Transparent samples pose serious challenges in bright-field microscopic imaging due to
their low optical contrast, which also affects the imaging speed. While the role of the
substrate in enhancing optical contrast has been investigated for imaging modalities such as
fluorescence, a similar analysis for bright-field imaging has not been conducted. Here, we
explore the effect of the substrate on the optical contrast and imaging speed in bright-field
microscopic imaging. We develop a simulation model to explain the significant improvement …

There are multiple metrics to quantify the contrast in images. These metrics measure
different aspects of the images that are assumed to be the indicators of contrast. Hence, they
perform differently for the features we are interested in. Before comparing the contrast
enhancements by physical methods, we had to identify the proper metric to quantify the
contrast itself.