This guide provides extensive coverage of microscopy imaging principles. After reviewing the main principles of image formation, diffraction, interference, and polarization used in microscopy, this guide describes the most widely applied microscope configurations and applications. It also covers major system components, including light sources, illumination layouts, microscope optics, and image detection electronics.

This guide also provides a comprehensive overview of microscopy techniques, including bright field and dark field imaging, contrast enhancement methods (such as phase and amplitude contrast), DIC, polarization, and fluorescence microscopy. In addition, it describes scanning techniques (such as confocal and multiphoton imaging points); new trends in super-resolution methods (such as 4Pi microscopy, STED, STORM, and structured illumination); and array microscopy, CARS, and SPIM.

In the 17th century Robert Hooke developed a compound microscope, launching a wonderful journey. The impact of his invention was immediate; in the same century microscopy gave name to "cells" and imaged living bacteria. Since then microscopy has been the witness and subject of numerous scientific discoveries, serving as a constant companion in humans' quest to understand life and the world at the small end of the universe's scale.

Microscopy is one of the most exciting fields in optics, as its variety applies principles of interference, diffraction, and polarization. It persists in pushing the boundaries of imaging limits. For example, life sciences in need of nanometer resolution recently broke the diffraction limit. These new super-resolution techniques helped name microscopy the method of the year by Nature Methods in 2008.

Microscopy will critically change over the next few decades. Historically, microscopy was designed for visual imaging; however, enormous recent progress (in detectors, light sources, actuators, etc.) allows the easing of visual constrains, providing new opportunities. I am excited to witness microscopy's path toward both integrated, digital systems and nanoscopy.

This Field Guide has three major aims: (1) to give a brief overview of concepts used in microscopy; (2) to present major microscopy principles and implementations; and (3) to point to some recent microscopy trends. While many presented topics deserve a much broader description, the hope is that this Field Guide will be a useful reference in everyday microscopy work and a starting point for further study.

I would like to express my special thanks to my colleague here at Rice University, Mark Pierce, for his crucial advice throughout the writing process and his tremendous help in acquiring microscopy images.

This Field Guide is dedicated to my family: my wife, Dorota, and my daughters, Antonina and Karolina.

Tomasz Tkaczyk

Rice University