Dependency graph - Revision history

81.159.32.0: /* Examples */ add link to Make

2014-11-17T19:53:09Z

Examples: add link to Make

← Older revision		Revision as of 21:53, 17 November 2014
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	'''Purkinje images''' are [[Reflection (physics)\|reflection]]s of objects from the structure of the [[human eye\|eye]]. They are also known as Purkinje reflexes and as Purkinje-Sanson images. At least four Purkinje images are usually visible. The [[first Purkinje image]] (P1) is the ~~reflection from the outer surface of the~~ [~~[cornea]]~~. ~~The [[second Purkinje image]] (P2) is the reflection from the inner surface of the cornea~~. ~~The [[third Purkinje image]] (P3) is the reflection from the outer (anterior) surface of the [[lens (anatomy)\|lens]~~]. ~~The [[fourth Purkinje image]] (P4)~~ is ~~the reflection~~ from ~~the inner (posterior) surface of the lens~~. ~~Unlike the others, P4 is an inverted image.~~		Hi there, I am Alyson Boon although it is not the title on [http://koreanyelp.com/index.php?document_srl=1798&mid=SchoolNews free psychic] my birth certification. Office supervising is where my primary earnings arrives from but I've usually needed my own business. I am truly fond of handwriting but I can't make it my profession truly. For years she's been living in Kentucky but her husband wants them to move.<br><br>Look into my blog [http://conniecolin.com/xe/community/24580 good psychic] phone readings - [http://cspl.postech.ac.kr/zboard/Membersonly/144571 click the up coming website page] -

	Purkinje-Sanson images are named after [[Czech people\|Czech]] [[anatomist]] [[Jan Evangelista Purkyně]] (1787–1869) and after [[French people\|French]] [[physician]] [[Louis Joseph Sanson]] (1790–1841).

	~~The third and fourth Purkinje images can be visible from within the eye itself. Light reflected away from the surfaces~~ of ~~the lens~~ can ~~in turn reflect back into the eye from the rear surface of the cornea~~. ~~These images are, therefore, [[entoptic phenomenon\|entoptic phenomena]].~~

	~~The first and fourth Purkinje images are used by some [[eye tracker]]~~s~~, devices~~ to ~~measure the position of an eye~~.

	~~== Brightness of Purkinje Images ==~~

	~~The brightness of the Purkinje images can be determined using [[Fresnel equations\|Fresnel's equation]]:~~
	<~~math~~>~~\text{Intensity (brightness)} = (n'-n)^2/(n'+n)^2,~~<~~/math~~>
	~~where <math>n<~~/~~math> and <math>n'<~~/~~math> are the refractive indices before and after the reflecting surface~~.
	~~Purkinje image P1 is the brightest of the four then P2, P3 and P4 (P3 and P4 have about the same brightness).~~
	~~The Purkinje images can be used to assess the curvatures and separations of the surfaces in the eye.~~

	~~==See also==~~
	*[[Red-~~eye effect]]~~

	~~==External links==~~
	*[http://~~www~~.~~diku~~.dk/~~~panic~~/~~eyegaze~~/~~node9.html Explanation of using purkinje images for eye tracking.]~~

	~~{{Visual phenomena}}~~

	~~[[Category:Optics]~~]

203.106.67.96: /* Recognizing impossible evaluations */

2013-08-01T07:23:39Z

Recognizing impossible evaluations

← Older revision		Revision as of 09:23, 1 August 2013
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	~~Yoshiko~~ is ~~her title but she doesn't like when individuals use her full title~~. The ~~factor I adore most bottle tops collecting~~ and ~~now I have time to take on new issues~~. ~~Arizona has always been my living location but my spouse desires us~~ to ~~transfer. Bookkeeping has been his working day occupation for a while~~.<br><br>~~My homepage auto warranty~~ ([http://~~Beyoufirst~~.~~org~~/~~ActivityFeed~~/~~MyProfile~~/~~tabid/62/userId/31300/Default~~.~~aspx navigate here~~])		'''Purkinje images''' are [[Reflection (physics)\|reflection]]s of objects from the structure of the [[human eye\|eye]]. They are also known as Purkinje reflexes and as Purkinje-Sanson images. At least four Purkinje images are usually visible. The [[first Purkinje image]] (P1) is the reflection from the outer surface of the [[cornea]]. The [[second Purkinje image]] (P2) is the reflection from the inner surface of the cornea. The [[third Purkinje image]] (P3) is the reflection from the outer (anterior) surface of the [[lens (anatomy)\|lens]]. The [[fourth Purkinje image]] (P4) is the reflection from the inner (posterior) surface of the lens. Unlike the others, P4 is an inverted image.

			Purkinje-Sanson images are named after [[Czech people\|Czech]] [[anatomist]] [[Jan Evangelista Purkyně]] (1787–1869) and after [[French people\|French]] [[physician]] [[Louis Joseph Sanson]] (1790–1841).

			The third and fourth Purkinje images can be visible from within the eye itself. Light reflected away from the surfaces of the lens can in turn reflect back into the eye from the rear surface of the cornea. These images are, therefore, [[entoptic phenomenon\|entoptic phenomena]].

			The first and fourth Purkinje images are used by some [[eye tracker]]s, devices to measure the position of an eye.

			== Brightness of Purkinje Images ==

			The brightness of the Purkinje images can be determined using [[Fresnel equations\|Fresnel's equation]]:
			<math>\text{Intensity (brightness)} = (n'-n)^2/(n'+n)^2,</math>
			where <math>n</math> and <math>n'</math> are the refractive indices before and after the reflecting surface.
			Purkinje image P1 is the brightest of the four then P2, P3 and P4 (P3 and P4 have about the same brightness).
			The Purkinje images can be used to assess the curvatures and separations of the surfaces in the eye.

			==See also==
			*[[Red-eye effect]]

			==External links==
			*[http://www.diku.dk/~panic/eyegaze/node9.html Explanation of using purkinje images for eye tracking.]

			{{Visual phenomena}}

			[[Category:Optics]]

en>ClueBot NG: Reverting possible vandalism by 115.118.114.60 to version by Vadmium. False positive? Report it. Thanks, ClueBot NG. (1114724) (Bot)

2012-06-15T10:36:51Z

Reverting possible vandalism by 115.118.114.60 to version by Vadmium. False positive? Report it. Thanks, ClueBot NG. (1114724) (Bot)

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Yoshiko is her title but she doesn't like when individuals use her full title. The factor I adore most bottle tops collecting and now I have time to take on new issues. Arizona has always been my living location but my spouse desires us to transfer. Bookkeeping has been his working day occupation for a while.<br><br>My homepage auto warranty ([http://Beyoufirst.org/ActivityFeed/MyProfile/tabid/62/userId/31300/Default.aspx navigate here])