Question

A common criticism of legal definitions of blindness is that visual acuitya. is difficult to measure objectively.b. doesn't predict how well people use their remaining sight.c. is defined in different ways by different professionals.d. doesn't provide information about the cause of blindness.

Answer 1

Legal definitions of blindness, often criticized due to the reliance on visual acuity measurements like the Snellen chart, do not encompass how individuals may adapt to or utilize their sight. Nearsightedness and farsightedness are examples of vision defects where the focus on the retina is affected, but both conditions are usually correctable.

Step-by-step explanation:

A common criticism of legal definitions of blindness is that visual acuity does not predict how well people use their remaining sight. When testing vision, tools such as the Snellen chart demonstrate visual acuity by presenting letters of varying sizes; however, this test provides a rough generalization and does not account for how individuals may adapt or utilize their peripheral vision. For conditions such as nearsightedness (myopia) or farsightedness (hyperopia), the problem lies in the eye's ability to focus light directly on the retina. Myopia occurs when distant objects appear blurred because images are focused in front of the retina, while hyperopia involves difficulty focusing on close objects. These defects are commonly understood and are correctable with appropriate lenses.

Answer 2

Visual acuity assessment uses tools like the Snellen chart to determine how clearly a person can see, with vision defects like nearsightedness and farsightedness being common issues that are typically correctable with lenses.

Step-by-step explanation:

Visual acuity is a crucial aspect of determining the health and functionality of our vision system. Testing for visual acuity often involves the use of a Snellen chart, where letters decrease in size to determine the limit at which an individual can maintain sharpness of focus. An outcome such as 20/60 vision means that what someone with normal vision can see at 60 feet, the person being tested can only see at 20 feet, indicating worse than average eyesight. Furthermore, visual field testing helps in establishing the extent of peripheral vision.

Common vision defects such as nearsightedness (myopia) and farsightedness (hyperopia) can be understood using geometric optics and are often easily correctable. Myopia is where distant objects appear blurry because the image focuses in front of the retina, while hyperopia is where close objects appear blurry because the convergence of light on the retina is insufficient. Correcting these defects generally involves the use of corrective lenses that aid in focusing light rays more effectively onto the retina.