Question

Describe an activity to find the least distance to distinct vision​

Answer 1

Answer:

In optometry, the least distance of distinct vision (LDDV) or the reference seeing distance (RSD) is the closest someone with "normal" vision (20/20 vision) can comfortably look at something. In other words, LDDV is the minimum comfortable distance between the naked human eye and a visible object.

Explanation:

Answer 2

Answer:

Hold the text book at certain distance with our hands.

Try to read the content on the page.

Gradually move the books towards eye, till it reaches very close to your eyes.

You may see that printed letters on the page appear blurred or you will feel strain to read.

Now move the book backwards to a position where you can see clear printed

letters without strain.

Ask your friend to measure distance between your eye and text book at this position.

Note down its value.

Repeat this activity with other friends and note down the distances for distinct

vision in each case.

Find the average of all these distances of clear vision.

We notice that to see an object comfortably and distinctly, at a distance about 25 cm from your eyes.

This 25 cm distance is called least distance of distinct vision.

This value varies from person to person and with age.

Explanation: