From Non-linear Optics to Next-generation Imaging: A Journey through Non-linear Imaging Techniques

Abstract

Nonlinear optics (NLO) offers transformative capabilities in the realm of imaging, particularly within the field of microscopy. This review provides an exhaustive insight into the principles, techniques, and advancements of nonlinear optical imaging. Initially, we define the core concept of nonlinearity and its crucial role in optics. The survey then delves into some of the most prominent NLO imaging techniques in microscopy that have heralded new dimensions in imaging capabilities, especially in surmounting the diffraction limit. The relationship between contrast enhancement and signal-to-noise ratio (SNR) is detailed, with a spotlight on the profound implications of improved SNR on image clarity. Our review underscores the pivotal applications of NLO in biological and medical imaging, elucidating its transformative impact across various disciplines. The inevitable technical constraints and limitations of nonlinear imaging are also addressed, complemented by a discussion on potential strategies to overcome such barriers. The future trajectory of nonlinear imaging is anticipated to be profound, with advancements paving the way for groundbreaking developments. A special section is dedicated to revealing the symbiotic relationship between artificial intelligence and NLO in amplifying the scientific and medical possibilities. In summation, this review offers a panoramic view of its current status and future prospects.