There are many kinds of glass, optical glass is one of them, it is able to change the direction of light propagation. It is widely used in optical instruments, such as lenses, prism, etc.. Optical glass, it must meet the requirements of the light, it is not more than the general glass, the quality of the optical glass is also very high. Qualified optical glass it needs to meet the following requirements.

First of all, optical constants of optical glass and optical constants of the same batch of glass should be the same, the first type optical glass of different wavelengths of light have the provisions of the standard index of refraction, as a basis for optical designers in the design of optical system.

So the optical constants of factories for the production of optical glass must be in the numerical values of certain allowable deviation range within, otherwise it will make the actual as design quality and expected results inconsistent and affect the quality of optical instruments. At the same time, because the same batch of instruments are often used in the same batch of optical glass manufacturing, in order to facilitate the uniform calibration of the instrument, the deviation of the refractive index of the same batch of glass is more strict than their standard deviation.

Secondly, it needs to have a high degree of transparency, the brightness of the optical system into the image and the transparency of the glass into a proportional relationship. Optical glass to a certain wavelength of light transparency in the light absorption coefficient K. Light passes through a series of lenses and lenses, whose energy is partially absorbed by the interface of the optical part and the other part is absorbed by the medium (glass). The former with glass refraction rate increases, the high refractive rate of glass this value is very large, such as the heavy flint glass surface optical reflection loss of about 6%.

The stripe of common glass, mainly because of the material is not uniform; refractory material corrosion (mainly introduces Al); the stirring of the production of glass products produced.

So optical glass from the several aspects, the raw material requirements of >99% purity, impurities are less than one hundred thousand minutes, and the size of the raw materials, the scale has a high demand. Take the pot or platinum as refractory ceramics. In general, the casting method, the rolling method, the broken cylinder method and the liquid method are used to prevent the stirring of the glass in the forming process.

Also furnace structure and daily-use glass furnace is not the same, it is melting pool (feeding), regulation pool (adjust the melting atmosphere), refining pool (clear), equalization basin (mixing), large furnace Nissan amount is generally only 5 tons.

Optical glass is a kind of inorganic material, which is used to transmit light through the refraction, reflection, transmission, or change the intensity or spectral distribution of light through the absorption. Stable optical properties and high optical uniformity.

Today, you can explain some kinds of optical glass according to the optical properties:

1, colorless optical glass. The optical constants have specific requirements, with the visible area of high transmittance, no choice of absorption and color characteristics. Abbe number size according to the crown and flint glass, all kings and according to the refraction rate level is divided into several kinds and according to the refraction rate size are arranged in order. Used as a telescope, microscope, camera, lens, prism, mirror, etc..

2, anti radiation optical glass. Larger absorption capacity, high lead glass and CaO-B2O2 system glass on high energy irradiation, the former can prevent the gamma ray and X-ray radiation, which can be slow neutron and thermal neutron absorption, mainly used as the shielding and peeped through the window materials in nuclear industry, medical field, and so on.

3, colored optical glass. Filter glass. Ultraviolet, visible and infrared region specific wavelength selective absorption and permeation, according to the spectral characteristics of points for selective absorption, cut-off and neutral grey 3 class; according to the coloring mechanism are divided into 3 types of coloring ion, metal colloid coloring and selenium and sulfur compounds coloring, mainly for manufacturing filter.

4, optical quartz glass. Using silica as the main ingredient, with characteristics of high temperature resistance, thermal expansion coefficient is low, high mechanical strength, chemical properties good for manufacturing of various bands through the special requirements of the prism, lens, window, mirror, etc..

5, ultraviolet and infrared optical glass. In the ultraviolet or infrared wave band with a specific optical constant and high transmittance, used as ultraviolet, infrared optical instrument or as a window material.

6, radiation resistant optical glass. Under a certain gamma ray and X ray irradiation, the visible area transmission rate is less, and the variety and grade are the same as the colorless optical glass, which is used for the manufacture of optical instruments and peep window under high energy irradiation.

Whether it is an inorganic material or organic material made of optical lenses, in the daily use, due to the friction with the dust or grit (silicon oxide) will cause the lens wear, scratches on the surface of the lens. Compared with the glass sheets, the hardness of organic materials is relatively low, and it is easier to produce scratches. Through the microscope, we can observe to scratch the surface of the lens is mainly divided into two, one is due to the gravel scratches, shallow and small, wearing glasses is not easy to detect; another is generated by the larger gravel scratches and deep and surrounding rough in regional center will affect vision.

Then through the lens coating will reduce wear and tear, you can improve the quality of the lens and extend the life of the lens.

In the process of optical lens installation, if the method is not correct, it will make the lens is contaminated. Therefore, to comply with the operating procedures.

If a large number of lenses need to be installed and removed, it is necessary to design a fixture to complete the task. The specific fixture can reduce the number of contact lenses, thereby reducing the risk of lens contamination or damage.

In addition, if the lens is not installed correctly, the laser system will not work properly, or even will be damaged. All carbon dioxide laser lenses should be installed in a certain direction. So the user should be sure that the correct direction of the lens.

Choose glasses is mainly according to the environment in the use of their work and life needs and glasses, glasses should have the performance, in the opted for glasses of the corrected visual acuity, distance, and glasses, should also consider the performance characteristics of different optical lenses are not the same as what.

Optical lens color

Vision, color and distance of the visual requirements of high and stable work, such as students, car drivers, surgeons, art workers, etc. should be selected colorless and transparent optical lenses. If the driver of the car wearing a heavy color of the lens, not sensitive to changes in distance, the distance is not accurate, easy to cause trouble.

Transmittance of lenses

Optical lens with multilayer anti reflective film, colorless optical lens and non spherical optical lens light transmittance is better.

Thickness of lens

And diopter lens size, and lens refraction rate, and frame size and shape, and pupil size and shift photocentric amount about, and astigmatism axial, and the lens properties (Bump).

Weight of lens

Glass lens is more important than the resin lens, which is related to the lens material. The same lens material, than great Bibi heavy weight, large volume than the small size (with lenses and shape and size.

Lens hardness

Glass lens than the resin lens high hardness, wear resistant.

Strength of lens

The resin lens is higher than the glass lens, and the impact is not easy to be broken.

Special function of lens

Such as anti ultraviolet, anti electromagnetic radiation, anti infrared, high temperature, oil resistance, acid and alkali, anti dispersion, anti deformation (ultra thin non spherical lens), anti glare and other functions. Such as electricity, gas lenses, lenses with computer, underwater lens, lens for fishing is different.

Lens shape

Choose the frame after the optical lens shape.

Whether it is an inorganic material or organic material made of optical lenses, in the daily use, due to the friction with the dust or grit (silicon oxide) will cause the lens wear, scratches on the surface of the lens. Compared with the glass sheets, the hardness of organic materials is relatively low, and it is easier to produce scratches. Through the microscope, we can observe to scratch the surface of the lens is mainly divided into two, one is due to the gravel scratches, shallow and small, wearing glasses is not easy to detect; another is generated by the larger gravel scratches and deep and surrounding rough in regional center will affect visual acuity test method for estimation and testing of abrasion resistant film wear resistance of the most fundamental method to be of clinical use, let glasses wearers for a period of time, then observed with a microscope and compared with lens wear. Of course, this is usually in the new technology before the formal promotion of the method used, at present we commonly used more rapid and intuitive test method is:

1) scrub trial will be optical lens are placed in filled with gravel propaganda (set of gravel size and hardness) and in certain under the control of back and forth friction. After the end of the fog, the amount of light before and after friction was measured and compared with the standard lenses.

2) test the steel wool with a specified steel wool, under certain pressure and velocity, in the number on the surface of the lens friction to and with Haze Meter before and after the friction test lens light diffuse reflection, and compare it with the standard lens.

3) the anti reflective coating on the surface of the lens is a very thin inorganic metal oxide material (thickness less than 1 microns), hard and brittle. When plated on the glass lens, the film base is relatively hard, gravel in the above across. The film is less prone to scratches; but anti reflection film is plated on the organic lens, the film base is relatively soft, gravel across the film. The film is very prone to scratches.

Can change the direction of light propagation, and can change the relative spectral distribution of ultraviolet, visible or infrared light is called optical glass. It is a kind of inorganic material, which is a kind of inorganic material by means of refraction, reflection, transmission of light through the way, or by changing the intensity or spectral distribution of light. Stable optical properties and high optical uniformity.

Optical glass is a lens, prism, mirror, window and other glass materials used in the manufacture of optical instruments or mechanical systems. Including colorless optical glass (usually referred to as optical glass), colored optical glass, radiation resistant optical glass, radiation proof glass and optical quartz glass, etc..

Optical glass has a high degree of transparency, chemical and physical properties (structure and properties), with a high degree of uniformity, with a specific and accurate optical constants. It can be divided into silicate, borate, phosphate, fluoride and sulfur compounds. According to their variety, mainly in refractive index (nD) - Abbe value (VD) to map the location classification. Traditionally nD>1.60, and nD<1.60 VD>50, all kinds of glass vd>55 constant (k) crown glass and other types of glass set for flint (f) of glass. Crown glass generally convex lens, a concave lens for flint glass. Usually crown glass belongs with the alkali borosilicate glass system, light crown glass belonging to the aluminum silicate system, crown glass and barium flint glass belongs to non alkali borosilicate glass system, the vast majority of flint glass belongs to lead the potassium silicate system. With the development of the application of optical glass, the variety of optical glass is expanding, and its composition includes almost all the elements in the periodic table.

Optical lens has a stable optical properties, the main materials are colorless optical glass, colored optical glass, infrared optical materials, crystal materials, glass materials and plastic materials, such as a variety of optical materials.

The optical homogeneity of the optical lens is not consistent with the refractive index of each point in the same piece of glass, which is caused by the uneven temperature in the annealing furnace. Light through a refractive index inhomogeneous glass, can make each part of the optical path produce irregular change, thus affecting the imaging quality of the optical system.

Due to all kinds of new varieties of optical lens in the processing or use of the performance of more or less defects, so in the expansion in the field of optical glass, in order to improve the physical and physicochemical properties of all kinds of new varieties of optical glass. As well as the production process carried out a lot of work.