Similarly, a monocle can be observed conspicuously, also with a convex lens of the same sort, in the portrait of Pope Leon X painted by Raphael in 1517. Additionally, a pair of close vision eyeglasses can be seen in the painting known as "The Calling of Saint Mathew" painted in 1599 by the famous Lombard painter Michelangelo Merisi, better known as The Caravaggio.

In the beginning, only convex lenses were used, which only corrected Presbyopia and in some cases farsightedness. These convex lenses were created by cutting, grinding and polishing a transparent quarz-berilium based type of aquamarine. One of the first concave lenses, to correct nearsightedness, is clearly represented in the beautiful iron-mounted eyeframes painted by the Crete painter Domenikos Theotocopoulos, better known as El Greco in his portrait of Fernando -Cardinal of Toledo- Niņo de Guevara in 1600. Unfortunately, superstitions of the Middle Ages and even more so, the religious prejudices propagated by the Holy Inquisition, delayed for many years the initial success of the dissemination of eyeglasses as they were considered, by many ignorant fanatics, as "diabolic instruments to improve the gift of eyesight given by God". To combat this unjust situation, the principal traders of this incipient industry, who were already established in Europe, found the support of the Catholic Church by naming Saint Jerome himself as the Patron Saint of the Guild of Eyeframe Manufacturers citing the detail of the eyeglasses that are shown hanging at his side while sitting on a desk in the fresco painted by Ghirlandaio.

The continuous availability of new optical lenses, did more than improve the eyesight of the users as they led principally to the invention and further perfection of first, the microscope and then of the telescope. The Dutch eyeglass manufacturer, Zacharias Janssen, along with his father, was the inventor of the first compound microscope (around 1590). As this was a rather crude and rudimentary instrument based on a convex objective and a concave lens, it allowed only for minimal magnification.

In 1602, the German astronomer and mathematician Johannes Kepler, basing his theory almost completely on the ideas of the Arab mathematician Alhazen, made the first scientific study of the General Principles of Optics, proving that Presbyopia and Myopia could be compensated with convex and concave lenses respectively.

The invention of the telescope is attributed to three Dutch men, all of them eyeglass manufacturers. Zacharias Janssen, Hans Lippershey and Jakob Metius each invented separately, a crude and rudimentary instrument in 1608 by noting that a concave lens, upon moving it away from the eye, allowed them the magnification of far-away objects.



However, one year later in 1609, the Italian Galileo Galilei perfected the telescope notoriously by adapting a convex lens in one end and a concave lens on the other end of the instrument, thus achieving in principle a 3x magnification. That same year, Galileo built another telescope with an 8x magnification. The next year, in 1610, Galileo polished the lenses himself and manufactured a telescope with 33x magnification and subsequently discovered the mountains and valleys of the Moon, the apparent canals in Mars, the phases of Venus, Saturn's rings, four of Jupiter's twelve satellites and the Solar spots and flares.

In 1621, the Dutch mathematician Willebrord Snell, commonly known as Snellius, made a landmark contribution when he postulated the Law of refraction, stating and confirming that "upon inciding light on a refracting medium, water or glass for example, the refraction produced is constant and permanent". The final bases were laid for the development of the modern optical industry shortly thereafter with the notable research on refraction by the Dutch physicist Christiaan Huygens in 1655, of the octant by the British astronomer Robert Hooke in 1659 and the establishment of the Laws of Decomposition of Light in 1666 by the distinguished British mathematic-physicist Sir Isaac Newton.

It was not until 1673 when the Dutch medic Anton van Leeuwenhoek perfected the microscope by inventing a simple instrument based on a potent convex lens with a large magnifying power, which allowed him to make important discoveries by observing for the first time, the life, form and movement of many microorganisms hitherto unknown.

In 1784 Benjamin Franklin invented the bifocal lenses, by dividing them in two lenses, one convex for near vision in the lower part and one concave or convex, as needed, for far vision in the top part, fitting both lenses in the rims of the same eyeframe. Bifocals of the "cemented" type were invented in 1884, the "executive" type in 1908, the "one piece type" in 1910 and the "fused" type in 1916. Trifocal lenses were invented shortly thereafter and the multifocal and progressive lenses only recently.

Until the middle of the XIX Century, astigmatism was still considered an authentic curiosity to such a degree that until then and for almost three centuries before, it was attributed to the famous Greek painter (better known as El Greco who lived and painted most of his artworks in the city of Toledo, Spain) whose work shows a strange peculiarity in his vision and details the same elongated style of the characters in all his paintings.

The British medic and physicist Thomas Young was the first to discover in 1801 the interferences of light and the first to diagnose astigmatism. He was also the first to explain in 1804 that the capacity of the eye to clearly focus at different distances is owed to changes in the form of the eye's own lens, the crystalline.

It was not until the year 1927 though when the celebrated British astronomer Sir George Airy made the first attempt to correct astigmatism (his very own) with a cylindrical lens, unfortunately he did not correct it altogether. However, this condition was finally and firmly scientifically diagnosed and corrected with a convex cylindrical lens by the Dutch ophthalmologist Frans Cornelis Donders in 1864. Today, astigmatism is corrected with a cylinder in the concave face of the lens, which makes them more aesthetic and practical.

After almost 100 years of painstaking research, at the end of the XIX Century, the first high quality ophthalmic lenses appeared, when Ernst Abbe and Otto Schott began manufacturing them in Germany in 1885.

While George Washington used square lenses in an iron frame with long temples almost 250 years ago and the first rimless eyeframes came out only in 1840, today eyeframe and eyeglass forms vary greatly with fashion and are directly influenced by it. Designer eyeglasses abound and many are purchased and worn for the sake of fashion not just vision correction. With such influences, the manufacture of fashion eyeframes represents a sector of the world economy worth several billion dollars.




©2002 Styloptic Internacional. All Rights Reserved | Website Development by Pantages Studios