Photopic vision

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Photopic vision is the vision of the eye under well-lit conditions, which provides for color perception and high spatial acuity. This type of vision is primarily mediated by cone cells in the retina of the eye.

Physiology

Photopic vision occurs at luminance levels of 10 to 10^8 cd/m². The human eye contains three types of cone cells, each sensitive to different wavelengths of light: S-cones (short-wavelength), M-cones (medium-wavelength), and L-cones (long-wavelength). These cones are responsible for the perception of color and are most effective in bright light conditions.

Comparison with Other Types of Vision

Photopic vision is one of three types of vision, the others being scotopic vision and mesopic vision. Scotopic vision occurs under low-light conditions and is mediated by rod cells, which are more sensitive to light but do not detect color. Mesopic vision is a combination of photopic and scotopic vision and occurs under intermediate lighting conditions.

Adaptation

The process of adapting from low-light to well-lit conditions is known as light adaptation. This involves the rapid adjustment of the pupil size and the chemical changes in the cone cells to become more sensitive to light. Conversely, the adaptation from bright to low-light conditions is known as dark adaptation.

Applications

Understanding photopic vision is crucial in fields such as ophthalmology, optometry, and visual ergonomics. It is also important in the design of lighting systems, display technology, and colorimetry.

See Also

• Color vision
• Visual acuity
• Retina
• Cone cells
• Rod cells
• Scotopic vision
• Mesopic vision