Abstract: Scanner arrangement which incorporates at least one rotatable unit (15) provided with one or more reflecting facets (16) positioned in the beam path of the scanner arrangement so as to deflect the beam path during a scan. Reflection against the facets takes place within a material (17) having a refractive index greater than 1. The scanning facet against which reflection takes place appears to change from the aspect of the beam path within the material, whereas a transition surface between the material and air appears to be stationary from the aspect of the beam path, or at least moves in space irregularly with movement of the scanning facet.

Abstract: In an optical scanning device in which the active scanning means comprises a rotating polygon provided with a plurality of reflecting facets, the so-called optical invariant ##EQU1## wherein .phi. is the aperture of the scanning device, .alpha. is the field angle of the scan, the NETD is the so-called Noise Equivalent Difference Temperature, is increased by passing the beam path against the polygon so as to be reflected therefrom a multiple of times, and therein with substantially complete tracking of the facets while substantially filling the same completely over the full extension of the facets, with the exception of that facet located nearest the beam detector. This is effected with the aid of stationary beam-deflecting optical means which cause the mutual reproductions between facets with reflection of substantially full extension in the rotary direction of the polygon to take place against diametrically opposed facets at a magnification of approximately -1.

Abstract: A method and an apparatus of obtaining measurement data from a chemical process in a mass in a space, such as the charge in a blast furnace, is disclosed where the mass passes through the space from an inlet to an outlet and chemical and/or mechanical change in the mass takes place as it passes through the process. Sensors implemented as individual, unconnected units are mixed into the mass at the inlet, each sensor being equipped with a transmitter of acoustic or electromagnetic type, and with one or more sensing means connected to the transmitter for sensing the properties to be measured. The transmitter sends signals with information on the properties detected by the sensing means. Reception means for taking up acoustic or electromagnetic signals are placed outside the space with spreadout placing over the defining surface of the space.

Abstract: An arrangement for measuring dimensions and/or checking the dimensional accuracy of large objects (1), such as car bodies or the like. The arrangement comprises a straight movement path (8) and one or a plurality of transmission units (10) movable along the path. During indication of each checking point which may comprise a bolt head, a suspended measuring rod (2-7) or the like, two measuring light beams are projected onto the point concerned from two different directions. When the light beams are projected, two are predetermined and one a variable of the following components: the distance between the starting positions for the first and the second light beam, the angular position between the first light beam and a line drawn between the starting positions and the angular position between the second light beam and said line.

Abstract: A scanning system for optical scanning of a scene in at least one dimension has a multi-faceted reflective scanning rotor as the scanning element. In order to have a high scanning efficiency a so-called facet-tracing is provided such that the beam path is reflected by first and second areas of reflection on the rotor, both areas being disposed in a non-collimated beam path. An optical beam converging means is disposed in the beam path between the scene and the rotor for forming a primary image of the scene between the beam converging means and the rotor. A substantially spherical mirror is disposed in the beam path of the system between the first and the second areas of reflection. A radiation detector is disposed at the end of the beam path. A beam converging optical element, such as a positive lens or a substantially spherical mirror, is disposed in the beam path between the first substantially spherical mirror and the second area of reflection.

Abstract: An arrangement for checking the dimensional accuracy and/or measuring the dimensions of large objects (1), such as car bodies or the like, where the object is provided with checking points such as bolt heads, suspended measuring rods (2-7). At least one movement path is erected beside the object. Provided on each movement path is at least one transmission unit arranged to move along the path which emits a narrow light beam at an angle to the path. At least two light beams are emitted simultaneously from different starting points towards each checking point. In order to make it possible to clearly detect that both light beams impinge on precisely the same point, the light beams are modulated in different phase positions with a modulation frequency which causes the light upon impingement on one point with only one light beam to be interpreted by the eye as flashing. On the other hand, light at the point of impingement is interpreted as steady if light from both light beams impinge on the point.

Abstract: A deflection unit on a path parallel to a light beam has a rider, which grips the track of a measuring guide (not shown) and permits a beam component to pass while deflecting a component. A levelling means is provided on a line bisecting the angle between the incoming and the deflected beams in or parallel to their common plane to facilitate remote positional measurements of reference points on a body in order to make measurements more accurate.

Abstract: This invention relates to a method of registering the tophography and height level of the charged mass in a blast furnace. A distance meter for measurement by means of direct reflection against the surface is placed in the vicinity of the top of the blast furnace, appropriately at an inspection window located there. The distance meter is equipped with an aiming device with which the measuring direction of the distance meter is aimable at selected parts of the surface of the charged mass. A computing unit such as a micro- or minicomputer calculates, on the basis of the siting of the distance meter, the set angles of the aiming device for measurement direction and the results of performed distance measurements, calculates the positions for the different measuring points and presents these in analog or digital form.