[54] BEAM SCANNING GALVANOMETER WITH LOW INERTIA MIRROR AND MAGNET
[75] Inventors: Jasper S. Chandler, David M. Orlicki, both of Rochester; John M. Kresock, Elba, all of N.Y.
[73] Assignee: Eastman Kodak Company,
Rochester, N.Y.
[21] Appl. No.: 723,368
[22] Filed: Jun. 28,1991
[51] Int.Cl.5 H04N1/21
[52] U.S. CI 346/109
[58] Field of Search 346/108, 76 L, 107 R,
346/160, 109; 359/197, 198, 199, 223, 225, 872
[56] References Cited
U.S. PATENT DOCUMENTS
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5,177,631 1/1993 Orlicki et al 359/214
Primary Examiner—Mark J. Reinhart
A beam scanning galvanometer is disclosed which oscillates a mirror in a non-resonant mode. The moving parts of the galvanometer are made with as small a moment of inertia as possible because the mirror is oscillated in a non-resonant mode. The galvanometer uses two sets of crossed leaf-springs to support the mirror instead of bearings which are usually used in non-resonant galvanometers. Each of the sets of leaf-springs is formed of a single strip of cold rolled stainless steel. The springs are embedded in uniquely shaped cavities in a permanent magnet that supports the mirror at a distance very close to an axis of rotation of the mirror. The mirror is specially shaped with beveled edges so that its moment of inertia is low and so that it can oscillate in very close proximity to a driving current coil which surrounds the mirror supporting magnet. A magnetic position sensor is used to detect an angular position of the mirror during operation of the galvanometer. A compensating system eliminates distorting magnetic field effects from a magnetic driving system from adversely influencing the magnetic position sensor. Signals from the magnetic position sensor are usable to provide accurate feedback information to a galvanometer driving system.
12 Claims, 12 Drawing Sheets
