Microelectromechanical Systems (MEMS) is a rapidly emerging field of research in which batch fabrication processes are used to construct miniature devices. MEMS devices are particularly well suited to optical applications. Foundry microfabrication offers a substantial cost advantage for prototype system development. In this research, foundry MEMS processes are used to fabricate low-cost deformable mirror systems (MEM-DMs) for adaptive optics. The challenges and design trades associated with fabrication of continuous and segmented deformable mirrors in foundry processes are examined in detail. Micromirror surface figure is shown to be critically important. Beam steering and optical aberration correction experiments conclusively demonstrate the potential of low-cost MEM-DMs. The prototype MEM-DM systems are approximately 1/ 500th the cost of conventionally manufactured deformable mirrors. An innovative direct digital control scheme further reduces adaptive optic system cost by eliminating the digital to analog converter typically required for each controlled element. In addition to the MEM-DMs, other MEMS devices are shown. The thermally actuated piston micromirrors offer greater deflections for operation at longer optical wavelengths. Other MEMS devices examined include a series of tilting mirrors, pressure gauges, test structures, electrostatic scratch drive actuated rotors, and a new type of electrostatic cantilever motor with lateral motion output.
"This major study suggests that prehispanic metallurgy was adopted in western Mexico ca.
Mini Casting Handbook
Principles of metal casting " , Heine , Roper , Rosenthal , TMH ( 1967 ) 6 . " Steel Foundry Practice " , P. Bidulya , Mir Publications ( 1968 ) 7. " Foundry Technology " , P.R. Beeley , Butterworths , UK ( 1972 ) " Fundamentals of ...
Principles of Metal Casting
Metal Casting: A Sand Casting Manual for the Small Foundry
Written in non-technical terms, the sand casting manuals begin by melting aluminium cans over a charcoal fire and end by casting a cylinder head. Volume two (2) coniinues tje sand cassting manual by describing more advanced techinques.
The material contained in this textbook has been gleaned from many technical articles, books and the author's personal notes, taken while teaching at the Cast Metal Institute.
Foundry Work: A View of the Industry