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Eye Glasses

Before the traditional eye glasses that we have today were produced, instruments called reading stones were used.

It is said that the Roman statesman Seneca, in 1000 BC had used a glass globe filled with water, that acted somewhat like a magnifying glass to help him read many books.

The first mention of the use of eyeglasses comes from Venice in 1285 BC when two magnifying lenses were mounted into bone, metal, or leather frames.

These frames had an upside down ā€œVā€ shaped instrument that allows it to be balanced on the bridge of the nose. This was held by the hand.

It was four years later, also in Venice that history records the first mention of eyeglasses being used because normal eyesight was not good enough.

However, it took opticians nearly 400 years to invent the rigid sidebars that hold the spectacles on the bridge of the nose, thus freeing the hands.

The sad fact is that history is not able to tell us clearly who exactly invented the eyeglasses. Perhaps, we would never know.

As soon as the glass industry improved, glass became the main lens in eyeglasses.

The ides immediately spread throughout Europe and Asia, and in the 1780s Benjamin Franklin remains the first inventor to add something to the history of eyeglasses.

He created bifocals, which was to solve his problem of changing from reading glasses to glasses when travelling and sightseeing.

Therefore, he took the glass in his reading glass and in his travelling glass, cut them in half and fused them together.

This new instrument had two halves of the reading glass and two halves of the travelling glass, which solved his problem of changing lenses.

Eye glasses or spectacles are instruments that are made to correct a number of eyesight problems.

Today there is more of understandings of problems of sight, and depending on them glasses are created.

The secret lies in the quality and type of the lens. Lenses can be either clear crystal glass or plastic ground.

Concave glass is used to correct the eye condition called nearsightedness. In this condition, near objects are seen clearly, yet far objects appear unclear.

The concave glass corrects this condition by channelling the rays of light so that they meet together, and create an image of the object on light sensitive tissue at the back of our eye, called the retina.

Farsightedness is the opposite, where objects close appear unclear, yet those that are far are clear.

For this condition, the glass in the eyeglasses needs to be able to collect the rays of light and spread them across the retina to get a clearer image of things closeby.

These two conditions remain perhaps the most common of all eye conditions needing correction by eyeglasses.

Today eyeglasses come in not just to help us read and see things close and further away, they shield us from sunlight (sunglasses/shades).

Specialized sunglass lenses called polarized are used to shield from the intense glare of the sun, and are better than normal sunglasses.

Eyeglasses are also modified today to allow us to view 3-D movies and pictures.

As lens technology continues to improve, many people have turned to the convenience of contact lens which are soft plastic lenses inserted into the eye, to replace eyeglasses.

Even so, many still use eyeglasses, and research in different areas of it continues to help improve their quality and wearability.