focal distance


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Related to focal distance: Effective focal length

fo·cal dis·tance

the distance from the center of a lens to its focus.

fo·cal dis·tance

(fō'kăl dis'tăns)
The distance from the center of a lens to its focus.

focal distance

In ophthalmology, the distance from the optical center of a lens to the focal point.
See also: distance

focal

1. limited to a small area or volume.
2. pertaining to or emanating from focus.

focal distance
see focal-film distance.
focal length
the distance between the lens and an object from which all rays of light are brought to a focus.
focal liver disease
widely disseminated micro-abscesses or abscesses, migration paths of helminth larvae.
focal macular melanosis
dark colored spots on the skin, not elevated above the skin surface but apt to be confused with melanosis.
focal myelitis-encephalitis
widely disseminated inflammatory lesions, usually the result of blood-borne infection, in brain and spinal cord.
focal symmetrical encephalomalacia
see focal symmetrical encephalomalacia.
focal symmetrical spinal poliomalacia
see focal symmetrical spinal poliomalacia.
focal ulcerative dermatitis
manifest by ulcers in the unfeathered anterior breast skin of 4 to 5 months old male turkeys. The incidence is influenced by litter type. Called also breast buttons.
focal zone
in ultrasound, the area of the transducer where the sound beam is most sharply focussed and where the area under examination will give the best image.
References in periodicals archive ?
The problem is that reading glasses have a finite focal distance relative to each individual, typically 16-18 inches.
The dynamic focusing lens that this systems employs is structurally similar to that of the human eye and can vary its focal distance by changing its shape.
6 to 1 zoom lens, the Polaview 110 easily is set up anywhere and has a focal distance from one meter to infinity.
With a focal distance from one meter to infinity, it can display images of more than 30 feet in size, measured diagonally.
The EverSharp multifocal recording mode utilizes the focus motor to capture multiple images from varying focal distances with the push of a button.
The Camera Focus Picker allows users to interactively set focal distances.
Baylor College of Medicine, and "Visual Function at Different Focal Distances with the Synchrony Dual Optic Accommodating IOL," presented by Ivan L.
Providing the creative and technical control found on sophisticated film cameras along with the immediacy of digital imaging, the DKC-ID1 makes it easy to capture high quality and color-accurate images in a variety of lighting conditions and focal distances.

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