Abstract: A semiconductor laser diode and method are described, wherein the path of the current through the device between the positive and negative conductors is controlled. Lateral spread of the gain current in the active region is prevented by implanting protons in areas of the active layer flanking a desired gain region. The implanted regions become less conductive, and prevent lateral spread of the gain current. The position of the implanted regions can be selected so that the gain current only crosses a portion of the active layer that supports desired lateral modes of the laser light.

Abstract: A semiconductor laser diode and method are described, wherein the path of the current through the device between the positive and negative conductors is controlled. Lateral spread of the gain current in the active region is prevented by implanting protons in areas of the active layer flanking a desired gain region. The implanted regions become less conductive, and prevent lateral spread of the gain current. The position of the implanted regions can be selected so that the gain current only crosses a portion of the active layer that supports desired lateral modes of the laser light.

Abstract: A semiconductor laser diode and method are described, wherein the path of the current through the device between the positive and negative conductors is controlled. Lateral spread of the gain current in the active region is prevented by implanting protons in areas of the active layer flanking a desired gain region. The implanted regions become less conductive, and prevent lateral spread of the gain current. The position of the implanted regions can be selected so that the gain current only crosses a portion of the active layer that supports desired lateral modes of the laser light.

Abstract: Sandwich-type capacitive electronic discs having thin conductive layers are prepared by adding a thermally processed conductive molding composition comprising a thermoplastic resin, conductive carbon black particles and suitable additives to a suitable solvent to form a dispersion of the conductive carbon black in a solution of the remaining ingredients. The dispersion is filtered to remove impurities larger than a predetermined particle size and coated onto a core disc. The coating is dried to form a conductive layer which is embossed with the desired information.

Abstract: A high density capacitive information disc recording medium fabricated from a conductive plastic molding composition including a moldable plastic and conductive carbon black particles having a volatiles content at 950.degree. C. of less than about 1 percent.