What it is
Light is a collection of electromagnetic waves. Each wave oscillates in its own direction.
When a ray of light hits a reflective surface, it is refracted and polarized. This means that some light waves vibrate in the vertical plane, while others vibrate in the horizontal plane.
After refraction, light waves oscillate in two planes: horizontal (red) and vertical (blue)
The vertical component of light allows a person to obtain information about the world around him (to recognize objects, their shape, color, etc.). Horizontal reflection causes glare, glare, interference, etc.
To suppress the horizontal component, special polarizer filters are used that transmit only those waves that oscillate in the vertical plane.
Polarized glasses use exactly these filters. They are a thin liquid crystal film placed between layers of plastic or glass. The molecules in this film are arranged in a strictly vertical direction. Gaps are formed between them, which transmit light waves with vertical oscillation.
Only those waves that oscillate in the vertical plane can pass through vertical gaps
The difference between polarized glasses and anti-glare glasses
Since polarized glasses reduce glare reflected from a smooth surface, many people assume that the term “anti-glare” applies to glasses. But this is not true at all.
Anti-reflective coating is applied to the lenses of glasses for vision correction. It makes the lenses more transparent, which increases their light transmission and reduces reflection from the surface of the lenses themselves. That is, when you look at a person wearing glasses, you clearly see his eyes, and not a reflection of himself or surrounding objects.
The interlocutor's eyes are visible through the anti-reflective lens
People wearing glasses with anti-reflective coating note that contrast and clarity of perception improve.
Who needs polarized glasses?
Polarized glasses can be called simply a godsend for those people who, due to the nature of their activities, often encounter reflected blinding light. These glasses help:
- to all road users (motorists, cyclists, etc.), when bright rays are reflected from wet asphalt and “hit” the eyes, which increases the likelihood of an accident;
- those who spend a lot of time on the water (fishermen, drivers of motorized watercraft, etc.). Anyone who has been near bodies of water has seen how the surface of the water reflects sunlight, which completely blinds a person (especially when the sun is above the horizon at an angle of 30–60°);
- athletes: marathon participants, biathletes, skiers, cyclists, rowers, speed skaters and others. Optical interference created by reflected rays can significantly reduce athletic performance;
- cleaners of external windows of high-rise buildings. The sun's rays give a powerful reflection from a smooth glass surface (especially if it is mirrored), which can create a certain danger during work and reduce the quality of washing;
- lovers of sea and mountain resorts. It should be recognized that such glasses help to significantly improve the quality of rest.
Polarized glasses increase contrast and image quality while blocking glare
Features of polarized glasses
Lenses for polarizing optical systems are made using a special technology that allows them to neutralize the harmful effects of reflected light on the eyes. Polarized lenses have three layers. The middle one is represented by a transparent film, and the outer ones are tinted glass. The film acts as a kind of grating that allows only the vertical part of the light beam to pass through and blocks the horizontal part.
The glasses in polarized glasses are covered with a film that contains liquid crystal particles, the molecules of which are oriented in one direction. Due to the strong magnetic field, gaps (optical axes) are formed between the molecules. Neutralization of polarized light occurs at the moment when the microslits are parallel to the reflecting surface.
Polarized lenses reduce the negative impact of reflected light on the eyes by 50%. With additional darkening (tinted windows), this figure can be increased.
Advantages and disadvantages
Regular sunglasses merely reduce excess sunlight through the use of darkening materials. Their light transmission is 15–20%. However, the intensity of the reflected (polarized) light is much higher, and ordinary sun glasses are not able to cope with it.
Therefore, polarized glasses in this situation have a number of advantages over sun lenses:
- reduction of visual tension and, accordingly, eye fatigue;
- improvement of visual perception, which helps many people to fully carry out their professional activities;
- neutralization of the negative effects of ultraviolet radiation. Sunglasses are not all capable of blocking UV rays.
However, polarized glasses also have certain disadvantages:
- high price. Their average cost is 3,000 rubles;
- reduced readability of traffic signs because glasses block reflected light;
- difficulty viewing information on a liquid crystal screen (tablet, GPS navigator, phone with an LCD screen).
Some consumers complain that they experience headaches when using polarized glasses. This is only possible in the following cases:
- a counterfeit was purchased, during the manufacture of which the direction of the polarization axes was violated;
- frame too small. If the temples of the glasses compress the temples, blood circulation is impaired, which can cause the development of headaches.
How to choose
To avoid disappointment after purchasing polarized glasses, you should choose them wisely. In this case, you need to be guided by certain criteria:
- Purpose of purchase. You need to clearly understand where and under what conditions the accessory will be used. Accordingly, it is necessary to take into account the degree of darkness of the lenses, as well as their color.
- Comfort. When purchasing glasses, you need to carefully consider the shape of the lenses and frames. When putting on glasses, you should smile broadly: if the lower edge of the lenses does not come into contact with the skin, then there will be no discomfort when wearing glasses. The frame should not be too narrow or wide. With a small frame, there will be high pressure on the temples, and with a large frame, the glasses will not hold well and fall.
- Manufacturer. It is recommended to choose models from trusted brands. Otherwise, you may stumble upon a low-quality product.
- Model. Since polarized glasses are not only functional, but also a stylish accessory, it is important when purchasing them to consider the shape of the lenses, frames, colors, etc. In addition, glasses can be men's, women's and unisex.
- Additional features. In certain cases, in addition to the basic criteria for choosing glasses, some particulars are of great importance. For example, for fishermen, it is important that the glasses do not drown if they accidentally fall into the water. Therefore, it is better for them to choose models equipped with special inserts that prevent the glasses from sinking.
Video: How avid fishermen choose polarized sunglasses
How to choose the right polarized lenses
You won't be able to buy polarized glasses that are suitable for different occasions and conditions. When choosing anti-reflective lenses, it is recommended to listen to the advice of experts:
- When choosing lenses, you should start with their color. For example, motorists are advised to choose two color options. Copper or brown polarized sunglasses are ideal for daytime driving. Many users have already proven that these colors provide special benefits: image contrast is reduced, as a result, the eye muscles relax. Lenses with a cinnamon tint absorb UV rays better than others. For driving in the evening, a different model is required. Yellow lenses are ideal for this purpose;
- It's easier for fishermen. For their purposes, one model of glasses is suitable. Gray lenses will do the job perfectly. They are especially suitable for those who like to fish in deep water. On a clear, hot afternoon for fishing, it is better to wear glasses with green lenses.
Where is the best place to buy
It is recommended to purchase polarized glasses in the manufacturer's branded stores or in trusted retail chains and opticians. They can also be purchased from reputable online stores, but in this case the consumer does not have the opportunity to try on the glasses before purchasing and feel how comfortable they are.
In addition, retail outlets offer the opportunity to check glasses for the degree of polarization.
To do this, take two pairs of polarized glasses and place their glasses perpendicular to each other . With 100% polarization, nothing will be visible through two glasses.
The lower the degree of polarization, the more light will penetrate through two crossed lenses.
There is another way to check whether your glasses are polarized or not. To do this, the glasses should be pointed at the LCD screen of the monitor. When the lens is rotated 90°, the image through it will darken or disappear altogether.
When should you order glasses individually?
Polarized glasses are ordered individually when they must perform two functions at once: muffle glare and correct vision. In this case, the ophthalmologist examines the patient's vision and then writes a prescription for lenses. In optics, polarized glasses with certain diopters are made.
Review of leading manufacturers
By purchasing polarized glasses from reputable brands, you can be confident in the quality of the product.
Polaroid (Japan)
Polaroid is the most famous brand that was one of the first to produce polarized glasses.
The company name Polaroid has become a household name for all polarized glasses. Quite often you can hear such glasses called “Polaroid”.
The lenses in Polaroid polarized glasses consist of 7 layers. The middle one is a directly polarizing light filter. On both sides of it there are layers that neutralize ultraviolet radiation. Next, buffer elements are attached, which ensure the lightness and flexibility of the lenses. The last layers are a hard coating that gives the lenses strength, reliability and durability.
Polaroid glasses provide 100% protection against glare and UV rays.
Average price - 2000–3000 rubles.
The Polaroid company is responsible for the quality of its products, therefore each product is accompanied by a passport
Cafa France (Taiwan)
The manufacturer Cafa France carefully approaches the selection of materials and the manufacturing process of the product. It also uses multilayer lens production technology.
Cafa France glasses have a high level of polarization and ultraviolet protection.
Models from this manufacturer are most popular among drivers, since the lenses are made of lightweight and heavy-duty plastic. In the event of an accident, the glasses remain intact and do not injure the driver’s eyes.
The price for Cafa France glasses ranges from 1200–2700 rubles.
Polarized glasses have their own passport, which indicates the high quality of the product
Shimano (Japan)
Japanese manufacturer Shimano presents a wide range of polarized glasses. The lenses use a complex structure of light filters, while the lenses themselves have a minimum thickness, which ensures comfortable wearing of glasses.
Shimano offers glasses with additional features: floating, ultra-light frames, glasses with replaceable lenses, with adjustable nose pads, with side wind pads, etc.
Shimano sunglasses have a polarization rate of 99% and UV transmission of 0.1%.
The cost of glasses of the average category is 2500–3500 rubles.
In the presented model, you can change the lenses to yellow ones, which allows you to use polarized glasses in bright weather and on cloudy days
Salmo (China)
Salmo polarized glasses are in great demand among fishermen. It should be noted that the company itself specializes in the production of fishing products. Among its assortment, polarized glasses also appeared, which are very popular among other consumers.
Goggles provide high eye protection from reflected light from the surface of water, snow, and ice. The models are characterized by lightness and durability, so they can be worn without taking them off for several hours.
The average price for glasses from Salmo is pleasantly surprising - 600–1000 rubles.
This model of glasses from Shimano protects from side winds and does not allow the glasses to sink due to the presence of foam rubber on the inside
Cafa France
Cafa France brand glasses can be put on the same level as Polaroid - the same attention to the technical nuances of production, a large selection of models, both women's and men's, and an affordable price (from $25). There are eight layers in Cafa France lenses, that is, only one less than Polaroid. They are distinguished by a high polarization index and 100% protection against UV radiation. Cafa France also has glasses with yellow lenses that increase contrast, which is very convenient, for example, at night or in snowfall. Cafa France has proven itself to be the ideal glasses for car enthusiasts. Not only due to the high quality of polarization and a clear picture, which improves visibility on the roads, but also due to special plastic lenses that will not break in the event of an accident and will keep the driver’s eyes and face intact.
