Fiber optic coupling sits right at the heart of modern spectroscopic instruments, letting us move light efficiently between a source, a sample, and a detector. It keeps the signal quality high while making instrument designs way more flexible and compact. Because of this, we can now do spectroscopy. One of the unique characteristics of 2D spectroscopy is the ability to characterize molecular couplings 1. The triplexer's functions focus on enhancing the coupling efficiency and selectivity, while. Coupling constants are a fundamental concept in spectroscopy, particularly in Nuclear Magnetic Resonance (NMR) spectroscopy. They play a crucial role in determining the structure of organic molecules. Correlation charts can help us.