Physics Chapter 26: Vision

Can be corrected using cylindrical lenses in eyeglasses or contact lenses to compensate for the irregular shape of the eye.

Corrected using spherical lenses, which provide a uniform curvature across all axes.

Contact lenses provide better peripheral vision and correct some corneal irregularities, while glasses' position relative to the eye causes the need for constant repositioning.

Laser-assisted surgical procedure reshaping the cornea to correct vision problems.

The cornea contributes to about two-thirds of the eye's focusing power.

The ability of the lens to adjust its shape, changing its focusing power via muscle contraction/relaxation.

Lasers use a very specific, pure wavelength (e.g. 193nm UV) to precisely alter corneal tissue.

A common Laser vision correction procedure

The process of adjusting the eye's focal length to focus on objects at various distances.

Inability to see distant objects clearly, but close objects are clear; the eye over converges distant light.

Inability to see close objects clearly, but distant objects may be clear; the eye does not converge light from close objects enough.

The furthest point from the eye at which an object can be seen clearly.

Muscles that change the shape of the lens to adjust focus.

A measure of how strongly a lens converges or diverges light.

The process adapting the eye to see distant and close objects, done by changing the shape of the lens.

The range of distances at which objects can be seen clearly (25cm to infinity).

The distance from the lens to the image formed on the retina for clear vision, constant.

The closest distance at which an object can be seen clearly by the eye.

Nearsightedness; an eye defect where a person can see distant objects but not close objects.

Farsightedness; an eye defect where a person can see close objects but not distant objects.

Correcting nearsightedness with a diverging lens.

Correcting farsightedness with a converging lens.

An eye defect causing blurry vision due to uneven focusing of the eye.

The greatest distance at which a person with myopia can see clearly.

The shortest distance at which a person with hyperopia can see clearly.

How the human eye forms images and detects details and colors, along with how optical instruments enhance vision beyond the naked eye.

Cornea provides the majority of the eye's focusing power, bending light rays significantly as they enter the eye.

A measure of how much light bends when passing from one medium to another, crucial in image formation by lenses in the eye and other optical instruments.

The light-sensitive tissue at the back of the eye; crucial for converting light into signals that the brain can interpret, forming clear images.

Clear vision requires the precise focusing of an image onto the light-sensitive retina for the formation of a sharp image. The image must fall on the retina exactly to be clear.

The eye's lens dynamically modifies its shape and focusing power to create images of objects at varying distances.

Area in the retina with the highest concentration of light receptors, responsible for sharp central vision.

The adjustable opening in the eye that regulates the amount of light entering, adapting to varying light intensities without damage to the eye.

The ability of the eye-brain system to perceive the true color of an object under varying lighting conditions, even though the wavelengths entering the eye are different.

A theory proposing that the eye-brain system compares images from different parts of the retina (retinexes) to perceive the true color of objects despite varying lighting conditions.

The color an object appears under white light; it's independent of the illumination.

The process of discerning and identifying colors, primarily involving the comparison of objects under changing lighting conditions.

The color an object appears to have under specific lighting conditions. It can be different from the true color under white light.

The eye compares adjacent light receptors and enhances edges, making vision more efficient.

Organized systems within the retina that produce independent images for comparison, helping to determine the true color of an object.