| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately detect light from an object to be inspected, even in an environment where the level of the quantity of background light is high, or in an environment where light from the object to be inspected is weak. SOLUTION: The object to be inspected is irradiated with pulse light which is turned on and off at a predetermined frequency, and an area containing the irradiated object to be inspected is imaged. A plurality of reference signals including signals of a plurality of frequencies being integer≥1 times the predetermined frequency are generated, and by using the generated plurality of reference signals, imaged signals are detected synchronously. A plurality of detection signals detected synchronously are added, and based on the added synchronous detection signal a measurement signal whose noise component has been removed is output. COPYRIGHT: (C)2009,JPO&INPIT |
