Infrared scanner

US5869945A · kind A · utility

Assignee

• Raytheon TI Systems, Inc. · US

Inventors

• Humphrey W. Ha · Plano, US
• Mark Gohlke · Plano, US
• Mark G. Webb · Dallas, US
• Keith R. Kuemmerle · Richardson, US
• Michael R. Thering · Austin, US
• Steven Alex Jenkins · Plano, US
• Gary R. Herrington · Plano, US

Key dates

• Filing date: Jan 10, 1997
• Grant date: Feb 9, 1999
• Expiry date: Jan 10, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B13/024
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A scanner which includes a motor for driving a load and circuitry for providing a position error signal responsive to the difference between a predicted position of the load and the actual position of the load, preferably a mirror scanning a scene. The motor is driven in response to the position error signal. The position error signal is provided plural times during a single scanning of the scene. The circuitry for providing a position error signal includes a closed loop filter system for filtering the error signal to provide a filtered error signal, an adaptive filter system for operating on the filtered error signal to provide an adaptively filtered error signal and summing circuitry for summing signals indicative of the predicted position, the filtered error signal and the adaptively filtered error signal. The closed loop filter system includes, in series, at least one first order lead lag filter and a double integral plus proportional filter. The adaptive filter system includes, in series, a low pass filter, a register and an integrator.