Everything You Need to Know About a Patternless Edger
Edging is one of the final processes in the production of corrective eyeglasses. It is the process of making an optical lens conform to the size and shape of the intended frame expected to accommodate the optical lens. Conventional edgers are optometry devices that employ physical patterns, commonly plastic, to make the optical lens into the desired size and shape of the lens frame under consideration. However, advances in design and technicality were able to prove that the role of physical patterns can be performed electronically. Now, we have optical edgers that do not make use of physical patterns. Hence, they are termed as patternless.
Patternless edgers make use of probes that measure the frame of interest and store the information on the computerized equipment. The equipment takes over the cutting/edging process concerning the size and shape information on it.
History of edgers
The process of edging optical lenses did not begin with an automated pattern or patternless edgers. All of the work was initially done by hand. In the early times of eyewear usage, a glass cutter is used to outline the desired size and shape on the optical lens. The glass cutter is used to make indents along the outline, and the unwanted part of the lens is easily broken off. This handwork was quickly refined into being done with the aid of a lens pattern, and this gave smoother edges with improved specifications.
The first automatic edgers were rimless edgers with ceramic wheels. They produce flat edges. They contain grits and other agents. Several modifications to this archaic equipment led to the development of standard patterned edgers. Electronic advancements birth the production of patternless edgers described earlier.
Patternless edgers were introduced in the late 1980s. Although they are quite expensive, they offer great value for the price.
Indications to use
Patternless edgers are the current gold standard optometry device used in the edging process of eyewear production. Edgers may also be used in the production of non-corrective eyeglasses, but for this article, the use of this equipment in making medical lenses will be explored.
Many eye defects can warrant the use of corrective optical lenses. The most common eye defects that require a prescription for optical lenses are:
- Hyperopia or farsightedness: The eyeball is shorter than average. Light rays pass through the eye focus at a point behind the retina rather than focusing on the retina.
- Myopia or nearsightedness: This occurs when the eyeball is too long, and light rays focus at a point in front of the retina.
- Astigmatism: This is blurry vision caused by distortion (uneven curvature) in the shape of the cornea or lens. It usually presents with myopia or hyperopia.
- Presbyopia: This is caused by loss of elasticity of the natural lens, making it difficult to focus on objects clearly. It is often noticed later in life and relatively common amongst the elderly.
Other diseases of the eyes that may require the use of optical lenses at some point in the management include age-related macular degeneration, cataracts, glaucoma, keratoconus, and so on.
Specific considerations indicating a need for a patternless edger include the following:
- It is the edger of choice for office use. It offers sophisticated and automated features that are well suited for office laboratories. It can work with advanced layouts, including new generation specifications.
- They are needed to perform tasks such as bevel tilting and movements, wrap frame specifications, and production of highly customized lenses. All of these are required for current works in today’s optometry practice.
- Patternless edgers are the most convenient and operator-friendly edgers.
- Customer satisfaction is also maximally achieved with patternless edgers. They are needed by every upscale optometry service provider. They complete the edging process within minutes to a few hours, providing the feasibility of providing same day services. They also deliver the most professionally done and perfect eyeglasses.
Patternless edgers only require relatively light maintenance. They do not develop use complications except for some technical faults that will require a repair engineer. Two important functional parts of the equipment are the blocker and tracer. Possible problems include high pressures from the blocker, which may cause optical lenses to be damaged from increased pressure during tightening from a blocker. Also, most tracers make use of a stylus, which can allow measurement errors when particulate dirt settles on it.
Routine maintenance procedures for a patternless edger include:
- General Cleanliness: The laboratory environment should be clean. Clean the different parts of the equipment regularly, rinse grinding chambers, and close tracer covers.
- Calibrate the tracer regularly and change parts such as the cutter and grill as deemed fit.
- Seek manufacturer’s guide on equipment maintenance
The only alternative is the patterned edger, which is substantially disadvantaged in technology and capabilities. It could as well be noted that patternless edgers have no alternative in today’s ophthalmological practice.
The general specifications are highlighted as follows:
- Interface: Features a TFT LCD screen display, which can be about 5 – 7 inches diagonally. There are ports for the internet, computer, and a barcode reader.
- Minimum lens capacity of 17 mm and 80 mm maximum
- Wide diameter grinders up to 100 mm that can produce very curved lenses
- Automatic bevels which are customizable, relishing, or rimless bevels
- Varying lens types: The lens could be mineral, organic, index, trivex, acrylic or polycarbonates
- Power: AC 100-240 V, 50-60 Hz, power consumption is 1KVA
How they work
The simple distinguishing features in patternless edgers are the lack of a physical pattern and technological sophistication. Lens tracers replace the use of physical plastic patterns. These tracers can be a separate device connected to the equipment or incorporated into the equipment right from the factory. The tracers outline the frame measurements on the lens. The size and shape of the frame can be manually put into the tracer, or they could be sent digitally into it from any laboratory or frame retailer. Lens tracers can deliver perfect outlines of the frame measurements.
The blocker compartment prepares the outlined edges for removal by either the grinding chamber or steel blades. Manufacturers often design the edgers to deliver predetermined pressure to the lens edges. They also ensure that the lenses are cut with focal positions and optical center. Newer patternless edgers possess flexible blockers that deliver better lens edges, better curves, and frame grip. They work as if they are able to feel the lens and robotically discard unwanted parts.
The many automated processes made possible by this equipment help to appreciate them more. Typically, the convex surface of a lens is required. The lenses are, however, usually supplied with a hydrophobic layer of coating. Hence, there will be a need to mount to prepare the lens. This is done by dissolving the surface coat with organic solvents. The lens is then mounted with the aid of adhesives which hold it firmly in position. The grinder is then worked around the optical lens to cut/smoothen out the desired edges.
It is also necessary to mention that some earlier models of this equipment possess the ability to either use a physical pattern or the digital one. That era existed and has since been dominated by entirely patternless edgers.
Since the introduction of patternless edgers, numerous companies have produced several models. Technological advancements allowed for many modifications to be made upon each model being churned out. Essilor is a mother brand and one of the earliest manufacturers of the ophthalmic device. The company is based in France and still makes excellent edgers till today. The dominating brand in today’s market is NIDEK. Nidek Co. Ltd was founded in Japan and is a specialist manufacturer of ophthalmic equipment. Another top brand that cannot be overlooked is Santinelli®, a thriving American (based in New York) company with over 40 years of excellence. Luneau technology is also a market leader regarding patternless edgers. Other worthy mentions are Huvitz, WECO, Dia optical, VISSLO, and so on.
Patternless edgers may cost thousands of dollars, but they remain valuable and essential in the production of optical lenses. They are very durable, and this makes them cost-effective in the long run. They have revamped eyewear totally in a lot of ways. Optical lenses were known to be basic, unfashionable, and cliché. With the use of this equipment, highly customized lenses have become ubiquitously available and are now generally accepted by the public. This has boosted the confidence level of many patients, encouraging them to wear what they like.
Also, this device has been able to address the local belief of optical lenses that states that they cause more damage to the eyes in the long run. The different models make specialist eyewear devoid of production errors that can deter the confidence of many clients.