afocal


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afocal

(ˈeɪˌfəʊkəl)
adj
(Astronomy) astronomy denoting a method for transferring an image without bringing it into focus
Translations
References in periodicals archive ?
The objective of those standards is to specify minimum requirements for sunglasses, fashion spectacles and replacement filters that are nominally afocal (plano power)excluding prescription filtersproviding protection against solar radiation for general use including road use and driving.
It's for picking and finding a target/object, studying it, and maybe shooting an afocal snapshot if the object is bright enough.
The original telescopes were afocal, being designed to study the stars from which incident light reaching the telescope would have zero vergence.
81 J/cm2 with afocal spot size is 100um on target surface.
Try the afocal method: aim your telescope at the Moon, focusing it by eye, hold your camera (even a cell phone) so it is pointing squarely into the telescope eyepiece, and take the shot.
Actually I discovered that this type of fixed lens photography, wherein the picture is taken through some sort of optical device, is more accurately referred to as afocal photography or afocal projection and has been in use for many years.
The M98AI and A2 versions have different afocal assemblies.
Kingella kingae has been implicated in a variety of diseases, including osteoarticular infections (OAI), septic arthritis, lower respiratory tract infections, meningitis, endocarditis, and afocal bacteremia (38).
The T-piece, to fit the camera for afocal photography was, made by Mr Steve Kleyn of the Hermanus Astronomy Centre.
The direction of research changed recently towards solar imaging, and images of the Sun were taken with a 150mm aperture Hypo fitted with a 'Thousand Oaks' trimetal front-end filter 127 mm diameter, a 'Ruby' coated optics 50 mm Plossl eyepiece, which suppresses the red fringe generated by the LCA, and a Nikon 'Coolpix' camera at the afocal position.
A significant performance improvement in the Block I CLU is an increase in target identification range through use of a larger afocal lens (12X vs 9X) plus the addition of electronic zoom capability.