Contrast detection is a method used in various fields, including photography and vision science, to identify differences in brightness and color between objects. This technique helps cameras and the human eye to focus on subjects by detecting edges and shapes based on the contrast between light and dark areas. In photography, contrast detection autofocus systems analyze the contrast in the image to determine the sharpness of the subject. When the camera lens is adjusted, the system looks for the highest contrast point, ensuring that the image is clear and well-defined. This process is essential for capturing high-quality images in different lighting conditions.