Abstract: Device measures external and internal dimensions of measurement objects using a light source for illuminating a slit diaphragm, in front of or behind which a spirally slotted disc is arranged, slit diaphragm and disc being rotatable in relation to each other and the disc having a spiral slot intersecting the slit of the slit diaphragm, the interaction of which with the slit creates a hole aperture. Evaluation device measures the time in which the light beams scan the measurement object and determines dimensions from the measured times. To scan the measurement object simultaneously in different spacial planes or in one plane in different axes, several slits are provided in the slit diaphragm. Slits may be disposed radially around axis of rotation. Light source(s) may emit light of one or more wavelengths or different frequency modulated light amplitudes.

Abstract: Device measures external and internal dimensions of measurement objects using a light source for illuminating a slit diaphragm, in front of or behind which a spirally slotted disc is arranged, slit diaphragm and disc being rotatable in relation to each other and the disc having a spiral slot intersecting the slit of the slit diaphragm, the interaction of which with the slit creates a hole aperture. Evaluation device measures the time in which the light beams scan the measurement object and determines dimensions from the measured times. To scan the measurement object simultaneously in different spacial planes or in one plane in different axes, several slits are provided in the slit diaphragm. Slits may be disposed radially around axis of rotation. Light source(s) may emit light of one or more wavelengths or different frequency modulated light amplitudes.