Fluorescence microscope differs significantly from traditional light microscopy (such as brightfield microscope) in several key aspects:  

Contrast Mechanism:

l Traditional Light Microscope: Relies on differences in light absorption and scattering to create contrast. This often results in limited contrast and can make it difficult to visualize specific cellular structures or molecules.

l Fluorescence Microscope: Provides much higher contrast by specifically detecting the emitted fluorescence from labeled molecules. This allows for the visualization of specific targets within a complex biological environment.  

Specificity:

l Traditional Light Microscope: Generally provides a broad view of cellular structures, but lacks the specificity to target and visualize individual molecules or cellular components.

l Fluorescence Microscope: Enables highly specific labeling of target molecules or structures through the use of fluorescent probes (such as fluorescent dyes or proteins). This allows researchers to study the localization, dynamics, and interactions of specific cellular components.  

Image Formation:

l Traditional Light Microscope: Forms an image based on the transmission or reflection of light through the sample.  

l Fluorescence Microscope: Forms an image based on the detection of light emitted by fluorescent molecules within the sample. This emitted light is typically at a longer wavelength than the excitation light, enabling efficient separation of the signal from background noise.  

Applications:

l Traditional Light Microscope: Suitable for general observation of cell morphology, tissue structure, and basic cellular components.

l Fluorescence Microscope: Widely used in a variety of applications, including:

1. Immunofluorescence: Studying the localization of proteins and other molecules within cells and tissues.  

2. Flow Cytometry: Analyzing the properties of cells and particles in suspension.

3. Fluorescence In Situ Hybridization (FISH): Detecting specific DNA or RNA sequences within cells.  

4. Live Cell Imaging: Observing dynamic cellular processes in real-time.