Brightfield microscopy, or brightfield microscopy, is one of the most basic and simple imaging methods. The principle is to pass/reflect a light beam through/from the sample without changing its properties due to the use of polarizing or other filters. This method of microscopy is applied to stained or naturally pigmented slides with high contrast.
The specimen is illuminated from below and viewed from above - the image of the specimen appears bright, but slightly darker than the background brightness. This method is mainly used for the analysis of fixed stained specimens; it is not very suitable for unstained live cells or tissue sections, as in most cases the light beam passes through the specimens and their structure is not sufficiently defined.