Views: 0 Author: Site Editor Publish Time: 2024-10-21 Origin: Site
"Is there a difference between 300 yuan and 3000 yuan glasses?" The main reason why people are concerned about this topic is probably that they are worried that improper glasses will cause damage to their eyes.
Let's start with the conclusion: cheap glasses are not necessarily a problem, but irrational glasses can indeed damage the eyes.
Therefore, the key to the problem is not the price of glasses, but whether the glasses are properly fitted, whether the choice of glasses is suitable, the choice of glasses can not only match the prescription, if the glasses are not properly matched, the impact on the eyes is long-term and far-reaching, not only may aggravate myopia, and may even induce other eye diseases.
In this article, I will talk to you about what we need to pay attention to in the process of dispensing glasses, what are the risks if we do not have proper glasses, and how can we avoid these risks as much as possible.
The most common problem with optometry is that the adjustment is not sufficiently relaxed when accommodating spasticity, resulting in a high degree of myopia. Generally speaking, after a good period of rest or no longer using the eyes for a long time with high-intensity near eyesight, the myopia will return to the original true level, but if you wear inappropriate lenses (such as over-corrected lenses) for a long time, you have adapted to the use of glasses in the state of stress, and the ciliary muscle tension has been abnormally adapted, it is easy to turn pseudomyopia into true myopia, or lead to the increase of myopia.
Improper correction of farsightedness, such as insufficient power, is easy to induce esotropia and near-eye fatigue;
Improper astigmatism correction, such as insufficient power or incorrect astigmatism axis, can lead to a decrease in visual quality.
In some cases, the accurate optometry power is not necessarily the best prescription, and our prescription parameters also need to comprehensively consider the wearer's adaptability, the difference between the original lens and the original lens (if you have worn glasses before), eye position (whether there is strabismus), visual function (adjustment, collection ability), eye habits, etc., to make appropriate adjustments to the prescription to finally determine the most suitable prescription for wearing.
When wearing glasses, the eye is required to see from the optical center of the lens, which requires our optometrists to be accurate when measuring the pupil height and interpupillary distance, if the interpupillary distance and height of the eye are not accurate, it will cause the optical center of the lens to be inconsistent with the visual axis in the horizontal or vertical direction, which may cause strabismus in severe cases.
For myopia lenses:
If the interpupillary distance is too large, exotropia is likely to occur;
If the interpupillary distance is too small, it is easy to have an internal scum.
If the lenses are fitted with one side high and the other side low, or if the frame is deformed and the height of the eyes is inconsistent, it may lead to abnormal vertical eye position and even habitual tilting of the head to look at things.
The average yellow person has a forward tilt between 8° and 10°.
If the forward angle of the frame is too large, the actual optical power generated will be greater than the power of the lens design, resulting in overcorrection and problems such as eye fatigue.
At the same time, the cylindrical effect caused by the tilt of the lens will "flatten" what you see, and the higher the power of the lens, the more severe this deformation will be.
The main reason for the excessive camber angle is the mismatch between the frame and the bridge of the nose.
If the bridge of the nose is small or flat, the support point of the oversized frame is not very stable, which can cause the lens to tilt forward. In addition, temples that are too loose or too tight can also cause the lenses to tilt forward.
The mirror angle is generally between 170-180°. Excessive mirror angles can cause a vertical astigmatism effect, which will affect the visual quality. Some frames with a novel and trendy design may not fit the facial features and cause discomfort to wear, although they look good.
If the distance between the eyes is too small, the lens may come into contact with the eyelashes, which may apply oil to the inside of the lens or damage the lens;
If the distance between the eyes is too large, the actual optical effect will not match the power of the lens, affecting the visual effect.
Sometimes, due to deformation or improper assembly of the temples, one side of the lens is close to the eyeball, and the other lens is far from the eyeball, which causes visual blur, distortion and eye fatigue.
Choosing adjustable nose pads instead of one-piece ones can solve a large part of the problem of spectacular distance in the eye.
Sometimes, due to unreasonable processing technology or assembly, the lens is deformed, which will cause additional aberrations, and even lead to ghosting, making the wearer feel dizzy and uncomfortable.
Different brands of lenses have different dispersion coefficients, refractive indexes, and coatings.
If the lens is severely worn, the light transmittance of the lens will decrease, and the vision will become darker;
If the lens dispersion is large, the image quality will be affected, which may lead to blurred vision or rainbow streaks.
Although high refractive index lenses can make lenses thinner, they are often accompanied by lower Abbe numbers or more severe dispersion, but some manufacturers have also introduced lens materials with both high refractive index and lower dispersion to provide thinner lenses with clearer visual effects.
What's worse is that because the human eye has a certain ability to adapt, sometimes the discomfort of wearing is quickly adapted, so the damage to visual health caused by the inappropriate prescription or glasses is silent and long-term.
To sum up, whether it is 300 yuan or 3000 yuan lenses are not enough to represent professionalism, if you want to wear a pair of glasses that can see "clearly, durably and comfortably", it is recommended to go to a formal medical institution for a comprehensive examination, first of all, you need accurate and appropriate glasses parameters, and then you can choose a pair that suits you based on your own needs and psychological expectations.
