Talk:Sloan letters

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Added Typography template.

It turns out that Sloan letters are available as computer fonts for both the MAC and Windows, so I am concluding that this article should have a WikiProject Typography template.--DThomsen8 (talk) 01:53, 28 October 2009 (UTC)[reply]

Second of arc????

That can't be right. Surely it should be minute of arc.

And something needs to be fixed in the wording, because it doesn't make sense that a chart invented in 1862 would use letters invented in 1959. Dpbsmith (talk) 22:27, 20 September 2010 (UTC)[reply]

I actually don't understand the language used:

“

These optotypes are used because they differ from another optotype by 1 second of arc at a constant distance and size, so that all letters will be about as likely to be recognised.

”

I'm trying this, because this is I understand the cited reference, http://www.uniroma2.it/otticafp/va.html (which also confirms that the acuity standard is one minute of arc, not one second):

These letters, unlike the ones used in older Snellen charts, are designed to give acuity testing results that are comparable to tests made using Landolt broken rings.

Dpbsmith (talk) 22:40, 20 September 2010 (UTC)[reply]

The edit is fine. However, since the term "Landolt broken ring" is rarely used, I replaced it with the more familiar "Landolt ring". Strasburger (talk) 14:41, 12 July 2022 (UTC)[reply]

Pay attention with letter D on the image!

Letter D is not the true D Sloan Letter. This is a big mistake!

You can find the original Sloan D in her original paper: SLOAN LL. New test charts for the measurement of visual acuity at far and near distances. Am J Ophthalmol. 1959 Dec;48:807-13. doi: 10.1016/0002-9394(59)90626-9. PMID: 13831682. Reference that is not cited in the Wikipedia article. Shisheta (talk) 10:14, 5 February 2024 (UTC)[reply]