method of measurement to determine diameters of draehten or profiles or by diffraction of light rays and rundkoerpern institution for the implementation of the procedure.

摘要

The method comprises generating from a monochromatic light source a field of non coherent light rays presenting a homogenous spatial distribution of light energy, placing the element to be measured within said field by maintaining it in a fixed position while allowing it to deviate from its initial position only in parallel to itself, propulsing said rays to a sensor arranged perpendicularly to the axis of said light rays, masking the central area receiving the maximum energy flux, converting the diffraction fringe images situated on either side of said central area into electric signals after having calibrated said sensor and, analyzing the signals which are function of the distribution of light energy. The device for implementing such method comprises: a monochromatic light source (S); a diaphragm (M2) with an orifice having a microscopic size and situated on the path of rays emitted by the source and in the optical axis; an optics having a given focal length (L2); a sensor (C); a mask (M3); an analyzer, calculator converter system (C1-C2).