| 摘要 |
<p>Automatic and rapid exposure control is incorporated in a camera having facilities for directing, along a common path, a pair of independent non-coincident light beams from an external object and from a separately illuminable item, such as a data-bearing transparency within the camera. A photoelectric circuit, responsive to the total quantity of the directed light, generates a proportional control voltage for operating an adjustable diaphragm to maintain a predetermined incident level of the directed light on the camera film and/or controlling the item illuminator or an auxiliary illuminator for the external object. Threshold controlled, motor-instrumented apparatus may be additionally provided.</p> |
