Abstract: A printed circuit heater and process for forming a printed circuit heater are described. The printed circuit heater is formed by depositing a thin metal layer onto a surface of a metal carrier foil, forming a composite. The thin metal layer has a thickness of about 0.1 &mgr;m to about 2 &mgr;m. The composite is attached to a substrate such that the thin metal layer is in contact with the substrate, forming a laminate. At least a portion of the metal carrier foil is selectively removed from portions of the laminate. The thin metal layer is patterned and etched such that the etched thin metal layer has a heat density of from about 0.5 watts/in2 to about 20 watts/in2 at working voltages from about 3 volts to about 600 volts. The remaining portions of the metal carrier foil, if any, can be selectively removed to thereby provide low resistance busses within the circuit, thus eliminating the need for multiple external connections, and to facilitate evenness of heat distribution.

Abstract: The invention relates to the manufacture of printed circuit boards having improved interlayer adhesion. More particularly, the present invention pertains to adhesiveless printed circuit boards having excellent thermal performance and useful for producing high-density circuits. A metal foil is laminated to an etched surface of a polyimide substrate having a polyimide film thereon. Etching the substrate surface allows for strong adhesion of a pure polyimide film to the substrate.

Abstract: The invention relates to the manufacture of printed circuit boards having improved interlayer adhesion. More particularly, the present invention pertains to adhesiveless printed circuit boards having excellent thermal performance and useful for producing high-density circuits. A metal foil is laminated to an etched surface of a polyimide substrate having a polyimide film thereon. Etching the substrate surface allows for strong adhesion of a pure polyimide film to the substrate.

Abstract: An automatic exposure system for an electronic flash camera incorporates an arrangement for measuring the reflectivity of a scene illuminated by the electronic flash prior to exposure in order to determine certain photographic scene characteristics for use in controlling a subsequent photographic exposure, an arrangement that substantially reduces the complexity and energy consumption of the electronic flash system while improving the ability of the exposure control system to accurately determine these characteristics. The arrangement includes the pre-exposure firing of the electronic flash to illuminate a scene with a pulse of light for a short, fixed period of time. A reflection of this light pulse is integrated for a portion of this fixed period of time. The final integrated value of the reflected light is a measure of subject reflectivity. This integrated value is then employed to derive the desired photographic scene characteristics.