What is field of vision degrees?

Field of vision (FOV), also known as visual field, refers to the maximum extent to which a person can perceive objects around them without moving their eyes or head. It is measured in degrees and is usually represented as a circular area centered on the point of fixation.

The visual field is typically described in terms of horizontal field of vision (HFOV) and vertical field of vision (VFOV), which are measured along the horizontal and vertical axes, respectively. The average horizontal field of vision for a human is approximately 200 degrees, while the average vertical field of vision is approximately 135 degrees.

Here's a breakdown of common field of vision measurements in degrees:

1. Normal FOV: A horizontal FOV of 200 degrees or wider and a vertical FOV of 135 degrees or wider are considered normal.

2. Peripheral FOV: The peripheral field of vision refers to the area outside of the central 10 degrees of vision.

3. Central FOV: The central field of vision refers to the area within the central 10 degrees of vision. It is crucial for high-acuity tasks like reading and recognizing faces.

4. Tunnel Vision: A condition in which the field of vision is significantly narrowed, resembling a tunnel, typically occurs in peripheral areas.

5. Hemianopia: This term describes the loss of half of the visual field, either on the right (right hemianopia) or the left (left hemianopia). It can be caused by damage to the optic pathways in the brain.

6. Quadrantanopia: Refers to the loss of one-quarter of the visual field, which appears as a missing wedge.

7. Scotoma: A scotoma is a blind spot or an area of reduced vision within the visual field.

8. Glaucoma: Glaucoma, a common eye condition, often leads to progressive loss of peripheral vision.

9. Macular Degeneration: Macular degeneration affects central vision and reduces visual acuity.

The standard measurement of the field of vision is performed using perimetry, a test conducted by an eye care professional. Perimetry tests are essential in detecting visual field defects, which may indicate underlying medical conditions.