Microscope slides

A microscope slide is a carrier on which small objects are observed microscopically. Today, microscope slides for light microscopy usually consist of a glass plate (also carrier glass) of size 76 × 26 mm (DIN ISO 8037-1). This size was formerly also referred to as the “English format”, in contrast to the “cast format” with the size 48 × 28 mm. The slide thickness is 1-1.5 mm. A distinction is made between slides with cut and ground edges. With the latter, there is less risk of cutting during handling. Slides are also available with and without frosted edges. This can be produced either by etching the glass or by printing and is used for easier labeling of the slide. Some slides are also coated, which provides better adhesion of the objects (e.g. cells or tissue) to the glass. Diagnostic slides are printed on the outside with a colored hydrophobic mask made of Teflon or epoxy, which prevents the droplet from flowing away from the field of view. Simple slides are usually made of soda-lime glass with a refractive index of ne = 1.53 ± 0.02 at λe = 546.07 nm (green Hg line). However, pure white glass, which itself has no fluorescence, is also used for fluorescence microscopy. There are special slides that have one or more round wells to facilitate the examination of liquids. There are also slides with attached chambers for cell culture studies. Furthermore, there are also versions that have a counting comb that can be used to perform frequency counts. For the calibration of lengths under the light microscope, micrometers for microscope slides are offered with a calibrated scale.