Abstract: An infrared detection device including a matrix of bolometric detectors electrically connected to a reading circuit. Each of the detectors includes at least two electrically conductive thermal insulation structures insulated from one another and fitted in contact at one of their ends with an active zone consisting of a bolometric material. One of the structures is electrically connected at its other end to the reading circuit by a cold electrical connection that is kept at a substantially constant potential. The other structure is electrically connected at its other end to the reading circuit by a hot electrical connection, which is connected in series with a switch integrated into the reading circuit. At least two adjacent bolometric detectors are connected by a common electrical connection to the substantially constant potential of the reading circuit.

Abstract: A bolometric detector including a sensitive part having one or more layers of a sensitive material, the resistivity of which varies with temperature, electrodes isolated from one another, also acting as infrared radiation absorbers, the electrodes being in contact with the sensitive material over at least part of their surface, at least one support region for supporting the sensitive part, acting so as to position the sensitive part, and acting as an electrical conductor, in relation to a read circuit associated with the bolometric detector, and at least one thermal insulation structure electrically and mechanically connecting each support region to the sensitive part. The regions of sensitive material not in contact with the electrodes have at least one corrugation oriented along the direction perpendicular to the plane containing the sensitive part of the bolometric detector.

Abstract: The thread (15) of a wood or the like screw has pairs of V-shaped recesses (22, 23) in the edge of a selected intermediate length of the thread (17). Each pair defines a W-shaped cutout (19, 20, 11). The cutouts (19-21) extend into only a part of radial width of the thread (15). There are only about five cutouts (19-21) at each convolute (17) of the limited length. The lengths of the thread portion (16) at the tip and the thread portion (18) at the head (13) of the screw are devoid of the cutouts. Each cutout defines a cutting tooth (24) which facilitates the driving of the screw into the workpiece. The recesses (22, 23) provide cavities for fibrous debris generated by the respective tooth (24). When the screw is in place, the teeth (24) are pressed axially toward the thread produced in the workpiece to reduce the loosening tendency of the installed screw. The disposition and size of the cutouts (19-21), is about three cutouts per one convolute so as not to unduly impede the torque strength of the screw.

Abstract: In a method and apparatus for regenerating a primary cell, voltage pulses of a predetermined amplitude and a predetermined duration in the range of 10.sup.-3 to 2.times.10.sup.-3 seconds are applied to the primary cell at a frequency of 2 Hz to 200 Hz whereby primary cells which cannot be recharged can be reconditioned for a greatly extended life. The apparatus includes a switching device with a low voltage input connected to a low resistance DC voltage source, an output delivering a sequence of voltage pulses to a primary cell, and a timing generator for timing the switching device.