A dark screening slide is a tool that is used to view slides in a dark environment. There are several synonyms for this term, including dark field slide, screen slide, and dark viewing slide. Each of these terms refers to a similar device that allows the user to view slides in a dark room without disturbing the ambient lighting. Other related terms include darkroom slide, opaque slide, and non-transparent slide. No matter which term is used, these screening slides are an essential tool for any professional or hobbyist who works with slides in a dark environment.