blurry

Blurry describes a visual or perceptual state in which edges and fine details are not sharply defined. It can occur in natural viewing, on photographs, or in other media, and may be temporary or persistent depending on the cause.

In optics, blur happens when light does not form a crisp image on the retina. This can result from defocus (an object is not at the correct focal distance), optical aberrations, or atmospheric conditions that scatter light. In photography, blur can arise from camera or subject motion, out-of-focus framing, long exposure, or atmospheric haze. Photographers often address blur by adjusting focus, increasing shutter speed, stopping down the aperture, stabilizing the camera, or using post-processing techniques.

In human vision, blurred sight commonly stems from refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), or astigmatism, as well as ocular conditions like cataracts or dry eye. Blurry vision can also be caused by fatigue, dehydration, migraines, medication side effects, or neurological issues. Some blur is temporary and related to lighting, screen brightness, or eye strain, whereas other instances may indicate a medical condition requiring evaluation.

Assessment typically involves a vision test or eye exam to determine acuity and the underlying cause. Treatments include corrective lenses (glasses or contact lenses), refractive surgery, or medical treatment for eye diseases. For display-related blur, adjusting resolution, brightness, and refresh rate or using appropriate viewing distances can help.

Overall, blur is a broad descriptor used across optics, photography, and vision to indicate reduced sharpness or clarity, with causes ranging from simple focusing issues to medical conditions.