Photonic imaging harnesses light properties to increase airway and interstitial visibility. Autofluorescence bronchoscopy (AFB) contrasts normal mucosa from intraepithelial neoplasia by using fluorescent properties of chromophores that include extracellular elements like collagen and intracellular components like nicotinamide adenine dinucleotide (NAD). It improves sensitivity of high-grade dysplasia over white light bronchoscopy alone but suffers from a lower sensitivity. Narrow band imaging uses filtered light around blue and green spectrum which matches hemoglobin absorption; high-grade lesions can be differentiated from low grade by measuring vessel diameter. Both are approved for clinical use, but there is no well-established use for AFB or NBI outside of preinvasive lesion detection. Optical coherence tomography (OCT) captures images using near-infrared light source and can detect carcinoma, detail airway changes of asthma, and type interstitial lung disease in research studies. Confocal laser endomicroscopy uses laser light to excite the autofluorescence in elastin and can discriminate interstitial abnormalities as well as malignant patterns.