Types Of Lenses

Single Vision Lenses:
Whatever we do - whether we are working, playing, reading or driving - we want to look great in our new eyeglasses. Essentially, we want perfect vision. These lenses are used to correct Myopia and Hypermetropia. They provide correction to the whole of the lens areas. A spherical lens has one dioptric power. A cylindrical or toric lens have a combination of two powers and this lens is used for correction of Astigmatism.

Bi Focal Lenses:
These type of lenses have two segments - one for distance and one for reading, combined in one lens. There is a visible line between the two segments. They come in 2 different designs to suit different uses and the customer's preference.

Kryptok Bifocal:
The inner segment is round in shape, and usually 28mm in size

Flattop or 'D' Bifocal:
The segment is in English letter 'D' and the size of the segment is usually 28mm. The position of the segment is de-centered for right eye and towards the nasal for left eye.

Hi-Index Lenses:
Normal lenses of high power are very thick with full aperture and when fitted on the spectacle the wearer finds it heavy and bulky. To overcome this problem, hi-index lenses were introduced. These lenses are up to 40% thinner and lighter than standard lenses.

The density / refractive index of Hi-Index lenses is more which makes the lens 20% to 50% thinner than normal lenses. Thus, allowing the wearer to choose any frame from the wide range available.
Advantages of Hi-Index compared to normal lenses:
  • They are 20% to 50% thinner and the wearer can be sure of having lenses that don't put weight on his/her nose
  • More discrete lenses offering a more aesthetic setting for the eye and yet allows for a wide range of frames. The wearer's eyes are no longer concealed behind thick lenses.
  • Ideally suited for AR (Anti-Reflection) coating to further eliminate short images and improve transmission.
  Organic Mineral
Normal 1.498 1.523
Hi Index 1.56 1.6
  1.601 1.7
  1.67 1.8
  1.74 1.9

When people reach the age of 40, they start to have difficulty focusing objects at close range. Single vision lenses can no longer be used for the entire range of vision from near to far. As well as, traditional bifocal lenses provide clear vision of objects in the distance and near ranges. Thus, everything in between remains blurred. And, the visible dividing line is a sign showing everyone that you are wearing bifocals.
Progressive lenses have different prescription segments blended onto the lens, but without a visible line. There is a gradual change from the distance vision at the top of the lens to the near vision at the bottom.
Many people find that the Progressive give them more natural vision from near to middle to distance, and are more relaxing to wear, as the progression imitates natural focusing and they can see better. In all Progressives, there are three main are: Distance, Reading and Intermediate.

OPTION A - Transitions TM:
They are unique variable tint lenses that offer all day comfort protection, versatility, value and style.
How do Transitions TM work?
  1. They contain sunlight-sensitive photo-chromic molecules that cause the variable tint to lighten and darken under different UV radiation and temperature conditions.
  2. They darken outdoors under high UV light and lighten indoors under low UV light.
  3. They become darker at low temperatures (cold climate) and lighter in hot conditions (warmer climate).
Why choose Transitions TM lens?
  • Eye health protection: Transitions TM lenses provide 100% protection from UV-A and UV-B radiation even when inactivated. This helps reduce the chance of developing cataracts.
  • Visual comfort: The variable tint in Transitions TM lenses adjusts to different conditions and helps absorb harsh sunlight to reduce glare.
  • Physical comfort: Made of plastic that weight up to 50% less than glass, they sit more comfortably on the nose.
  • Durability: Besides being shock-resistant, they have built-in scratch-resistance as well.
  • Versatility: Because the variable tint becomes clear indoors and darkens outdoors, they can be worn at home, work, play… anytime. They are versatile enough to provide all-day comfort and protection both indoors and outdoors.
Transitions is a registered trademark of Transitions Optical, Inc.

OPTION B - Transitions TM:
Transitions Lenses are the #1-recommended Photochromic lenses in the world.

Transitions Lenses change from clear to dark in the presence of ultraviolet light, and block 100% of harmful UV rays. Our innovative photochromic technologies have produced unparalleled lens performance in nearly every lens design and material, including shatter-resistant lenses, bifocals, trifocals, progressives, and standard and high index materials.
When you choose Transitions Lenses, you choose visual quality, visual comfort and convenient protection with these performance features:
  • Virtually as clear as regular clear lenses indoors
  • Even clearer with an anti-reflective coating
  • As dark as most sunglasses outside in bright light
  • Fast to activate
  • Fast to fade back
  • Block 100% of harmful UV rays
  • Reduce the effects of glare
  • Reduce eye fatigue
  • Improve contrast
  • Offer the right tint at the right time in changing light.

Who Can Wear Transitions® Lenses?
Everyone who needs protection from glare and UV rays can benefit from Transitions Lenses. They are appropriate for children, adults and patients with special eyecare needs. The tint level of Transitions Lenses adjusts quickly as light conditions change to provide convenient protection from glare and 100% blockage of harmful UV rays.

Children & Transitions Lenses
It's never too early to start caring for your children's eyes. Children are excellent candidates for Transitions Lenses. It is estimated that 80% of total lifetime exposure to UV rays occurs before age 18. Children are more susceptible to UV radiation because their eyes continue to develop into the teen years. Children also require safe, shatter-resistant lens materials. Transitions Lenses are the perfect solution - available in sturdy, lightweight, shatter-proof materials. Transitions Lenses provide the convenience of automatic protection by blocking 100% of harmful UV rays. They also offer increased comfort by reducing eye strain and fatigue. Transitions Lenses help you instill a lifetime of Healthy Sight habits by promoting good eye health in children.

Patients with Special Needs
Certain people develop a heightened sensitivity to light, known as photosensitivity, and are more susceptible to visible light. Photosensitivity can develop with conditions, such as diabetes or recent eye surgery. The condition can also be caused by taking certain prescription medications. Some medications, even those used to treat conditions not related to vision, can cause the eyes to be more susceptible to damage from UV rays. During product testing, eyecare professionals were asked if Transitions Lenses seemed a good choice for people with specific visual needs.

Active Adults
Protection from glare and UV rays is important for the comfort and quality of your vision today. It's also important for long-term care of your eyes. It's never too late to help protect against the cumulative effects of UV rays, which can lead to eye conditions that compromise the quality of your vision.

Photochromatic Lens: They can change from clear state to dark tint when exposed to sunlight. These lenses can be used throughout the year, indoors or outdoors, in all climates and for various activities. Another advantage of these lenses is that they are available in all lens material and design. Popular colors are Grey and Brown.

UV Lens:
UV-A is absorbed primary by the lens of the eye, although a small percentage penetrates the ocular media to reach the retina. UV-A is referred to as the "near" UV ray. UV-B the "middle wave" ultraviolet radiation is absorbed by the cornea and the lens but it can also reach the retina. UV-C is absorbed by the zone in the stratosphere and is called the "far" UV ray.
The intensity of UV rays exposure depends on
  • The season and the time of the day.
  • The number of cloudy and sunny days in the particular city.
  • The altitude at which the city is located. (It increases by 5% for every 1000 feet increase in altitude.)
  • Outdoor enthusiasts like sportsmen, athletes, architects, golfers, project engineers.
Protection from UV Rays:
UV exposure can be reduced by more than 75% by wearing
  • Regular sunglass with UV cut-off lens.
  • Transitions TM lenses.
  • Any lens with anti-reflection coating.
They give complete protection from UV rays even if you have normal vision. Doctors recommend these lenses whenever you are outside to ensure 100% UV-B protection.

Hard Coating:
It is a special coating done on plastic lenses and polycarbonate lenses to make them scratch resistant which means that a normal CR-39 when used by any customer tends to get scratched due to its softness and if they are hard coated then scratches caused due to normal day to day usage by the customer is protected by this coating.
The coating has a tendency of scratch resistance. It will not make the lens scratch proof. Scratch resistance means that the tendency of the lens surface to get scratched is reduced and scratch proof is that the entire lens will not get scratched at all.

High Level Dip Coating:
In this process first the lens is super cleaned by the ultrasonic, and then dipped in crystal lacquer, maintained by super clean environment and at sub zero temperature. The lens is then withdrawn from this lacquer by robot PC controls and goes through 2 types of polymerization.
1st stage: 75C for 5 minutes.
2nd stage: 115C for 2 hours.
  • The best hard coat available in the market.
  • Highly durable and virtually scratch proof.
  • Best results of anti-reflection coating achieved with this hard coating.

AR (Anti-Reflection) coating:
To improve both the vision through the lenses and the appearance of the glasses, an anti-reflective coating (also called AR coating) is applied. AR coatings are similar to the coatings found on microscopes and camera lenses. They consist of several layers of metal oxides applied to the front and back lens surfaces. Because of the layering effect, AR coatings sometimes have a hint of green or purple color, depending on the individual manufacturer's formula.
Each layer is scientifically calculated to block reflected light. The result is that you'll see a reduction in glare, annoying reflections and halos around lights. This is a great safety benefit when you're driving at night.
Also, anti-reflective coating reduces both internal and external reflections on the lenses themselves, creating a nicer cosmetic appearance. Internal reflections appear as rings that make lenses look thick. External reflections mask your eyes from a clear, complete view when someone is looking at you. So with an anti-reflective coating, eyeglass lenses appear thin or non-existent, and your eyes look more natural.
Anyone on TV or whose photo is taken often benefits tremendously from the coating, but really, all eyeglass wearers would benefit from an anti-reflective coating from a cosmetic point of view. If you have a strong prescription, you can use the AR coating in conjunction with high-index lenses to make your glasses look and feel as thin as possible.
With sunglass lenses, an AR coating is better applied only to the back surface of the lens (the surface nearest the eye). Because sunglass lenses are so dark, the AR coating can wind up looking smeary on the front surface. Coating the back side helps reduce the reflections of light that enter from behind you and bounce off the surface into your eyes. A back-side coated sun lens is much more comfortable than an uncoated sunglass