Techniques have been developed for NIR spectroscopic imaging. Inductively coupled plasma, including mass spectroscopic and atomic emission spectroscopic detection. These include spectroscopic, piezoelectric, electrochemical and fluorescent detectors. It combines the advantages of digital imaging with the attributes of spectroscopic measurements. The equilibrium between conformational isomers can be observed using a variety of spectroscopic techniques. The Rydberg formula was derived from empirical spectroscopic emission data. Another optical quality evaluation tool is spectroscopic ellipsometry. In situ ellipsometers can be of single-wavelength or spectroscopic type. Redshifts are also seen in the spectroscopic observations of astronomical objects. These signals can be obtained simultaneously, allowing direct correlation of images and spectroscopic data. MASINT chemical and spectroscopic sensors could determine its propellant. A knowledge of shape function is needed for spectroscopic curve fitting and deconvolution. Aldehydes are readily identified by spectroscopic methods. Prior to the advent of spectroscopic analysis, such methods were widely used. The exact composition may be determined by spectroscopic studies.