Eyeglasses

Eyeglasses, also known as spectacles or glasses, are optical devices consisting of lenses mounted in a frame that holds them in front of a person's eyes. They are primarily used to correct vision, but can also be used for protection and fashion purposes.

Parts of Eyeglasses

1. Lenses: The part of the eyeglasses that refract light to correct vision.
2. Frame: The structure that holds the lenses in place and sits on the wearer's face.
3. Temples: The long stems on each side of the frame that go over the ears to hold the glasses in place.
4. Nose Pads: The small pads on the bridge of the frame that rest on the wearer's nose for support.

Types of Lenses

Eyeglass lenses come in various types to address different vision needs:

• Single Vision Lenses: Correct either nearsightedness or farsightedness.
• Bifocal Lenses: Have two distinct viewing areas to correct both near and far vision.
• Progressive Lenses: Provide a smooth transition from distance correction at the top to near correction at the bottom.
• Photochromic Lenses: Change from clear to dark when exposed to sunlight, providing both indoor and outdoor functionality.

How to Care for Eyeglasses

1. Regularly clean lenses with a microfiber cloth and lens cleaner to remove smudges and dirt.
2. Store glasses in a protective case when not in use to prevent scratches and damage.
3. Get frames adjusted by a professional if they become loose or uncomfortable.
4. Have lenses replaced if they become scratched or if your prescription changes.

Study Guide Questions

1. What are the main parts of eyeglasses and their functions?
2. Explain the difference between single vision, bifocal, and progressive lenses.
3. How do photochromic lenses work, and what are their benefits?
4. What are some tips for caring for eyeglasses to prolong their lifespan?