spherical lensed eye

Simple eye that consists of a lens of one refractive index.

Тип Organ
Родительская структура simple eye

Часто задаваемые вопросы

How does a spherical lens eye achieve focus?
A spherical lensed eye contains a single lens with a uniform refractive index throughout. Light is bent (refracted) as it passes through the curved lens surfaces, converging rays onto the photoreceptor layer. Because a homogeneous sphere produces spherical aberration (peripheral rays focus at a slightly different point than central rays), many animals with this eye type compensate through the density gradient of their photoreceptors or by the positioning of the retina.
Which animals have spherical lensed eyes?
Spherical lensed eyes are common among aquatic invertebrates and fish. Many cephalopod molluscs (squid, cuttlefish), various crustaceans, and bony fish possess this type. The near-perfect spherical lens of fish eyes is particularly well-adapted for underwater vision, where the high refractive index needed (water reduces the air-glass refractive contrast) makes a sphere the most efficient geometry.
How does a spherical lens differ from a gradient-index lens?
A spherical lens with uniform refractive index suffers from spherical aberration, reducing image sharpness. Many animals (including fish and cephalopods) instead use gradient-index (GRIN) lenses, where the refractive index is highest at the center and decreases toward the periphery — this corrects for aberration and produces a sharper image. Such GRIN lenses can appear spherical externally while functioning optically superior to a uniform sphere.

Связанные структуры

mucus body coating mucous body coating mucus cocoon mucous cocoon Mullerian duct ductus paramesonephricus multi cell part structure cell part cluster multicellular anatomical structure multicellular structure multilaminar epithelium laminated epithelium multi-tissue structure multi-tissue structures multi-unit eye

Медицинский отказ от ответственности

Данный контент предназначен исключительно для образовательных и информационных целей. Он не предназначен для замены профессиональных медицинских консультаций, диагностики или лечения. Всегда обращайтесь за советом к своему врачу или другому квалифицированному медицинскому работнику по любым вопросам, связанным с состоянием вашего здоровья. Никогда не игнорируйте профессиональные медицинские советы и не откладывайте их получение из-за того, что вы прочитали на этом сайте.

Educational Disclaimer

This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for medical decisions.

Data sources: Terminologia Anatomica, Foundational Model of Anatomy, Wikidata.