Abstract: A movie camera is shown with a zoom lens capable of automatic focus by movement of the lens system closest to the camera body instead of the front objective. As a result the system is more efficient because the heavy large front objective is fixed during automatic focusing and the focusing system need only move a smaller lens or group of lenses which are closer to the camera body. The variator, the compensator, the fourth lens group or any combination of them can be adjusted for automatic focusing.

Abstract: Disclosed is a reflex rangefinder system for a camera having a pair of li reflecting members mounted to reflect light rays from the scene in the viewfinder system. The members are dichroically coated with different complementary colors such that the dual image formed when the objective lens is out of focus have different colors to enhance the distinction for easy focusing.

Abstract: The present invention relates to a device to adjust the position of optics lens systems which are movable relative to each other, and is characterized in that the device is equipped with a plural number of cam grooves variable relative to each other to adjust the position, frames to support the optical elements composing said optic lens system and springs forcing said frames to always be engaged in said adjusting cam grooves, whereby the forcing springs present forcing forces to compensate the components along the directions to move said adjusting cam grooves of the forces given to said plural number of said adjusting cam grooves.

Abstract: Attention has been directed to the fact that in zoom objective lens systems, the compensator for compensating the focal point shift caused by the zoom movement of the variator has generally two solution curves. A novel zooming mechanism such that the compensator is transferred from one to the other solution curve in the middle position of the zooming is employed in a zoom lens system to which this invention relates. As a result, this permits the variator and compensator to partake equally the function on magnification variation to enable minimizing the image shift sensitivity of each movable lens group and making the diameter of the front lens element small, and moreover compensating the variation of aberrations to very good degree.