FINSIG 05

FINSIG 2005Kuopio, FinlandNotations Usually the 2D image plane is discretized with N2square pixels and measurement operator, denotedas H, that is the mapping from discretized activitydistribution θ to the projection p, PSfrag is constructed. replacements Construction of observation matrix H may include,for example the effects of geometry, attenuation,scatter and septal penetration in the collimator. Mapping is different for each measurement direction.In the following we will denote the observationmatrix at time t with H t and the correspondingobserved projection vector with p t . Thus t denotesboth time and direction of the camera head.zyxθ 1θ N 2θ Np t1pt2Mikko Kervinen, Department of Applied Physics, University of Kuopio Slide 6