pros and cons of wearing spectacles

11
Pros and Cons of Wearing Spectacles Prepared By Mostafizur Rahman

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Page 1: Pros and cons of wearing spectacles

Pros and Cons of Wearing Spectacles

Prepared By

Mostafizur Rahman

Page 2: Pros and cons of wearing spectacles

Spectacles are the most widely used visual instrument in the world

Spectacles, also known as Glasses, are frame bearing lenses worn in front of the eyes.

They are normally used for vision correction or eye protection.

Spectacles In Brief

Page 3: Pros and cons of wearing spectacles

Spectacle Users

Approximately 207 million people wear glasses. 

About 64% adults wear eyeglasses. Nearly 3 million children under 4 years

wear spectacles.

Page 4: Pros and cons of wearing spectacles

History of Spectacles

Chinese used special type of spectacles to protect their eyes in hazardous situation.

Egiptians first invented the method of magnification of a particle eith the help of polished rock crystal.

Eyeglasses first appeared in Pisa, Italy, around the year 1286.

The first known artistic representation of eyeglasses was designed about 50 years latter.

Page 5: Pros and cons of wearing spectacles

Types of Spectacles

Spectacles are mainly of two types: Convex Lens Concave Lens

Some other types of Spectacles:

Photochromic Lenses

Bifocals

Trifocals

Varifocal

Page 6: Pros and cons of wearing spectacles

Spectacles MaterialsSpectacle frame consist of:

Metal Frame Pure Titanium frame Non-Allergenic Nickel coated frame Stainless steal frame Titanium alloy Frame

Plastics Frame

Page 7: Pros and cons of wearing spectacles

Spectacles Materials

Lens Materials:

Glass Lenses

Plastic Lenses (CR39)

Hi-Index Lenses

Polycarbonate Lenses

Aspheric Lenses

Page 8: Pros and cons of wearing spectacles

How To Take CareKeeping glasses in a hard case

Cleaning with warm soapy water

Taking off before sleeping

Keeping the Screws of the spectacles Tight

To avoid touching the lens while removing from

eyes

Page 9: Pros and cons of wearing spectacles

Choosing Proper Spectacles

Light WeightLeast ThicknessComfortable FramePhotochromic EyeglassesAnti-Reflective CoatingAnti Scratch Coating

Page 10: Pros and cons of wearing spectacles

Any Questions

?

Page 11: Pros and cons of wearing spectacles

Thanks For Listening