Tunnel vision

Source: Wikipedia, the free encyclopedia.
Tunnel vision
Simulation of tunnel vision
SpecialtyOphthalmology

Tunnel vision is the loss of peripheral vision with retention of central vision, resulting in a constricted circular tunnel-like field of vision.[1]

Causes

Tunnel vision can be caused by:

Eyeglass users

Eyeglass users experience tunnel vision to varying degrees due to the corrective lens only providing a small area of proper focus, with the rest of the field of view beyond the lenses being unfocused and blurry. Where a naturally sighted person only needs to move their eyes to see an object far to the side or far down, the eyeglass wearer may need to move their whole head to point the eyeglasses towards the target object.[citation needed]

The eyeglass frame also blocks the view of the world with a thin opaque boundary separating the lens area from the rest of the field of view. The eyeglass frame is capable of obscuring small objects and details in the peripheral field.[citation needed]

Mask, goggle, and helmet users

Wide-field, wrap-around diving mask
Diving mask with narrow field of view
Extremely large wide-field binoculars that would not be practical to carry

Activities which require a protective mask, safety goggles, or fully enclosing protective helmet can also result in an experience approximating tunnel vision. Underwater diving masks using a single flat transparent lens usually have the lens surface several centimeters from the eyes. The lens is typically enclosed with an opaque black rubber sealing shell to keep out water. For this type of mask the peripheral field of the diver is extremely limited. Generally, the peripheral field of a diving mask is improved if the lenses are as close to the eye as possible, or if the lenses are large, multi-window, or is a curved wrap-around design.[citation needed]

Optical instruments

Binoculars, telescopes, and microscopes induce an experience of extreme tunnel vision due to the design of the optical components.

A wide field microscope or telescope generally requires much larger diameter and thicker lenses, or complex parabolic mirror assemblies, either of which results in significantly greater cost for construction of the optical device.[citation needed]

Wide-field binoculars are possible, but require bulkier, heavier, and more complex eyepieces. The diameter of the objective lenses is unimportant for field of view.[10] The widest-angle eyepieces used in telescopes are so large that two would not fit side-by-side for use in binoculars.[citation needed]

See also

  • Target fixation, a psychological phenomenon where a person at the controls of a vehicle risks inadvertently colliding with a specific object as a result of intensely focusing on it.

References

  1. ^ "Definition of Tunnel vision". MedicineNet.
  2. ^ "Glaucoma: MedlinePlus Medical Encyclopedia". www.nlm.nih.gov. Retrieved 2016-02-21.
  3. ^ "Retinitis pigmentosa". Genetics Home Reference. 2016-02-15. Retrieved 2016-02-21.
  4. ^ Effects of Alcohol on Vision Archived 2006-10-08 at the Wayback Machine
  5. ^ "Virtual Naval Hospital: United States Naval Flight Surgeon Manual: Third Edition 1991: Chapter 2: Acceleration and Vibration: Sustained Acceleration". 23 November 2005. Archived from the original on 2005-11-23.
  6. ^ Mills, Kenneth C.; Spruill, Susan E.; Kanne, Roy W.; Parkman, Katherine M.; Zhang, Ying (5 September 2016). "The Influence of Stimulants, Sedatives, and Fatigue on Tunnel Vision: Risk Factors for Driving and Piloting". Human Factors: The Journal of the Human Factors and Ergonomics Society. 43 (2): 310–327. doi:10.1518/001872001775900878. PMID 11592671. S2CID 6852335.
  7. ^ a b "Friend Statement". 5 October 2006. Archived from the original on 2006-10-05.
  8. ^ "Virtual Naval Hospital: United States Naval Flight Surgeon Manual: Third Edition 1991: Chapter 1: Oxygen Toxicity". 22 November 2005. Archived from the original on 2005-11-22.
  9. ^ "Vasovagal syncope". www.mayoclinic.org. Retrieved 2020-08-28.
  10. ^ "Meade Sports Optics - How to Select the Right Binocular". www.meade.com.

External links