An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A → spherical lens with two convex faces. The radii of curvature for the two surfaces may or may not be the same.

→ bi-; → convex; → lens.

A type of → convergent lens that is concave on one surface and convex on the opposite surface. Also called → meniscus lens. Meniscus lenses are used most often in conjunction with another lens to produce an optical system of a longer or shorter → focal length than the original lens.

→ concave; → convex; → lens.

A lens that converges an incident beam of light to a focus.

→ convex; → lens.

A → convergent lens that has one flat side and one convex side. Plano-convex lenses focus parallel rays of light to a positive point, thus forming → real images.

→ plano-; → convex; → lens.