Landolt ring
A Landolt C, also known as a Japanese Vision Test, Landolt ring or Landolt broken ring, is an optotype, i.e. a standardized symbol used for testing vision. It was developed by the Swiss-born ophthalmologist Edmund Landolt.
The Landolt C consists of a ring that has a gap, thus looking similar to the letter C. The gap can be at various positions (usually left, right, bottom, top and the 45° positions in between) and the task of the tested person is to decide on which side the gap is. The size of the C and its gap are reduced until the subject makes a specified rate of errors. The minimum perceivable angle of the gap is taken as measure of the visual acuity. It is generally practised in the laboratory.
The stroke width is 1/5 of the diameter, and the gap width is the same. This is identical to the letter C from a Snellen chart. The Landolt C is the standard optotype for acuity measurement in most European countries. It was standardized, together with measurement procedures, by the German DIN, as DIN 58220 (now EN ISO 8596).

This is an excerpt from the article Landolt ring from the Wikipedia free encyclopedia. A list of authors is available at Wikipedia.
The article Landolt ring at en.wikipedia.org was accessed 35 times in the last 30 days. (as of: 05/08/2014)
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Landolt C - Wikipedia, the free encyclopedia
A Landolt C, also known as a Japanese Vision Test, Landolt ring or Landolt broken ring, is an optotype, i.e. a standardized symbol used for testing vision.
en.wikipedia.org/wiki/Landolt_C
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Landolt ring - Medical Dictionary - The Free Dictionary
A test object used for measuring visual acuity consisting of an incomplete ring resembling the letter C. The width of the break and of the ring are each one-fifth of ...
medical-dictionary.thefreedictionary.com/Landolt+ring
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Landolt ring - Medical Definition and More from Merriam-Webster
one of a series of incomplete rings or circles used in some eye charts to determine visual discrimination or acuity. Biographical Note for Landolt ring. Landolt ...
www.merriam-webster.com/medical/Landolt%20ring
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[Visual acuity testing of three-year-old children using Landolt ring ...
Visual acuity testing using Landolt ring and picture targets (silhouettes of butterfly , fish, bird and tulip), was performed on 184 three-year-old subjects who had ...
www.ncbi.nlm.nih.gov/pubmed/8241539
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Near Point Landolt Ring Acuity Test - Keystone View
The "broken circle" Landolt ring test is ideal for diagnosing near-point vision acuity in children and illiterate patients. Provides Snellen equivalent values of ...
www.keystoneview.com/index.php?page=shop.product_details&flypage=&product_id=107&category_id=36&option=com_virtuemart&Itemid=105
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Far Point Landolt Ring Acuity Test - Keystone View
The "broken circle" Landolt ring test is ideal for diagnosing far-point vision acuity in children and illiterate patients. Provides Snellen equivalent values of 20/100 ...
www.keystoneview.com/index.php?page=shop.product_details&flypage=&product_id=97&category_id=36&option=com_virtuemart&Itemid=105
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Calculating Landolt C ring size based on the visual acuity | sinneb
Mar 19, 2013 ... Tiny Python script to calculate the size (5d) in meters of a Landolt C ring based on the visual acuity belonging to that ring. # determine Landolt ...
www.sinneb.net/?p=556
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Landolt rings (medical instrument) -- Encyclopedia Britannica
In the laboratory, visual acuity is measured by the Landolt C, which is a circle with a break in it. The subject is asked to state where the break is when the figure is ...
www.britannica.com/EBchecked/topic/329399/Landolt-rings
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The Development of a Precision Series of Landolt Ring Acuity Slides.
Nov 30, 1983 ... The Landolt ring was selected as the primary stimulus pattern in agreement with the International. Ophthalmological Congress of 1909.
www.dtic.mil/dtic/tr/fulltext/u2/a138974.pdf
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landmass - definition of landmass by the…
land·mass (l nd m s) n. A large unbroken area of land. landmass [ˈlændˌmæs] n (Earth Sciences / Physical Geography) a large continuous area of land, as opposed ...
www.thefreedictionary.com/landmass
Search results for "Landolt ring"
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Landolt ring in science
Visual acuity with a motion detection target compared to Landolt Rings
Sep 23, 2011... Performance Institute, College of Optometry, Pacific University, USA ... visual target compared to Landolt ring visual acuity measurements.
[PDF]Correlation of Optotypes with the Landolt Ring—
Medical Optics Laboratory, University Eye Clinic, Hamburg, Germany. WOLFGANG ... than the diameter of the Landolt ring in order to achieve the same legibility ...
Correlation of optotypes with the Landolt ring--a fresh look at the ...
Medical Optics Laboratory, University Eye Clinic, Hamburg, Germany. ... (1) letters; (2) Snellen E; and (3) KOLT test have been compared to the Landolt ring in a ...
fMRI-constrained source analysis of visual P300 in Landolt ring task
Jan 15, 2008 ... fMRI-constrained source analysis of visual P300 in Landolt ring task ... Japan; 4 Department of Orthopaedics and Traumatology, University of ...
[PDF]Motivation Results Conclusion / Outlook References ...
5. 1 Institute of Computer Science, Johannes Gutenberg University (JGU) of Mainz, Germany. We showed in this work that the Landolt ring component of the ...
[PDF]fMRI-constrained source analysis of visual P300 in Landolt ring task
Landolt ring task. LI YueZhi1†, XU Tao2, WANG LiQun3 & HU Yong4. 1 College of Mechatronics and Control Engineering, Shenzhen University, Shenzhen ...
[PDF]Correlation of Optotypes with the Landolt Ring— - Dyop.org
Medical Optics Laboratory, University Eye Clinic, Hamburg, Germany. WOLFGANG ... than the diameter of the Landolt ring in order to achieve the same legibility ...
Correlation of Optotypes with the Landolt Ring - English
Correlation of Optotypes with the Landolt ring. ... many-body fermion density matrices volume i - Cornell University. many-body fermion density matrices volume ...
[PDF]Visual Acuity - Optometry in Practice
1864), the renowned ophthalmologist from the University of Utrecht, published his ..... threshold acuity using tumbling Es or Landolt rings, especially when used  ...
Books on the term Landolt ring
Primary Care Optometry
Primary Care Optometry
Theodore Grosvenor, Theodore P. Grosvenor, 2007
The smallest pair of Konig bars that can be resolved as two bars (rather than as one) gives a measure of the subject's visual acuity. A Landolt ring (sometimes called a Landolt C), also shown in Figure 1-18, is a ring with a gap. For normal ...
Clinical Optics and Refraction: A Guide for Optometrists, ...
Clinical Optics and Refraction: A Guide for Optometrists, ...
Andrew Keirl, Caroline Christie, 2007
The Landolt ring is sometimes described as a 'four- way forced choice test' because the patient has to identify the position of the gap as up, down, left or right . If the gap is not resolved the blur circles overlap and the patient sees a ring.
Human Factors in Lighting, Second Edition
Human Factors in Lighting, Second Edition
Peter Robert Boyce, Peter R. Boyce, 2003
This book is a comprehensive review of the interaction of people and lighting and supercedes the author's classic Human Factors in Lighting.
Textbook of Ophthalmology
Textbook of Ophthalmology
Sunita Agarwal, Athiya Agarwal, David J. Apple, 2002
Similarly, 6/60 = 20/200 6/36 = 20/120 6/24 = 20/80 6/18 = 20/60 6/12 = 20/40 6/9 = 20/30 6/6 = 20/20 Landolt's Ring Test Objects Landolt's ring test objects utilizes the same principles as Snellen's charts. It is used for illiterates and the patient ...
Building for People: Behavioral Research Approaches and ...
Building for People: Behavioral Research Approaches and ...
Arthur I. Rubin, Jacqueline Elder, United States. National Bureau of Standards, 1980
R. Lythgoe (British physicist) performed a study with a Landolt ring to determine the effect of the surround on the ability to perform a simple visual acuity task: the determination of the minimum size of detail which can be resolved.
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Landolt ring
Calculating Landolt C ring size based on the visual acuity | sinneb
Landolt ring Tiny Python script to calculate the size (5d) in meters of a Landolt C ring based on the visual acuity belonging to that ring. # determine Landolt C ring size based on decimal visual acuity scales # argument: visual acuity [0.
www.sinneb.net/?p=556
PEBL Blog: Landolt Rings, Landolt Cs
A "Landolt ring" or Landolt C has been used as a visual stimulus in a number of contexts. It is especially useful as a visual of visual acuity for subjects who don't know their letters, or in situations where you can't get verbal responses.
peblblog.blogspot.com/2010/11/landolt-rings-landolt-cs.html
Deep Thoughts: XXXholic: AnotherHolic- Landolt Ring Aerosol by NisiOisin
Kimihiro Watanuki sees spirits all the time, and he doesn't want to. So, he agrees to work in the shop of Yûko Ichihara, also known as Yûko the Time-Space Witch, so that she will take his powers away.
ladyrhian.blogspot.com/2009/02/xxxholic-anotherholic-landolt-ring.html
ANOTHERHOLiC: Landolt-Ring Aerosol | honyasbookshelf
Author: Nisioisin Companion to: xxxHOLiC by CLAMP Anyone who has read CLAMP's manga xxxHOLiC will be familiar with high-school student Kimihiro Watanuki (who sees spirits) and his boss, the amazing (read childish, demanding, and unpredictable) Yuuko Ichihara. (If you haven't read the manga, please do; it's an incredible story.) In ANOTHERHOLiC, author Nisioisin tells three…
honyasbookshelf.wordpress.com/2013/01/23/anotherholic-landolt-ring-aerosol/
The Factual Enquirer: Eyes Like an Athlete
The portion of athletic prowess that may be innate and the portion that is learned through practice were investigated through a study of the eyes of college baseball players. The eye movements of eight players and eight college-aged, male non-athletes revealed the players have learned how to track a fast moving object by moving their eyes rather than having better image processing abilities in the eye itself.
factualenquirer.blogspot.com/2012/03/eyes-like-athlete.html
xxxHolic: Another Holic Landolt-Ring Aerosol
xxxHolic: Another Holic Landolt-Ring Aerosol recensione
www.nanoda.com/manga/xxxholic-another-holic-landolt-ring-aerosol/
A Landolt C | Flickr - Photo Sharing!
A Landolt C, also known as a Landolt ring or Landolt broken ring, is an optotype, i.e. a standardized symbol used for testing vision. It consists of a ring that has a gap, thus looking similar to the letter C. The gap can be at various positions (usually left, right, bottom, top and the 45° positions in between) and the task of the tested person is to decide on which side the gap is. © Raul Vasquez/ORBIS International
www.flickr.com/photos/28816130@N06/2722027263/
FAUST/xxxHolic: ANOTHERHOLIC Landolt-Ring Aerosol | Megane Blog
Veröffentlicht am 20. Juli 2012 von Keiko-sama.
megane-blog.de/?p=2003
Download Eye Test Android App
When was the last time you had your eyes tested? You can’t remember? Yeah, well, neither do I! With this eye test you can test your vision at home easily a
www.cell11.com/android/eye-test/
QUART releases quality control tool for mammography applications - MedicalPhysicsWeb
medicalphysicsweb.org/cws/article/newsfeed/48821
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