Abstract

The expectation-maximization (EM) algorithm based on maximum-likelihood estimation (MLE) has been used for restoring simulated quantum-limited noncoherent imagery in our previous work.¹ Its performance in these computer simulations has motivated us to further test the algorithm on three-dimensional (3-D) real data. In recent experiments, we used an accelerative version of the EM algorithm for this testing.² 3-D optically sectioned images of a fluorescently labeled biological specimen were used in these experiments. These 3-D real data were collected as a stack of 32 128 × 128 images. To reduce the computer execution time and memory space, instead of reconstructing the full 3-D image, we reconstructed a pair of stereo images by applying the slice theorem of computerized tomography (CT). Fig. 1 shows the 17th slice out of the stack of the 32 collected images. This image contains both in focus and out of focus portions. A stereo pair reconstructed by MLE after 100 iterations is shown in Fig. 2.

© 1990 Optical Society of America