The lens is responsible for creating sufficient image quality to enable the vision system to extract the desired information about the object from the image. The lens is critical to machine vision performance because information that is not captured by the lens cannot be re-created in software. In a typical application, the lens is required to locate features within the field of view (FOV), ensure the features are in focus, maximize contrast and avoid perspective distortion. What may be adequate image quality for one application may be insufficient for another. This white paper will explain the fundamentals of using optics to optimize a machine vision application.