The question of whether a person can be both nearsighted and farsighted often arises from the experience of needing different visual correction for distant and close-up tasks. Nearsightedness (myopia) and farsightedness (hyperopia) are distinct refractive errors. While a single, primary refractive error cannot physically focus light both in front of and behind the retina simultaneously, other common vision conditions can layer on top of the primary error. This creates the practical effect of needing both near and far correction, a dual-vision difficulty that affects a large portion of the population as they age.
Defining Nearsightedness and Farsightedness
Nearsightedness, or myopia, occurs when light focuses in front of the retina. This misfocus happens because the eyeball is slightly too long or the cornea, the clear front surface of the eye, is too steeply curved. The retina is the light-sensitive tissue at the back of the eye where images should focus for clear vision. As a result, distant objects appear blurry, while objects held close to the eye remain clear.
Farsightedness, or hyperopia, is the opposing condition, where the light focuses behind the retina. This is usually caused by an eyeball that is shorter than average or a cornea that is flatter than normal. Individuals with hyperopia can often see distant objects with clarity, but they struggle to focus on things up close, such as reading material or a phone screen.
The Technical Answer: Simultaneous Refractive Errors
In a strict sense, an eye cannot be simultaneously myopic and hyperopic as two separate primary conditions. The image’s single focal point cannot exist in two places—both in front of and behind the retina—at once. The eye’s overall shape dictates where the bulk of light converges, which is why a person is classified as having one or the other main refractive error.
However, a technical exception exists with a condition known as mixed astigmatism. Astigmatism is a refractive error caused by an irregularly shaped cornea or lens, which resembles a football more than a spherical basketball. This irregular shape causes the light entering the eye to form two separate focal points instead of one.
In mixed astigmatism, the eye is curved so that one focal point lands in front of the retina (myopic focus), while the other lands behind the retina (hyperopic focus). This unique arrangement means that different meridians, or sections, of the same eye exhibit both nearsighted and farsighted characteristics simultaneously. This condition causes blurred vision at all distances because neither focal point lands clearly on the retina.
The Most Common Scenario: Age-Related Vision Changes
The most common reason people report feeling both nearsighted and farsighted is the onset of presbyopia, a universal age-related change in vision. Presbyopia is the gradual loss of the eye’s ability to focus on close objects, not a refractive error like myopia or hyperopia. This condition affects nearly everyone, typically beginning in the early to mid-40s.
The underlying mechanism involves the eye’s crystalline lens, which loses elasticity and becomes increasingly stiff over time. The ciliary muscles, which surround the lens, contract to change the lens’s shape for focusing on near objects. As the lens hardens, these muscles struggle to deform it sufficiently to increase its focusing power for close work.
When presbyopia develops in a person who has never needed glasses, they will simply need reading glasses for near tasks, making them functionally “farsighted” for close vision.
For someone who is already nearsighted (myopic), the situation is more complex and leads directly to the confusion. A myopic individual already wears a corrective lens to see distant objects clearly, but when presbyopia begins, their near vision starts to fail through that same distance correction.
The nearsighted person must remove their distance glasses or use a different part of a lens to see up close, because their myopia helps them focus on near objects when uncorrected. This means they require one correction for far distance and another, or none at all, for near distance. This is the source of the common perception that they are suddenly both nearsighted and farsighted.
Correcting Complex Vision Issues
Addressing the combination of a primary refractive error and presbyopia requires corrective technology that manages multiple focal points. The oldest solution is the bifocal lens, which contains two distinct areas of power separated by a visible line: the upper portion for distance vision and the lower segment for reading. Trifocals extend this concept by adding a third, intermediate-distance segment directly above the near segment to improve clarity for tasks like computer work.
A more modern and visually seamless solution is the progressive lens, often called a no-line multifocal. This lens design offers a gradual change in power from the top of the lens, which is set for distance, down through the intermediate zone, and into the strongest reading correction at the bottom. This smooth transition eliminates the noticeable image jump that occurs at the dividing lines of bifocals and trifocals.
Contact lens wearers may opt for multifocal contacts, which incorporate both distance and near prescriptions into a single lens, or monovision. Monovision is a technique where the dominant eye is corrected for distance vision, and the non-dominant eye is corrected for near vision. The brain learns to automatically select the image from the eye that provides the sharpest focus for whatever distance the person is viewing.