Contrast (vision)

Contrast (vision) is a key aspect of visual perception that describes the difference in color and light between parts of an image. It is a critical factor in the ability to distinguish objects and details in a scene.

Definition[edit | edit source]

In the context of vision, contrast is defined as the difference in luminance or color that makes an object (or its representation in an image or display) distinguishable. In visual perception of the real world, contrast is determined by the difference in the color and brightness of the object and other objects within the same field of view.

Types of Contrast[edit | edit source]

There are several types of contrast, including luminance contrast, color contrast, and spatial contrast.

Luminance Contrast[edit | edit source]

Luminance contrast refers to the difference in brightness between light and dark areas. It is the most common type of contrast and is often used in black and white photography.

Color Contrast[edit | edit source]

Color contrast, also known as chromatic contrast, refers to the difference in color properties. It is used in color theory to describe how different colors can stand out from one another.

Spatial Contrast[edit | edit source]

Spatial contrast refers to the difference in luminance or color over space. It is used in the field of optometry and ophthalmology to measure the contrast sensitivity function.

Contrast Sensitivity[edit | edit source]

Contrast sensitivity is the measure of the ability to discern between luminance of different levels in a static image. Contrast sensitivity varies between individuals, is age-dependent, and can be affected by diseases such as glaucoma and macular degeneration.

Contrast in Imaging[edit | edit source]

In medical imaging, contrast is used to differentiate between different tissues. For example, in magnetic resonance imaging (MRI), contrast agents are used to increase the contrast between different tissues, making it easier to see fine details.