Focus

In infrared imaging, focus refers to the adjustment of an optical system, such as an infrared camera or microscope, to ensure a sharp and clear image. This involves aligning the lens so that light rays converge precisely on the detector, creating a clear representation of the subject. Proper focus is crucial for capturing detailed and accurate images as well as for correcting temperature information.

When an image is out of focus, the subject appears blurry or soft, indicating that the light rays do not converge properly, resulting in a lack of detail.

The depth of field, which is the range of distances within a scene that appear acceptably sharp, is influenced by factors such as the focal length of the lens, the aperture size, and the distance to the subject. A larger depth of field means more of the scene is in focus, while a smaller depth of field means only a narrow range is in focus.

There are different focusing mechanisms, including manual focus, where the user adjusts the lens focus to bring the subject into sharp focus, and motor focus, where the user adjusts the lens with a motor to achieve focus.