Eyeglasses are an essential part of many people’s lives, providing them with improved vision and clarity. But what goes into creating a great pair of glasses? In this comprehensive guide, we will explore the intricate process of crafting high-quality eyewear that meets the unique needs and preferences of each individual. From understanding how the eye focuses to the detailed steps involved in lens production, we will delve into every aspect of creating the perfect pair of glasses. So, let’s embark on this journey to discover the art and science behind creating exceptional eyewear.
Understanding Vision Basics
To fully appreciate the intricacies of creating glasses, it’s essential to understand how the eye focuses. The eye consists of the retina, a complex layer of cells at the back of the eye that reacts to light and sends signals to the brain. The brain then translates these signals into the images we see. The eye relies on a lens and cornea to focus the incoming light onto the retina, ensuring a clear and sharp image. The lens, in particular, plays a crucial role in bending the light to match the curve of the retina. However, various factors can cause the eye to be out of focus, leading to vision problems such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. These vision issues can be corrected using lenses that adjust the focal point onto the retina.
How Lenses Work
Lenses are the core component of eyeglasses, and they work by bending light to compensate for the eye’s focusing problems. A lens can be compared to a prism, which bends light as it passes through. In eyeglasses, a lens is two rounded prisms joined together. How the lens is curved determines whether it is a plus lens (thickest in the middle) or a minus lens (widest on the edges). Plus lenses move the focal point farther back, while minus lenses move it closer to the lens. By placing the appropriate lens in front of the eye, the focal point can be adjusted to compensate for the eye’s inability to focus correctly.
Determining Lens Strength
Lens strength is measured in diopters (D) and indicates how much the light is bent. The higher the diopter, the stronger the lens. The lens strength is determined by factors such as the lens material and the angle of the curve that is ground into the lens. A prescription for eyeglasses typically includes the base (spherical) strength, cylinder strength (if needed), cylinder axis orientation, and bifocal segment strength (if applicable). These details help the optician create lenses that precisely match the individual’s prescription.
The Lens Making Process
Now that we have a basic understanding of how the eye focuses and how lenses work, let’s dive into the lens-making process. Lens production involves several steps, from selecting the appropriate lens blank to shaping and fitting the lens into the chosen frame. The following sections will provide an overview of the lens-making process and the intricacies involved at each stage.
Step 1: Choosing the Lens Blank
The lens production process starts with selecting a lens blank. Lens blanks are made in factories and come in various materials, shapes, and sizes. The lab technician chooses a lens blank that matches the desired material and base curve. If a cylinder curve is required, an additional segment may be included in the lens blank.
Step 2: Marking the Lens
To ensure accurate lens production, the optician marks the lens blank with essential reference points. If a cylinder curve is present, lines are drawn on the front of the lens to define the cylinder axis orientation and the 180-degree line. The optical center of the lens may also be marked slightly above the segment edge.
Step 3: Protecting the Lens
To safeguard the front surface of the lens during the grinding process, a special tape is applied. This protective covering prevents any damage to the lens surface in traditional methods.
Step 4: Preparing the Lens for Grinding
In this step, the lens is prepared to fit onto the generator, a machine capable of grinding two curves simultaneously. A chuck receiver, known as a lens block, is attached to the front of the lens over the protective tape. If a cylinder curve is present, the lens is oriented to match the cylinder sweep axis of the generator.
Step 5: Grinding the Lens
The lens is inserted into the generator, and the grinding process begins. The curves are set, and the lens is generated by sweeping the grinding wheel. Water is used to cool the lens and wash away the cut material. The lens thickness is determined by factors such as the curve type, lens material, and specific requirements.
Step 6: Sanding and Polishing
After generating the lens, it is taken off the generator and placed in a sanding machine. The lens is sanded to remove any marks left by the generator. Next, the lens is polished using felt polishing pads and a polishing compound, resulting in a clear and scratch-free lens.
Step 7: Shaping the Lens
The lens is now ready to be shaped to fit the chosen frame. A linear lathe, known as an edger, is used for this purpose. The lens is chucked into the edger, and a pattern in the frame’s shape is inserted. The lens is brought into contact with a grinding wheel or steel blades, which shape the lens according to the pattern.
Step 8: Lens Inspection and Additional Coatings
After shaping, the lens block is removed, and the lens undergoes a thorough inspection. Any necessary coatings, such as anti-reflective or scratch-resistant, may be applied to enhance the lens’s performance and durability.
Boerne Vision Center has lens making equipment at both the Boerne and Fair Oaks Ranch locations. Our newer technology in Fair Oaks replaces the traditional lens making step 3 to step 7 with vacuum blocking and lens milling technology.
Step 9: Fitting the Lens into the Frame
The lenses are now cut and shaped to fit into the chosen frame. If tinting is required, the lenses are dyed at this stage. The lenses are prepared for insertion into the frame, ensuring a precise fit and alignment. Special tools and techniques may be used to ensure the lenses are securely and accurately fitted.
Step 10: Final Touches
The lens production process concludes with final adjustments and quality checks. The lenses are inspected for defects or imperfections, and any necessary refinements are made to ensure optimal performance and comfort.
Additional Services and Customizations
In addition to the standard lens production process, Boerne Vision Center offers additional services and customizations to cater to individual needs and preferences. Some of these services include:
Quick Turnaround Time with In-House Lab
Boerne Vision Center is equipped with an in-house lab in each clinic that allows us to offer a quick turnaround time for lens production. This ensures that customers receive their glasses promptly, minimizing waiting times and providing a more convenient experience. Talk to our opticians if you need your glasses made while you wait! Also if you already have a frame, we can put your new prescription in them.
Chemistrie Clips: Transforming Glasses with Versatility
Chemistrie Clips is a revolutionary accessory that allows individuals to transform their prescription glasses into prescription sunglasses, readers, computer glasses, and more. These ultra-thin, high-quality lenses attach directly to glasses frames using small magnets, providing a versatile and affordable option without the need for additional pairs of glasses. Chemistrie Clips are custom-made to fit virtually any frame and prescription, making them a convenient and stylish solution for eyewear customization.
Custom Engravings on Lenses
For those looking for a unique and personalized touch, Boerne Vision Center offers custom engravings on lenses. These engravings can include names, initials, logos, or decorative designs, adding a distinctive flair to your glasses. One of our staff is super excited to engrave tiny paw prints with her dog’s name on her next pair of glasses.
Safety Eyewear: Meeting OSHA Standards
Eyewear providers may also specialize in safety eyewear, offering lenses that meet Occupational Safety and Health Administration (OSHA) standards. These lenses provide enhanced protection for individuals working in hazardous environments, ensuring optimal safety and visual clarity. Boerne Vision Center is proud of their expertise in occupational vision and safety. Let us know about your occupational needs and we can recommend eyewear that will feel great and keep you safe on the job.
Drill Mounts: Customizable Frames and Shapes
In-house labs like Boerne Vision Center may offer drill mounts, a type of frame where the lenses are secured by drilling small holes in the lens and attaching them to the frame using screws. This allows for greater customization in frame shapes and sizes, giving individuals more options to suit their unique styles and preferences. Think rimless “heart shaped” glasses in your prescription.
Creating a great pair of glasses involves a meticulous process that combines scientific principles with skilled craftsmanship. From understanding the eye’s focusing mechanism to grinding and shaping lenses to precise specifications, eyewear providers strive to deliver exceptional eyewear that enhances vision and meets individual needs. With additional services such as quick turnaround times, customizable Chemistrie Clips, custom engravings, safety eyewear, and drill mounts, eyewear providers go the extra mile to ensure customer satisfaction and provide a personalized eyewear experience. So, the next time you put on your glasses, take a moment to appreciate the intricate art and science that goes into creating the perfect pair.