a camera in which the image appears on a ground-glass viewer (focusing screen) after being reflected by a mirror or after passing through a prism or semitransparent glass; in one type (single-lens reflex camera), light passes through the same lens to both the ground glass and the film, while in another type (twin-lens reflex camera), light passes through one lens (viewing lens) to the ground glass and through a second lens (taking lens) to the film, the lenses being mechanically coupled for focusing.
Origin of reflex camera
First recorded in 1925–30
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British Dictionary definitions for reflex camera
a camera in which the image is composed and focused on a large ground-glass viewfinder screen. In a single-lens reflex the light enters through the camera lens and falls on the film when the viewfinder mirror is retracted. In a twin-lens reflex the light enters through a separate lens and is deflected onto the viewfinder screen
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012