Optical glass is different from ordinary glass. It is a high-quality glass that can be used to make optical lenses. It is also the main basic material for optical instruments, such as telescopes and fisheye lenses. At present, the development of optical glass has been closely integrated with the development of optical instruments, and is inseparable. With the improvement of optical technology, optical glass is constantly being put forward new requirements. What is the refractive index of optical glass?
Compared with ordinary glass, a small amount of special materials are added to optical glass during production, such as light-sensitive materials AgCl, AgBr, etc., and A small amount of sensitizer such as copper oxide and so on. Adding a small amount of these substances can make the glass extremely sensitive to light. In addition, there are two other characteristics that optical glass must possess, that is, exceptionally accurate refractive index and extremely high-precision Abbe number. In addition, there are extremely high requirements for transparency and uniformity. Here, I will give you a brief explanation on the refractive index of optical glass.
The refractive index of glass is the ratio of the speed of light propagating in vacuum to the speed of light propagating in this type of glass, which is a characteristic of glass.
As a high-quality glass, each specific optical glass has a specified standard refractive index value for a certain wavelength of light, which is essential for optical glass It is a condition for optical designers to design various optical instruments. If the refractive index of the optical glass does not meet the standard, the optical instruments manufactured by this optical glass will deviate or fail to reach the standard once used. The expected imaging effect is absolutely intolerable in the research field.
In the manufacture of optical instruments, there are strict requirements on the accuracy of the refractive index of optical glass. This requires that the refractive index error of the optical glass manufactured in the same batch is within a certain range. Of course, the greater the error Smaller is better. This is conducive to the calibration of the instrument.
In the actual use of optical glass, there is another important indicator, that is, optical uniformity, which refers to the difference of the same light at different positions in the same piece of glass. The inconsistency of refractive index is a phenomenon caused by the inconsistency of temperature in different places in the annealing furnace during the glass production process. When a beam of light passes through a piece of glass with non-uniform refractive index, the path of the light will show irregular changes, and the optical instrument will show undesirable imaging quality.