Precision of snellen eye charts - Printable Version
+- Eyesight Improvement Forum (https://www.iblindness.org/forum)
+-- Forum: General Discussion (https://www.iblindness.org/forum/forumdisplay.php?fid=4)
+--- Forum: Bates Method (https://www.iblindness.org/forum/forumdisplay.php?fid=5)
+--- Thread: Precision of snellen eye charts (/showthread.php?tid=1242)
Precision of snellen eye charts - Alexndre - 07-15-2009
This morning, I was asking me if the snellen test cards that we can find on internet and print on a letter-format sheet are accurate.
I saw that the corresponding letter on differents charts are not always the same size.
I personally use this one:
<!-- m --><a class="postlink" href="http://www.disabled-world.com/artman/publish/eye-chart.shtml">http://www.disabled-world.com/artman/pu ... hart.shtml</a><!-- m -->
But the one on this page have smaller letters:
<!-- m --><a class="postlink" href="http://www.central-fixation.com/resources.php">http://www.central-fixation.com/resources.php</a><!-- m -->
And this one seems okay with the one I use:
<!-- m --><a class="postlink" href="http://www.i-see.org/eyecharts.html">http://www.i-see.org/eyecharts.html</a><!-- m -->
So, does someone here buyed a ''true'' snellen test card? And can you tell me what snellen is the most accurate with a true chart?
What snellen eye chart did you use?
Have a nice day!
Re: Precision of snellen eye charts - otis - 07-15-2009
Subject: What is the "perfect" size of the letters on a Snellen.
Where ever you obtain your Snellen, you should always check the following:
20/60 must be 1 inch high.
20/20 must be 3/8 inch high.
Measurements should be on a brightly illuminated Snellen.
In metric, the distanc is 6 meters.
6/6 with the letter size 0.9 cm
6/12 means the letter size must be 1.8 cm.
This will callibrate any Snellen -- for legal and personal purposes.
This should duplicate the test conditions in an "office" Snellen or the DMV test.
In general the DMV tests for 20/40 or better. It is indeed a "milestone" to verify in your Bates work that you can clear that line.
Re: Precision of snellen eye charts - Alexndre - 07-17-2009
Thank you very much for your answer!
I'll check my snellen when I will have a minute.
Have a nice day of improvement! ;D
Re: Precision of snellen eye charts - Alexndre - 07-19-2009
I verified my differents snellen charts and the one that I use have slightly smaller letter than it should be and the one on central-fixation.com have letter that are too small to be accurate. At least, it give letters of different sizes and that's what we need.
Have a nice day!
Re: Precision of snellen eye charts - clarknight - 07-19-2009
I can send you a free chart through E-Mail if you like.
Has a variety of charts in one PDF.
Not perfect sizes but you can print it to size or change on a copier.
Also just made a 8x11 Inverted E Pothooks chart.
Re: Precision of snellen eye charts - Alexndre - 07-20-2009
Thank you very much but I think I will stay with my current chart that I know by heart. It reduce my strain level to read it.
Have a nice day!
Re: Precision of snellen eye charts - josh24 - 07-29-2010
HOW IT BE POSSITIVELY POSTED WHEN THE YOU HAVE A POOR EYESIGHT!
IS IT NESCESSARY THAT YOU WIL GO TO YOUR DOCTOR AND FOLLOW
AS IT PRESCRIBED..?
how to get a girl to like you
Re: Precision of snellen eye charts - VolcomStone54 - 09-07-2010
Thanks josh24 for your given information.
Ive learned lot of ideas about this topic,
BTW im a new one in this forum.
Thanks a lot,
make money online