VELOCITY-MEASUREMENT USING PHASE ORTHOGONAL SPATIAL FILTERS

An optical pattern on an object's surface is converted into a componen t of a specific spatial frequency through a spatial filter, and the mo vement or the velocity of the object can be estimated from the spatial frequency. An error of the velocity measurement based on conventional spatial filter method is large in case of low-speed measurement. The authors develop a velocity measurement system based on a new spatial f ilter method that can compensate the error. This paper presents the sy stem configuration and the compensating method.