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	<id>https://wiki.endmyopia.org/index.php?action=history&amp;feed=atom&amp;title=Varilux</id>
	<title>Varilux - Revision history</title>
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	<updated>2026-08-23T10:28:29Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
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		<id>https://wiki.endmyopia.org/index.php?title=Varilux&amp;diff=17183&amp;oldid=prev</id>
		<title>Imperial-beard: Create Varilux entry: history, Minkwitz optics, documented fall risk, sources</title>
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		<updated>2026-08-22T07:57:20Z</updated>

		<summary type="html">&lt;p&gt;Create Varilux entry: history, Minkwitz optics, documented fall risk, sources&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;== Varilux ==&lt;br /&gt;
&lt;br /&gt;
&amp;#039;&amp;#039;&amp;#039;Varilux&amp;#039;&amp;#039;&amp;#039; is [[Essilor]]&amp;#039;s progressive addition lens brand and the first commercially&lt;br /&gt;
successful progressive lens. It was invented by Bernard Maitenaz, patented in 1953 and launched&lt;br /&gt;
in May 1959. Over 700 million Varilux lenses have been sold since.&lt;br /&gt;
&lt;br /&gt;
=== The 1959 trial ===&lt;br /&gt;
&lt;br /&gt;
Before release, Varilux was tested on 46 people in January 1959. The recorded outcomes were&lt;br /&gt;
5 excellent, 29 good, 2 average and &amp;#039;&amp;#039;&amp;#039;10 poor&amp;#039;&amp;#039;&amp;#039;. The lens launched four months later.&lt;br /&gt;
Roughly 22% of the founding trial did badly, so non-adaptation was documented from the start&lt;br /&gt;
rather than discovered later by wearers.&lt;br /&gt;
&lt;br /&gt;
=== Why the peripheral blur cannot be removed ===&lt;br /&gt;
&lt;br /&gt;
The distortion at the sides of any progressive lens is a geometric consequence, not a&lt;br /&gt;
manufacturing defect. &amp;#039;&amp;#039;&amp;#039;Minkwitz&amp;#039;s theorem&amp;#039;&amp;#039;&amp;#039; (see Sheedy &amp;amp; Campbell, &amp;#039;&amp;#039;Optometry and Vision&lt;br /&gt;
Science&amp;#039;&amp;#039;, 2005) states that along the umbilical corridor of a progressive surface, unwanted&lt;br /&gt;
astigmatism perpendicular to the corridor increases roughly &amp;#039;&amp;#039;&amp;#039;twice as fast&amp;#039;&amp;#039;&amp;#039; as the mean&lt;br /&gt;
power increases along it.&lt;br /&gt;
&lt;br /&gt;
Two consequences follow:&lt;br /&gt;
* A stronger reading add, or a shorter corridor, produces proportionally worse peripheral blur.&lt;br /&gt;
* The distortion can be &amp;#039;&amp;#039;&amp;#039;redistributed&amp;#039;&amp;#039;&amp;#039; across the lens surface but &amp;#039;&amp;#039;&amp;#039;cannot be reduced&amp;#039;&amp;#039;&amp;#039;.&lt;br /&gt;
&lt;br /&gt;
This applies to every progressive lens from every manufacturer. Premium designs relocate the&lt;br /&gt;
distortion according to assumptions about gaze behaviour; they do not remove it.&lt;br /&gt;
&lt;br /&gt;
=== Current product lines ===&lt;br /&gt;
&lt;br /&gt;
The current flagship is the &amp;#039;&amp;#039;&amp;#039;XR series&amp;#039;&amp;#039;&amp;#039;, marketed as &amp;quot;eye-responsive&amp;quot; and using three named&lt;br /&gt;
technologies: Nanoptix, Xtend and XR-motion. &amp;#039;&amp;#039;&amp;#039;XR Comfort Max&amp;#039;&amp;#039;&amp;#039; claims an extended near zone.&lt;br /&gt;
Older &amp;#039;&amp;#039;&amp;#039;X series&amp;#039;&amp;#039;&amp;#039; and &amp;#039;&amp;#039;&amp;#039;Physio&amp;#039;&amp;#039;&amp;#039; lines remain on sale. Street prices range from about&lt;br /&gt;
$139 a pair online to $700-$900 or more for XR with coatings through a retail optician.&lt;br /&gt;
&lt;br /&gt;
=== Documented risks ===&lt;br /&gt;
&lt;br /&gt;
* Progressive lens wearers fall at roughly twice the rate of bifocal wearers: adjusted odds&lt;br /&gt;
  ratio &amp;#039;&amp;#039;&amp;#039;2.23&amp;#039;&amp;#039;&amp;#039; (Lord et al., &amp;#039;&amp;#039;Optometry and Vision Science&amp;#039;&amp;#039;, 2025, n=281). Falls per person&lt;br /&gt;
  2.31 against 1.61.&lt;br /&gt;
* Multifocal wearers fall about &amp;#039;&amp;#039;&amp;#039;2.3 times&amp;#039;&amp;#039;&amp;#039; as often as non-wearers (Lord, Dayhew &amp;amp; Howland,&lt;br /&gt;
  &amp;#039;&amp;#039;Journal of the American Geriatrics Society&amp;#039;&amp;#039;, 2002, n=156).&lt;br /&gt;
* Toe clearance becomes more variable in multifocals, though the mean is unchanged&lt;br /&gt;
  (Johnson, Buckley, Scally &amp;amp; Elliott, &amp;#039;&amp;#039;IOVS&amp;#039;&amp;#039;, 2007).&lt;br /&gt;
* A randomised controlled trial found that giving single vision distance glasses to multifocal&lt;br /&gt;
  wearers &amp;#039;&amp;#039;&amp;#039;reduced falls in those with regular outdoor activity&amp;#039;&amp;#039;&amp;#039;, while noting the switch&lt;br /&gt;
  &amp;#039;&amp;#039;&amp;#039;may be harmful for low-activity wearers&amp;#039;&amp;#039;&amp;#039; (Haran et al., &amp;#039;&amp;#039;BMJ&amp;#039;&amp;#039;, 2010, n=606).&lt;br /&gt;
* Peripheral distortion measurably corrupts optic flow, producing a false sense of upward&lt;br /&gt;
  self-motion on level ground (Sauer et al., &amp;#039;&amp;#039;iScience&amp;#039;&amp;#039;, 2021).&lt;br /&gt;
* Progressive wearers develop a distinct eye-head coordination pattern, holding the eyes near&lt;br /&gt;
  centre and turning the head instead (Rifai &amp;amp; Wahl, &amp;#039;&amp;#039;Journal of Vision&amp;#039;&amp;#039;, 2016).&lt;br /&gt;
&lt;br /&gt;
The reading segment at the bottom of the lens is focused at roughly 40 cm. Floor distance is&lt;br /&gt;
around 150 cm, so the part of the lens used to see the ground is out of focus for the ground.&lt;br /&gt;
&lt;br /&gt;
=== The endmyopia position ===&lt;br /&gt;
&lt;br /&gt;
Two pairs of [[single vision]] lenses, one for distance and a deliberately weak pair for close&lt;br /&gt;
work, remove the corridor, the peripheral distortion and the out-of-focus lower field entirely.&lt;br /&gt;
See [[Differential Glasses]] and [[Presbyopia]].&lt;br /&gt;
&lt;br /&gt;
=== External links ===&lt;br /&gt;
&lt;br /&gt;
* [https://endmyopia.org/varilux-lenses-review/ Varilux lenses review: what the research actually shows] (endmyopia.org)&lt;br /&gt;
* [https://endmyopia.org/progressive-lenses-vs-bifocal-lenses/ Bifocal lenses vs progressive lenses]&lt;br /&gt;
* [https://doi.org/10.5281/zenodo.21016339 EndMyopia Case Report Registry, DOI 10.5281/zenodo.21016339]&lt;br /&gt;
&lt;br /&gt;
[[Category:Lenses]]&lt;br /&gt;
[[Category:Presbyopia]]&lt;/div&gt;</summary>
		<author><name>Imperial-beard</name></author>
	</entry>
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