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  • Replacement Lens Considerations

  • Whether you are considering replacement lenses for frames you already have or are ordering replacement lenses for new frames, there are many considerations.  There are so many choices for lenses and coatings, it's easy to be confused about what's worth buying.

    A common mistake people often make when buying eyeglasses is not spending enough time considering their choices of eyeglass lens materials, designs and coatings. We think you should know how to choose the right eyeglass lenses for you.

    We carry all lens types, including Single Vision, Bifocals, and Progressive Lenses.   We'll talk you through various lens materials, such as glass lenses, plastic, polycarbonate, Trivex and high index lenses.  Trivex lenses for single vision distance viewing offer the strength and safety of polycarbonate lenses with better optics for people with modest corrections. Trivex also takes tint better than polycarbonate. 

    There are polarized lenses, transitions or photochromic, and tinted lenses.  Finally, we need to discuss the finishes such as anti-reflective, UV or polarized protection, scratch resistance, and mirror finishes.

    No eyes are alike. Which is why when it comes to choosing eyeglass lenses and helping you see your best, there are a variety of eyeglass lenses options specifically designed to help meet your individual vision needs.  You also then have Single Vision, Bifocals, Trifocals, or Progressive Lenses.

    Do not forget replacement prescription lenses for sunglasses either.  The right prescription lens can have a huge impact on how well your eyeglasses and sunglasses work for you. Make the best choice by considering the way you see, the things you do, and how you live.

  • Refraction Index

    The index of refraction (or refractive index) of an eyeglass lens material is a number that is a relative measure of how efficiently the material refracts (bends) light, which depends on how fast light travels through the material.

    Specifically, the refractive index of a lens material is the ratio of the speed of light in a vacuum, divided by the speed of light in the lens material. the index of refraction of CR-39 plastic is 1.498, which mean light travels roughly 50% slower through CR-39 plastic than it does through a vacuum.

    The higher the refractive index of a material, the slower light moves through it, which results in greater bending (refracting) of the light rays. So the higher the refractive index of a lens material, the less lens material is required to bend light to the same degree as a lens with a lower refractive index.  Lenses made of a material with a high refractive index will be thinner than a lens made of a material with a lower refractive index.

    The index of refraction of today's eyeglass lens materials range from 1.498 (CR-39 plastic) to 1.74 (a specific variety of high-index plastic). Therefore, when you choose lenses of the same prescription power and lens design, a lens made of CR-39 plastic will be the thickest lens available, and a 1.74 high-index plastic lens will be the thinnest.

    Don't be confused by this.  We have been in the optical business for over 20 years and will walk you through all of these decisions.  We always take your budget into consideration and your lifestyle.

  • Considerations for Eyeglass Lens Selection

    Lenses you choose are influenced by four factors:

    1. Appearance
    2. Comfort
    3. Vision
    4. Safety