The other half is the lens installation. Even if you are supplied with the best lens material, a poor installation by a technician will result in lenses that offer poor vision and you will have wasted your money. With Crystal Vision Lenses, you can be assured that you are getting the exact lens you ask for, and it is being installed with the very highest skill, attention to detail, and quality control. Eyeglass lenses are simply a carved block of clear plastic.
Lens quality is determined by four factors: 1 The clarity of the plastic 2 The precision of the carving 3 The accuracy of the prescription and PD measurement, and 4 The accuracy of the cutting of the lens to fit your frames. Several people are involved in the making of glasses lenses. If any one of these people makes a mistake, a loss in vision correction in the lenses will result.
The store you choose to make your lenses must insist on quality at every level in order for you to receive the best quality product. This kind of quality control is essential in order to ensure consistent results.
The plastic maker does the surfacing for stock lenses. The lens laboratory does the carving for surfaced lenses. Optometrist tend to write more accurate prescriptions than ophthalmogists. It is not uncommon for an eye doctor to change a prescription if the first prescription is not taken carefully, while laying the blame on the maker of the eyeglass lenses. Your eye doctor may not write the pupil distance measurement on your prescription unless you ask, in an effort to prevent you from buying glasses lenses at a different store.
This is an illegal practice. This could be an eyewear store employee, or lens laboratory. There are different types and qualities of blanks. The quality of the blank is determined by the clarity, meaning the absence of small bubbles or inconsistencies which can only be seen with a microscope. The lower lens quality and less expensive plastics have more miasms that, although you cannot see them with the naked eye, can still add up to decreased visual acuity.
Crystal Vision Lenses only use better or best quality lens plastic made by well-known plastic suppliers. We inspect every lens that we receive several times to ensure that it meets our standards. All of our suppliers have unconditional return policies for defects in lens quality. There are two basic ways of cutting lenses, depending on the prescription.
Single vision lenses that are in the stock range are usually surfaced by the plastic makers in bulk by huge computerized machines. These lenses are then shipped to optical stores so that the store employees can edge the lenses into the frame.
Most multifocal lenses, and all lenses that fall outside of the stock prescription range, must be fashioned custom for each prescription. In these cases, plastic blanks chunks of plastic are shipped to lens laboratories where they are carved surfaced for each individual prescription. There are hundreds of lens laboratories around the country, several in each state.
A typical lens laboratory will do a minimum of a few hundred lenses a day with a large staff of highly trained and experienced technicians. A few optical stores like Lenscrafters have small surfacing facilities in each of their stores doing much smaller lens volume.
To surface a lens, the lens laboratory takes the blank and puts it through a series of grinding machines, which grinds the surface the lens and shapes it exactly to the specifications of the prescription. Lens laboratories also provide other services like edging and mounting, which optical stores can choose to use or not, depending on whether they want to do that work themselves. As with any custom service, the quality of the surfacing and any other services that the lab provides— is determined by the experience and the expertise of the laboratory, its personnel, and the equipment it uses.
We only use labs that employ a large staff of highly trained technicians, doing a large volume of lenses every day. At Eyeglasses. Most of our orders require stock lenses; all of our custom surfacing work is done by lens laboratories. The laboratories that we use each have many years of experience and do thousands of lenses each week. Each lab that we use inspects each lens several times during the manufacturing process. When we receive the finished product from the lab, we do our own final inspection.
The optometrist OD or ophthalmologist MD that issues the prescription is not involved in the fashioning of the lens, but the prescription they issue is crucial to the overall effectiveness of the lens. Occasionally the OD or MD can issue a prescription that is not quite right. Also, it is possible for your eyes, and your prescription, to change rapidly during some stages of your life.
Normally an optical store employee will take your PD measurement when you go to buy glasses. If you want more freedom to choose where to buy your eyeglasses, you should ask your optometrist or ophthalmologist to measure the PD during your exam. Usually they will not measure the PD unless you ask them to. If you have your PD measurement and your prescription when you leave your eye doctors office, then you can buy glasses and lenses at any eyewear store. With your PD and your prescription, you will not be forced to go to an optical store to get your PD measurement, and then feel obliged to buy glasses from that store.
Edging is performed in a number of different ways. It can be done at the lens laboratory, or in the optical store. Either way, it is not required in any state that the edging be done by a licensed person. About one-half of the states in the United States have opticianry laws. The edging for most glasses made in this country is not performed by a licensed professional. However, all of the edging that is done for Eyeglasses.
That person has a very high skill and accuracy level that we have found to deliver very high quality. Toggle navigation. Replacement Lenses Why pay the additional cost of new costly frames for your regular eyeglasses or sunglasses along with the cost of new lenses just because of a broken, cracked, or scratched lens.
Choosing the Lens Type You now need to choose your lens type: single vision, bifocal, trifocal, or progressive. Single Vision Replacement Lenses Having the same focal power throughout the lens from top to bottom, single vision lenses can help correct a number of eye disorders including nearsightedness, farsightedness, and astigmatism. Bifocal Replacement Lenses Bifocal lenses are divided into two sections with different focal powers to correct for distance and near vision deficiencies.
Who uses bifocal replacement lenses? Progressive Replacement Lenses Progressive lenses , often referred to as no-line bi-trifocals, eliminate the visible demarcations lines of traditional bifocals and trifocals lenses. Choosing the Lens Material Replacement lenses are made from several different types of materials: plastic, polycarbonate, hi-index, or glass. What is the significance of the refractive index of a lens material? High Index Lens Information When you find eyeglasses lens index more than 1.
Choosing Additional Options for Your Replacement Lens After choosing a lens type single, bifocal, trifocal, progressive and lens material glass, standard plastic, polycarbonate, Trivex hi-index plastic , you now have several options to consider for your replacement lenses to make them more durable and comfortable to wear.
Our knowledgeable customer service representatives are here to help. Perfect Lenses — Guaranteed! High Quality — Guaranteed! Two-Year — Warranteed! What Are They? How Are They Made? A great quality piece of plastic or glass. A good optician getting the right pupil distance and segment height from your face. A great lens laboratory customizing a great piece of material to your personal needs. If you have a good doctor and optician, we take care of the other two.
A Great Piece Of Plastic or Glass Crystal Vision Lenses sm are designed by retail optical industry people who are passing on to you an important secret: Great lenses are made by Essilor, Zeiss, Pentax, Seiko, and others but they cost more when their brand names are attached to the lenses.
Lens Laboratory Craftsmen A great piece of plastic or glass is worthless if not carved perfectly by an experienced craftsman. A Lens For Every Situation Crystal Vision Lenses sm represent a diverse portfolio of lenses for every purpose, and almost any prescription. Eyeglass Lens Replacement Replacing your eyeglass lenses with the same prescription, or a new prescription, is easy to do.
Eyeglass Lenses Replacement — Types We offer all kinds of replacement lenses, including single vision, progressive, bifocal, trifocal, Varilux, and Transitions replacement lenses. Single Vision Lenses Single vision lenses are the most common lenses, both for new eyeglass frames and for eyeglass lenses replacement, although in the last 20 years with the advent of progressive lenses, single vision lenses have lost some of their popularity. Single Vision, Plastic Lenses Plastic lenses offer the best optics compared to higher index lenses, and only glass lenses have a better visual acuity.
Single Vision, Trivex Lenses Trivex is a relatively new material in the lens market, and it serves a good purpose for some situations. Single Vision, Glass Lenses Crystal Vision glass lenses offer the finest clarity of any glass lens on the market today.
Progressive Lenses Progressive lenses were invented about 20 years ago by Essilor, the worlds leading lens making company, and the creator of Crizal. Progressive Plastic Lenses Plastic lenses offer the best optics compared to higher index lenses, and only glass lenses have a better visual acuity. Progressive Polycarbonate Lenses Crystal Vision progressive polycarbonate lenses have an index of 1.
Progressive Trivex Lenses Trivex is a relatively new material in the progressive lens market, and it serves a good purpose for some situations. Progressive Glass Lenses Crystal Vision progressive glass lenses offer the finest clarity of any glass lens on the market today. Bifocal Lenses Bifocal lenses offer two viewing areas for distance and reading purposes. Bifocal Plastic Lenses Bifocal plastic lenses offer the best optics compared to higher index lenses, and only glass lenses have a better visual acuity.
Bifocal Polycarbonate Lenses Crystal Vision bifocal polycarbonate lenses have an index of 1. Bifocal Trivex Lenses Trivex is a relatively new material in the progressive lens market, and it serves a good purpose for some situations. Bifocal Glass Lenses Crystal Vision bifocal glass lenses offer the finest clarity of any glass lens on the market today. Eyeglass Lenses Coatings and Options Eyeglass lens coatings and options are all dependent on the base lens that you choose, and to a lesser extent, the frame style.
Eyeglass lenses surfacing machines. Polishing machine for glasses lenses. Eyeglass Lenses Scratch Coating Furnace. Dweller Inconspicuous Supporter. I dont know anything about them but was able to find a few places selling them when I did a search on google.
Website www. It's probably manufactured by a different company and resold as a 'crystal vision'. Low quality, paid too much or something similar? Thanks Jadin and Dweller.
I paid more than double what the product costs. The only item I couldn't find anywhere, even Wolff Cameras, was the crystal vision lens I bought. I also wanted to find out about the company to see if it is reputable or not. Learned big from this one. Gia58 said:. Click to expand KmH In memoriam Supporting Member.
Since this thread was started, and died in , tell us what year your wife had her experience with "World Camera". Joined Sep 9, Messages 0 Reaction score 2, Please examine the attached photo. Despite the fact that the original post was from , I found this information very helpful, as I just purchased the same lens manufactured under a different name.
I even found it online, too. Luckily I didn't pay anywhere close to that, but I was able to find the lens sold under the various names and the prices they are selling for. I feel better now about my purchase. Thank you for leaving these threads online, even though they are older posts. And I appreciate what was mentioned about the credit card. I will keep an eye on that for sure. You must log in or register to reply here.
Astounding scientific test. The 0. The wide angle lens widens the angle of view by multiplying the focal length of the camera lens by 0.
This more than doubles the angle of view making it an excellent lens for group shots or architecture. Improve the image composition of scenic views, and interior shots, especially when movement is restricted. The lens is supplied with a macro attachment that will allow for unsurpassed close up photography. This Professional 0. These elements are housed in an all-titanium barrel that will stand up to years of use.
Why buy from us? We are proud to offer the outstanding service and quality state-of-the-art products that our customers have come to depend on.
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