Which microscopy technique involves using fluorescence to study specimens?

Fluorescence microscopy is a technique that uses fluorescence to visualize specimens. In this method, specific fluorescent dyes or markers are used to label particular structures within a sample. When exposed to a light source of a specific wavelength, these dyes emit light at a different wavelength, allowing for the clear visualization of the labeled components under a fluorescence microscope. This technique is particularly useful for studying cells and tissues because it enables researchers to highlight specific proteins, organelles, or other cellular structures, making it easier to analyze their distributions and interactions within the sample.

The other microscopy techniques mentioned, such as phase contrast, bright field, and dark field microscopy, do not utilize fluorescence. Phase contrast microscopy enhances contrasts in transparent specimens without staining by using differences in the refractive index, while bright field microscopy relies on transmitted light to illuminate samples and is typically used with stained specimens. Dark field microscopy enhances contrast in unstained samples by only allowing scattered light to enter the objective lens, providing a unique contrast but not involving fluorescence.