Characteristics of Various Functional Lenses

Progressive Multi-Focal Lenses
What are the obvious advantages of progressive lenses?
1.Continuous vision from far to near, clear at distance, intermediate and near ranges.
2.Aesthetic appearance with no visible dividing line.
3.No image jump.
4.Comfortable wearing experience, avoiding the trouble of frequently changing glasses.

Types of Lenses
-Suitable Users for Multi-Focal Lenses:
-Presbyopic people, especially early presbyopes.
-Those dissatisfied with wearing two pairs of glasses.
-Those dissatisfied with traditional bifocal lenses.
-Juvenile myopia patients.(Focus on lenses for slowing myopia progression in teenagers.

By occupation:People with frequent vision shifts; teachers (during lectures); supervisors (during meetings); card players, etc.
Unsuitable Users for Multi-Focal Lenses:
People with cervical spondylosis or migraine;Users with frequent reversed viewing distances, such as:high-altitude workers, people who often look up or sideways at close range (dentists, electrical maintenance workers), pilots, water & electricity workers, operators of large instruments, etc.

Notes for Adaptation:
Relatively long adaptation period;Adjust vision by turning the head;Pay attention to the distribution of visual zones.

Colored Lenses
Colored lenses are resin lenses dyed after substrate production, then hardened and coated.They enhance the fashion sense of the wearer.

PC Lenses
PC lenses are optical lenses made of polycarbonate, produced as thermoplastic resin lenses, while ordinary resin lenses are thermosetting

resin lenses.
Advantages: Ultra-high impact resistance, ultra-light weight;especially suitable for half-rim and rimless frames;environmentally friendly;currently the safest lenses in the world.
Disadvantages:Relatively low surface hardness;require special grinding wheels and methods for processing.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

How Much Do You Know About Resin Eyeglass Lenses?

Resin is a hydrocarbon secretion from various plants, especially conifers. It is valued for its unique chemical structure and its use in latex paints and adhesives. As a mixture of many macromolecular compounds, it has different melting points.

Resin can be divided into natural resin and synthetic resin. There are a great many types of resin, widely used in light and heavy industries, and commonly seen in daily life — such as plastics, resin eyeglass lenses, coatings, etc. Resin lenses are optical lenses made from resin through chemical synthesis, processing and polishing.
Features

A. Low density Due to gaps between molecular chains, fewer molecules per unit volume result in low specific gravity and light weight — only about 1/3 to 1/2 the weight of glass lenses.
B. Moderate refractive indexCommon CR39 (allyl diglycol carbonate) has a refractive index of 1.497–1.504.On the market, common resin lenses include aspheric, ultrathin, hardened and coated lenses with a refractive index of 1.67.Many manufacturers now offer 1.74 highindex resin lenses.

C.Surface hardness Lower than glass, so they are easily scratched by hard objects.They require hardening with silica, but still cannot reach the hardness of glass.Wearers must take good care of the lenses.

D.Good elasticity Organic molecular chains allow displacement, making resin lenses about 23–28 times more impactresistant than glass.Europe, the US and Japan prohibit children under 16 from wearing glass lenses.

E. Auxiliary functions Can be treated to provide protection against harmful rays, photochromic effects, and more.
F. Processability Excellent. Suitable for fullrim, halfrim and rimless frames.Permeable dyeing is available for custom colors.
G. Chemical resistance As an organic compound, resin lenses must not be used in acidic or alkaline environments.
H. Thermal properties Do not use above 60°C, as the antireflective coating may crack or peel off.
I. PriceVaries by quality, function, brand and grade.
J. Lens thickness design According to U.S. FDA standards, the minimum center thickness can be 0.6 mm, but strength decreases accordingly.For safety, manufacturers in Europe, the US and Japan generally set the center thickness to at least 1.0 mm for prescriptions over ±1.00 D.

Advantages and Disadvantages
Resin lenses are optical lenses made of resin. Compared with glass lenses, they have unique advantages:

Light weight
Resin: 0.83–1.5 g/cm³Optical glass: 2.27–5.95 g/cm³

High impact resistance
Impact strength: 8–10 kg/cm², several times that of glass.Not easily broken, safe and durable.

Good light transmittance
Similar to glass in the visible light range;Slightly higher in the infrared range;In the ultraviolet range, transmittance drops below 0.4 μm, and almost all light below 0.3 μm is absorbed.

Low cost
After making one precision mold, lenses can be massproduced by injection molding, saving time and cost.

Meet special needs
Aspheric lenses are easy to produce with resin, but difficult with glass.
Disadvantages:
Lower surface wear resistance and chemical resistance than glass
Easier to scratch
Higher water absorption These can be improved by coating.
The main drawback is a high thermal expansion coefficient, low thermal conductivity and low softening temperature, making lenses prone to deformation and degraded optical performance.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

Some Knowledge About Eyeglass Lenses

For a pair of eyeglasses, the quality of the lenses directly affects vision correction effect and wearing comfort. After years of development and technological innovation, eyeglass lenses have evolved into various materials and functions. So how do these lenses perform, and what are their advantages and disadvantages? Before choosing glasses, we need to learn about lenses in detail.
Glass Lenses

Glass was the earliest and most common material for eyeglass lenses.It features high hardness, resistance to deformation and scratching.During production, other substances can be added to adjust the refractive index for ideal optical performance.
Advantages:High material stability, good light transmittance, effective UV protection, and certain light absorption capacity.
Disadvantages:Fragile and relatively heavy, causing many concerns during wear;large chromatic aberration, which may reduce peripheral vision.
With technological advancement, glass lenses are gradually replaced by new materials.Due to obvious shortcomings in comfort, they are fading out of the market.

Acrylic Lenses
Acrylic lenses, commonly known as organic glass, are plastic lenses developed to replace glass.They are lightweight, low-cost, and easy to manufacture and process.
Advantages:Shatter-resistant, without sharp fragments when broken;suitable for secondary processing and widely used.They serve not only as optical lenses but also in instrument parts, automotive lights, transparent tubes, and even mobile phone and TV screens.
Disadvantages:Easily deformed by heat and poor wear resistance.Thus, they are mostly used for industrial safety goggles.

PC Lenses
PC lenses, also called space lenses or cosmic lenses, are a type of thermosetting material.They are extremely lightweight yet highly tough, and are often used in bulletproof glass.
Advantages:Strong UV resistance, not easy to discolor,impact resistance far superior to other lens materials.
Disadvantages:Poor wear resistance and require coating;the relatively soft material tends to deform under pressure,so they are not suitable for plastic frames or rimless frames.

Resin Lenses
PC lenses are actually a type of resin lens, but differ in processing from standard ophthalmic resin lenses on the market.As the name suggests, resin comes from plant secretions. It is valued for its special chemical structure and uses in latex paints and adhesives, and is widely applied in both light and heavy industries.
Advantages:Lightweight and impact-resistant, just like PC lenses.With UV-resistant elements added, they provide excellent UV absorption.
Disadvantages:Also poor in wear resistance and easy to scratch,with relatively low light refractive index.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

How Should Patients with High Myopia Choose Suitable Eyewear?

Which Lenses Are Best for High Myopia?
When selecting lenses for high myopia, patients should consider not only the cosmetic appearance after wearing glasses but also the protective benefits for ocular health. To determine which lenses are most suitable, it is important to understand the optical characteristics associated with high myopia.

The selection of lenses for high myopia should be evaluated from the following aspects:

1. Choose Lenses with a Refractive Index Above 1.61 Whenever Possible
The refractive index refers to the lens material’s ability to bend light and is the primary parameter determining lens thickness. Currently, the refractive index of most resin (plastic) lenses on the market ranges from 1.49 to 1.74. A higher refractive index results in a thinner lens. Generally, lenses with a refractive index of 1.60 or higher are classified as high-index or ultra-thin lenses.

For individuals with high myopia, lenses with a refractive index above 1.60 are strongly recommended. In addition, high-index glass lenses with refractive indices of 1.80 or 1.90 can be an alternative option, as they may be thinner than resin lenses. However, the production of such high-index glass lenses has become limited in recent years and often requires custom manufacturing, making them relatively expensive.
It should also be noted that resin lenses are commonly paired with semi-rimless or rimless frames for a modern and stylish appearance. However, for patients with high myopia, rimless frames are generally not recommended, as the exposed lens edge can make thick lenses appear even more noticeable.

2. Avoid Glass Lenses Whenever Possible
Glass lenses once dominated the optical frame market, but their disadvantages have become increasingly apparent. These include fragility, safety risks due to breakage, heavier weight, and the tendency to create pressure marks on the nose or ears. Such drawbacks can be particularly problematic for children and adolescents, who often find them uncomfortable.

With advancements in optical materials, resin lenses (including polycarbonate lenses) have emerged as a major innovation in ophthalmic optics. These lenses are lightweight, impact-resistant, safer against breakage, heat-resistant, and generally more comfortable for daily wear. As resin lenses became widely adopted, glass lenses gradually declined in popularity and often remain comparatively expensive.

For young patients with high myopia, resin lenses are generally considered the safer and more practical choice.

3. RGP Lenses: A More Ideal Option for Some Patients
Rigid Gas Permeable (RGP) lenses are high oxygen-permeable rigid contact lenses. For patients with myopia greater than −6.00 diopters who prefer not to wear spectacles, RGP lenses can be an excellent alternative.

Compared with conventional spectacle correction, RGP lenses typically provide sharper retinal image quality, a wider visual field, improved visual performance, and greater freedom from the physical constraints of frames.

For adolescent patients, RGP lenses may also help slow the progression of myopia and can be effective in correcting high astigmatism or irregular astigmatism.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

Anti-Fog Lenses: Fog-Free Vision, Hassle-Free Life

Anti-fog lenses are more than just fog-resistant. Innovative nano anti-fog technology ushers in a new era, replacing the need for anti-fog sprays. Our spray-free anti-fog lenses make fog prevention effortless just wear them as usual, and you can say goodbye to the hassle of relying on anti-fog sprays.

Crystal Clear Vision, No Fogging Powered by nano technology, The spray-free anti-fog lenses effectively prevent fog condensation on the lens surface. Whether facing extreme temperature changes or hot steam, your lenses will stay crystal clear, eliminating embarrassing inconveniences and giving you peace of mind all day long.
We strive for perfection in every high-quality product.

Precautions
When lenses get dirty, please clean them with a professional microfiber cloth provided by the optical shop. Do NOT use paper towels or rough fabrics, as these may scratch or damage the lens coating.

Lenses can be rinsed directly with clean water, then dried gently with a lens cloth.
In environments with extremely high humidity or drastic temperature changes, iridescent patterns may appear on the lens surface. This is a normal phenomenon and will not affect visual clarity.

Minor scratches on the lens surface have a self-healing function. However, do not scratch the lens surface with sharp objects.

Never clean lenses with chemical-containing liquids, such as detergents, laundry powder, soap, acetone, or alcohol.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

Stop Making Random Choices of Eyeglass Frames if You’re Highly Myopic

For people with high myopia, wearing thick lenses can easily add pressure to the bridge of the nose, and the heavy weight is also inconvenient. Therefore, choosing a comfortable and suitable eyeglass frame is particularly important. Today, we are going to explain what kind of eyewear frames are suitable for people with high myopia when wearing glasses.

Lightweight Material
The weight of the frame material is one of the factors affecting the overall weight of the glasses, which is closely related to the frame material. So the selected material must be lightweight. For people with high myopia, when choosing frames, you can pay more attention to materials such as pure titanium, tungsten carbon, thin-sheet acetate, and TR90. Frames made of these materials are generally lightweight, offering high wearing comfort, excellent durability, and resistance to deformation.

Geometric Center Distance Close to Pupillary Distance for Lens Fitting
The thickness of myopic lenses is mainly manifested in the horizontal direction of the frame glasses. Since the geometric center distance of most frames is larger than the human eye’s pupillary distance, in many cases, the temporal edge of the lens is significantly thicker than the nasal edge, and the temporal edge of the lens is exactly the part easily observed by others. Therefore, choosing a frame whose geometric center distance is close to the pupillary distance for lens fitting can make the thickness of the nasal and temporal edges of the lens similar, effectively reducing the thickness of the temporal edge of the lens and improving the appearance.

Non-metallic Materials Preferred
Large frames tend to highlight the thickness of high-myopia lenses, and they are heavier overall. If you want to avoid the peripheral part of the lens looking thick and reduce the weight, try to choose non-metallic frames, such as wide-leg acetate frames. The peripheral part of the lens can be covered by the frame legs, making it not easy to show the thickness.

Full-rim Frames Are a Better Choice
Due to the generally thick lenses for high myopia, rimless and semi-rimless frames will fully expose the thickness of the lenses. In addition, such frames are prone to deformation, which will lead to changes in the center distance of the glasses and the axial direction of the lenses, affecting the correction effect. Therefore, full-rim frames are the preferred option for people with high myopia.

Finally, we want to say that people with high myopia need to consider various factors when wearing glasses because of their high degree of myopia. You should not only choose lenses carefully but also pay attention to the frames. Do not ignore suitability and practicality just for the sake of aesthetics.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

Working Principles of Traditional and Digital Progressive Lenses

Traditional progressive lenses are made from semi-finished lens blanks with no cylindrical power (spherical power) on the front surface. Instead, spherical power is added to the back surface. However, this type of progressive lens is becoming obsolete, as it is less accurate than other available alternatives. The corridor (the area of the lens that corrects vision) is relatively narrow.
Digital progressive lenses this lens design delivers an optimal optical field of view when tailored to the wearer’s optical needs. Digital lens surfacing technology is primarily applied to progressive prescription lenses.

These digital progressive lenses feature wider zones for distortion-free near vision and distance vision. Another advantage of digital progressive lenses is high-definition vision in the intermediate zone (between near and distance vision). This enhanced visual performance is highly beneficial for computer work and other daily activities.

Digital lenses are computer-designed to achieve maximum clarity and accuracy. They are now more frequently recommended by optometrists than traditional alternatives due to their numerous benefits. One key advantage is that these lenses are custom-surfaced based on the wearer’s specific prescription, frame dimensions, and fitting position.

These factors are crucial for precise vision correction, owing to the lens design. Since the same optical frame may sit higher on one wearer’s face and lower on another’s, precise specifications and measurements are essential to ensure optimal comfort and optical performance. Progressive lenses optimized for computer use also feature wider, more precise corridors, resulting in improved peripheral vision. Additionally, digital free-form progressive lenses incorporate technology that reduces edge blur in the peripheral visual field.

The core difference between digital and traditional progressive lenses lies in the ability to customize the lens zones for individual wearers. Digital progressive lenses are calibrated to the wearer’s facial structure and eye positions to ensure the most accurate prescription correction.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

How to Choose Reading Glasses for First-Time Presbyopia Sufferers?

Presbyopia refers to the difficulty in focusing on nearby objects that occurs at a certain age. It is a natural phenomenon of age-related decline in human bodily functions, which typically manifests in most people between the ages of 40 and 45. Symptoms include blurred vision when viewing small text sufferers have to hold mobile phones or newspapers at arm’s length to read clearly. Vision tends to be sharper in well-lit environments, and the distance required to view a mobile phone screen increases progressively with age.

Once presbyopia sets in, wearing a pair of reading glasses is essential to alleviate eye fatigue. For those buying reading glasses for the first time, here are key guidelines for selection:

Opt for relatively wide lens shapes
Due to the convergence effect of the eyes when focusing on near objects, combined with reading and writing habits, the visual axis of each eye shifts downward and inward by 2.5 mm on the lens when viewing close-up objects, compared to the position when looking straight ahead at distant objects. Since the pupils are generally aligned with the horizontal midline of the lens during straight-ahead vision, the lens must be wide enough to ensure an adequate field of view for near vision. Specifically, the vertical height of the lens should be more than 30 mm contrary to the misconception that smaller lenses are better. Narrow lenses with a vertical height of less than 25 mm are designed for portable, temporary vision correction only.

Choose optical frame with a wide front but a small optical center distance (OCD)Most presbyopia sufferers are middle-aged or older, with fuller facial contours. As such, the horizontal width of reading glass frames is typically 10 mm wider than that of regular eyeglass frames. However, the near pupillary distance is 5 mm shorter than the distance pupillary distance. Therefore, the recommended optical center distance (OCD) ranges from 58–61 mm for women and 61–64 mm for men. To meet both the wide frame and small OCD requirements, lenses with a larger diameter must be used, and the optical centers of the lenses need to be significantly inward-shifted during the manufacturing process.

Prioritize durable and sturdy constructionReading glasses are intended for near-vision use. The diopter strength required for presbyopia increases incrementally: starting at +1.00 D (100 degrees) around the age of 40, it needs to be supplemented by +0.50 D (50 degrees) every 5 years thereafter. Additionally, reading glasses are put on and taken off dozens of times more frequently than myopia glasses. For these reasons, the components of reading glasses must be made of robust or high-elasticity materials. The electroplated parts should offer excellent corrosion and scratch resistance, and the lenses must undergo a high-quality hardening process. Overall, a qualified pair of reading glasses should maintain its shape, resist rust, and avoid severe scratching for at least 2 years of use. In fact, these durability requirements make high-quality reading glasses more demanding than comparable frames for prescription eyeglasses.

Selecting the right reading glasses is crucial for first-time wearers, as individual differences are significant. Factors such as height, arm length, eye usage habits, and presbyopia diopter strength vary from person to person. The diopter may even differ between the left and right eyes. Furthermore, some people may have concurrent vision issues such as hyperopia, myopia, or astigmatism alongside presbyopia. Wearing ill-fitted reading glasses for an extended period will not resolve vision problems; instead, it may cause eye strain, swelling, or headaches.

Therefore, when presbyopia symptoms emerge, it is advisable to first undergo a professional eye exam at a formal ophthalmology clinic or optical frame store. Finally, select reading glasses tailored to your specific eye condition. Never settle for inferior, cheap reading glasses out of convenience or cost-saving considerations.

As a professional eyewear supplier, we specialize in acetate eyewear, metal eyewear, and buffalo horn eyewear, offering style, function, and premium craftsmanship.

What Are the Differences Between Reading Glasses Priced at 10 USD and 50 USD?

According to incomplete statistics, the myopia rate among adolescents in China has been on the rise, and a growing number of teenagers have to wear glasses. However, besides adolescents, there is another group of people who need glasses senior citizens. As people age, they develop presbyopia and thus require reading glasses. Reading glasses are available not only in optical frame stores but also at street stalls, yet there is a huge price disparity: a pair costs just 10 USD at street stalls but hundreds of USD in optical frame stores. So, what are the differences between reading glasses priced at 10 USD and 50 USD?

Different Target Consumer Groups
Generally speaking, few elderly people buy glasses in optical frame stores; most customers are middle-aged people purchasing glasses for their parents. In contrast, the majority of buyers at street stalls are elderly people themselves. Due to their life experiences, elderly consumers are reluctant to spend money and think that any product that works just fine is sufficient, which is why they opt for 10-USD reading glasses at street stalls. On the other hand, middle-aged people who buy reading glasses in optical frame stores are more motivated by filial piety, and they also recognize that glasses purchased from optical frame stores come with better quality guarantees.

Different Service Standards
The biggest feature of buying reading glasses at a street stall is that you can try on as many pairs as you like and pay the vendor once you find a pair that suits you. But the experience in an optical frame store is entirely different, you will receive comprehensive and thoughtful service. First, a professional optometrist will conduct a diopter test for you, then recommend the most suitable lens package based on your exact prescription. After selecting the lenses, you can choose from a variety of frames, including metal and plastic options. Only those who have purchased reading glasses from both channels can truly appreciate the stark difference in service quality.

Different Product Grades
Many people who have bought reading glasses for their parents may wonder: The reading glasses sold at street stalls are also branded products, so why are they so cheap? The answer lies in product grading. Generally speaking, the reading glasses sold at street stalls are all low-grade products, with very few mid-to-high-grade options available. In contrast, optical frame stores rarely stock low-grade reading glasses and mainly offer mid-to-high-grade products, which explains the significant price gap between the two.

Therefore, as a professional eyewear supplier, we recommend that you avoid purchasing reading glasses from street stalls. Wearing reading glasses with an incorrect diopter can be detrimental to your eye health. For this reason, it is always advisable to buy reading glasses from a formal optical frame store, where you can receive a professional diopter check and purchase a pair of glasses perfectly tailored to your vision needs.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.

What Eyeglasses are Best for High Myopia?

In recent years, myopia has become increasingly prevalent, bringing significant inconveniences to daily life and work. Wearing corrective optical glasses remains the most common solution for myopia.

However, many people lack a clear understanding of how to choose eyeglasses based on their myopia degree such as what type of glasses, Optical frames, or lenses are suitable for -4.00D (400 degrees) myopia, and other related questions.

Optical frame Selection
People with high myopia have a wide range of options when choosing Optical frames and lenses. In terms of Optical frame styles: rimless, semi-rimless, and full-rim Optical frames are all viable. Generally, rimless Optical frames have degree limitations, they are not suitable for very high myopia and are recommended for those with myopia below -6.00D (600 degrees).

In terms of materials: both metal frame and acetate frame are applicable. Acetate frame typically offer rich color options, making them easy to match with different outfits. Metal frame especially pure titanium ones, boast excellent texture, they are lightweight and comfortable to wear without causing pressure on the nose or ears. Therefore, you can choose the Optical frame style, material, and color based on your face shape and personal preferences.

Lens Selection
High-quality lenses for high myopia should meet the following criteria:
Optical clarity with no color distortion;
Strong chemical resistance household solvents and chemicals will not damage the lenses;
Lower reflectivity than glass lenses, avoiding glare and eye discomfort;
Compatibility with multiple functional coatings, such as anti-radiation, scratch-resistant, oil-repellent, and anti-glare coatings.

A refractive index of 1.67 or lower is perfectly sufficient for most users. While it’s true that for the same prescription power, a higher refractive index results in thinner lenses—a key consideration for consumer aesthetics—there’s a critical trade-off to prioritize from the consumer’s perspective: sufficient is better than higher.

Why “sufficient is better than higher”?
For most people with high myopia, a refractive index of 1.67 is more than adequate. While it’s true that for the same degree, a higher refractive index results in thinner lenses (a key concern for high myopia patients seeking a more aesthetically pleasing look), there is a critical trade-off: the higher the refractive index, the lower the Abbe number. Below is a detailed analysis of the pros and cons to help you make an informed decision:

1. Higher Refractive Index (e.g., 1.74, 1.76)
Advantages:
Thinner and Lighter: The most significant advantage. For high myopia (e.g., above -8.00D), lenses with a refractive index of 1.74 will be noticeably thinner and lighter than 1.67 lenses, reducing the “bulky” appearance and relieving pressure on the nose.
Better Aesthetics: Thinner lenses fit more seamlessly into Optical frames, avoiding the “bottle cap” effect common with thick, low-refractive-index lenses for high myopia.

Disadvantages:
Lower Abbe Number: The Abbe number measures a material’s ability to disperse light. Higher refractive index materials (e.g., 1.74 polycarbonate or MR-174 resin) typically have an Abbe number around 30-32, while 1.67 lenses have an Abbe number of 32-36. A lower Abbe number means more chromatic aberration—when looking at objects (especially edges or bright light sources), you may notice slight color fringing (e.g., red or blue edges), which can cause eye fatigue during prolonged wear.
Higher Cost: The production process for high-refractive-index lenses is more complex, so they are significantly more expensive than 1.67 lenses (often 2-3 times the price).
Potentially Lower Impact Resistance: Some ultra-high refractive index materials (e.g., 1.76) are less tough than 1.67 or 1.60 lenses, making them more prone to chipping if dropped or impacted.

2. Moderate Refractive Index (1.67, Recommended for Most High Myopia Patients)
Advantages:
Balanced Optical Performance: With an Abbe number of 32-36, 1.67 lenses have minimal chromatic aberration, ensuring clear, natural vision without color distortion. This is crucial for reducing eye strain, especially for those who wear glasses all day (e.g., office workers, students).
Cost-Effective: Offering a good balance between thinness and price, 1.67 lenses are more affordable than higher-index options while still meeting the aesthetic needs of most high myopia patients (lenses are sufficiently thin for Optical frames of standard size).
Reliable Durability: Most 1.67 lenses are made of MR-7 or MR-8 resin, which have excellent impact resistance and scratch resistance (when paired with a quality coating), making them suitable for daily use.

Disadvantages:
Slightly Thicker Than Ultra-High Index Lenses: For extremely high myopia (e.g., above -10.00D) or those who prefer very slim Optical frames, 1.67 lenses may be slightly thicker than 1.74 lenses. However, this difference can be minimized by choosing Optical frames with smaller lens diameters or thicker rims to hide the edge thickness.

Conclusion
The core principle for selecting a lens refractive index is to prioritize optical clarity and comfort while balancing thinness and cost. For most high myopia patients (-3.00D to -6.00D):
A refractive index of 1.67 is optimal—it provides sufficient thinness, minimal chromatic aberration, and cost-effectiveness, making it suitable for long-term wear.
For those with extremely high myopia (above -6.00D) or who prioritize ultra-thin lenses (e.g., for aesthetic reasons), 1.74 lenses can be considered, but be aware of the potential for increased eye fatigue from lower Abbe numbers and the higher cost.

In summary, “sufficient is better than higher” there’s no need to pursue the highest refractive index blindly. Choose based on your myopia degree, wearing habits, and budget to achieve the best balance of vision quality, comfort, and aesthetics.

As a professional eyewear supplier, we are specialize in acetate eyewear and metal eyewear and buffalo horn eyewear.