6 doctors weighed in:
How does the mirror affect the eye chart in a visual acuity test?
6 doctors weighed in

Dr. Richard Bensinger
Ophthalmology
3 doctors agree
In brief: Lengthens light path
Most offices do not have a 20 foot lane.
But standards and available charts are made to reflect a 20 foot lane. The way to handle this is to use mirror (s) to reflect the image the proper distance to approximate a 20 foot lane. The letter images can also be enlarged or diminished as needed but this will change the standardization. A 20 foot light path is the standard.

In brief: Lengthens light path
Most offices do not have a 20 foot lane.
But standards and available charts are made to reflect a 20 foot lane. The way to handle this is to use mirror (s) to reflect the image the proper distance to approximate a 20 foot lane. The letter images can also be enlarged or diminished as needed but this will change the standardization. A 20 foot light path is the standard.
Dr. Richard Bensinger
Dr. Richard Bensinger
Thank
Dr. Joseph Barakeh
Ophthalmology
1 doctor agrees
In brief: No
The image is the same as if you were looking the entire 20 feet (or 6 meters).
The virtual image produced by the mirror is 20 feet away. Now, if the mirror is very dirty or dusty, maybe the image would be slightly affected.

In brief: No
The image is the same as if you were looking the entire 20 feet (or 6 meters).
The virtual image produced by the mirror is 20 feet away. Now, if the mirror is very dirty or dusty, maybe the image would be slightly affected.
Dr. Joseph Barakeh
Dr. Joseph Barakeh
Thank
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