Assertion: eyepiece's length | /r/HasProperty | fʹ
Facets:
Source sentences:
text: The optical properties of an eyepiece are characterized by the following quantities: (1) the focal length fʹ and the angular optical magnification Гʹ, which is determined by fʹ and is the ratio of the tangent of the angle at which the virtual image is visible in the eyepiece to the tangent of the angle at which the eye would see, without the eyepiece, the intermediate image on a screen or photographic emulsion placed at the normal viewing distance (250 mm for a normal eye); (2) the field of view 2ω in the image space, that is, the angle between the extreme outside rays leaving the eyepiece; and (3) for positive eyepieces, the distance d from the last lens of the eyepiece to the exit pupil, that is, to the objective image produced by the eyepiece.
text: The optical properties of an eyepiece are characterized by the following quantities: (1) the focal length fʹ and the angular optical magnification Гʹ, which is determined by fʹ and is the ratio of the tangent of the angle at which the virtual image is visible in the eyepiece to the tangent of the angle at which the eye would see, without the eyepiece, the intermediate image on a screen or photographic emulsion placed at the normal viewing distance (250 mm for a normal eye); (2) the field of view 2ω in the image space, that is, the angle between the extreme outside rays leaving the eyepiece; and (3) for positive eyepieces, the distance d from the last lens of the eyepiece to the exit pupil, that is, to the objective image produced by the eyepiece.