afocal


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afocal 

Refers to a lens or an optical system with zero focal power, i.e. in which incident rays entering parallel emerge parallel. See afocal lens; aniseikonic lens.
References in periodicals archive ?
Secondly, eyes tend not to be emmetropic and, therefore, for the most part the basic afocal telescope will require modification.
Interestingly there were quite a number of afocal experiments that were conducted by both amateur and professional photographers in the late '80s and mid '90s.
My afocal gibbous Moon shown on page 39 was taken with the simplest set-up imaginable: I hand-held a Fuji super-zoom camera over the 26-mm eyepiece of my 30-year-old Celestron C90 telescope and fired away.
Among the systems covered over the course of 43 chapters are telephoto lenses, eyepieces, afocal optical systems, periscope systems, enlarging and copying lenses, projection lenses, wedge-plate and rotary-prism cameras, optically and mechanically compensated zoom lenses, copy lenses with variable magnification, gradient-index lenses, spectrographic systems, and diffractive systems.
Two measurement configurations are accommodated for testing both high numerical aperture objectives and afocal relays.
The Mono offers 1X magnification in its baseline form, rising to 3X when an optional afocal adapter is attached.
PHOTO : afocal module provides daylight observation, while the Gen 2 or Gen 3 tube is used at
Paper: "Reflective afocal broadband adaptive optics scanning ophthalmoscope" Biomedical Optics Express, Volume 2, Issue 6, pp.
It accommodates a variety of accessories, including an IR-K2 Pro Extra Long-Range IR Illuminator, 3x or 5x Mil-Spec Afocal Night Vision Lens, iPhone and night vision camera adaptors, quick-release weapon mount, and more.
This optical arrangement--telescope, eyepiece, and a camera with an attached lens--is called afocal photography.
It uses an innovative afocal design which is patented by Safilens as the company believes it is "a veritable revolution in contact lenses for presbyopia.
The Javelin CUU needs its specially designed case to protect parts like the hand grips, afocal lens, eyepiece, and battery case.