US 7,321,458 B2 | ||
Apparatus for controlling the positioning of an optical dithering element | ||
Stephen W. Marshall, Richardson, Tex. (US) | ||
Assigned to Texas Instruments Incorporated, Dallas, Tex. (US) | ||
Filed on Oct. 30, 2006, as Appl. No. 11/554,078. | ||
Application 11/554078 is a division of application No. 10/752982, filed on Jan. 07, 2004, granted, now 7,130,105. | ||
Prior Publication US 2007/0052968 A1, Mar. 08, 2007 | ||
Int. Cl. G02B 26/00 (2006.01) |
U.S. Cl. 359—295 [359/291] | 10 Claims |
1. A system for controlling optical dithering comprising:
an actuator operable to repeatedly position an optical dithering element approximately between first and second positions;
a position sensor operable to sense the position of the optical dithering element at a plurality of sample times, and to generate
a position error indicator signal for each of the plurality of sample times, the position error indicator signal having a
first value responsive to the sensed position exceeding a desired setpoint for the position of the optical element, and having
a second value responsive to the sensed position falling below the desired setpoint; and
a controller, coupled to the position sensor, the controller operable to generate a generally periodic waveform for controlling
the actuator, operable to generate an error signature for a period of the waveform based on a plurality of the position error
indicator signals generated by the position sensor for that period, and operable to modify the waveform for a later period
of the waveform in response to the error signature.
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