When ordering on our e-commerce, in some cases, the question arises whether the sunglasses I see on the web are what I'm looking for. There is a way IDENTIFY UNEQUIVOCALLY of glasses you or optical tests on a specialized trade, the spectacle of a friend, a goggle that you have, etc...
All sunglasses AUTHENTIC, BRAND, enter their identification within one of its legs. This identification is not always the same structure, although always specified pattern, the color of the frame and the color of the lens. In some brands is incorporated first alphabetical code of two or three letters that identifies the brand. Can also be incorporated in the same size, but are exceptional glasses sold in various sizes. Also, recently, some manufacturers are including removal filter light or sunscreen.
ALL OUR REFERENCES have the same structure, to make it easier to choose the glasses you are looking for.
Below we show a graphical example, as the information is organized inside a lug of a sunglass either:
In any case, please contact us with any questions you have regarding the glasses you are looking for.
The sight is probably one of the most precious human senses and may be the best way to integrate the outside world in our consciousness. A slight alteration of any of the complex structures of the eye is enough for the influence to this sense. Ophthalmologists has always talked about the dangerous of sunlight for the sight health.
That is why sunglasses must be chosen not only for fashion reasons, but you must also take into account sunlight protection criteria.
- Altitude. At higher elevations, there is less atmosphere to protect us and therefore more radiation. 1,000 meters above sea level, increases the intensity of radiation by 10%.
- Latitude. The closer to the equator, the greater danger.
- Ozone Layer. The hole in the ozone layer, especially near the South Pole, increases the risk in the Antarctic regions, despite their distance from the equator. The WHO predicts that in the coming years there will be an increase in the number of cases of cataracts and other visual diseases as a result of the reduction in the ozone layer. At present cataracts cause more than 17 million cases of blindness annually.
- Season of the year. In the northern hemisphere the month of June and July are the most dangerous. In the south, the biggest risk is in December and January.
- Time. Between 10 AM and 2 PM there is the greatest concentration of radiation.
- Clouds. Clouds do not protect us, as they let 90% of ultraviolet radiation through. It is a mistake to think that we can dispense with sunglasses on a summer day just because it is cloudy and the light bothers us less.
- Environment. Radiation increases by 20% on sand, 30% on water and 90% on snow, due to reflection factor of these surfaces.
- Dangerous behaviour. Falling asleep on the beach (even with sunglasses), observing the sun (without special glasses), observing phenomena such as eclipses or undertaking industrial work such as welding without glasses.
- Age. Children’s eyes are especially vulnerable to the sun as they do not finish forming until 18 years of age. Therefore they should always wear appropriate protection.
- Eye type. Light eyes have less natural protection.
The use of sunglasses WITHOUT AN OFFICIAL WARRANTY. The degree of darkness of a pair of sunglasses is not an indication of their level of protection, as very dark lenses do not adequately absorb ultraviolet radiation. In this case, it is more harmful than beneficial, since these lenses force our eyes to use less visible light, thus reducing our natural defence mechanisms against the light (pupil contraction). For this reason, it is worse to use sunglasses with poor sun protection.
Studies by the Spanish National College of Opticians Optometrists discovered that between 70% - 80% of sunglasses that are sold in Spain, are not guaranteed as OPTICA.
Optical glasses unsecured, usually purchased in flea markets, bazaars or stalls, lack the necessary filters to prevent the passage of ultraviolet radiation (UV) light to our eyes. This has serious consequences for our health, some of them:
- Intense headache
- Eye fatigue
- Abnormal photophobia (intolerance to light)
- Kerato conjunctivitis Radiation
- Ulcers epithelial
- Corneal degenerations
- Macular Edema
- Retinal degeneration
Moreover we must take into account that the effects of ultraviolet (UV) radiation are cumulative, so the reaction of our body will be worse as more radiation is received.
Filter Ultraviolet Protection (UVB). All sunglasses must provide a 100% protection to this type of radiation.
Filter sunscreen. The percentage of light they let through the lenses of the glasses. It is important to choose according to the ambient light, the tasks and our sensitivity to glare. Below is a table in applications as filters and restrictions, according to European standard EN 1836:2006: No Transmission Name Apply Filter Restrictions.
|0||80% - 100%||Clear or slightly stained lenses||Interiors / Sky||No|
|1||43% - 80%||Slightly stained Lenses Luminosity||Solar light||Night Driving|
|2||18% - 43%||Moderately stained Lenses||Medium Brightness solar||Night Driving|
|3||8% - 18%||Strongly stained Lenses||Strong solar luminosity||Night Driving|
|4||3% - 8%||Dark lenses|
Extreme solar (Sea or Mountain)
- * The above EUROPEAN STANDARD EN 1836:2006, which provides 5 levels ranging from less to more protection, from 0 to 4. To ensure that the glasses fit this rule, it is important to require that the glasses exhibit the CE mark.
- * The AUSTRALIAN STANDARD AS 1067 also provides 5 levels of protection, ranging from 0 to 4.
- * The U.S. Standard ANSI Z80.3-2001 does not distinguish between different levels of protection. Requires a transmittance of UVB (280 to 315nm) and UVA (315 to 380nm) does not exceed 1% and 50% respectively of the transmittance in the visible range.
The colour of the lens. The lens colour is not an indicator of protection to solar radiation and will be selected based on the needs of each user or on aesthetic preferences
Some colours offer more contrast than others, or allow a perception of colours more accurately.
According to the latter we can consider the following classification:
LITTLE OR NO DISTORTION IN THE COLOUR
Gray lenses are considered neutral because it does not alter either the contrast or colour.
Green or brown lenses. May cause minimal distortion of the colour and increase contrast.
HIGH OR MEDIA DISTORTION OF THE COLORS
Red lenses. Good conditions for medium or low light, because they increase the contrast.
Orange and yellow lenses are best to increase the contrast in the perception of depth on cloudy or foggy days.
Blue or purple lenses. No real benefits.
Lens types. According to its nature or composition can be divided into:
Mineral. Commonly called "crystal", offer greater scratch resistance and optical clarity. * Body or polycarbonate. Commonly called "plastic", the most common compound is called polycarbonate CR-39, present in many of the current lens sunglasses (although there are other compounds), offer a lighter weight and greater impact resistance. Polarization. It is a treatment that the lenses of sunglasses can undergo, and is used to avoid glare caused by light reflection on surfaces such as water, snow, sand, glass, metal, asphalt, etc.. Anti-reflective treatment. Incidental light can be reflected from the rear on the inside of the lens and can be annoying. To avoid this, antireflective treatments can be applied on the inside.
Mirrored Lenses. Mirrored lenses reflect light to prevent it from going into the eye. It is an "extra" filter that can be added to other filters. It is achieved by adding a thin reflective layer to the outer face of the lens. The principal problem is that it can spider or scratch easily.
Graded lenses. The top of the lens is dark, avoiding sky glare and the bottom is clear, in order to help the wearer focus.
Photochromic lenses.These lenses darken automatically based on the amount of light they receive.
Shape. This depends on the use we want to give our glasses and on our facial morphology i.e. fashion sunglasses or sports sunglasses. For example, for sports activities in environments with very high brightness levels, or other adverse weather conditions, it is advisable to use closed glasses that suit the coverage of our face. In this way our eyes are protected completely from indirect sunlight and increased protection is obtained from environmental hazards such as dust.
All sunglasses sold in Europe have to comply with European Directive EN1836: 1997, which indicates that they have to offer a 100% protection against ultraviolet radiation. While it is true that this rule does not define what is meant by a 100% UV protection. SPANISH LEGISLATION "Real Decreto 1992". In 1992 the Spanish government through a Royal Decree regulated the safety standards to be followed by sunglasses manufacturers. Highlighting the importance of having a high degree of protection against ultraviolet rays, no rough edges, and optical neutrality.
We must be especially careful with our sunglasses. Some basic rules to ensure their care:
- * When not in use they must kept separate from other objects.
- * They should be washed with water and / or mild soap, and left to dry naturally and then cleaned with a lens cloth.
- * We can use specific products, but must satisfy ourselves that there is no dust or sand on the lenses so as not to scratch them.
- * Do not leave them in direct exposure to sunlight, for example on the car dashboard, or other enclosed spaces in which high temperatures can be reached and this deform the lens mounts.