Aperture optimization for emission imaging: effect of a spatially varying background.

A method for optimizing the aperture size in emission imaging is presented that takes into account limitations due to the Poisson nature of the detected radiation stream as well as the conspicuity limitation imposed by a spatially varying background. System assessment is based on the calculated performance of two model observers: the best linear observer, also called the Hotelling observer, and the nonprewhitening matched-filter observer. The tasks are the detection of a Gaussian signal and the discrimination of a single from a double Gaussian signal. When the background is specified, detection is optimized by enlarging the aperture; an inhomogeneous background results in an optimum aperture size matched naturally to the signal. The discrimination task has a finite optimum aperture for a flat background; a nonuniform background drives the optimum toward still-finer resolution.

[1]  R. Shaw,et al.  Evaluating the efficient of imaging processes , 1978 .

[2]  R. F. Wagner,et al.  Efficiency of human visual signal discrimination. , 1981, Science.

[3]  H H Barrett,et al.  Objective assessment of image quality: effects of quantum noise and object variability. , 1990, Journal of the Optical Society of America. A, Optics and image science.

[4]  Harrison H. Barrett,et al.  Hotelling trace criterion as a figure of merit for the optimization of imaging systems , 1986 .

[5]  Kenneth M. Hanson,et al.  Method of evaluating image-recovery algorithms based on task performance , 1990 .

[6]  Sing H. Lee,et al.  Optical Implementation Of The Hotelling Trace Criterion For Image Classification , 1984 .

[7]  R. F. Wagner,et al.  Unified SNR analysis of medical imaging systems , 1985, Physics in medicine and biology.

[8]  H. Hotelling.  The Generalization of Student’s Ratio , 1931 .

[9]  H. Barrett,et al.  Effect of noise correlation on detectability of disk signals in medical imaging. , 1985, Journal of the Optical Society of America. A, Optics and image science.

[10]  J. L. Harris.  Resolving Power and Decision Theory , 1964 .

[11]  H H Barrett,et al.  Hotelling trace criterion and its correlation with human-observer performance. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[12]  C E Metz,et al.  A comparison of optimum detector spatial resolution in nuclear imaging based on statistical theory and on observer performance. , 1978, Physics in medicine and biology.