A METHOD OF CARRYING OUT A SURFACE PLASMON RESONANCE (SPR) MEASUREMENT USING A SURFACE PLASMON RESONANCE DEVICE

摘要

This invention relates to an optical phenomena that concerns with the resonant excitation iif of "Surface Charge Density" wave (also referred to as surface plasmon wave), at the I interface of highly conducting metal and insulating sample materials, using a 'total I internally reflecting p type polarized' light wave.In this invention the authors claims of a new SPR parameter that can be of fundamental importance for the study and analysis of the SPR phenomena as well as the devices that work based on the SPR effect. For convenience, it is designated as '4 K'. it is shown that the angle of incidence and the reflectance values of every point on the SPR spectrum when mapped into corresponding new state parameters ,~8, and 'L' respectively the new SPR parameter '4K' provides a simple link between them and the resulting explicit expression ~8 2 =.1/ L K R (~8) is proposed as a new formalism for the Plasmon Resonance Curve. The advantage of the proposed new parameter is that it provides a simple connection between the real and the imaginary parts of the metal dielectric function and can be estimated from the spectrum without the need for a curve fitting procedure as well as actual thickness of the metal film. Its knowledge can be of immense use in study of optical properties of ultra thin metal films as well as in the study of absorption properties of the ultra thin absorbed overlayers of samples on the metal surface. It also facilitates, inversion of device reflectance into its corresponding angular detune with utmost ease and lifts the need for expensive angle measuring gadgets or persona D1Puters in displacement measunng applications.