A-mount

The A-mount is a type of interchangeable lens mount developed by Minolta in 1985 and later adopted by Sony after they acquired Minolta's camera division. It is a bayonet-style mount recognizable by its four metal flanges and a mechanical linkage used for transmitting autofocus drive from the camera body to the lens. The A-mount system was initially designed for autofocus single-lens reflex (SLR) cameras and was maintained when Sony transitioned to single-lens translucent (SLT) cameras.

Key features of the A-mount include:

• Bayonet Mount: A secure and relatively quick method of attaching and detaching lenses.
• Autofocus Drive: The A-mount incorporates a screw-drive autofocus system, where a motor within the camera body physically rotates a screw to drive the lens's focusing mechanism. Later iterations also supported in-lens autofocus motors.
• Compatibility: While Sony discontinued the development of new A-mount cameras in favor of the E-mount, A-mount lenses can often be used on Sony E-mount cameras with the use of an adapter. These adapters may provide varying levels of functionality, including autofocus.
• Legacy System: The A-mount represents a significant part of photographic history, originating with Minolta and continuing with Sony for a period of time. Its discontinuation reflects the industry shift towards mirrorless camera systems.