BAO RESEARCH

Reflective film occupies an important role in optical film. In recent years, with the rapid development of the LED and laser industries, the market has increasingly higher requirements for highly reflective films. It is generally required that high reflective films have higher reflectivity, smaller absorption, and lower scattering loss. Compared with metal films, dielectric high-reflection films undoubtedly have better optical properties.

As we all know, metal films generally have the characteristics of high reflectivity, cut-off bandwidth, good neutrality and low polarization effect. As a supplement and extension to the design and fabrication of antireflection coatings, this article describes the special applications of metals in antireflection coatings.

Starting from the electromechanical control principle of the coating machine, this chapter explains the diagnosis and treatment methods of common faults.

As we all know, moisture has a great influence on the film. This chapter first introduces the influence of substrate subsurface on film formation in a moisture-absorbing environment; then discusses the relationship between moisture absorption and film microstructure under ideal substrate surface conditions, and provides some anti-moisture solutions based on unique features of deifferent type of films.

This chapter focuses on the various initial film stacks and designs of multilayer AR coatings

In the 15th chapter, the editor elaborated on the basic concept of PID control, and used the rate control as an example to demonstrate the PID control method. This chapter focuses on explaining the influence of PID parameters on the temperature control of the coating machine and the gas pressure control of the coating process.

The PID method are adopted to control the temperature, rate and aeration of the coating machine. It has been used for nearly 70 years, and has become one of the main technologies of industrial control due to its simple struture, good stability , reliability and convenient adjustment. This chapter focus on the PID control of coating rate, which inculdes the the principle and adjustment method of PID control, and author’s opinion on abnormal phenomena of some crystal oscillators.

This chapter focuses on the principle of AR coatings, gives an example of how to look at the admittance diagram, and describes the relevant characteristics of single-layer MgF2 film. The concepts of admittance, equivalent interface, equivalent refractive index and phase will be involved.

In the last chapter, the author gave an exampleto state the influence of the coating machine structure itself on the uniformity of the film thickness distribution. In this chapter, we continue to discuss the relationship between the uniformity of the film thickness distribution and the random error from the structure of the coating machine.