A cylindrical lens is a lens which focuses light into a line instead of a point, as a spherical lens would. The curved face or faces of a cylindrical lens are sections of a cylinder, and focus the image passing through it into a line parallel to the intersection of the surface of the lens and a plane tangent to it. The lens compresses the image in the direction perpendicular to this line, and leaves it unaltered in the direction parallel to it (in the tangent plane).
A toric lens combines the effect of a cylindrical lens with that of an ordinary spherical lens.
Uses in Optometry
- Cylindrical lenses are prescribed to correct astigmatism.
- Cross cylinder, which is a combination of two cylindrical lenses with equal strength and opposite power, is used in subjective refraction for discovering astigmatism, assessing strength and axis of the astigmatic power etc.
- Maddox rod made up of parallelly arranged cylindrical lenses are used to detect Strabismus and diplopia.
- In a light sheet microscope, a cylindrical lens is placed in front of the illumination objective to create the light sheet used for imaging.
- Cylindrcal lenses are used in optical spectrometers.
- Cylindrcal lenses are used in holography.
- Doublet cylinder lens system is used in optical coherence tomography.
- Cylinder lenses are used in many laser applications also. Cylindrical lens can be used to create a laser line. Doublet cylinder lens is used to make laser sheets and circularize elliptical beams from laser diodes.
- Khurana, AK (September 2008). "Light and optics". Theory and practice of optics and refraction (2nd ed.). Elsevier. p. 24. ISBN 978-81-312-1132-8.
- "Jacksons Cross Cylinder (JCC)" (PDF). Journal of Kerala Society of Ophthalmic Surgeons.
- "Dissimilar Image Tests". www.aao.org.
- Fu, Xiao; Duan, Fajie; Jiang, Jiajia; Huang, Tingting; Ma, Ling; Lv, Changrong (1 October 2017). "Astigmatism-corrected echelle spectrometer using an off-the-shelf cylindrical lens". Applied Optics. 56 (28): 7861–7868. doi:10.1364/AO.56.007861. ISSN 2155-3165. PMID 29047771.
- Xiao, Dan; Wei, Rong; Liu, Su-Juan; Wang, Qiong-Hua (1 December 2018). "Holographic magnification system based on cylindrical lens". Optik. 174: 707–714. doi:10.1016/j.ijleo.2018.06.103. ISSN 0030-4026.
- "Fast Tomography Imaging System for Material Surface Based on Doublet-cylinder-lens in Intelligent OCT".
- "Cylinder Lens | Edmund Optics". www.edmundoptics.com.
- Jacobs, Donald H. Fundamentals of Optical Engineering. MC Graw-Hill Book Co., 1943.
- Media related to Cylindrical lenses at Wikimedia Commons