Reduced eye
The reduced eye , also called the normal eye , is a schematically simplified model of the average human eye in physiological optics ( reduced schematic eye or collapsed dioptric system of the eye ). It was developed by the Swedish medic Allvar Gullstrand .
The optical system of the real human eye is adapted to the optical density of the surrounding medium air . It is made up of components with different radii and different refractive indices and consists of the cornea , lens , vitreous humor and aqueous humor in the anterior chamber between the cornea and lens.
Medium of propagation | Refractive index | radius | distance | Refractive power |
---|---|---|---|---|
Cornea | 1,376 | −7.7 mm | 0.0 mm | +43 dpt |
Eye chamber | 1,376 | +6.8 mm | 3.6 mm | −3 dpt |
lens | 1,414 | +10.0 mm | 7.2 mm | +19 dpt |
Vitreous | 1,336 | −6.0 mm | 24.4 mm |
This complex structure results in a total refractive power of about 59 D, which corresponds to a focal length of f = 1/59 D = 17 mm. For approximate calculations, the human eye of an adult can be approximated by a simple lens with a refractive power of 59 D or a focal length of 17 mm, provided that the ciliary muscle is relaxed (remote accommodation) .
literature
- Rainer Klinke , Stefan Silbernagl (Ed.): Textbook of Physiology. 4th, corrected edition. Thieme, Stuttgart et al. 2003, ISBN 3-13-796004-5 , p. 607.
- Kenneth N. Ogle: Optics. An Introduction for Ophthalmologists. Thomas, Springfield IL 1961, pp. 103, p. 163.