When Shakespeare’s King Lear calls on “cataracts” to spout during his “Blow winds, and crack your cheeks!” speech, he’s not asking for cloudy vision.
In Shakespeare’s day, a “cataract” also meant a huge waterfall.
This is fitting, because the clouds of white foam arising from a waterfall are metaphorically like the cloudy vision caused by a cataract.
Roughly half of everyone who lives to age 80 will eventually get cataracts in one or both eyes.
Live to age 95, like the great San Francisco poet and City Lights bookstore owner Lawrence Ferlinghetti, born March 14, 1919, and you’ll have close to a 100-percent chance of getting cataracts. But that’s a small price to pay for such awesome longevity.
What exactly is a cataract? To answer that question, let’s begin by looking at the eye.
A cataract is a clouding of the eye’s lens. On the picture, do you see where the lens is in the eye? Yes, right behind the pupil.
Light enters the eye through the pupil. As the picture shows, the lens focuses light onto the retina, which is a layer of light-sensitive cells at the back of the eye.
The lens must be clear to focus light onto the retina. If the lens has become cloudy with a cataract, the image you see will be blurry.
People say that having a cataract is like looking through a dirty car windshield.
Now let’s look at how cataracts form.
The eye’s lens is composed of two substances. The first is water.
The second is protein.
As we age, some of the protein that constitutes the eye’s lens (along with water) can clump together, causing the clouding of the lens.
Although most cataracts are simply a product of aging, there are other causes of cataracts, too.
Diabetics can develop cataracts.
So can steroid users.
Cataracts can develop after an eye injury, sometimes years later.
Sometimes babies can be born with cataracts.
Cataracts can develop after exposure to radiation.
Other factors that could cause cataracts include those common bugaboos smoking and drinking.
Here are the symptoms of cataracts, in case you think you might have one.
Cloudy or blurry vision.
Colors look faded.
Glare from headlights, lamps or sunlight bother you more than it used to. You may also see halos around lights.
Other symptoms could include double vision or multiple images in one eye.
Frequent changes in your prescription for eyeglasses or contact lenses could also be a sign of cataracts. If you notice any of these symptoms, or if you are age 60 or older, ask your eye doctor to check your eyes for cataracts, as well as for age-related macular degeneration, glaucoma, or any other vision issues during your next eye exam, which should be soon.
If you do have a cataract, and it’s interfering with your normal, everyday activities, such as driving, reading, or watching TV, your cloudy lens can be surgically removed and replaced with a clear, artificial lens.
If you need cataract surgery in both eyes, usually the doctor will do each eye a month or two apart.
However, surgery should be avoided unless it’s absolutely necessary for your vision, or if a cataract interferes with getting another eye issue treated, such as age-related macular degeneration or diabetic retinopathy.
Nevertheless, cataract removal is one of the most common operations performed in the United States, and about 90 percent of people who have cataracts removed have improved vision.
Now if you don’t have cataracts and you want to forestall getting them, there are some precautions you can take, according to research done by staffers of the Mayo Clinic.
Get regular eye exams, at least once every two years, or more frequently if you notice changes in your vision.
Quit smoking and drinking alcohol.
Yeah, we know. We selected the picture. More power to her.
We like this old joke, “If I’d known I was going to live this long, I’d have taken better care of myself.” But in reality, most smokers and drinkers won’t live to 100.
Wear sunglasses and clear glasses with 100% Ultraviolet (UV) protection.
Maintain a healthy weight.
Eat plenty of fresh fruits and vegetables.
The latter finding is buttressed by research performed at the University of Oxford, the results of which were published in 2011 in the American Journal of Clinical Nutrition.
The study found that the risk of getting cataracts was greatest for high meat eaters (those who ate more than 3.5 ounces of meat each day). It decreased from each dietary group to the next, in this order: moderate meat eaters, low meat eaters, fish eaters (people who eat fish but no other meat), vegetarians, and vegans. In fact, the risk for vegans was roughly 40 percent lower than for the high meat eaters.
As addressed in this Zenni blog post on Nutrition and Vision, dark green leafy vegetables such as spinach and kale, both of which contain the antioxidant-carotenoids lutein and zeaxanthin, are associated with significantly lower risks of cataracts.
So, quit smoking, decrease or eliminate drinking alcohol, decrease or eliminate eating meat, increase eating fruits and veggies, and you might live long enough to have your first cataract as a 95th birthday present – among other goodies!
Tuesday, April, 1 2014 by Matthew Surrence
You’re just days away from what can be a fun holiday. Here are a few of the most popular April Fool’s Day pranks people play. We don’t want anybody in Zenni glasses failing to see these jokes coming.
The best April Fool’s Day pranks in history have come from television stations and other media outlets. They succeeded in convincing the public of ridiculous things like the existence of Swiss Spaghetti trees or that Taco Bell purchased the Liberty Bell. Some people suggest much more malicious pranks, but the best April Fool’s Day jokes to play just trick a person into believing something that is obviously silly.
Shrink wrap the office – This one has been done countless times, and wrapping paper or aluminum foil works just as well. Benign prankers wrap everything in an office, from the chair to the computer mouse to the pens in the desk, with shrink wrap so that working is still possible, just aggravating.
Unpaid tickets and bills – There are a number of variations on this one, from printing up a fake parking ticket that they put on your car’s windshield to using similar tools to convince you that you have unpaid bills. That feeling of panic that you’re overdue and going to owe late fees is never fun.
Everything’s gone – All a person has to do to make you think you’ve lost all your important computer files is move them to an obscure directory, make them un-discoverable by the operating systems’ search, and delete recent file data. If you sit down to a computer that seems like it’s been wiped clean of your memories, you may have been a victim of this one.
I’m blind – Popularized by the comedy show The Simpsons, this simple prank involves taping a person’s eye shut while they sleep so when they wake up in the morning they can’t see. It’s doubtful you’ll actually think you’ve gone blind, but if you usually spring out of bet at the sound of your alarm, you’ll certainly be surprised.
You’re late – Changing all the clocks in a home or office to be two hours fast so you feel late is easy. The hard part is they have to get to your watch and smart phone. Once they manage that and your alarm goes off early, you’ll be sure you’re late.
I’m (going) blind(er) – In homes where two people use different prescription contacts, the person with the weaker prescription can swap their contacts in for the other’s. When the person worse vision fumbles their contacts in in the morning, they feel like their vision has gotten dramatically worse over night. If this happens to you, be sure you don’t try to drive before sorting it out!
April Fool’s Day jokes look a lot better after the fact when you can laugh at your own behavior. But if you’re seeing clearly with your Zenni glasses, maybe you can avoid being the fool this year.
Friday, March, 28 2014 by Dave Schreiner
Everybody knows you can get reading glasses at the dollar store for a dollar.
Yes, there are exactly 99 pennies in this picture. We know because we counted. How fitting that the 99₵ store is where the couple known as Speidi (remember them?) appears to have ended up.
Because the $6.95 reading glasses you can get from Zenni are more than seven times better than the reading glasses you can get from the dollar or 99₵ store.
A lot more.
Buying reading glasses at the dollar or 99₵ store might be penny wise.
Your exact pupillary distance (PD).
Download this PD ruler if the eye doctor or optician won’t give it to you, and you can measure it yourself.
Your exact frame size.
Anti-reflective (AR) coating.
OK, if you get AR coating, they’re going to cost a little more, but it’ll be worth it. AR coating greatly reduces glare from external light sources as well as reducing eyestrain from long sessions on a computer.
See The Zenni Blog to read the AR coating blog post (“Don’t Fear Mothra – Her Eyes Inspired Your Glasses’ Anti-Reflective Coating”) for a fuller discussion of the benefits of AR coating.
A 10% pink tint on the lenses will help reduce eyestrain, too.
Now let’s break down all these categories – prescription, PD, frame size, AR coating, and tint – and examine how getting a pair of reading glasses made to order at Zenni is better in all of these respects than buying a pair at the drug, dollar, or 99₵ store.
Get outta here, you two! Your 15 minutes of fame were up 20 minutes ago.
You can’t enter your exact prescription in the reading glasses you buy off the shelf. They will have the same magnification in each lens. But most people have different prescriptions for each eye. Again:
See how the OD (right eye) has +3.00 and the OS (left eye) has +2.75? You won’t be able to customize off-the-shelf glasses accordingly, unless you buy a +3.00 pair and a +2.75 pair, and switch the lenses yourself, assuming that you can get the lens out of one frame and into the other, and make it stay there without breaking a lens or the frame.
At Zenni, you can enter your exact magnification for each eye.
In addition, your prescription may call for an astigmatism correction (that’s when the prescription has Cylinder and Axis numbers).
You won’t be able to get this on a pair of drug, dollar, or 99₵ store readers, because those eyeglasses don’t have astigmatism corrections. Consequently, everything you see will be blurry, either a little or a lot, depending on your astigmatism.
At Zenni, you can enter your exact Cylinder and Axis numbers to correct your astigmatism.
Your pupillary distance (PD) is crucial when ordering prescription eyewear, including reading magnification eyeglasses.
That’s pupillary distance, not puppy-lary distance!
The PD is the measurement from the center of one pupil to the other. The PD determines where the optical center should be placed on each lens. The reading-vision optical center should be right in front of your pupils when you read.
But your PD won’t be accommodated by a pair of off-the-shelf reading glasses. You won’t even know what the PD is, because there’s no indication of the PD on reading glasses you get at the drug, dollar, or 99₵ store.
The reading glasses you get off the shelf will have an average PD on the lenses, based on the size of the frame.
If you’re looking through a pair of reading glasses that has a wider or narrower PD than yours, it will hamper your ability to see well with the glasses. You may get headaches and eyestrain, too.
At Zenni, you select a frame that accommodates your PD. When we make the glasses, we use your PD to determine the placement of the optical center on each lens, giving you the clearest, crispest vision.
The comedian Alan King had a saying about the difference between what the English call “bespoke” (custom-made) suits and those that are purchased off the rack.
King would say, “If it’s off the neck, it’s off the rack.”
The same principle applies with eyeglass frames. You take your chances with frames you pull off the rack at the drug, dollar, or 99₵ store. You may not find one in a style you like, or one that fits you well.
At Zenni, you can select a frame in the size – not to mention style – that suits you.
AR (anti-reflective) coating:
Store-bought reading glasses don’t have AR coating. Glasses at Zenni do. It’s a great extra to order for reading or computer glasses, because it reduces glare. Again, everything you need to know about AR coating is right here.
You’re not going to find reading glasses at the drug, dollar, or 99₵ store that have a 10% pink tint on the lenses. If you’re going to spend a lot of time reading on a computer screen, this tint percentage and color would be a good feature to have, since it’s restful and helps reduce eyestrain. It’s just $4.95 at Zenni.
This completes our examination of the relative merits of store-bought reading glasses and Zenni-bought reading glasses.
Let’s review. Store-bought reading glasses don’t have your exact prescription, PD, frame size, AR coating, and 10% pink tint.
Zenni glasses do. Not much of a contest, is it? It’s hard to build suspense when the results are so lopsided, but … the envelope, please:
You, with a pair of customized Zenni reading glasses that include your prescription, PD, frame size, AR coating, and 10% pink tint. Best of all, these two won’t be in line ahead of you.
Tuesday, March, 25 2014 by Matt Souza
Yesterday, Thursday March 20, was the Spring Equinox. If you weren’t already dusting off your coolest specs and considering a new pair of glasses, now is clearly the time. From frozen to thaw to a perfectly decent day, the Equinox gave most of the East a reprieve from this brutal winter.
If you were out watching everyone enjoy the warmth, you probably saw a lot of people sporting bright, shiny glasses, glowing with the desire for spring to start in earnest.
How does the not-so-subtle beginning of spring draw people outside and lead them to don brighter colors and sometimes even a lighter step?
It’s difficult to articulate explicitly, but you know the feeling well. That mix of energy, excitement, and enthusiasm about all the possibilities now that going outside is fun again can’t be ignored.
It’s kinda like the feeling you get when you try on a new pair of shoes or glasses and they fit perfectly, matching not just the size and shape of your face (or feet), but also matching you.
The Equinox marks the moment twice a year when the Sun is directly over the Equator, and thus when the Earth’s tilt begins its transition to the coming season’s position. In the case of spring, the Earth’s axis is tilting so that the Sun will be over the Northern Hemisphere, bringing on warmer seasons.
Ancient peoples celebrated the equinoxes and solstices (there are two of each every year), often using stone “calendars” that had Indiana Jones type effects for that one day a year when the Sun is in the right position.
We might not have the benefit of unique stone temples designed to harness the equinox Sun perfectly to point out the correct door to enter the forbidden temple and find the treasure. But that doesn’t mean city streets don’t change magically when the Sun starts to come out.
Don’t believe me? I think there’s a show tune that explains it pretty convincingly. Why wait to see if the Sun’ll come out… tomorrow. With an exciting new pair of Zenni glasses and the Spring Equinox behind us, today is probably the perfect day to get outside and enjoy that burst of energy.
Friday, March, 21 2014 by Dave Schreiner
If you like the way the anti-reflective (AR) coating on your eyeglasses reduces glare, you can thank Mothra – or a real-life moth – for that.
That’s because moths’ eyes are covered with a special film that eliminates reflections. This is necessary because of their well-known attraction to flames.
No, not that kind of flame! This kind:
If moths’ eyes reflected light, it would alert predators to their presence. But moths’ eyes are coated with a super-thin film structured in a hexagonal pattern of bumps that are so tiny they are smaller than the wavelength of visible light. These bumps reduce reflections from flames or other light sources by matching the wavelength of visible light, which blocks the light’s reflections.
AR coatings on eyeglasses take their cue from the eyes of moths. They work in a similar way, using a super-thin layer of metal oxide to reduce reflection by matching a reflected wave of light with an equal and opposite “incident wave” (roughly oversimplified, an interfering wave), which causes the two waves to cancel each other out.
You don’t have to be a scientist, or even an accomplished graph reader, to see that the red wave of the reflection is equally matched by the black incident wave of the AR coating, which blocks the reflection on the lens as effectively as Jerry Kramer blocked Jethro Pugh in the Ice Bowl. (What? Ask a football fan or Google it.)
AR coatings are highly recommended for eyeglasses. They’re especially useful with high-index prescription lenses, because high-index lenses are thinner, lighter, and flatter than standard- and mid-index lenses, and therefore tend to reflect more light than lower index lenses do.
But all lenses, even non-prescription lenses, benefit from AR coating, especially sunglasses.
However, one of the most important uses of AR coating will not involve sunglasses, unless you’re this guy.
For most people, who, unlike Corey Hart, don’t wear their sunglasses at night, AR coating is a must-have for driving glasses, prescription or non-prescription sunglasses, or clear prescription lenses. AR coating is great for reducing glare from streetlights, stoplights, taillights, and oncoming headlights. It’s especially good at decreasing the “halo” effect.
Wait, not that halo effect – that one should only be increased! Multiplied, even, at every possible opportunity. Here is the halo effect you want to reduce:
AR coating has daytime and indoor uses, too. It’s great for people who spend a lot of time on the computer, since it reduces glare from the monitor, which can cause eyestrain.
AR coating performs a great cosmetic function, too. It greatly decreases the reflection on eyeglasses’ lenses from external indoor and outdoor light sources. With AR coating, people looking at you while you’re wearing glasses will see your eyes rather than what’s reflected on the lenses. This is an excellent feature to have, unless you’re acting in Alfred Hitchcock’s Strangers on a Train.
If you haven’t seen that movie, check it out. It’s one of Hitchcock’s best.
In a minute we’re going to examine the three main types of AR coatings available for eyeglasses’ lenses: standard, hydrophobic, and oleophobic. They all work the same way, by blocking reflection and reducing glare with one or more layers of metal oxide that (remember the moth) allow more light to pass through the lens.
But first, let’s dispose of the most common misconception about AR coatings: that they tint the lens. This is not true. AR coatings are clear and colorless and invisible on the lens.
But there is a color-based way to tell if your lenses have AR coating. Sometimes people will think that, because reflections on the lenses are not entirely eliminated, their glasses don’t have AR coating, even though they ordered it.
To see if your eyeglasses have AR coating, hold the glasses parallel to the ground, with the temple arms (the stems that go behind your ear) up or down. Angle the glasses so you can see reflections on the lenses. If the reflections look green or purple, your lenses have AR coating.
Here’s why: The reflections will look green or purple, or both green and purple, because AR coating blocks waves that are in the green-to-purple wavelength of the spectrum of visible light. That’s why these colors are reflected on the lenses. If that’s not confusing enough, here’s a chart that will really have you scratching your head, unless you’re an optics geek:
Now that your brain has recovered (we hope), let’s look at those three main types of AR coatings: standard, hydrophobic, and oleophobic. Standard AR coating, which is $4.95 at Zenni Optical, and which can cost north of $100 at other optical retailers, does a great job of reducing reflections on eyeglasses lenses.
But there’s a big difference between standard AR coating and hydrophobic, which is $8.95 at Zenni, and oleophobic, which is $14.95 at Zenni. These AR coatings can cost as much as $200 at other optical retailers.
The hydrophobic AR coating is called that because although it blocks reflections the same way the standard AR coating does, it’s also water (hydro) resistant (phobic). It puts a slick surface on the lens that resists the buildup of water-based moisture, which is important to have when you’re watching a tearjerker like The Best Man Holiday for the 87th time.
The hydrophobic and oleophobic AR coatings make your eyeglasses’ lenses easier to clean than lenses with the standard AR coating. You can do this experiment yourself. If you have a pair of glasses with standard AR coating and a pair with hydrophobic or oleophobic AR coating, clean each pair with the cloth that comes with your Zenni glasses. It’s much easier to clean the hydrophobic or oleophobic pair than the standard pair, right? The cloth slides right across the surface of the hydrophobic- or oleophobic-coated lenses, while on the pair with the standard AR coating there’s a little drag on the lens.
Stop it! Behave. It’s not that kind of flame and not that kind of drag.
The oleophobic AR coating is called that because in addition to resisting water the way the hydrophobic AR coating does, it also resists oil and grease (that’s the “oleo” part, as in “oleomargarine,” which is what margarine used to be called).
The oleophobic AR coating has a slick surface on the lens that, like the hydrophobic AR coating, resists the buildup of water moisture on the lens and makes the lenses easier to clean than lenses with the standard AR coating.
But it also protects against smudging from fingerprints as well as facial oils. This is useful when you don’t want to use your superpowers to clean your glasses, which would give away your secret identity.
Zenni also offers special mirror-finish oleophobic AR coatings for sunglasses. These come in gold, silver, and blue, and each is $19.95. The back of the lens has the AR coating, and the front of the lens has the reflective mirror-finish coating. The gold mirror finish looks great with frames that are gold, red, brown, or tortoiseshell, such as frame A10102114.
The silver mirror finish looks great with any frame color or style, especially A10102412.
The blue mirror finish looks great with silver, black, gray, blue, or gold frames, such as 521814, and is especially good at reflecting harmful blue light.
Or check out this beauty in the blue mirror finish. The frame (A10161222) looks great, too.
Speaking of reflecting harmful blue light, soon we’ll be launching our newest AR coating, which is specially designed to block blue light. Keep checking the Zenni Blog – and website – for details!
Friday, March, 14 2014 by Matt Souza
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