray sensors in one-to-one correspondence is arranged to detect only the transmitted X-rays of X-rays from a corresponding X-ray source.