How to buy old flowers scientifically?
Lao Hua’s eye is a physiological phenomenon, and it is a visual problem that people naturally appear after entering middle and elderly people. At present, there are many categories on the market on the market, and the prices are different. Middle -aged and elderly consumers are often “dazzling” when they buy. How to scientifically buy old flower mirrors?
A few days ago, the Guangdong Consumer Council announced the comparative test results of 20 old flower mirrors. The results showed that among the 20 samples, the hometown month, the sunset red, the laugch, the laugch, the Ya Kun, the Yupintang, and the century -old red have excellent comprehensive performance, and were rated for five stars; There are 3 samples in comprehensive performance and received Samsung; 5 samples are not marked with the optical level distance (pupil distance) key information (pupil distance) according to national standards.
This comparison test involves a total of 20 old flower mirror samples, all of which are products with high attention and brand awareness of consumers. The staff simulates the actual consumption of ordinary consumers. Through online e -commerce platforms (JD.com, Tmall, Vipshop, Suning Tesco) and offline brand glasses chain shops are purchased. The uniformly purchased categories are old -fashioned mirrors (that is, the finished old flower mirror that has been prepared directly). The buying brand involves AOJO, LOHO glasses life, sunset red, old man, hometown month, etc.
Test nine indicators in the optical requirements, chemical safety, physical performance and logo of the sample test.
The top focus is that the popular saying is “the degree of the glasses”. The top of the spherical mirror is the degree of myopia or hyperopia. The top focus deviation is to check whether the number of glasses is consistent with the number of glasses. The smaller the top focus deviation, the more accurate the degree; the deviation exceeds the allowable deviation, which will cause the wearer’s vision to be corrected or over -corrected, cause incomplete regulatory function, prolong the time of regulating response, and cause visual fatigue. Long -term wear will make the eyes itself itself. Decreased regulatory ability and severely damaged the vision of the wearer.
In terms of the accuracy of the number of glasses, after testing, the top focus deviation of the 20 old flower mirror samples meets the requirements of national standard GB/T 13511.3-2019. Among them, the top focus of Chuangguo and Bai Da is the most accurate and the smallest deviations; the degree deviation of the Yupin Hall and the Holy Eagle is relatively large.
It can be seen that the transmission ratio of the spectral range is higher than 80%, and the lens has better light transmission performance. It can be seen that the spectral range transmission ratio is to assess the transparent rate of light (wavelength range in 380nm to 780nm). The larger the transmission ratio of the visible spectrum of the optical lenses, the higher the light transmission rate of the lens, and the clearer the visual item of the wearing mirror; otherwise, the smaller the transmission ratio of the visible spectrum of the lens, the lower the light transmission rate The visual clarity of the person.
In terms of the sharpness of the lens, after testing, the visible spectral scope of the 20 old flower mirror samples meets the requirements of the national standard GB 10810.3 and the industry standard QB/T2506-2017. It can be seen from the value that the light transmission ratio of 20 brands is greater than 80%, reaching the ideal visual clarity. Among them, the old flower mirror light transmission ratio of Chuangguo, Yupin Hall, and Loho glasses lives the highest among various brands, that is, the visual definition of glasses is the best; Essence
The horizontal deviation of the 15 old flower mirror sample optical centers and the vertical difference between the optical center meet the requirements of national standards. Five old flower mirror samples have not marked the optical level distance value. When the human eye is faced with peace and peace, the distance between the center of the two pupils is called the pupil distance. A pair of glasses consist of two optical lenses. The distance between the optical center of optical lenses is roughly equal to the distance between the two pupils. At this time, people are comfortable when they look at things. The optical center deviation is that the distance between the two -lens optical center does not match the distance between the human eye and the pupil, and the deviation occurs. The lens optical center shifts, and the external objects are shifted when the visual objects are shifted. The optical center of the eyes is inconsistent. The double image will cause the eye muscles to lose balance, the consequences of visual fatigue, strabismus, and eyeball.
In terms of the distance deviation of the optical optical center (that is, the pupil distance deviation), after testing, among the 20 old flower mirror samples, the 5 samples of Loho glasses life, Chuangguo, FoneX, old man, Mr. Putian brand The value cannot be obtained; the horizontal deviations of the remaining 15 sample optical centers and the vertical difference between the optical center of the optical center meet the requirements of the national standard GB/T 13511.3-2019. The results of the optical center of the optical center of the comprehensive glasses and the vertical mutual difference test results of the optical center. It can be seen that the lack of the old flowers of the sunset and Bai Shitong has the least deviation and the most accurate workmanship.
In terms of chemical safety, the nickel analysis of the 20 old flower mirror sample frames is in the scope of safety. Among them, the Saint Eagle and Bai Shitong detected 0.37 μg/(CM2 · week) and 0.28 μg/(cm2 · week). The standard limit value of more than 0.5 μg/(cm2 · week); the remaining 18 samples were not detected.
Nickel is a heavy metal element that is likely to cause skin contact. When contacting the human body, nickel ions can penetrate into the skin through pores and sebaceous glands, causing skin allergies and inflammation. The clinical manifestations are dermatitis and eczema. The nickel analysis of mirror frames is to check whether the glasses rack contains nickel or whether the nickel is excessive. Excessive nickel analysis of the glasses rack will cause human health to be damaged.
Twenty old flower mirror samples have passed 500 test fatigue tests. Fatigue resistance test as an important indicator of the durability of the glasses rack, comprehensively test the hardness, flexibility, and sustainable use of the glasses rack to ensure that the glasses products will not be bent in the daily use process. , Squeezing, etc., which are easily damaged and fractured and permanent deformation, have good durability characteristics.
Fatigue testing In accordance with the relevant requirements of GB/T 14214-2003, the mirror frame equipped with a lens after 500 testes after the fatigue test, no cracks and broken marks, the permanent deformation is not greater than 5mm, and can easily open and close with finger force. The mirror legs and mirror legs are not closed down by any point in the process of opening/closed.
In terms of durability, 20 old flower mirror samples have passed 500 test fatigue tests to meet the requirements of the national standard GB/T 14214.
In addition to the function of the old flower mirror frame, it is used as a supporting of the lens to form the human eyes to play a bracket. It also has beauty and decorative effects. Of course, in addition to the beautiful and generous and novel styles, the frame must also consider durability and have a certain degree of firmness. The binding force of the plating layer is the firmness of the assembly grid of the frame.
Glasses racks often come into contact with human sweat during wearing. The metal material on the mirror frame has been rusty and peeled by sweat for a long time, which seriously affects the appearance and service life of the product. Therefore performance.
In terms of coordination force and anti -sweat corrosion, 20 old flower mirror samples have reached the requirements of the national standard GB/T 14214, and no coating shedding breaks occur.
It is worth noting that although the 20 old flower mirror samples meet the relevant standards in the above indicators, in terms of “logo logo”, the test found that 13 samples are not in line with national standards. Marking irregularities and other issues.
Among them, the five samples of Loho glasses life, Chuanguo, FoneX, old man, and Mr. Putian’s MR.Putian brand have not been labeled at the key information of optical level distance (pupil distance). Consumers cannot choose the glasses that suits them according to the marking parameters.
Source: Consumer Report Comprehensive Guangdong Consumer Council