Near and Far Points

The human eye can focus on objects at different distances to form an image. The eye can focus on any object between the near point and the far point.
The near point, also called the nearest point of distinct vision, is the distance between the eye and the nearest object that can be brought into clear focus without strain or help from glasses or lens. It taken to be 25cm by convention for normal; vision.
The far point is the distance between the eye and the furthest object that can be brought into focus.It is taken to be infinity for normal vision.