Classification of analytical instruments that analyze molecular structure and composition of substances through light absorption, scattering, and emission characteristics. Spectroscopic analysis equipment group used for quality control, material development, and component analysis in manufacturing industries. Includes UV-visible spectrophotometers, infrared spectrophotometers, fluorescence spectrophotometers, atomic absorption spectrophotometers, Raman spectrometers, and others, supporting product quality assurance and research development through qualitative and quantitative analysis. Differs from chemical analysis equipment and physical property measurement devices in measurement principles and targets, specializing in optical methods for molecular-level analysis.