kontrastfølsomheten

Kontrastfølsomheten, also known as contrast sensitivity, refers to the ability of the visual system to detect differences in luminance or color between adjacent areas. It is a crucial component of visual acuity, determining how well an individual can discern details in their environment, especially in low light or challenging visual conditions. This sensitivity is not uniform across all spatial frequencies; the visual system is typically most sensitive to mid-range spatial frequencies and less sensitive to very high or very low frequencies.

Factors that can influence contrast sensitivity include the overall brightness of the scene (luminance), the size of the objects being viewed, and the presence of visual noise. Age is a significant factor, with contrast sensitivity generally decreasing as people get older, which can contribute to difficulties with tasks like reading or driving at night. Ocular conditions such as cataracts, glaucoma, and refractive errors can also impair contrast sensitivity by affecting how light is transmitted or focused by the eye.

Measurement of contrast sensitivity is often performed using specialized charts or devices that present patterns with varying contrasts and spatial frequencies. This testing can provide a more comprehensive assessment of visual function than standard visual acuity charts, which primarily measure the ability to see small, high-contrast details. Understanding and assessing contrast sensitivity is important for diagnosing and managing various visual impairments and for optimizing visual performance in different settings.