The near point

The idea

The near point, or least distance of distinct vision, is the minimum distance at which objects are seen most distinctly without strain; for a young adult with normal vision it is about 25 cm.

How close can you read?

Hold a printed page far away, then bring it slowly closer to your eyes. At first you can read it. Later the letters blur and your eyes strain.

Roughly how far is the page from the eyes of a young adult with normal vision at the closest comfortable distance?

• About 25 cm
• About 2.5 cm
• About 250 cm

Three distances

Open every tab.

The closest clear distance

There is a closest distance at which the eye can see an object clearly and comfortably. We call it the near point. For a young adult with normal vision it is about 25 cm.

The near point, or least distance of distinct vision, is the minimum distance at which objects are seen most distinctly without strain; for a young adult with normal vision it is about 25 cm.

Notes

The near point (least distance of distinct vision) is the minimum distance for distinct vision without strain: about 25 cm for a young adult with normal vision.

Check yourself

For a young adult with normal vision, the near point is about how many centimetres from the eye?

Answer: 25 cm

For a young adult with normal vision, the near point is about 25 cm.

What is another name for the near point of the eye?

The near point is the minimum distance at which objects can be seen…

A page is held much closer than the near point. What do we expect?

• The far point of the eye. The far point is the farthest point up to which the eye can see objects clearly.
• The power of accommodation. The power of accommodation is the ability of the eye lens to adjust its focal length. It is not a distance.
• The least distance of distinct vision — correct. Yes!
• most distinctly without strain — correct. Yes!
• at all, even if they look blurred. The near point is the minimum distance for seeing most distinctly without strain.
• with the pupil fully closed. The near point is about distinct vision without strain. It is not about the pupil.
• The page is seen most distinctly without strain. That is true only at or beyond the near point.
• The page may look blurred, or the eye may feel strain — correct. Yes!
• The page looks the same as at 25 cm. Closer than the near point the focal length of the eye lens cannot decrease enough, so the image may be blurred.