Are My New Prescription Glasses Too Thick?

It is not unusual to experience some discomfort or doubt when first transitioning to new prescription glasses. One common concern is the thickness of the lenses. Understanding the factors that contribute to the thickness and exploring potential solutions can help alleviate these concerns.

Factors Contributing to Lens Thickness

Several factors can influence the thickness of your new prescription glasses:

Prescription Strength

Higher prescriptions generally result in thicker lenses. If you have recently changed your prescription, the new lenses may appear thicker than your old ones. This is a normal part of the adjustment process.

Lens Material

Lens material also plays a significant role in determining lens thickness:

High-index lenses: These lenses are thinner and lighter, especially for stronger prescriptions. They are a popular choice for individuals with high prescriptions. Standard plastic or glass lenses: These lenses are typically thicker but can be more durable.

Frame Choice

The style and size of the frames can affect how thick the lenses appear. Smaller frames often require less lens material, making them appear thinner. Conversely, larger frames may accentuate the thickness of the lenses.

Addressing Visual and Comfort Concerns

If the thickness of your new glasses is visually unappealing or uncomfortable, it is best to discuss this with your optician. They can explore options such as:

Switching to high-index lenses, which are thinner and lighter. Opting for a smaller frame, which can reduce the appearance and weight of the lenses.

It is important to ensure that your glasses fit well and are comfortable to wear. Any issues with heaviness or awkwardness should be addressed with your optician.

Understanding the Manufacturing Process

Lenses are intentionally made from the thinnest blank that will support your prescription and still have the strength to prevent cracking or breaking under normal use. This ensures that the lenses are both effective and comfortable:

Common Lens Materials

Common lens materials include:

Standard plastic lens: These lenses are cost-effective and durable but may be thicker. High-index materials: These materials, such as 1.6, 1.67, and 1.74 index plastic, are thinner and lighter, even for stronger prescriptions. Other specialized materials: Some materials, like strontium titanate, diamond, zinc sulfide, titania, and silicon carbide, are used in specialized applications and are not typically sold for everyday wear.

Managing Visual Perception and Comfort

While higher index materials can reduce lens thickness, they may introduce some downsides:

Color fringe: This optical artifact can be noticeable, especially in cheaper high-index lenses. Cost: Higher index lenses are typically more expensive.

Prescriptions involving more than 5 or 6 diopters tend to get thicker, but this can be mitigated by choosing higher index materials. Up to one-third of the thickness can be reduced through this method.

The Science of Lens Manufacturing

A chart illustrating the thickness reduction from standard plastic lenses using different materials is shown below:

Chart showing how thickness can be reduced from a ‘standard plastic’ lens thickness by using other materials. The 5 materials on the right are not sold for glasses and would require a custom build. They are included to show what is possible, not necessarily what is practical.

Choosing a smaller frame can also help reduce lens edge thickness, providing a more aesthetically pleasing appearance. Unfortunately, high-index lenses do not prevent the appearance of abnormally small or large eyes when viewed from the front. Custom frames with very small lenses can be a solution.

Conclusion

While the thickness of your new prescription glasses is a valid concern, understanding the factors that contribute to lens thickness and discussing options with your optician can help address any issues. Whether through material choices, frame selection, or custom builds, there are solutions available to enhance the comfort and appearance of your prescription glasses.