Bài giảng Cơ sở khoa học vật liệu: Chương 10 - PGS. TS. Nguyễn Ngọc Hà

Understanding the optical properties of materials is fundamental to advancements across various scientific and engineering disciplines. This document provides an essential overview of how light interacts with different material types, a phenomenon crucial for developing technologies ranging from displays and sensors to optical fibers and renewable energy systems. By exploring the fundamental nature of light and its complex interplay with matter, we lay the groundwork for comprehending key optical behaviors such as reflection, absorption, and transmission. This foundational knowledge is indispensable for material scientists, engineers, and physicists seeking to design, characterize, and optimize materials for specific optical functionalities.

Students, researchers, and professionals in Material Science, Physics, Electrical Engineering, and related fields interested in the optical behavior and characteristics of various materials.

This academic text systematically introduces the optical properties of materials, commencing with a detailed exploration of the nature of light as electromagnetic radiation, characterized by both wave and particle aspects (photons). It illustrates the electromagnetic spectrum, highlighting the visible light region and the concept of color perception through the combination of monochromatic light. The core of the discussion then shifts to the interaction between light and materials. When light impinges upon a material, its intensity (I₀) is distributed among three primary phenomena: reflection (IR), absorption (IA), and transmission (IT), quantitatively expressed as I₀ = IR + IA + IT, or R + A + T = 1. The document categorizes materials based on these interactions, distinguishing between transparent materials (high transmission), opaque materials (significant absorption or scatter), and fully opaque materials (negligible transmission). Furthermore, it delves into the microscopic mechanisms underlying these interactions, explaining how light engages with the atomic nuclei, electrons, and holes within the material. This interaction is influenced by the incident wavelength and the material's intrinsic bonding structure. Concepts like Lambert's Law are introduced to provide a quantitative framework for analyzing light propagation through absorbing media. A thorough understanding of these phenomena, including emission and scatter, is vital for predicting material behavior under illumination and for innovative material design in photonics and optoelectronics.