eyepiece

(redirected from Ramsden eyepiece)
Also found in: Dictionary, Thesaurus, Encyclopedia.

eyepiece

 [i´pēs]
the lens or system of lenses of a microscope (or telescope) nearest the user's eye, serving to further magnify the image produced by the objective. Called also ocular.

eye·piece

(ī'pēs),
The compound lens at the end of the microscope tube nearest the eye; it magnifies the image made by the objective lens.

eyepiece

/eye·piece/ (-pēs) the lens or system of lenses of a microscope (or telescope) nearest the user's eye, serving to further magnify the image produced by the objective.

eyepiece

(ī′pēs′)
n.
The lens or lens group closest to the eye in an optical instrument; an ocular. Also called eyeglass.

eye·piece

(ī'pēs)
The compound lens at the end of the microscope tube nearest the eye; it magnifies the image made by the objective.

eyepiece

The lens or combination of lenses in an optical instrument (microscope, telescope, etc.) through which the observer views the image formed by the objective. The most common eyepieces are composed of two single lenses or two doublets: the lens or doublet nearer the eye is called the eye lens and the one nearer the objective is called the field lens. The role of the eyepiece is to magnify the image and to reduce the aberrations of the image formed by the objective. Syn. eye lens; eyeglass; ocular.
Huygens' eyepiece Negative eyepiece used commonly in microscopes. It consists of two planoconvex lenses mounted with their plane surfaces facing the eye. In the most common type the eye lens has a focal length half that of the field lens and the separation is equal to half the sum of the two focal lengths.
negative eyepiece Eyepiece made up of two lenses, in which the first principal focus of the eyepiece lies between the two lenses, such as in a Huygens' eyepiece.
orthoscopic eyepiece An eyepiece corrected for distortion, and which provides a wide field of view and high magnification. It consists of a triplet field lens and a single eye lens. It is used in high-power telescopes and range finders. See triplet.
positive eyepiece Eyepiece made up of two lenses in which the first principal focus of the eyepiece lies in front of the field lens, such as in a Ramsden eyepiece.
Ramsden eyepiece Positive eyepiece consisting of two planoconvex lenses mounted with their convex side facing each other and having equal focal lengths. The lenses are usually separated by two-thirds the focal length of either.

eyepiece

the lens or system of lenses of a microscope (or telescope) nearest the user's eye, serving to further magnify the image produced by the objective.