Optical coherence tomography (OCT) is an optical signal acquisition and processing method. OCT can deliver high resolution images because it is based on light, rather than sound or radio frequency. An optical beam is directed at the tissue, and a small portion of this light that reflects from sub-surface features is collected. By doing so, the OCT can build up clear 3D images of thick samples by rejecting background signal while collecting light directly reflected from surfaces of interest. These images enable optometrists to detect early signs of eye conditions such as retinal and optic nerve diseases, glaucoma, macular degeneration and diabetic retinopathy even before symptoms appear. If a problem is detected, OCT results can be sent to specialists, ensuring enhanced follow-up care.