pinhole


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Related to pinhole: pinhole test, Pinhole Photography

pinhole

Archery the exact centre of an archery target, in the middle of the gold zone
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

pinhole

[′pin‚hōl]
(metallurgy)
A material fault resulting from small blisters that have burst in a casting or that have formed during electroplating.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

pinhole

1. In wood, a round hole usually less than ¼ in. (0.6 cm) in diameter, caused by the boring of a beetle or worm in standing timber.
2. In a plaster coat, a surface defect resulting from trapped air bubbles.
3. In a paint film, one of many small holes caused by: (a) impurities (in the paint, on the paintbrushes or rollers, or on the surface being painted); (b) solvent bubbling; or (c) moisture.
4. In the surface of a ceramic body, glaze, or porcelain enamel, an imperfection characterized by a depression resembling a pinprick.
5. A hole in a structural member through which a pin, 2 passes and connects with another member.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
References in periodicals archive ?
where [E'.sub.1][([x.sub.1], [y.sub.1]) = [A'.sub.1] [x.sup.2.sub.1] + [y.sup.2.sub.1] [less than or equal to] R), the radius of circular aperture is also R, [r.sub.p] is the radial coordinate at the filter pinhole plane, and only intensity is considered.
You can put a screen anywhere behind the eyepieces and project a crisp, clear image onto that screen, and the image will be much larger and brighter than with a pinhole or small mirror.
Immediately after the SPECT/CT acquisition, a static pinhole image of the neck was acquired with a SKYLight gamma camera (Philips Healthcare, USA) or with Siemens Symbia or Intevo T2 systems (Siemens, Erlangen, Germany) beginning in 2015.
Our aim was for participants to minimize their use of "fast photography" and focus their energy on "slow," or the more sensory intense traditional pinhole photography, to evoke strong personal memories of their experiences.
To make a quick version of the pinhole projector, take a sheet of paper and make a very small hole in the middle of it using a pin or a thumbtack.
And then there's the worse-case scenario: that these defects are not caught--a daunting prospect considering that not all pinholes are created equal.
* The pinhole test involves directing a patient to look at a visual acuity chart, one eye at a time, through a pinhole.
Additionally pinhole style 'valves' are said to substantially limit the shelf life of the coffee.
Key to its success was the use of an ultra-light water-based composite pinhole filler (Aerowave 2501) and an aerodynamic Sikkens coatings system which reduced wind drag.
Most of the instruments recently developed for SPECT preclinical applications consider the use of pinhole collimators, given the implicit magnification factor, to overcome the limitation imposed by the detector's intrinsic spatial resolution, if the purpose is to upgrade clinical instruments (1-5).
Regardless, experts said people should not look directly at the sun during the unusual hybrid eclipse unless they use special welder's glass or view it indirectly with a pinhole filter.