What is fusion in the context of vision?

Fusion in the context of vision refers to the ability of the eyes to coordinate and work together to focus on a single object, creating a unified visual perception. This process involves the brain combining the slightly different images received from each eye to create a single image, allowing for depth perception and a full field of view.

When the eyes are properly aligned and functioning well, they can effectively fuse images, making it possible for a person to perceive depth and the spatial relationship of objects in their environment. This is a crucial aspect of binocular vision, enabling complex visual tasks such as reading or driving.

The other options, while related to visual function, do not accurately define fusion. Distinguishing colors pertains to color vision, adjusting focus is about accommodation, and seeing three-dimensional depth is a result of fusion rather than a definition of it. Fusion specifically highlights the capacity to merge the visual inputs from both eyes into a coherent image.