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Why 3D Movies Sometimes Fall Flat

Why 3D Movies Sometimes Fall Flat

The first three-dimensional movies came out in the 1950s, and over the past 60 years they have continually risen and fallen in popularity. With the success of Avatar in 2009, it looked like 3D would become the default for mainstream film. While 2D remains popular, many modern movies offer a 3D option, either because they were filmed specifically in 3D or were edited in post-production.

Seeing a film in 3D gives the viewer an enhanced experience, as you completely immerse yourself in the world on the screen. However, for some people, the effect is less than thrilling. Some people purchase the 3D ticket, put on the glasses, and spend the next two hours watching a flat, unfocused, two-dimensional movie, while possibly suffering from nausea or headaches.

If you can’t see movies in 3D, you aren’t alone. Around 12 percent of the population struggles with depth perception, also known as stereoblindness. For this segment of the population, 3D movies are nothing special.

Many people with stereoblindness don’t recognize the condition, since they have never seen the world in any other way. However, as you walk out of a 3D screening with your friends feeling underwhelmed, you may want to know why you see differently, how it affects your perception of the world, and if there’s anything you can do about it.

What is Stereoblindness?

Human eyes are set up so that each eye perceives a slightly different image.  The disparities between the two images are processed by the brain to provide depth perception, which allows people to gauge distances and how objects relate to each other in space.

Those with stereoblindness have eyes that are either dysfunctional or misaligned. For example, if you have a lazy eye or are cross-eyed, your eyes struggle to focus in the same direction, meaning that your brain is receiving different pictures entirely, instead of the same image perceived from two different angles.

How Does Stereoblindness Affect Your View of the World?

Those who were born with stereoblindness likely don’t realize that they see the world differently from others with stereo vision. Your mind learns to adapt to make sense of the world around you as best it can, and you can still perform most daily tasks, including driving a car in some cases, without a problem.

However, there are certain situations where lacking depth perception can be a problem. Many people with stereoblindness confess to being bad at sports that require an ability to properly see distances, such as tennis or basketball. They may also have difficultly pouring liquids into a glass or threading needles, and they likely can’t become a pilot or surgeon because these jobs require strong depth perception.

Of course, the most readily noticeable side effect of stereoblindness is the inability to see 3D movies, games, or pictures.

How Do 3D Films Work?

Three-dimensional films work by tricking your eyes into thinking they’re staring at an object with depth, not a flat screen. Movies filmed in 3D are usually shot by two cameras, placed at about the same distance apart as human eyes. The two images are then superimposed on each other, mimicking the process of stereo vision in the brain.

If you look at a 3D film, or other form of media, without any additional instruments, the image looks flat and blurry, which is why you need a pair of 3D glasses. Older 3D films relied on color systems to achieve the 3D effect. One camera would have a blue filter, and the other a red filter, and the audience would receive a pair of 3D glasses with one blue lens and one red lens. The different colors mimic the image disparity of looking at real-world objects, which creates a sense of depth.

Modern 3D entertainment relies on polarization, not color. One lens of the polarized glasses views vertical light waves, while the other views horizontal light waves.  Again, the image disparity between the right eye and light eye mimics real vision, making the flat image on the screen appear to have depth.

If you have stereoblindness, you can’t see the slight image disparity in the first place, so putting on the glasses simply brings the movie into focus, while remaining flat.

Can You Cure Stereoblindness?

The possibility of treatment depends on what causes your stereoblindness, how long you’ve had it, and how severe it is. Children born with lazy eyes or crossed eyes can receive surgery to strengthen the muscles and hopefully bring the eyes back into alignment, but this doesn’t always work, and probably won’t help adults who have been stereoblind for years.

There isn’t one solid technique used to treat stereoblindness, nor do experts have a way to predict with 100 percent certainty that a technique would work. Some doctors recommend surgery, regardless of age, while others find vision therapy helpful. Neuroscientist Susan Barry, who had been stereoblind her whole life, practiced eye exercises to train herself to see depth and successfully developed stereo vision.

For at least one person, psychology professor Bruce Bridgeman, watching a 3D movie actually corrected his stereoblindness. It’s not a scientifically proven cure, and might not even work for another person, but it might give you a good reason to go to the newest 3D movie with your friends—just in case.

If you’re comfortable with your current sight, it’s possible to live a complete and fulfilling life without striving for stereo vision. However, if you want to try and understand what all this 3D hype is about, visit All About Eyes for a comprehensive eye exam and some expert advice.

Understanding the Different Parts of Your Eye

Understanding the Different Parts of Your Eye

You know that your eyes allow you to see and that several different factors affect good or poor eye health. But what else do you know about your eyes? Do you know what parts comprise this amazing organ or how they aid in vision?

Below, we discuss the different parts of the eye, as well as what issues can affect some of these components and therefore impact your ocular health.

Anterior Chamber

The anterior chamber rests behind your cornea but in front of your lens and iris. It holds the aqueous humor and allows it to drain properly from your eyes into your bloodstream.

Aqueous Humor

This thick fluid rests in the anterior chamber and provides nutrients to these two parts of your eyes. The liquid must drain regularly, and your body replaces it.

However, if you develop glaucoma, this fluid will build up, creating an uncomfortable pressure in your eyes.

Choroid

This small, vascular layer sits between your eye’s sclera and retina. It provides the outer layers of the retina with nourishment (through blood vessels) and oxygen. While you won’t develop health issues in the choroid, this component refracts light, causing the red-eye effect in photos.

Ciliary Body

The ciliary body sits between your choroid and iris, and it produces the aqueous humor and holds the lens in place.

Conjunctiva

This clear membrane covers the white portion of your eye, or the sclera. The conjunctiva also covers the inside of your eyelids. It produces mucus and tears to lubricate your eyes and keeps microbes out of your eyes.

If this thin membrane becomes inflamed or swollen, you likely have conjunctivitis, commonly known as pink eye. Other eye conditions that affect the conjunctiva include pinguecula, pterygium, and subconjunctival hemorrhages.

Cornea

Your cornea is a clear covering that rests over your pupil, iris, and anterior chamber. It provides most of your eye’s optical power. The cornea refracts light and helps your eyes focus on objects in your line of sight.

Eye issues that relate to your cornea include astigmatism, corneal abrasions, keratitis, keratoconus, and pterygium.

Fovea

The fovea is a small depression in your retina that contains cones to aid in proper eyesight. If you have problems with the fovea or the cones in it, you could develop blurry vision.

Iris

The iris is the colored portion of your eye. It is made up of a fibrovascular tissue called the stroma. The stroma connects to a muscle that allows your pupils to contract and dilate.

Developing a disease in the iris is rare, but you could still contract some conditions that affect your eye’s intraocular pressure, and, indirectly, your vision.

Lens

This part of your eye is a transparent structure inside your eye. It’s about the shape of a lentil, and it can curve both inward and outward. Like the cornea, your lens refracts light. The lens is held in place by a fibrous membrane called the zonule of Zinn or the suspensory ligaments of the lens.

If the lens has an irregular curve to it, then you’re likely to develop astigmatism. Another vision condition involving the lens is cataracts, where the lens becomes opaque or cloudy and impairs vision.

Macula

This part of your eye is close to the center of your retina. The macula allows you to see objects in great detail. As you age, you could develop macular degeneration, a disease that can cause vision problems or lead to vision loss.

Optic Nerve

This nerve carries electrical impulses from the rods and cones in the retina to the visual cortex in your brain. Without the optic nerve, your other eye components cannot send images to your brain and produce your sense of sight.

Pupil

Your pupil is the black circle in the center of your iris. It regulates how much light enters your eye. Interestingly, the pupil appears black because this tissue absorbs most of the light that passes through it.

Retina

Your retina is a sensory membrane that covers the entire back surface of your eye. When your lens picks up images, these images are sent to the retina. The retina then changes these images into signals that the optic nerve then pulses to your brain.

Some ocular issues that affect the retina include diabetic retinopathy, retinal detachment, retinitis pigmentosa, and retinoblastoma.

Sclera

The sclera is more commonly known as the whites of your eyes. This fibrous layer contains collagen and protects the inner components of your eye from damage.

Trabecular Meshwork

This component is located at the base of your cornea. It drains the aqueous humor from your eye through the anterior chamber. Using tubes known as Schlemm’s canal, the trabecular meshwork lets fluid drain into your blood system.

If the trabecular meshwork can’t properly drain the aqueous humor, you could be at risk for glaucoma.

Vitreous Humor

This transparent, gelatinous material sits between your lens and retina. It also lines the back of your eye. The vitreous humor contains cells called phagocytes that remove debris from your eye so you don’t develop eye infections.

 

Now that you understand more about what parts comprise your eye and how the organ functions as a whole, you can take more measures to protect your eyesight. If you have problems seeing or experience any other issues with your eyes, get in touch with an eye doctor from All About Eyes.

Work at a Computer All Day? Take Care of Your Eyes

Work at a Computer All Day? Take Care of Your Eyes

If you work in front of a computer all day, you may notice that your eyes get tired, dry, or itchy. Staring at a screen for hours at a time can take a toll on your sight. You may worry that you’re permanently damaging your eyes, or you might wonder what you can do to deal with the discomfort.

If you’d like to know more about the relationship between your eyes and your computer, keep reading. You’ll learn how screens affect your vision and your health and what you can do about it.

Computer Screens and Your Eyes

If your work involves heavy computer use, you may notice eye trouble. You’re not alone—at least 50 percent of those who work in front of a computer report eye issues, but the number may be closer to 90 percent. You may notice symptoms like:

  • Blurry vision
  • Dry, itchy, or red eyes
  • Double vision
  • Headaches

None of these symptoms are fun, and if they’re severe enough, the quality of your work may suffer. These symptoms are often called computer vision syndrome. Like carpal tunnel syndrome, the condition is caused by repetitive use: your eyes work hard to keep reading on a computer screen, and they get tired.

Just reading from a page for a long time can be hard for your eyes, with all the eye movement and close-up focus the task requires, and computers make the problem worse. The glare, flickers, and screen contrast on a computer screen require even more from your vision.

Additionally, when using computers, many people forget to blink. Usually we blink around 15 to 20 times per minute, but when reading a screen, we often blink only half that amount. All of that staring can dry out your eyes, which contributes to the irritation.

However, rest assured that you are probably not doing your eyes permanent damage. While computer vision syndrome may be unpleasant, if you take some time off from the computer, your eyes will get the rest they need and start feeling better again.

Computer Screens, Your Eyes, and Your Sleep Habits

Viewing computer screens for hours can affect more than your eyes. Most screens are backlit with blue light, which can interfere with your sleep cycle. A Boston, Massachusetts group of researchers at Brigham and Women’s Hospital did a study on the effects of reading on a tablet before bedtime versus reading a printed book before bed.

The group that read on a backlit device took ten minutes longer to fall asleep and didn’t sleep as deeply as the group that read printed pages. The researchers believe that the blue wavelengths electronic screens emit interfere with the production of melatonin, a sleep-promoting hormone. Consequently, those using screens don’t feel sleepy, so they stay up late and have trouble when they finally go to bed.

If you stay up late using a tablet or a computer, and then you don’t sleep well, you’ll only be contributing to your eyes’ dryness, strain, and discomfort, along with the other adverse effects of sleep deprivation.

Healthy Eye Habits

If your eyes are struggling, you’ll need to make some changes. The most obvious change is to cut down on your screen use, especially in the hour or two before bedtime. However, if you work in front of a computer, you won’t be able to just quit your job. Try the solutions below.

Keep Your Distance

If your computer is too close to your face, your eyes will have to strain to stay focused. However, you don’t want your screen to be too far away either. Keep your monitor just below your eye level and about 20 to 28 inches away from your eyes. This is considered the optimal spot by researchers.

Get Rid of Glare

Extra glare on the computer screen makes your eyes work harder as they try to decipher the text. The biggest cause of glare is natural light coming through a window—you can either move your computer out of the light or close the blinds.

You may have extra glare if the overhead lights are too bright. See if your employer can install a dimmer switch or if you can only turn on some of the lights in the room. If nothing else, you can also get relief by using a glare filter on your computer screen.

Play With Your Settings

You may find your computer screen too bright or too dim for comfort, or maybe you have to work to read a tiny font. Just play with your settings—with a little experimentation, you may find a more comfortable option.

Take a Break

You can’t get away from your computer, but your eyes still need time off. Use the 20-20-20 rule: every 20 minutes, look away from your computer at an object about 20 feet away. Look at that object for 20 seconds. This will give your eyes a chance to reset their focus.

 

If you’re having trouble with your eyes, check your screen use. You can keep your eyes comfortable by remembering to take care of them. However, if your symptoms don’t go away, or if you need more information, contact All About Eyes to make an appointment.

What You Need to Know About Wearing Contacts in Water

What You Need to Know About Wearing Contacts in Water

By the time summer rolls around, we’re well on our way into the hottest part of the year. You love the warm air, the sunshine, and the views outside, but the heat can become more than a little unbearable.

As the temperatures begin to rise, you think of fun ways you and your family can cool off and find some respite from the ever-present heat waves—like by camping, stargazing, or swimming at the local pool.

Swimming is a fun activity, one that not only helps you feel more comfortable in the heat but that also helps you exercise more frequently. But if you wear corrective lenses of any kind, swimming can be a bit more difficult for you than for people with perfect vision.

Specifically, if you wear contact lenses, you may wonder if you can swim with them in. Below, we’ll tell you everything you need to know about swimming in contacts so you can still stay cool this summer while keeping your eyes healthy and your contact lenses in good condition.

Keep Your Contacts Away From Water

Although your contacts allow you to see perfectly during your normal, daily activities, these corrective lenses were not made for water. In fact, when you were prescribed your contact lenses, your eye doctor told you how to care for them—and those instructions likely included strict guidelines to not rinse your contacts in water.

This advice has merit for a few reasons. Water—whether it be pool water, tap water, lake water, or shower water—can house microbes, viruses, chemicals, and bacteria that could cause eye problems and irritation. If these microbes or viruses get trapped in your contacts, they remain in your eye longer. As a result, your risk for eye infections and more serious conditions increases.

For example, the Acanthamoeba organism is one microbe you could encounter in water. This organism attaches to your contacts and then causes your cornea to inflame and become infected in a condition known as Acanthamoeba keratitis. If the infection isn’t caught and treated early on, a corneal transplant is necessary to restore your vision.

Fortunately, a severe infection like Acanthamoeba keratitis isn’t a very common condition. More likely, you’ll experience a slight irritation or infection in your eyes when you’re exposed to the floaters and bacteria in water. If your eyes feel irritated or if you’re developing an infection, you might notice the following eye-related symptoms:

  • Abnormal redness
  • Blurred vision
  • Burning
  • Discharge
  • Discomfort
  • Excess tears
  • Grittiness
  • Itching
  • Pain
  • Swelling
  • Unusual sensitivity to light

If you’ve recently gone swimming and have developed these systems, make an appointment with your optometrist immediately.

Steps to Take If Your Contacts Have Been Exposed to Water

Have you recently hit the pool, the beach, or the lake? If you’ve recently taken a swim and worn your contacts while under the water and experience any the symptoms listed above, take the following steps:

  1. Remove your contacts immediately.
  2. Place your lenses in your contact case.
  3. Schedule an appointment with your optometrist.
  4. Take your contacts with you to your eye appointment.

Once you visit your eye doctor, he or she will examine your eyes, pinpoint the cause of the discomfort, and treat your condition. The sooner you can get treated, the less risk you have for developing more serious eye problems.

Ways You Can Enjoy the Water and Protect Your Eye Health

You can still enjoy summertime water activities and care for your eyes—without the risk of infection. If you plan to swim but need corrective lenses, invest in a pair of prescription goggles. You can also wear your contacts with completely closed goggles if you can’t get a prescription. Simply remove your contacts after you’ve finished, rinse them thoroughly with contact solution, wet your eyes with rewetting drops, and put your contacts back in.

If you hate the feel of goggles over your face, you can wear daily use, disposable contacts in the pool. Dispose of these lenses immediately after you’ve finished swimming, and wear glasses or a new pair of contacts for the remainder of the day. Note, however, that bacteria and microbes can still enter your eye. Wearing single-use contacts to swim doesn’t guarantee your eyes won’t get infected or irritated, but it does lower your risk.

Depend on Our Experts to Care for Your Eyes

You shouldn’t have to sacrifice good eye health for a few moments of fun in the water. Remember to keep your eyes healthy by not swimming in your contacts and by using the tips mentioned above.

If you notice any changes in your vision or if your eyes become irritated after swimming with contacts, make an appointment at the All About Eyes location nearest you. We’ll see you in a timely manner and treat any eye condition you have in the best and easiest way possible.