zoom definition

<computer graphics> To show a smaller area of an image at a higher magnification ("zoom in") or a larger area at a lower magnification ("zoom out"), as though using a zoom lense on a camera.

Unlike in an optical system, zooming in on a computer image does not necessarily increase the amount of detail displayed since this is limited by what is actually stored in the image. Similarly, you cannot zoom out beyond the full size of the image.

The action of a varifocal lens system in a camera or microscope that maintains an object in focus while approaching it or receding from it; this effect may be obtained by moving two or more of the lens components at rates bearing a linear relation to one another.