Abstract: The invention relates to a method for sound reproduction and a loudspeaker, in which a vibrating diaphragm controlled by an operating device produces sound in the air surrounding it on the first side, and in which acoustic feedback is prevented by preventing the passage of the air over the edge of the diaphragm to its other side, and in which the air transports the sound to the surrounding free space. The diaphragm is formed as a uniformly vibrating, essentially straight and high element, so that the height H of the diaphragm is at least three times, and preferably at least five times its width W. Preferably, an essentially closed chamber is formed in front of the diaphragm, except for a narrow opening arrangement, in which one or more narrow openings essentially corresponding to the height of the diaphragm permit the passage of air and thus of sound from the enclosure to the free space.

Abstract: The present invention provides a loudspeaker including a case having an inner wall, a front opening, and an edge surrounding the front opening. A diaphragm including a substantially planar front surface, a rear surface, and a periphery is attached to the case with flexible attachment element(s). The attaching means attaches the periphery of the diaphragm to the case in the vicinity of the edge of the front opening. A controller is attached to the case in the vicinity of a central inside portion of the case. An actuator is attached to the diaphragm in the vicinity of a central portion of the diaphragm. The controller and the actuator transform an electric signal provided to the controller into a corresponding vibratory movement of the diaphragm between a high frequency and a low frequency. The diaphragm includes a first area in the vicinity of where the actuator is attached to the diaphragm. The diaphragm also includes a second area between the first area and the periphery of the diaphragm.

Abstract: A headlamp, particularly for vehicles. The headlamp includes a solid piece body formed from a transparent material. The body includes a first, light transmitting surface portion. At least a first and a second opaque mirror surface are disposed on opposite sides of a second surface portion of the body. The first mirror surface is shaped to produce a desired distribution of reflected light on the second mirror surface; the second mirror surface is shaped to produce a desired reflected light distribution in an area illuminated by the headlamp. Light from at least one light source is directed to the first mirror surface, reflected by the first mirror surface to the second mirror surface, and then reflected by the second mirror surface through the light transmitting surface.

Abstract: An acoustic search device comprises an ultrasonic transducer with a plurality of elements for transmitting acoustic signals toward a viewed search area and for receiving echo signals therefrom, a display, an electronic unit and an optical viewing device. The electronic unit controls the transducer and the display which shows a display image of the viewed search area based on the echo signals reflected from the viewed search area. The display image is seen by means of the optical viewing device. The optical viewing device, the display, and the ultrasonic transducer are arranged to form a part of the protective cap of a diver and are situated in a protective cap, substantially in succession in the direction of sight of the diver.