Who Should Prescribe Glasses?

To make the correct prescription for glasses is a science that requires years of experience and strenuous study. To accept a prescription of glasses from an optician, who is only supposed to dispense glasses and not prescribe them, is like taking a prescription from a compounded rather than from a qualified doctor. In today’s world, where everything is commercialized, this tendency is on the increase and readers are warned not to encourage this when it concerns their spectacles. It is always advisable to take a prescription from a specialized eye clinic, the eye department of a hospital or an eye specialist where an eye test for glasses is performed by doctors trained and experienced in this science. In a specialized eye clinic, the doctor will also examine the eye as a whole organ and, after excluding any eye disease, will prescribe the spectacles. If an unauthorized person prescribes glasses he merely does a mechanical job, remaining unaware of any disease in the eye. Valuable time, therefore, is lost while glasses are made. There have been instances where persons with brain tumors and torn retina have been seen by unauthorized persons and glasses have been prescribed. The tumor is missed for years, resulting in the loss of sight and, subsequently, life. All opticians must associate with and seek the advice of an eye specialist when faced with an eye problem not corrected by spectacles-like cataract, retinal brain disease, glaucoma, etc.

Special Spectacles for Old Age-Bifocal/Trifocal/Multimodal

The science of optics has taken great strides in making and fitting of glasses for the comfort and relaxation of the wearer.

A person between the age of 40 and 45 years sometimes requires spectacles for the first time to read and write. This phenomenon in science is called presbyopia. It is due to the loss of elasticity of the human lens which makes one unable to focus on near and long distances with the same power. A 40 to 45 year old person with normal distance vision will need spectacles for close work only. He/she can use a single spectacle for close work or a bifocal with plain glass for distance and power glass for reading. Two powers in one glass are called bifocal. A bifocal spectacle has two different powers-up for distance and down for close work. Glasses can also be multimodal. Multimodal glasses are so designed that one single glass has several powers fitted to focus for all distances.

The wearer of bifocal and multimodal glasses needs a special working segment. Some have an oval or straight segment for reading. The wearer takes some time to adjust to this double power.

Dark Goggles

The use of dark goggles is meant to cut off harmful heat and radiation from the sun.

The most common coolers or tints in goggles are Crooke’s B (brown tints). The Bl, B2, B3 tints become increasingly dark brown. The darker shade after B2 is not advisable as it will interfere with your vision.

The other tints available in the market are:

(a) Ray Ban (Green) and

(b) Cruxite (Pink)

They come in several shades.

Polaroid Dark Glasses

These glasses are made of highly specialized lenses that are able to cut off all unwanted rays by the phenomena of internal reflection.

All-the glasses are equally advisable and can be chosen according to one’s preference of colors. Polaroid dark glasses are processed by shading them with specific chemicals that do not allow harmful heat and radiation rays to enter the eyes. Only the useful rays of light enter the eyes. The harmful rays are ultraviolet, infrared and gamma rays. They can cause heat bums and erode the layer of the eyeball.

Plastic Lenses versus Glass Lenses

Methods of making spectacles have advanced a great deal in the last decade. Spectacles of plastic lenses are also available, but at a higher cost. They are weightless or of light weight, which makes them comfortable to wear, especially when the power is high. Their disadvantage is that they scratch easily and must therefore be kept carefully