Lènsa

Lensa

Lensa utawa uga diarani Kanta yaiku sawijining srana kang awujud kaca bening gepeng sing duwe sisi-sisi kang simetris. Lensa mono duwe kagunan kanggo ngumpulake cahya marang siji titik utawa malah nyebarake cahya kang liwat ing tengahe. Lensa sepisanan dipangerteni saka catatan sandiwara Yunani Kuno liwat cathetane Aristhophane The Clouds (424 SM) kang nyebutake anane istilah gelas-gelas pembakar (lensa cembung kang digunakake kanggo mokusake sinaring srengenge kanggo nyiptakake geni) ing karyane. Wong kang nemokake teori babagan lensa sepisanan tur uga mratelakake kadadean bayangan ana ing retina yaiku fisikawan muslim saka Arab kang asmane Alhazen (Abu Ali al-Hasan Ibn Al-Haitham)

Jinising Lènsa

Lensa kaperang dadi maneka jinis. Lensa bisa dibedakake saka bentuk sisi-sisine. Kontruksi lensa sing paling umum ditemokake yaiku lensa speris, yaiku lensa sing sudut mlengkung permukaan bidange dibandingake karo radius speris. Titikan radius sing digunakake dilambangake kanthi lambang R,sing bakal duwe nile positif nalika saben sisine mlengkung ngadohi titik pusere lensa,lan sinebut antarmuka cembung.

Kontruksi

Kontruksi lensa kang paling akeh yaiku sing awujud lensa speris, yaiku lensa sing duwe bidhang speris (mlengkung),notasi sing digunakake yaiku R.

1 - Symmetrical double convex lens.
2 - Asymmetrical double-convex lens
3 - Plano- convex lens.
4 - Positive meniscus lens.
5 - Symmetrical biconcave lens.
6 - Asymmetrical biconcave lens.
7 - Plano-concave lens.
8 - Negative meniscus lens.

Diagram penelisikan sinar kanggo lensa konvergen

Lensa cekung

Sawijining jinislensa cembung asperis.

1: Penampang lensa Fresnel
2: Penampang lensa plano konveks kanthi daya kang padha

Pranala Jaba

• Lens article at digitalartform.com
• Thin Lens Java applet
• Article on Ancient Egyptian lenses
• Lighthouse Getaway: Fresnel lens (contains photographs.)
• Pepper, Terry. "Seeing the Light: Lighthouses on the western Great Lakes".
• Random Destructive Acts via Focused Solar Radiation.
• TruckView Fresnel lens combats the HGV Blind-Spot.
• How the Fresnel lens works.
• A computer analysis of the Fresnel lens cross section depicted in the 'graphic examples' section of this very Wikipedia article.
• Applied photographic optics Book
• Book- The properties of optical glass
• Handbook of Ceramics, Glasses, and Diamonds
• Optical glass construction
• History of Optics (audio mp3) by Simon Schaffer, Professor in History and Philosophy of Science at the University of Cambridge, Jim Bennett, Director of the Museum of the History of Science at the University of Oxford and Emily Winterburn, Curator of Astronomy at the National Maritime Museum (recorded by the BBC).
• a chapter from an online textbook on refraction and lenses
• Thin Spherical Lenses on Project PHYSNET.
• Lens article at digitalartform.com
• Article on Ancient Egyptian lenses
• picture of the Ninive rock crystal lens
• Do Sensors “Outresolve” Lenses?; on lens and sensor resolution interaction.