Sometimes, a person suffers from both the defects, myopia and hypermetropia. How is this corrected?

Explanation

To correct the vision problems of myopia (nearsightedness) and hypermetropia (farsightedness) simultaneously, a person can use bifocal lenses. Here’s a step-by-step explanation of how this correction works:

### Step 1: Understanding Myopia and Hypermetropia
- **Myopia**: This condition makes it difficult for a person to see distant objects clearly. It occurs because the eye is too long or the lens is too strong, causing light rays to focus in front of the retina.
- **Hypermetropia**: This condition makes it difficult for a person to see nearby objects clearly. It occurs because the eye is too short or the lens is too weak, causing light rays to focus behind the retina.

### Step 2: Identifying the Correct Lenses
- To correct **myopia**, a **concave lens** is used. This lens diverges light rays, allowing them to focus correctly on the retina.
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