Image Definition

Definition, Image


the degree of distinctness in the border between two parts of a photographic image that have received different exposures. In general, the image boundary of an object having a brightness different from that of the surrounding background is always blurred. Depending on exposure conditions, the transition zone from high optical densities to low densities—the boundary region—is between 10 and 50 microns wide for modern photographic materials. A subjective impression of image definition depends on the rate at which the density in this zone changes and on the absolute difference between the densities at the zone’s edges.

Various methods of measuring definition have been proposed that use the maximum or root-mean-square gradient of the change in the optical density in the boundary region. The highest gradient—the best image definition—is achieved only at a certain optimum exposure. Unlike resolution, image definition characterizes the quality of reproduction for relatively coarse details of a photographic image. When the distance to an object is fixed, it is usually necessary to focus the lens in two different ways to obtain pictures with the best definition and resolution.


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With improvements in brightness, color depth, and image definition, Ultra HD is noticeably better than existing technology, on any size screen.
Using the latest CCD technology to give improved image definition and features including a built-in field memory for slower shutter speeds, a 'snapshot' capability and text insertion, the new OE14-370 proved popular with ROV operators immediately and its popularity continued to grow throughout 2014.
At 4x the image definition currently available, Ultra HD content requires more efficient bandwidth to deliver uninterrupted 4K, 60 frame-per-second transmissions.
The front camera is 2MP, offering better quality conference calls with the rear boasting a high image definition with an 8MP camera.
MyRay's three-layer sensors feature a thin fiber-optic plate to improve image definition and protect the silicon receptor from direct X-ray exposure.
Additional DBEF (display brilliance enhancement film) dramatically increases brightness, while a low-reflectivity, anti-glare coating ensures deeply saturated colors and crisp image definition whether indoors or lounging at an outdoor cafE[umlaut].
Ricoh's new toner technology, which has smaller, more uniform particles, produces sharp image definition and smooth transitions in gradients.
The three firms are aiming to jointly develop technology by 2011 to reduce power consumption by LCD TVs which is growing along with the increasing size of displays and higher image definition, according to the sources.
Personal videos make a candidate seem like a human being, a point the communications team can work into the narrative before the freak show moment hardens into a image definition.
The patented lens technology is said to increase contrast and image definition.
Minerals in paper and inks contribute to better image definition (dot shape) and equal or better performance with lower qualities of minerals.
For detecting small defects in thick, dense materials, IRT offers the High-Output Microfocus X-ray (HOMX) with a focal-spot size adjustable from 5 to 200 microns and geometric magnifications of defects to 100X with fine image definition.