Shading Effect Of The Research And Application

The method of optical detection is an important way to study the material properties. With laser coming and the rapid development of photoelectric device, the research in optics field has great significance. Because of this method of optical detection has some advantages such as non-contact, non-damage and real-time, etc. The material's refractive index, surface tension, attenuation coefficient and other parameters can be measured by studying some special optical effects such as light in the medium surface of the reflection, refraction and diffraction which may be generated when light shines on the media interface. Series of measurement methods which have broad application prospects in the measurement properties of the medium are established through using the optical effects of media and the relationship between optical effects and characteristics of the medium. Optical detection is widely used in surface measurement of solid and liquid, surface roughness, surface topography and surface defects can be measured through the use of optical detection methods. Secondly, the measurement of liquid can be divided into two categories, namely static liquid surface and dynamic liquid surface. Optical inspection method of dynamic liquid surface used to detect the law of movement of liquid surface, and then give the surface characteristics of the physical parameters. For example, physical parameters of the liquid surface can be detected by using light diffraction and light interference in the liquid surface. Optical inspection method of static liquid surface commonly use reflection effects and refraction effects which can study properties of liquid by analyzing the intensity distribution of light and the relationship between intensity distribution of light and physical parameters. The effect of light obstructing of the media surface is observed due to surface total reflection and the relationship between the liquid membrane refractive index and the radius of light obstructed is derived. According to the effect of light obstructing of the media surface, a new method for measuring liquid refractive index is founded. The method is not only of significant meaning about media's phenomenon, mechanism and regular pattern, but also does it realize wide value to real-time detection of refractive index.The main content and conclusion are as follows:1. In the paper, the progress of optical methods which are recently used to detective solid and liquid surface and the progress of optical methods are reviewed, and the merits of a variety of optical detective means are analyzed.2. Light obstructing photos of solid and liquid are observed by using a white light source. While the reported light source of laser compare with white light source, and the light obstructing photos are very clear and with no laser speckles.3. The light obstructing effect of the solid is found, and the optical pattern of the two solid materials are observed when we study the light obstructing effect of transparent solid optical materials and integrated solid optical materials. The obstructed light pattern of transparent solid optical material consists of a bright region with significantly high light intensities in the center. There is a strip-shape bright region outside of bright region. The obstructed light pattern of integrated solid optical material still consists of a bright region with significantly high light intensities in the center. There is a strip-shape dark region outside of bright region, at the same time we provide the analytic relationship between shading radius and index of refraction.4. Light obstructing effect is also observed by using a white light source, and the obtained light obstructing photos of liquid consists of a bright region with significantly high light intensities in the center and there is a strip-shape dark region outside of bright region. Moreover, the relationship between the liquid refractive index and the radius of light obstructed is derived, and according to the effect of light obstructing of liquid membrane, a new method for measuring refractive index of the liquid and concentration of the solution are founded.5. Light obstructing effect of liquid membrane is also observed by using a white light source, and the obtained light obstructing photos are very clear and with no laser speckles. The light obstructing pattern consists of a bright region with significantly high light intensities in the center, two strip-shape dark regions outside, and also a bright field between these two strip-shape dark regions. In addition, the boundaries between these bright and dark regions are clear. Moreover, the necessary and sufficient conditions of the light obstructing photos for liquid membrane are also analyzed, and the relationship between the liquid membrane refractive index and the radius of light obstructed is derived.6. In the measurement of radius of light obstructing, we can use tow methods. The first one is that we measure directly with the reading system. The rest is that we can shoot light obstructing photos with the CCD system, then asking computer to deal with the data automatically. We can use the analytic relationship between obstructing radius of liquid membrane and refractive index of liquid to install the devices for measuring. The equipment is simple, stable, and easy to operate. With this measuring method, we need less quantity of samples and monitor the liquid refraction automatically and on-line.