A trinocular microscope may be an optical, acoustic, or an electron microscope. In other words, it may be a microscope in which the specimen is illuminated by visible light, by sound, or by a particle beam of electrons. In addition, the third eyepiece may have been added to a binocular compound microscope or a stereo microscope. A binocular compound microscope uses one lens array for the objective but has a pair of eyepieces, with the light from the image formed by the objective split by a prism. A stereo microscope has two eyepieces, but also two objectives as well, so that the examiner’s view appears three-dimensional. In either case, the user taking advantage of the third lens on one of these two types of trinocular microscope will be provided with a monocular view. A trinocular microscope may have one of several purposes. One purpose is to allow a second viewer access to a specimen at the same time as the person who is mainly using the microscope. This means that an instructor can, for example, look at what a student is seeing to answer a question or to check the accuracy of the student’s observations. In addition, the instructor can invite a student to share his or her view of an interesting specimen or when modelling how to adjust the focus, for example. This extends the instructional possibilities from the situation in which one person must not be viewed in order for the other person to have a view. Another purpose of a trinocular microscope is to allow the use of technology to either preserve the images seen through the microscope by recording them or projecting them.