Abstract: A vacuum device includes a negative pressure pump and a vacuum-switching device. The vacuum-switching device includes a cylinder, a piston and a piston-driving device. The cylinder has a first hole row, which includes a plurality of first vacuum suction holes. The cylinder has two through holes at two opposite ends, wherein either one of the two through holes is connected with a negative pressure pump. The piston is slidably connected within a hollow chamber inside the cylinder. The piston-driving device enables the piston to be slid back and forth so as to define two different-pressured chambers, thereby switching the first vacuum suction holes progressively to a different pressure.

Abstract: A calibration plate and a method for calibrating image capturing devices are provided. The calibration plate includes: a plate having a front face and a rear face; a plurality of calibration patterns formed at the front face of the plate, arranged in a regular manner, and used to calibrate image distortions, lens aberrations, and image center positions for the image capturing devices; and a plurality of graphically encoded patterns formed at the front face of the plate, the graphically encoded patterns being different from each other, and the graphically encoded patterns having information providing the positions of the calibration patterns.

Abstract: A calibration plate and a method for calibrating image capturing devices are provided. The calibration plate includes: a plate having a front face and a rear face; a plurality of calibration patterns formed at the front face of the plate, arranged in a regular manner, and used to calibrate image distortions, lens aberrations, and image center positions for the image capturing devices; and a plurality of graphically encoded patterns formed at the front face of the plate, the graphically encoded patterns being different from each other, and the graphically encoded patterns having information providing the positions of the calibration patterns.