| 摘要 |
The coordinates A X 1/2 and B X 1/2 of respective edges A and B of an object (4) are determined from the half amplitudes A 1/2 and B 1/2 of the highest peaks in the diffractive pattern created by these edges. The half amplitudes A 1/2 and B 1/2 are calculated as half of the difference between these peak amplitudes A max or B max , and the background T. The raw linear dimension of the object (4) is calculated from the difference of the coordinates A X 1/2 and B X 1/2 , and corrected with a set of calibration data, and also corrected for the difference in temperature. Two dimensional profile of the object (4) edges can be obtained. A device for measurement of linear dimension of the measured object comprises a source of radiation (1), the means adjusting and focusing the beam of radiation (2) in the focus zone around the optical axis (6), a photodetector (5), preferably a photodiode or a photomultiplier converting incident radiation into electric signal, and a transport assembly (8) moving the measured object (4) along a path (7) transverse to the optical axis 6 and arranged between the focus zone and the photodetector (5). The transport assembly (8) and the photodetector (5) are coupled to at least one recording and controlling (R&C) device (9) which comprises a memory for storage of pairs of data collected in subsequent moments of time and consisting of the object coordinate along the path (7), and the level of the photodetector signal. The R&C device (9) also comprises a photodetector interface (10) coupled to the photodetector (5), and a positioning interface (11) controlling the position of the support of the measured object (4). The photodetector interface (10) and the positioning interface (11) are coupled to a R&C controller (12) which automates the measuring device, and analyzes and processes mentioned pairs of data and calculates raw and corrected value of linear dimension of the measured object (4). Optionally a display monitor and a printer are coupled to the R&C device (9). |
