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The last time I visited an optician was 3 years ago. The best time to visit is annually for regular checkup. So the best time for me to check my eyesight was yesterday. I went to visit several optical stores. Those with optometrist for their expertise advise.

To find out, I realize there were more types of glasses available

In the past, the only material that was used for the manufacturing of lenses is Crown glass. But now in days many different types of lens materials are used, like CR-39 Plastic, polycarbonate, mid-index plastic, spectra-light and 1.6 index plastic, 1.66 index plastic. Almost all plastics and polycarbonate are lighter in weight as compared to crown glass.

For start, there were 1.5 and 1.6 index plastic. I was told that 1.5 were thicker and uglier. So usually going for 1.6 index is much thinner and looks good on the person. I’m not sure of the 1.66 index plastic but I’m sure it is going to be expensive right?

Since I heard there were Carl Zeiss lens available for eyeglasses in contrary of the older times when we using Hoya, I decided to check out the prices given that I might be able to afford it. Before I dwell into the pricing matters, I learned a lot from the optometrist as well as the salesperon on the consideration when choosing lenses.

Aspheric Lenses

Here’s the summary from what I googled earlier:-

When choosing lenses, one should consider that:

• Each lens material has its own unique optical properties. Depending on prescription and intended use, certain materials perform better than others.
• Aspheric lenses provide superior peripheral vision for those with stronger prescriptions and also produce thinner edges than spherical lenses.
• Highly impact resistant materials such as polycarbonate and “Trivex” are required for children’s lenses as well as for all sport and other safety applications.
• Lens edge thickness depends on prescription, frame size and shape, center thickness and on the index of refraction of the material. Currently, there are eight possible choices of index of refraction ranging from 1.49 to 1.74. As this number increases, lenses become thinner for a given prescription in a given frame. Some of the manufacturers that make higher index, thin lenses are: “Seiko”; “Essilor”; “Hoya”; “Nikon” and “Optima”.
• Ultraviolet protection is recommended for all lenses that are used outdoors and for use with computer monitors.
• Sun lenses, whether prescription or non prescription must filter out at least eighty to ninety percent of visible light and must filter out all ultraviolet light. Polarized lenses offer the additional feature of blocking light reflected from horizontal surfaces and are a must for all water activities.
• “Transitions lenses” darken only with direct exposure to sunlight and do not work effectively behind the windshield of a vehicle.
• Fashion tints can be selected for appearance or to soften light in certain lighting conditions. They do not meet the standards required for sun wear.
• Scratch resistant coatings are necessary and should not be considered an option. Extra hard coatings such as “Essilor’s” “TD2” offer enhanced scratch resistance.
• Anti reflective treatments increase light transmission, reduce glare and reflections and greatly improve the appearance of lenses. The very thinnest lenses require this treatment, while it is optional on the others. Basic, low end treatments perform poorly. The best anti reflective treatments combine superior scratch resistance with hydrophobic and anti static properties, and are chemically bonded to the lens. Some key brands are: “Crizal Avance with Scotchguard”; “Hoya Super High Vision” and “Teflon”.
• Bifocal and trifocal lenses are made in many widths and depths to accommodate a variety of needs. Blended bifocal lenses are also available, but are generally not recommended.
• Specialty, occupational multifocal lenses can help with tasks that require intermediate or near vision in areas above eye level.
• There are over one hundred progressive lens designs made by numerous manufacturers including Varilux Lenses and Hoya Lenses. Early designs caused distorted vision for some wearers. Some of the “low end” lenses on the market today still cause this problem. Today’s premium lenses are more costly, but provide far superior visual performance. These modern progressive lenses include designs that maximize distance, intermediate or near visual acuity. Choices include many that have been created to work well with today’s shallower frames. Some of the available premium progressive lenses are made by: “Essilor”; “Varilux Lenses”; “Hoya”, “Seiko”; “Shamir” and “Zeiss”.
• Computer lenses perform best with anti reflective lenses. Light tints can also help to further reduce glare. Special progressive and bifocal designs that maximize intermediate and near vision are offered for those who can no longer focus well at these distances.

I was being recommended Nikon SEECOAT. It was said better. Aspheric glasses going to cost me RM550. Other is around RM420 to RM510. Carl Zeiss is double the amount. RM1080. >.<

Aspheric Comparison

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