Abstract: A multi-junction solar cell includes a first main surface and a second main surface opposite to the first main surface of a semiconductor body. A topmost pn-junction of a plurality of pn-junctions stacked on top of each other adjoins to the first main surface. A cell edge of the semiconductor body defines a shape of the first and the second main surfaces. An encapsulant on the first main surface provides an environmental protection of the semiconductor body. A mesa groove is provided on the first main surface and penetrates at least the topmost pn-junction. The mesa groove is located adjacent to the cell edge and is created around the circumference of the semiconductor body for providing an inner cell area and a mesa wall, the mesa wall being created between the mesa groove and the cell edge. The mesa groove is filled with the encapsulant.

Abstract: A process detects defects in a semiconductor device, particularly a solar cell or solar cell arrangement, having at least one pn junction in a semiconductor layer of a semiconductor material with an indirect band junction. A voltage is applied to the at least one pn junction to operate it in the transmitting direction; and the radiation behavior of the semiconductor layer generated by the applied voltage, at least for partial ranges of the semiconductor layer, is optically detected and automatically examined for essentially one-dimensional intensity changes in order to detect mechanical defects.

Abstract: A compilation of improvements and modifications to U.S. Pat. No. 5,392,358 which discloses an electrolytic loudspeaker assembly (10) which reproduces a broad band of audio signals. The assembly (10) is comprised of a thin, non-magnetic capacitive transducer (12) which consists of compound diaphragm (14) that is further comprised of a center section (16), a front section (20) and a rear sect compound diaphragm (14) is enclosed by a frame assembly (32). The improvements and modifications to the assembly designs for a center section (16A, 18A); three designs each for a front section (20A, 24A, 28A) and a rear section (22A, 26A, 30A); three designs for a frame assembly (32A, 34A, 36A) and two designs for a transducer driver unit (46, 48). The basic design of the assembly (10) is also augmented by the addition of an acoustic wave diffuser, reflector, and absorbing assembly (40) and an acoustic baffle structure (44).

Abstract: An advanced design for an electrostatic and an electrolytic loudspeaker assembly (10) that comprises a compound diaphragm (12) sandwiched between a first metal stator (40) and a second metal stator (60), wherein each stator includes a multiplicity of perforations (41,61). All the sides of the stators (40,60) as well as the inside surface of the perforations (41,61) are coated with an insulating material (90) also known as ACOUSTAGUARD™ (90) which includes a base coat (92) and a sealing and pigmentation coat (94). The coats (92) and (94) are applied by a unique process that allows ACOUSTAGUARD™ to be applied at room temperature by preferably a spraying technique. The application of ACOUSTAGUARD™ avoids any arcing or corona discharge between the two stators (40,60) which can distort the audio output and damage the loudspeaker assembly (10).

Abstract: A power supply assembly (10) specifically designed to supply a bias voltage to a diaphragm (34) located on an electrolytic or electrostatic speaker(s)(32). The assembly (10) produces the bias voltage from an audio signal derived from an audio amplifier (30). Thus, a direct connection to a utility power source is not required. The assembly (10) is comprised of five major circuits: a rectifier and filter circuit (12) which converts the input audio signal to a regulated d-c current, an adjustable regulator circuit (14) which is applied the regulated d-c current and produces a regulated direct-current voltage, a d-c to a-c inverter circuit (16) which receives the regulated d-c voltage and produces a high voltage a-c, an eight-times multiplier and rectifier circuit (18) which receives the high-voltage a-c and produces a regulated high voltage d-c, and a current limiter circuit (20) which receives the regulated high voltage d-c and produces the bias voltage which biases the diaphragm (34).

Abstract: A compound electrolytic loudspeaker (10) comprising two major elements: a capacitive transducer (12) and a transducer driver unit (116). The capacitive transducer (12) consist of a compound diaphragm (14) that is suspended within a frame assembly (84) and which consists of a front stator (16) having a front stator electrode (32), a rear stator (34) having a rear stator electrode (50), and a center diaphragm (54) having a diaphragm electrode (68). The electrodes interface with the transducer driver unit (116) which receives and amplifies an audio signal applied from a receiver-amplifier (126). The amplified audio signal drives the capacitive transducer (12) in synchrony with the reveived audio.

Abstract: Method and apparatus for producing a non-linear interaction between two electromagnetic waves, e.g. a laser beam and a microwave beam, in a non-linear optical medium, wherein one wave passes through a predetermined region of the medium in a zig-zag path, and the other traverses the predetermined region of the non-linear medium in two opposed directions in such a manner that an interaction-production phase-matching of the two waves is obtained not only in the departing but also in the approaching segments of the zig-zag path.

Abstract: Solid state laser comprising a solid state laser diode for generating fundamental wave laser radiation; an external ring resonator which is arranged in the beam path of the fundamental wave laser radiation and through which the fundamental wave laser radiation passes in a predetermined forward direction; an optical nonlinear medium arranged in the ring resonator for generating the 2nd harmonic of the fundamental wave laser radiation; and an arrangement for feeding fundamental wave laser radiation back to the solid state laser diode which includes a scattering optical element which is arranged in the beam path of the fundamental wave laser radiation of the ring resonator and which causes a small part of the fundamental wave laser radiation to propagate in a direction opposite to the forward direction through the beam path back to the solid state laser diode.