https://journals.aijr.org/index.php/ias <p align="justify"><a title="Click for Journal homepage" href="https://doi.org/10.21467/ias" target="_blank" rel="noopener"><img style="float: right; padding-left: 15px; padding-right: 5px;" src="/public/site/images/aabahishti/IAS_cover_page.jpg" alt="IAS"></a> International Annals of science is an open access, peer-reviewed, online multidisciplinary journal dedicated to publishing high-quality research in all areas of the Computer, Mathematics, Physical, Chemical, Biological, and Earth Sciences. Papers published by the journal represent important advances of significance within each field by AIJR Publisher.<br>International Annals of Science is registered with CrossRef with doi:10.21467/ias and ISSN of this journal is &nbsp;2456-7132 [online].</p> AIJR Publisher en-US International Annals of Science 2456-7132 <div id="copyrightNotice"> <p>Author(s) retains full copyright of their article and grants non-exclusive publishing right to International Annals of Science and its publisher "<a title="AIJR Publisher homepage" href="https://aijr.org/" target="_blank" rel="noopener">AIJR</a> (India)". Author(s) can archive pre-print, post-print, and published version/PDF to any open access, institutional repository, social media, or personal website provided that Published source must be acknowledged with citation and link to publisher version.<br />Click <a title="Copyright Policy" href="https://aijr.org/about/policies/copyright/" target="_blank" rel="noopener">here</a> for more information on Copyright policy<br />Click <a title="Licensing Policy" href="https://journals.aijr.org/index.php/ias/about#licensing">here</a> for more information on Licensing policy</p> </div> https://journals.aijr.org/index.php/ias/article/view/10176 <p>Optical technologies are integral to modern surgical practice, supporting visualization, diagnosis, guidance, and therapy across a wide range of clinical applications. The performance and limitations of optical surgical instruments are fundamentally governed by the physical principles of light generation, propagation, and interaction with biological tissue. A clear understanding of these principles is essential for correct interpretation of optical information and safe, effective use of optical technologies in surgery. This review presents the fundamental principles of optical physics underlying diagnostic and therapeutic optical instruments used in surgical practice. Emphasis is placed on wavelength-dependent light–tissue interaction, optical properties of biological tissue, illumination sources, optical components, and imaging mechanisms relevant to surgery. Established optical technologies, including surgical microscopes, endoscopes, pulse oximeters, lasers, fluorescence-based systems, and optical fibers, are discussed alongside advanced imaging and therapeutic techniques such as optical coherence tomography, confocal microscopy, spectroscopy, and photodynamic therapy. Emerging optical approaches that provide molecular and functional information are also reviewed. By integrating optical physics with clinical context, this article aims to support surgeons and clinicians in understanding and interpreting optical technologies used in modern surgical care, while highlighting recent developments and future directions in biomedical optics relevant to surgery.</p> Darakhshan Qaiser Piyush Ranjan Kamal Kataria Copyright (c) 2026 Darakhshan Qaiser, Piyush Ranjan, Anurag Srivastava http://creativecommons.org/licenses/by-nc/4.0 2026-01-15 2026-01-15 15 1 1 19 10.21467/ias.15.1.1-19