The disclosure describes a system for measuring three-dimensional coordinates comprising a position detector which detects orthogonal coordinate positions of X-, Y-, and Z-axes on a surface to be measured; a noncontact-type displacement measuring instrument which moves along the surface to be measured; a device which controls the attitude of the displacement measuring instrument; a coordinate operation processor which converts the data from said position detecting means, from said noncontact-type displacement measuring instrument, and from said device into three-dimensional coordinates of the surface to be measured; a computer which files and transfers to an external unit the data that are operated by said coordinate operation processor; and a singular point determination processor which introduces the coordinate data from said coordinate operation processor, which extracts any singular points, and which transfers the coordinates thereof to said computer.

A method of rapidly determining surface relief of an object or a structure without making contact therewith based on quantifying the degree to which the image of an illuminated point or small spot on the surface is defocussed. Said point or spot is illuminated by a source of electromagnetic radiation such as a laser, and the relief is determined in the form of a profile where the height of any point on the profile is represented by the ratio of the energy values of two beams derived by splitting a single beam reflected from the surface under investigation: one of the beams acting as a reference and the other of the beams being limited by the action of a diaphragm and constituting a measurement beam.

A method and an apparatus for dimensional measuring of objects of any form and depth. The apparatus comprises at least an illumination system (1) having an optical filter (4), a manipulator unit (5, 6), and an observation system having an optical filter (9). The optical filters (4, 9) are designed so that most of the light passing the object and not being influenced by the object is stopped. The manipulator unit is such that between measurements either the object is made to rotate about one or more fixed rotation centers or to follow one or more known rotation paths, or the whole or parts of the observation optics are made to carry out a coupled movement or alteration in accordance with the whole or parts of the illumination optics, such that the illumination means and the observation means are completely or partly locked together and are altered relative to the object.

In order to make possible a high-speed measurement of the surface structure of a sample of any shape or any weight and also to make feasible a direct observation of the surface portion requiring measurement, the surface structure measuring apparatus comprises: a laser light beam source; an objective lens collecting the laser light beam emitting from the light source onto the surface of the sample; a pair of light deflectors disposed at positions conjugate with the pupil of the objective lens, respectively, to perform two-dimensional scanning of the surface of the sample by altering the incidence angle of the laser light beam impinging onto the objective lens; an observation optical system incorporated between the objective lens and the light deflectors for the observation of the surface of the sample; focus detecting device receiving the light reflected at the surface of the sample for detecting a displacement of the surface portion of the sample requiring measurement from a predetermined focal position; and image processing and indicating device for indicating the structure of the measured surface of the sample based on the output delivered from the focus detecting device.

This invention enables examination of semi-conductor chips either on a planar basis or on a three-dimensional basis to determine the characteristics of the chips. Laser light is passed through a first pinhole and is focussed on a wafer. The light reflected from the wafer is passed through a second pinhole and is focussed on a photomultiplier. The focal length between the first pinhole and the wafer is the same as the focal length between the second pinhole and the multiplier. This arrangement provides for a high signal-to-noise ratio to be produced and image information data to be provided within minimal time lags such as a small fraction of a second. An electrically controllable active mirror operable within the beam-shaping optics of the scanning field may be included to displace the plane of the examination field. This active mirror may be controlled to assume the shape of different types of mirrors including a planar mirror. By controlling the operation of the active mirror, the etchings of first materials on the wafer and the depositions of other materials on the wafer may be examined at different depths. The control of the active mirror may be provided at a different frequency than the frequency of the light providing for the examination of the wafer. The visual portion of the light spectrum from the laser may be further processed to determine such parameters in the wafer as the distribution of photoresist residues on the wafer.