Here are some facts about the eyes and eyeglasses that can be of help to you in your daily life.
Myopia is very common among Japanese people, and the school health statistics provided by the Ministry of Education show that it affects 15 to 18% of elementary school students, over 20% of junior high school students, 50% of high school students, and over 60% of college students. Statistics produced upon VDT eye examinations conducted by the Japan National Society for the Prevention of Blindness show that nearly 80% of those who work with word processors or computers have myopia.
Myopia has been researched as a major issue in Japan ever since the founding of the Japanese Ophthalmological Society in 1897, but it is still unknown what causes it or why it advances. There are many theories behind its causes, but none are conclusive. There are scholars who say that myopia is a disease and there are those who say that it is not a disease, but none of their theories are yet to be proven conclusive. This has been a topic of much debate, but the prevalent theory at this time is that mild myopia is more of a functional disease (a condition where the tissues are operating abnormally) than an organic disease (a condition where the tissues change pathologically). Apart from this, there is also excessive myopia, which is accompanied by organic changes, and is the fifth cause of blindness according to a joint survey held between the Japan National Society for the Prevention of Blindness and the Ministry of Health and Welfare.
Setting aside the cause of myopia, it is highly recommended that you avoid excessive use of your eyes if you have this affliction so that it does not become advanced. It is necessary for us to avoid using our eyes for long periods of time and letting them rest these days as we now often exhaust them with computers and games.
The structure of the eyes is already complete at the time of birth. However, vision is not good. The structure of the brain is nearly complete at six years of age. This is when vision is also nearly complete. Vision improves along with the development of the brain. However, severe hyperopia, myopia, and astigmatism are signs of trouble! It means that only blurry images can be seen and that transmissions between the eyes and brain are poor. This means that vision is not developing properly. The use of devices such as eyeglasses and contact lenses are a must by the time a child reaches six years of age in such cases. It is too late if the brain has already gone through its developmental stages.
Colored lenses each have their own special roles to play in accordance with their respective colors. They should be selected not only for their appearance, but also on familiarity with their special features.
- Yellow lenses
Yellow lenses make objects appear bright and clear. They are convenient for driving on cloudy days and foggy days, as well as for activities such as skiing and hunting.
- Brown lenses
They prevent glare and cut out heat rays under the strong sunshine. Lenses with a wide range of applications that make objects appear bright even in the shade.
- Green lenses
Vision is softer as the absorptance of colors at both ends, with short-wavelength violets and long-wavelength reds, is high.
- Smoky (blue-gray) lenses
They equally absorb colors in all areas of visible radiation. They make everything look darker but at the same time make it easy to distinguish colors in bright places while controlling glare. Lenses that are friendly to the eyes.
The benefits of eyeglasses cannot be fully realized just by wearing them. Eyeglasses that have been properly adjusted and properly worn let you see clearly and do not cause fatigue. Are your eyeglasses O.K.?
Points to remember when wearing eyeglasses
- Are your frames appropriately inclined with your lenses directed at where you look?
The proper angle of inclination is 12 degrees with eyeglasses for looking at far distances and 15 degrees with those for looking at short distances.
- Is the distance between your eyes and lenses 12 mm?
- Are the centers of your eyes aligned with the centers of the lenses?
- Do you see things through the centers of your lenses?
This is particularly important with progressive multifocal lenses.
See the effects that not making proper adjustments can have.
- The inclination of the frame is not proper, the lenses are not directed at where you look, images appear blurry or distorted, and so on.
- The power of your lenses may be weaker or more intense than designed if the distance between your eyes and lenses is not 12 mm. The width of your perception also changes with this distance. The decreased width of perception when the lenses are 1 mm farther from your eyes is the equivalent of wearing one frame size smaller, and perception gets wider as the lenses get closer.
- If eyeglasses are worn slid down like pince-nez glasses, images may appear blurry or distorted because the centers of the lenses are not being used. This can cause fatigue through excess movement of the eyes as you may point your eyes downward or both eyes inward in an attempt to see better.
Progressive multifocal lenses, which let you see from both far away and close up, are very convenient because a single pair is enough for most situations in daily life. However, there are some who say that they recently experience fatigue while reading even though the power is right for them once they get used to wearing the eyeglasses. The direction of the eyes must always be downward and the range of comfortable vision becomes narrow while reading with lenses for both short and far distances. It is no wonder that we experience fatigue when reading for long periods of time.
There is always a place that is easy to see and a place that is difficult to see no matter what kind of lenses you use. Using one pair of lenses for all purposes places a tremendous burden on the eyes. Switching eyeglasses when there is a difficult place to see is a practice that is friendly to the eyes. It is a good idea to use different eyeglasses to suit your lifestyle. Using eyeglasses that make it easier to see adds more comfort to your life.
Environmental pollution that is spreading on a global scale. Destruction of the ozone layer. There is concern over the increasing amount of ultraviolet radiation that falls down on us as well as its harmful effects. Large amounts of ultraviolet radiation are extremely harmful to the eyes! It causes damage to the cornea and lens. Ultraviolet radiation damages the cornea when there is exposure to direct sunlight or reflected light at places such as ski resorts and beaches for long periods of time. Devices such as welding burners, which emit large amounts of ultraviolet radiation, can cause severe inflammations of the cornea and conjunctiva.
It is also said that ultraviolet radiation is a cause of cataract. This means that eyeglasses with ultraviolet protection are essential in this age of environmental pollution! Now, we have UV400 lenses, which cut out most of the harmful ultraviolet radiation that is out there. There are many types of lenses on the market for cutting out ultraviolet radiation such as transparent lenses. But remember that some sunglasses that are thought to provide plenty of protection from ultraviolet radiation do not provide much protection at all!
Hay fever has suddenly become a growing problem in recent years. It is particularly common in early spring and causes sneezing, runny nose, and other bothersome symptoms such as itching and teary eyes! We see many people who dread the coming of spring. Hay fever affects people who are allergic to pollen such as that from cedar trees, orchard grass, ragweed, and wormwood, which are mainly dispersed from February to April. Remember that there is more pollen such as that from cedar trees when the summer of the previous year is particularly hot!
Pollen causes allergic conjunctivitis when it affects the eyes and produces various symptoms such as sinus conditions in the nose and bronchial asthma in the respiratory tract. Symptoms caused by orchard grass are considered to be particularly severe. Avoiding the causes of allergies is the best way to prevent them. However, it is impossible to avoid pollen completely as it is found everywhere we go. It is recommended that you see a physician such as an ophthalmologist and take the best medication that is prescribed to you.