Publications by authors named "Melville Ulmer"

Photodetectors with internal gain are of great interest for imaging applications, since internal gain reduces the effective noise of readout electronics. High-gain photodetectors have been demonstrated, but only individually rather than as a full array in a camera. Consequently, there has been little investigation of the interaction between camera complementary metal oxide semiconductor (CMOS) electronics and the slow response time that high-gain photodetectors often exhibit.

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In this paper wepresent a method to correct the surface profile of an X-ray mirror by using a stress manipulated coating on the back side of mirror shells. The ability to fabricate a thin walled mirror by some replication process is required if future affordable X-ray space missions are to have ~30 times the effective area of the current best X-ray observatory, i.e.

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A method of fabricating replica figured x-ray optics with integral multilayer coatings is presented. With the intact electroforming multilayer process (IEMP) technique, we sputter multilayers onto a reusable superpolished mandrel, electroform nickel over the multilayers, and remove the multilayer-coated nickel shell intact from the mandrel. This approach offers advantages over more traditional, original, and segmented-replica fabrication techniques, including low cost; compatibility with a wide range of mirror designs, diameters, and focal lengths; simple integration with multilayer sputtering processes; and the ability to produce complete shells of revolution.

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