What is the condition called when light rays from a distant source focus behind the retina?

The condition where light rays from a distant source focus behind the retina is known as hyperopia, commonly referred to as farsightedness. In this condition, the eye is shorter than normal or the cornea has too little curvature, leading to difficulty seeing nearby objects clearly while distant objects may appear more focused. This occurs because the light rays converge at a point beyond the retina after passing through the eye.

Understanding hyperopia is important as it can influence how individuals perceive the clarity of objects at various distances. In contrast, myopia, astigmatism, and presbyopia involve different refractive errors and changes in vision that do not specifically pertain to the focal point of distant light rays being beyond the retina. Myopia, or nearsightedness, is characterized by clear vision up close while distant vision is blurry. Astigmatism involves an irregular curvature of the cornea that causes blurred vision at all distances. Presbyopia is an age-related condition where the eye's lens loses flexibility, affecting near vision. Each of these conditions has distinct optical characteristics that differentiate them from hyperopia.