Microscopes with iris diaphragm

Iris diaphragm

— the name comes from the Latin word for the iris of the eye - according to a similar principle, similar devices work. The iris diaphragm consists of a set of petals of a specially selected shape (the so-called lamellae). When moving to close, these petals move from the edges of the working hole to the centre, reducing its diameter; when opening, they move outward, respectively. Iris diaphragms are more complicated and more expensive than disk diaphragms, but they have a number of important advantages over them. First of all, the light transmission in the entire operating range of such devices changes smoothly, which allows you to select the settings as accurately as possible. You can manage the settings without interrupting the observations of the drug; at the same time, iris diaphragms are also as compact and light as possible. As a result, it is this option that is most popular in microscopes of the middle class and above, and is also often found even in simpler models.