Why are the plastic lenses of glasses more expensive than the entire DSLR? What s so expensive?

The main reason why plastic lenses are more expensive than SLR lenses is the difference between their process level and labor costs.

The difference between the two lenses. SLR lenses are mainly made by polishing glass by machines, and the clarity and impurity rate of the glass directly determine the quality of SLR lenses. Plastic lenses, on the other hand, are organic materials that are made through a complex process from raw materials extracted from petroleum.

Although glass lenses are harder than plastic lenses, they are not easily scratched during use. However, because of its high weight, it is not acceptable to more people. Glass lenses have a higher refractive index than plastic lenses, and at the same power, glass lenses are thinner than plastic lenses.

The light transmittance and mechanical and chemical properties of glass lenses are relatively good, with a constant refractive index and stable physical and chemical properties. Therefore, glass lenses are often used to make SLR lenses.

The process and cost of both lenses. The production process of plastic lenses mainly includes 12 parts, after selecting the appropriate materials, first according to different diopters for the assembly and pouring of the mold, here it is necessary to pay attention to the overflow phenomenon found in the pouring process, which needs to be treated separately, otherwise it will not be able to enter the next link. The poured mold is cured at high temperatures, and then a second curing is required to relieve internal stresses.

After curing, the semi-finished product needs to be molded to separate the mold from the lens. This is followed by a series of side-and-wash cycles. Subsequently, the lenses are manually inspected, and the unqualified lenses with scratches, broken edges, particles, bubbles and foreign objects are discarded and their hardness is tested.

Finally, the coating and inspection are carried out under vacuum. This has caused the disadvantage of complex process and high loss rate of plastic lenses, and the best way to reduce the loss rate is to improve the machine, which is a very large investment. The manufacture of glass lenses is made in batches, because of the limitations of the scope of use and the stability of the parameter structure, so the mass production of glass lenses can greatly reduce costs.

It is because the content of plastic lenses is very scarce, and the number of plastic lenses is also very small, which is why it is so expensive. The more expensive places are so rare, the quality is very good, and it is made by hand polishing.

It shows that the quality of this plastic lens is very good, and the quantity is very rare, which is why it is so expensive. The expensive part is that the quality, the way of doing it, the method of production, the process of polishing, and the quantity are scarce.

Mainly because of its complex manufacturing process, and it has a stronger protective effect on the eyes; Such lenses are wear-resistant, easy to clean, cost-effective, and can play a role in protecting eyesight.

Plastic lenses are expensive because they are a kind of pure natural plant synthesis, which is less harmful to the human body and more environmentally friendly than glass lens glasses. Consumers are also more inclined to choose plastic glasses, which are more expensive for these two reasons. I think resin glasses are better than glass glasses.

Let's take a look at this problem**, I hope these contents can help friends in need.

1. What are the characteristics of plastic lenses?

Plastic lenses are made by the reaction polymerization of diethylene glycol and propenol esters. Compared with glass lenses, plastic lenses have the characteristics of light weight, good impact resistance, high temperature resistance and good light transmittance. In addition to its own characteristics, it also takes into account the performance of glass lenses, blocks ultraviolet rays, and can also choose colors according to consumer preferences, customized according to individual needs.

Plastic lenses are softer than glass lenses, when we wear resin eyes, we should pay attention to resin lenses do not touch hard objects, when cleaning plastic lenses, we should use water to clean the dust particles on the lenses, you can also use a small amount of detergent to clean. Finally, choose to wipe it with a special glasses cloth for plastic lenses, and if the plastic lenses are still oily, you can go to the optical store to clean them thoroughly.

IIWhat are the advantages and disadvantages of plastic lenses?

The advantages of plastic lenses are: thermal expansion coefficient, thermoplasticity, shrinkage, curvature, optical transparency, water absorption, optical stability and other properties. Plastic lenses are the biggest advantage of all lenses in terms of impact resistance and weight, so they are relatively light to wear and there is no need to worry about the glasses breaking.

The disadvantages of plastic lenses are: poor abrasion resistance, easy to wear or scratch. The refractive index of ordinary plastic lenses is lower than that of glass lenses, so ordinary fiber lenses of the same power will be thicker than glass lenses. Pay attention to maintenance during wearing plastic lenses to prevent scratches.

Compared with glass lenses, plastic lenses are more durable and less prone to wear and tear. Therefore, it will be a little higher than glass lenses.

Because of the plastic lens, it is relatively light and thin, so it is relatively expensive to refine, and the glass lens is a little better than the plastic lens.

Glass lenses are optical glass, and resin lenses are an organic material. Plastic lenses are light, impact-resistant, and the visible light area is close to glass, while the invisible light area has poor light transmittance, low cost, and easy processing, compared to glass lenses.

This is some functional lenses, and the coating layer and technology used are better, so they are very expensive.

When the former rock is equipped with glasses, some lenses that are better than the excavation have more functions, which can not only prevent blue light, but also have better materials, waterproof and wear-resistant. **Also more expensive. Huiyu.

Glasses lenses are worn on people, good lenses are good for the human body, and the sleepy cover will definitely not be cheap, and his workmanship and material must be able to match his **.

Summary. In terms of production costs, glass lenses are higher than plastic lenses, and their prices are correspondingly higher.

In terms of production costs, glass lenses are higher than plastic lenses, and their prices are correspondingly higher.

Resin lens is a kind of fiber acre type lens made of organic materials, its main point is that it is relatively lightweight, and has strong impact resistance and is not easy to break; At the same time, the light transmittance of plastic lenses is very good, and the cost is relatively low. However, the surface of the plastic lens is less abrasion resistant.

The main material of glass lenses is optical glass, which has a higher refraction rate than resin cavity pants, and has more scratch-resistant characteristics than lenses made of other materials. Compared with plastic lenses, glass lenses are more wear-resistant and less prone to scratches. However, the disadvantage of glass lenses is that they are more easily broken and heavier.

The little brother can choose according to his own needs.

I wish you a happy and prosperous New Year.

First of all, let's talk about the advantages and disadvantages of resin sheets.

Advantages of resin sheet: light weight, not broken, impact resistance, low hardness, easy to be grinded.

Disadvantages of resin sheet: thicker than glass sheet of the same degree, not resistant to high temperature, low density, easy to yellow, high refractive index lens**.

Advantages of glass sheets: better light transmittance, up to more than 99%, high density, the lens is much thinner than the resin sheet of the same degree, the lens is not easy to yellowing after a long time, the service life is relatively long, cheap, the hardness is higher, and it is not suitable for grinding.

Disadvantages of glass sheets: fragile, heavier than resin sheets, if your degree is not high about 300 degrees, then glass sheets and resin sheets can be selected. It's just that the glass ones will be heavier, the lenses are fragile, and the glass ones can't be made into rimless and half-rimmed glasses, so they can only be selected in the whole frame.

If it is mixed with resin, it will be much lighter than the glass sheet, and the thickness will be slightly thicker. There is no restriction on the frame of the resin lens, and the frameless half frame and full frame can be selected.

If you have a power of more than 6, you can still choose plastic lenses, but you should choose lenses with a high refractive index, which will look thinner than ordinary resin lenses. But it's also a little bit higher. The glass one can only be equipped with a full frame, and the weight will be a little heavier.

If it is more than 1,000 degrees, then I still recommend you to use a glass sheet, because the difference between the thickness of the glass and the thickness of the resin sheet is very obvious. If you use resin sheets, you can't say that it's thick...

I don't say what lenses are good or what lenses are not, the key is to see which aspect you pay attention to. However, now that resin lenses account for more than 95% of the market, glass lenses are becoming more and more difficult to buy. Now resin sheets are already the mainstream. The days of glass are over...

In terms of material, the optical effect of glass is better than that of resin, but the glass is easy to be damaged and broken, and glass sheets have been banned in some places abroad, and the resin sheets are very lightweight, if the film is added, it can also prevent radiation, but the weakness is that it is easy to scratch, so it needs to be well maintained, and it is best to rinse it with water before wiping.

Of course, the plastic lens is better, the glass is not good, it is fragile, and it may be blind when it collides.

Here is a description of the characteristics of plastic lenses!

Optical properties of plastic lenses:

1.The surface gloss and smoothness of plastic lenses are in no way inferior to those of ordinary glass lenses.

2.The refractive index of plastic lenses is lower than that of ordinary glass lenses, so plastic lenses of the same power are thicker.

3.The dispersion of plastic lenses is very similar to that of glass lenses.

4.The see-through rate of plastic lenses is 92%, which is more than 2% higher than that of ordinary glass lenses.

5.The surface reflection of plastic lenses is lower than that of ordinary glass lenses, and they are less dazzling, which is due to their higher light transmittance and lower refractive index.

6.The bifocal lenses of plastic lenses are composed of a single piece, and are not made of fusion like ordinary glass bifocal lenses, so there is no chromatic aberration in plastic bifocal lenses.

7.The optical properties of plastic lenses are extremely stable and do not change at high or low temperatures.

Mechanical properties of plastic lenses:

1.Plastic lenses can be cast into a wide range of shapes with high transparency and optical requirements.

2.Plastic lenses are easier to frame than regular glass lenses.

3.Plastic lenses are easy to dye and can be dyed into a variety of colored lenses with different light transmittance as needed.

Physical properties of plastic lenses:

1.Plastic lenses are lightweight, and their weight is only half that of regular glass lenses.

2.Plastic lenses are particularly impact-resistant.

3.When the resin lens is shattered by impact, there are fewer fragments, and the fragmentation area is large and blunt; Minimise injuries to the eyes and face.

4.Even after long-term use, the surface of the plastic lens is not prone to breakage.

5.Plastic lenses have strong impact resistance to high-temperature, small-sized objects, and when such objects hit the plastic lenses, they will immediately bounce off; It is not like ordinary glass lenses, which can easily cause dents and spots. Therefore, when welding or using grinding wheels, plastic lenses can be used to protect the eyes from flying fire dust.

6.Because plastic lenses have low thermal conductivity, they have better anti-fogging properties than conventional lenses.

Chemical properties of plastic lenses:

1.Plastic lenses are resistant to chemicals and chemical solvents in a wide range. With the current household chemicals and chemical solvents, almost no harm will be caused to plastic lenses.

2.Plastic lenses have low thermal conductivity, and when heated, they have extremely high heat resistance, and are not prone to bending and torsion deformation at a certain high temperature.

The material selection process is different, the resin lens is a special material - made of polycarbonate, and the cost of the material is not the same, so the price of the resin lens is a little higher, and the Haoyu glass lens is wear-resistant, the lens is thin and the optical performance is good.