The device has an attachment unit for securing an eyepiece in a receptacle (4). A manually activated handle (6) is arranged on an outer side for releasing the attachment unit. The attachment unit is controlled by the eyepiece so as to automatically attach the eyepiece while introducing the eyepiece into the receptacle. The handle is shifted against force applied by a spring in a direction in which the eyepiece is introduced into the receptacle. A spring preloaded control element is movably arranged in the receptacle.