This is the near point of the eye. Seeing detail Focusing an image on the retina is only one of the properties of human vision. It will not fire in the dark, or if no light strikes it. The observer will be able to see the image of the object clearly. The image becomes more and more coarse and grainy.
Fine detail becomes harder and harder to make out.
An image consisting of two fine lines drawn 1 cm apart are clearly seen by the eye as two separate lines when viewed from the near point of the average eye. However, if the lines are closer than 0.01 cm, even the best human eye cannot detect if it is looking at one line or two. This ability to detect two closely-spaced objects is called resolving power , and is one of the limits of human vision. Magnifying lenses, therefore, make it possible to see images from objects beneath the resolving power of the unaided eye, and see more detail within those images.