Ho Optometrist

Your Local Optometrist from 怡保……Ipoh….. Perak, Malaysia

How Polarized Lens Works?

Polarized lenses are used in sunglasses to reduce glare from reflective surfaces such as the surface of a lake or the hood of a car. They accomplish this feat through a process called polarization, much like a venetian blind controls sunlight through a window.

Sunlight itself is not polarized – light from the sun will either be absorbed or reflected horizontally, diagonally or vertically. The problem this causes for fishermen and drivers lies in the horizontal reflectivity. Sunlight bouncing off a horizontal surface will strike the viewer’s eyes at a similar angle. This means the glare from the surface of the water or the road or the car hood will be strong. Polarized lenses have a laminated surface containing vertical stripes. These stripes only allow vertically polarized light to enter the wearer’s eyes. Glare is eliminated because the horizontally polarized light waves cannot bypass the polarized filter.

Imagine you are standing on the shore of a calm lake in early morning. What you see is a bright, glass like mirrored surface on the water, with no detail, little contrast, and poor colour saturation. As you slip on your polarized glasses, the bright, glass like mirror is replaced with a scene that shows detail and has deep colours and good contrast. That’s what polarized lenses can do. Photographers use them to add bolder colours and deeper contrast to their photographs. The polarized lenses remove the glare and improve the visual quality of the picture, much the same way polarized ophthalmic lenses perform for the patients who wear them.

 

Polarized lenses are made from a special polarizing film that is applied in the factory on the front surface of the lens. This film allows light rays to be filtered,consequently improving the vision in strong light conditions. Polarized lenses will protect you from UV rays, glare and intense light.

In combination with a reflection-free coating, polarized lenses are ideal for fishing and driving.

Polarized Sunglasses

For years, boaters and fishermen have used polarized sunglasses to reduce glare from the water that they spend so much time on. In the past few years, however, the benefits of polarized sunglasses have been realized by a variety of other outdoor sports enthusiasts as well as by drivers and general use wearers. The popularity of polarized lenses has increased dramatically, as has availability.

Besides boaters, people who benefit most from polarized sunglasses include skiers, golfers, bikers, and joggers, who enjoy a clearer view and elimination of glare. 

These sunglasses can be used for driving and in fact can reduce the glare that comes off a long, flat surface such as the hood of the car or the surface of a road.

Polarized sunglasses can also be used indoors by light-sensitive people such as post-cataract surgery patients or by those exposed to bright light through windows.

 How Do Polarized Lenses Work?

Light reflected from surfaces like a flat road or smooth water is generally horizontally polarized. This horizontally polarized light is blocked by the vertically oriented polarizers in the lenses.

The result: a reduction in annoying and sometimes dangerous glare.
There is some debate on the effects of polarized lenses on snow-covered surfaces. Some experts say they can reduce the intense glare that is caused by sunlight reflecting off snow.

Others purport that the lenses are not satisfactory for sports such as downhill skiing because they may not provide the contrast the eye needs to distinguish ice patches or moguls.

In addition, polarized lenses may also react adversely with liquid crystal displays (LCDs) found on the dashboards of some cars or in other places such as the digital screens on automatic teller (bank) machines. The problem with LCDs is that when viewed through polarized lenses from a certain angle, they can be invisible.

However, for most other sports and activities, polarized sunglasses can offer great advantages. And today, many types of polarized lenses are available on the market.

Whether you spend your time boating or waterskiing, inline skating or mountain biking, driving or jogging, polarized sunglasses are an excellent choice.

Understanding Polarized Light and Polarized Lenses

While they enjoyed only limited use among optical professionals for many years, polarized lenses have become the first choice for anyone interested in a comfortable and attractive sun lens.

The principle of polarized light reduction is best illustrated by thinking of a polarized lens as a Venetian blind. The blind blocks light at certain angles while allowing light to transmit through selected angles. Polarizing filters are aligned 90° to the angle of the polarized light. As spectacle lenses are designed to eliminate the polarized light in the horizontal plane, the filter is placed vertically in the eyewire or eyerim. This means that the filter must be properly aligned during surfacing and edging layout, otherwise the filter will not work properly.

Tint vs. Polarized

Although darkly tinted sunglasses may reduce brightness, they do not remove glare like a polarized lens. In addition, dark sunglasses without added ultraviolet protection may

cause more damage to the patient’s eyes than not wearing sunglasses at all. The darkness of the lens can cause the pupil to dilate, letting more ultraviolet rays into the inner parts of the eye. Polarized lenses solve both problems by eliminating glare and filtering out harmful ultraviolet light because the filter reduces the polarized glare and also has ultraviolet absorbing properties.

Today’s polarized lenses represent the best sunwear and outdoor lifestyle options available. With a little explanation and demonstration on your part, your patients will enjoy the benefits of these lenses for years to come.

 

Advantages of Polarized Lenses

Features

  • Filters glare
  • Enhances contrast
  • Reduces squinting
  • Constant density tints
  • Backside AR compatibility
  • Tintable and coatable
  • Lightweight
  • Thin

Benefits

  • Reduces eyestrain, greater comfort
  • Improves visual acuity, provides safety
  • Eyes feel rested
  • Realistic perception
  • Reduces reflections and enhances visual clarity
  • Certain lens materials can be darkened and provides limitless colour options
  • Comfortable Attractive-looking sunwear
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Parents Must Know: Lazy Eye

What is Amblyopia (lazy eye)?
Amblyopia, commonly known as lazy eye, is the eye condition noted by reduced vision not correctable by glasses or contact lenses and is not due to any eye disease. The brain, for some reason, does not fully acknowledge the images seen by the amblyopic eye. This almost always affects only one eye but may manifest with reduction of vision in both eyes. It is estimated that three percent of children under six have some form of amblyopia.

Lazy Eye and Strabismus are not the same condition.
Many people make the mistake of saying that a person who has a crossed or turned eye (strabismus) has a “lazy eye,” but lazy eye (amblyopia) and strabismus are not the same condition. Some of the confusion may be due to the fact that strabismus can cause amblyopia. Amblyopia can result from a constant unilateral strabismus (i.e., either the right or left eye turns all of the time). Alternating or intermittent strabismus (an eye turn which occurs only some of the time) rarely causes amblyopia.

While a large eye turn or deviation (strabismus) is easily spotted by the layman, amblyopia without strabismus or associated with a small deviation is usually not noticed by parents or pediatricians. Only an Optometrist or Eye Doctor comfortable in examining young children and infants can detect this type of amblyopia. This is why early infant and pre-school eye examinations are so necessary.

Due to misunderstanding or misuse of the terms for different visual conditions (i.e., crossed eyes vs. lazy eye), many people are inaccurately labelled as having a “lazy eye.” If you think you or someone you know has lazy eye, it is recommended that you learn more at What is Lazy Eye? and What is Strabismus?, Learn, also, about a common related visual condition which is not detected by the standard 6/6 eye test.

To complete the picture, find out about the treatment options for amblyopia and strabismus.

Causes of Amblyopia
Both eyes must receive clear images during the critical period. Anything that interferes with clear vision in either eye during the critical period (birth to 6 years of age) can result in amblyopia (a reduction in vision not corrected by spectacles or elimination of an eye turn). The most common causes of amblyopia are constant strabismus (constant turn of one eye), anisometropia (different vision/prescriptions in each eye), and/or blockage of an eye due to trauma, droopy eyelid, etc. If one eye sees clearly and the other sees a blur, the good eye and brain will inhibit (block, suppress, ignore) the eye with the blur. Thus, amblyopia is a neurologically active process. The inhibition process (suppression) can result in a permanent decrease in the vision in that eye that cannot be corrected with glasses, lenses, or lasik surgery.

Diagnosis of Amblyopia
Since amblyopia usually occurs in one eye only, many parents and children may be unaware of the condition. Far too many parents fail to take their infants and toddlers in for an early comprehensive vision examination and many children go undiagnosed until they have their eyes examined at the Optometrist or Eye doctor’s office at a later age.

The most important diagnostic tools are the special visual acuity tests other than the standard 6/6 letter charts currently used by schools, pediatricians, Optometrist and eye doctors. Examination with cycloplegic drops can be necessary to detect this condition in the young.

Treatment of Amblyopia
Early treatment is usually simple, employing glasses, drops, Vision Therapy, and/or eye patching. While detection and correction before the age of two is considered to offer the best outcomes, recent scientific research has disproven the long held belief that children over seven years old can not be successfully treated. See a press release at National Institutes of Health — National Eye Institute.

In conclusion, improvements are possible at any age, but early detection and treatment offer the best outcome. If not detected and treated early in life, amblyopia can cause a permanent loss of vision with associated loss of stereopsis (two eyed depth perception). Better vision screenings are needed for young children. The 20/20 eye chart screening is not adequate.

SUMMARY:

  • If not detected and treated early in life, amblyopia can cause loss of vision and depth perception.
  • Recent National Eye Institute research has proven that lazy eye is successfully treated in older children. Research has not yet been done on treatment in adults.
  • Improvements in vision can be achieved at any age, but early detection and treatment still offer the best outcomes.
  • Comprehensive vision examinations are needed for infants and pre-school children. A vision screening by a pediatrician or the 20/20 eye chart screening is not adequate for the detection of amblyopia (and other visual conditions related to or mistakenly called lazy eye).
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Spot the Animals!

I found this amazing picture of Optical Illusion and would like to share it out. As you look into the picture, you will find more and more animals. Its amazing, enlarge the picture and have Fun!

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Parents Must Know: Child’s Vision

What Parents Need to Know?

Children’s vision care is essential to every child’s development. Experts say that over 80 percent of what a child learns in school is presented visually, so making sure your son or daughter has good vision can make a big difference in their academic performance.

Routine eye exams for children can detect any nearsightedness, farsightedness and/or astigmatism your child has so it can be promptly treated with eyeglasses or contact lenses. Routine exams are also needed to make sure your child’s eyes are healthy and to rule out amblyopia, strabismus and other binocular vision problems that may interfere with your child’s vision development, academic performance and sports vision.

Your Child’s Vision

It’s easy to take a child’s vision for granted. After all, young eyes are healthy eyes, right? 
Not necessarily. Look around your child’s classmate and you’ll find more and more children are wearing spectacles at younger age.

Your Child is not STUPID!

Finding out your child copied wrongly and unable to cope in class does not mean your child is less intelligent.
How can your child perform when he or she cannot see clearly?

More than half of all Malaysian children have not had a comprehensive eye exam. Not to mention going to the right expertise such as Optometrist, Paediatric Optometrist or even Opthalmologist. Many of them need spectacles and don’t even know it. And because 80% of everything children learn comes through their eyes, uncorrected vision problems impact their ability to learn and interact with the world around them.

Can vision problems really affect my child’s behavior?

Yes. In fact some vision disorders are misdiagnosed as behavioral problems such as Attention Deficit Hyperactivity Disorder (ADHD). This can result in a long and difficult process for parents and children, when the real solution may have been as simple as a trip to the Optometrist or Opthalmologist and proper vision correction.

Don’t let vision problems affect your child’s behavior and performance for the rest of his life.

My child gets vision screenings at school, isn’t that good enough?

No. Many parents believe that school vision screenings are sufficient care for their children’s eyes. But this is not true. Simple eye checks are good for detecting some common problems such as trouble seeing distance. However, they may not catch everything, including astigmatism and blurred vision, just to name a few.

How do I know if my child has a vision problem?

If your child is displaying any of the following symptoms or behaviors, you may want to take them in to an Optometrist  for a comprehensive exam:

  • Dislike or avoidance of reading
  • Short attention span
  • Poor coordination when throwing or catching a ball, copying from chalkboard, or tying their shoes
  • Placing their head close to their books or sitting close to the TV
  • Excessive blinking or eye rubbing
  • Using finger or pencil to guide eyes
  • Decreasing performance in school

Your child does not have the ability to understand or describe vision problems. Don’t leave your children’s health up to them; make sure they get a comprehensive eye exam.

How often should I take my child for their eye exam?

Optometrist do recommends that children have a comprehensive eye exam at six months, three years and five years of age. After that your child should have a comprehensive annual eye exam (or every two years, if no vision correction is required).

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How to Manage, Clean and Care your Spectacles?

How to Clean your spectacles? Why is my spectacles lens still greasy and blurry? How can i remove the scratches in my lens? These are some of the common questions we face in our daily lives of wearing spectacles. Here are some simple tips to take care of your spectacles.

Handling Spectacles:

Removing and wearing your spectacles single-handed like Tom Cruise might look so cool. But yet how cool would it be when its crooked and lob-sided when you are wearing it? 

Rules are simple, just remember to use both hands when handling your spectacles. Technically is to ensures equal pressure being disperse to the frame, so in long-term it will reduce chances of the frame being lob-sided or out of shape.

Store Spectacles Where It Should Be:

Could you imagine how much damage are you doing to your spectacles when just simply throwing it into your bag? Not to mention exposing to car keys and coins? Or just simply putting your spectacles on the table – LENS FACING DOWN?

Or letting your small kids playing with it? Or a chew snack for your house cat, with nice biting engravings on the surface of the lens? These are just some of the common cases we encounter before adjusting our customers spectacles.

Save your spectacles by storing it inside the Spectacle Case when you are not using it; Or put it somewhere safe where it’s away from harm. It will make your life less miserable when you really need your spectacles to perform.

Cleaning Spectacles:

One might ask, why should I clean my spectacles? I have got many customers that have not clean their spectacles for ages, and shockingly only come in  when service is needed for adjustment, screw tightening or when nose pads are worn off !?!

Just imagine, we wear our spectacles the most of the time compared to any other accessories such as clothing, wrist watch and earrings. After a day hard work, all the sweat, facial oil, dust from our body is washed away after a nice good shower, but do we shower our spectacles? No. So you get the picture of cleaning your spectacles?

Actually to Clean you Spectacles isn’t difficult. Just follow the few steps below and you’ll have a Well Maintained, Happy Spectacles.

 

  • Turn on your tap with running water and rinse your spectacles over it.
  • If your find your lenses are oily, just latter some NORMAL HAND SOAP for some FOAM and gently rub it over the surface of the lenses.
  • Rinse it clean.
  • Dry it with some tissue. Do not leave any water mark on the spectacles.
  • Use the special MICRO-FIBER material SPECTACLE CLOTH to wipe your spectacles dry and clean.
  • Do this few times a week and you will feel great!

Lastly, hope that these few tips and advices above could help you all to enjoy more from your spectacles.

” Take care of your Spectacles,

 and your spectacles will Take Care of You. ”

Till then, Cheers,

Deric Ho

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Now you know…… the Evolution of Spectacles.

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Charity Health Screening in Shah Alam 7th August 2011

On a bright sunny Sunday morning, while others are still tucking in their bed, my wife and i started our journey from Ipoh to Shah Alam for a charity eye screening event co-organised by the Malaysian Glaucoma Society. It was the first screening for some years since my uni days and was quite excited about it. After nearly 3 hours drive, finally found the place….. DEWAN ORANG RAMAI, TAMAN GLENMARIE.

Both of us were surprise to find that there are so many volunteers that turn up that day. Looks like the world is full of love after all. There were different booths for different types of screenings. Some Medical Doctors were there to support as well as people from the hearing department and of course the Eye screening departments.

Its a small hall, but its good enough. Organisors are busy pin pointing the directions for the residents from one booth to another for Blood Pressure checks…… Hearing tests……. Fundus checks….. VA tests…… its like a station master game.

  Well, our team of Optometrist and Optometry Students from UiTM began our screening with no time to lose as more and more residents are coming for the eye test. We set up areas for Preliminary test which includes Cover Test, Hirschberg, Ocular Motility, with VA assesment and lastly Opthalmoscopy. It was busy, but it was worth it. Everybody gave all their best in that day’s service.

 Many of the residents that turn up that day are having their first eye test in years. We manage to handled some cases while detect several cases Cataracts, and DR and referred the residents accordingly.

 

It was a very meaningful day. Met some new friends, learned loads of new things, had a great time…. what more could one asked for. Till next time then…..

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