Eyeglasses Lens Guide
When purchasing eyeglasses, many factors must be considered. Lenses are a crucial part of this process.
Eydology has prepared a lens guide to help you understand lenses and choose the right eyeglasses.
Lens Usage
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Single Vision:
Single vision lenses are standard prescription eyeglasses.
Single vision lenses provide only one type of vision correction, with the same prescription strength across the entire lens. They can correct nearsightedness, farsightedness, or astigmatism. This is the most common type of lens.
• Either far • Or near
But ❌ not both at the same time.
👉 Like a camera with a fixed-focus lens. -
Progressive:
Progressive lenses offer the closest thing to natural vision you can get in a pair of prescription glasses.They provide a smooth transition from near to far vision, incorporating all intermediate corrections to ensure clear sight at every distance.
• Top: Distance vision
• Middle: Computer / intermediate
• Bottom: Near / reading
The near-vision support comes from the ADD (Addition power).
👉 Like a camera lens with smooth zoom. -
Bifocal:
A bifocal lens means a lens with two credits of focus. A small portion of the eyeglasses lens is reserved for the near-vision correction. The rest of the lens is usually a distance correction.
• Top: Distance
• Bottom: Near (reading)
✔ Clear for far + near
❌ No smooth intermediate (computer) zone
❌ Visible line between the two parts
👉 Like a camera with two fixed focal lengths. -
Reading:
Reading lenses are prescription glasses designed for reading.
They provide optimal vision for reading or other close-up tasks, suitable for objects at reading distances ranging from 16 inches (approximately 40 cm) to 2 inches (approximately 5 cm).
If you notice your vision changing over time, struggle to focus on small print, or simply want to enhance eye comfort while reading, reading lenses can be highly beneficial.
Lens Type
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Blue Light Filter:
Blue light filter lenses reduce the amount of blue light reaching your eyes, helping to minimize harmful blue light emitted by digital devices. They improve sleep quality by blocking or absorbing blue light and UV rays from screens.
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Photochromic:
Photochromic lenses are eyeglass lenses that change color based on the amount of UV exposure. In bright sunlight, these lenses darken to protect your eyes; however, when you move indoors or UV levels decrease, they return to clear, allowing normal vision.
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Transitions® Brand:
Transitions® lenses are the brand of photochromic lenses, containing a patented photochromic dye. They are the ideal choice for your everyday wear, meeting all your corrective lens needs:
Vision
Visual comfort
Convenient protection against harmful UV rays and glare. -
Driving:
Driving lenses are specifically designed for driving, providing optimal visual experience and color contrast while on the road. They offer:
A night vision zone to help manage night myopia
An expanded distance zone
Significant glare reduction
What is index?
Lens index is a number that describes how thick or thin your lenses are. The higher a lens' index is, the thinner it becomes.
Recommended Lens Index
Lens index
Features
SPH
CYL
1.50 Standard Index
1.50 index lenses are thicker and heavier, best for low prescriptions
+1.00/-2.75 or below
0 to +/-1.5
1.57 Mid-Index
Thinner and lighter than 1.50 Index lenses.
+2.00/-3.75 or below
0 to +/-1.5
1.61 High-Index
Thin & Light lenses offer the best value for people who have moderate prescriptions and want a light lens.
+3.00/-5.75 or below
+/-2.25 to +/-3.0
1.67 High-Index
These lenses are great for people with moderate-to-high prescriptions.
+4.75/-6.75 or below
+/-3.25 to +/-4.0
Lens Coatings
Eydology offers a variety of lens coatings to help you customize lenses that best suit your lifestyle. Learn about the available lens coatings below to order the coating that meets your needs.
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Scratch-Resistant Coating:
This coating helps prevent minor scratches commonly found on standard lenses. It also acts as a protective layer, making your lenses more durable.
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Anti-Reflective Coating:
Light passing through lenses can reflect, causing glare when light bounces off the surface. Glare or reflections can be uncomfortable and may even impair vision in severe cases.
Anti-reflective coating reduces reflections and glare, enhancing visual comfort and reducing eye strain. -
UV Protection Coating:
UV coatings on eyeglass lenses block harmful ultraviolet rays from damaging your eyes.
UV protection filters out harmful UV400 (UVA and UVB) rays, lowering the risk of eye diseases like cataracts. -
Super Hydrophobic Coating:
Super Hydrophobic (water resistant) coating keeps water drop, dirt, and smudges off your lenses while making them easier to clean. Lenses with this premium coating stay sparkling twice as long.