Methods for investigating an object by means of a reflectable radiation beam and devices suitable for carrying out the methods having an image sensor rigidly interconnected with an optical detector

A method of investigating an object by means of a reflectable radiation beam which forms a spot on the object which is movable relative to the object, while a portion of the radiation beam reflected by the object is detected by an optical detector, characterized in that the optical detector and a multidimensional image sensor have a common optical axis which is perpendicular to a reference plane through the object, while the positions of the spot on the object projected onto the reference plane are determined from the reflected portion of the radiation beam detected by means of the optical detector during the displacement of the radiation beam over a predetermined track, the desired positions of the spot relative to the object projected onto the reference plane being determined by means of the image sensor, after which differences between the actual and the desired positions of the spot are determined as a measure for differences in distance from the objects to the reference plane along the predetermined track.

A device for investigating an object which device is provided with a radiation source, an optical detector and a displacement device for displacing a spot thrown onto an object by a radiation beam to be emitted by the radiation source, characterized in that the device is further provided with a multidimensional image sensor cooperating with the optical detector and with a positioning circuit for controlling the radiation beam in dependence on the difference between an actual position of the spot detectable by the optical detector and a desired position of the spot detectable by the image sensor.

A device for investigating an object which device is provided with a radiation source, an optical detector and a displacement device for displacing a spot thrown onto an object by a radiation beam to be emitted by the radiation source, characterized in that the device is further provided with a multidimensional image sensor cooperating with the optical detector, the optical detector and the image sensor having a common optical axis which is perpendicular to a reference plane, and is provided with a measuring circuit for determining differences in the distance between the object and the reference plane from differences between actual positions of the spot on the reference plane detectable by the optical detector and desired positions of the spot on the reference plane detectable by the image sensor during the displacement of the radiation beam along a predetermined track.