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 ?
This decision derives from reasoning that overlooks the effects of HUD focal distance on perceptual judgment and, furthermore, is supported by scanty evidence.
These enable the laser to maintain proper focal distance as workpiece height changes.
Camera digital single lens reflex, slr single lens, accompanied by flash, professional, objective wide angle lens, telephoto zoom lentre focal distance, and telephoto zoom lens 18-300 .
The working head featured ZnSe focalisation convex lens, with 200 mm focal distance, and 0.
For our experiment we have used a normal optical objective with a focal distance of 12 mm and a recording rate of 250 frames/second with a maximum resolution of 640 x 480 pixels.
The tubes' lens mount has been redesigned to accommodate EF lenses as well as the new EF-S lens that utilizes Short Back Focal Distance Optics.
The focal distance changes depending on the type of lens (5" and 7.
Patran to simulate the contraction and relaxation of the muscles and fibers in the eye, which are responsible for changing focal distance.
With the Expression 1680's unique Dual-Focus Mechanism, the focal distance can be changed to 2.
With the Expression 1600's unique Dual-Focus Mechanism, the focal distance can be changed to 2.
The focal distance of the projection system is reduced by optimizing the configuration of the 11 aspherical plastic and glass lenses.
Designed for different measurement tasks, each family has specific optical angles, spot geometries and focal distances.

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