Questions tagged [glasses]
The glasses tag has no usage guidance.
31 questions
0
votes
0
answers
26
views
What distances for plus and minus eyeglasses? Which are for middle distance?
My eyes can see fine close up and until about a foot or two distance from my face; after that, things begin to blur, such that the farthest distances are most blurred.
An eye doctor gave me a ...
- 101
0
votes
1
answer
40
views
Shading only one eye as a strategy to visually measure effect of sunglasses [closed]
I am trying to determine the practical effects of sunglasses in both daytime and nighttime scenarios. Specifically, that beyond a certain tint, darker lenses don't help with daytime glare (your pupils ...
2
votes
1
answer
82
views
Lensometer readout -- PSM
On the readout of single vision glasses from a Zeiss visulens 550, I have the following:
-----------------------
VISULENS 550
-----------------------
Date: yyyy/mm/dd hh:mm:ss
ID.xxxxxx
Mode: ...
- 123
1
vote
0
answers
147
views
When a person who is nearsighted doesn't wear corrective glasses, what happens?
Someone wrongly tagged as duplicate my previous question.
The question is: When a person who is nearsighted (eyeglass needs minus sign) doesn't wear corrective glasses, does it make the situation ...
- 11
3
votes
1
answer
86
views
Effect of inaccurate eyeglasses on the development of myopia
Suppose a person has myopia and requires a basic correction of −6 dioptres to restore normal distance vision. Instead, he wears weaker eyeglasses, say -5.5 or -5. Can this have an effect (positive or ...
1
vote
1
answer
3k
views
How do sphere and cylinder measurements combine in eyeglass prescriptions?
For eyeglasses, if a cylinder prescription were combined into a single spherical prescription, how would it be weighted?
As an example, suppose the prescription is S=-3.0, C=+.5×90°.
If only ...
- 631
0
votes
0
answers
98
views
Does the use of eye glasses prevent eye disease?
I'm turning 40 and went for my first eye test recently. They said I have nearsightedness. I work on a computer all day.
They gave me three quotes for eye glasses :
Option 1: (Cheapest price)
1.1 ...
- 127
-1
votes
1
answer
42
views
basil cancer on outer ear-tight glasses maybe the cause? [closed]
Can tight glasses cut the circulation to the outer ear? Thus making the outer ear fresh oxygen blood starved and it then be more susceptible to basil cancer? i have currently been diagnosed with basil ...
2
votes
1
answer
87
views
Does wearing UV blocking glasses worsen myopia in children?
I have found this article which claims (for chicken) that blocking outdoors UV light made myopia worse.
Some kids require glasses from a young age, e.g. 6 years old. Most of these glasses do have UV ...
- 181
1
vote
1
answer
186
views
Using farsighted glasses to counter nearsightedness?
Edit:
I might not have worded my question well enough. A shorter and more direct version would be:
Can nearsightedness be just a result of eyes getting accustomed to working at very close distances ...
- 111
5
votes
2
answers
116
views
Why are there different perscriptions for glasses and contacts? Help me see eye to eye on this
Why can't a prescription for glasses be used for contacts also? Isn't the eyesight still the same?
At first, I cynically thought it was just another way for my optometrist to make money -- so he had ...
- 2,124
1
vote
0
answers
19
views
Eyeglass prescription
Question edited as per advice. When prescribing eyeglasses, is there an aspect of balance between magnification and astigmatism correction? should the magnification strength be reduced when increasing ...
4
votes
1
answer
70
views
Health risk of lead crystal?
In the Wikipedia article on lead crystal it says that crystal glasses have become "rare" due to the "health risks" of lead.
This seems kind of crazy to me. Isn't the lead oxide in the glass bound ...
- 445
1
vote
0
answers
46
views
Is it normal for it to take more than 3 weeks to get used to astigmatism correcting glasses?
Is it common or realistic in the optometry industry to suggest to someone that it may take 6 weeks to adjust to new glasses?
- 111
3
votes
0
answers
68
views
Are cheap sunglasses dangerous? [closed]
Does having any plastic between your eyes and the environment automatically provide UVA and UVB protection? Or do the lenses actually have to be coated (or be comprised of a special type of plastic) ...
- 2,021
2
votes
0
answers
31
views
Do computer lens have side effects? [duplicate]
I was introduced by a spectacles shop about a new technology called computer lens which block blue light that is harmful to eyes. He says it reduces eye-strain for workers who need to be face a ...
- 683
5
votes
1
answer
5k
views
Can very tight glasses restrict blood flow to the brain?
Can extended use of glasses that are very tight-pressing against the temples inhibit blood circulation towards the brain?
I find that I get headaches if I wear tight glasses, and found a similar ...
- 153
2
votes
0
answers
85
views
Test UV protection on sunglasses
I bought sunglasses in China that claims to have UV400 protection.
I'd like to test this as my eyes' health is on the line :)
Is there any way to check the maximum UV amount these glasses can protect ...
- 121
1
vote
1
answer
91
views
Wearing under corrected diopter diving mask (hyperopia)
I have hyperoptia with roughly +5 diopters on both eyes and considering occasionally using diving mask for snorkeling in summer. The problem is, these masks usually come only up to +3.5 diopters and ...
- 111
1
vote
0
answers
65
views
Cannot read from 20 metres away - even with glasses
I have had bad eyesight from birth, and i mean bad. My lenses on my glasses are as thick as anything, without them everything is blurry unless it is a couple of inches away from my face.
Anyway, upon ...
- 11
1
vote
0
answers
38
views
Can a small monitor + powerful reading glasses be a substitute for a large monitor with same resolution?
Reading or focusing up close puts strain on the eyes and I believe can be bad in the long run. With that in mind, would keeping my monitor at a distance (3-4 feet) and using the right set of "...
- 111
1
vote
0
answers
26
views
What is my eyesight
According to my glasses prescription, both of my eyes are (or need) -1.00. I know I'm nearsighted, and it's a low number so it's not too bad. I'm trying to find what this would be as far as 20 out of ...
- 11
1
vote
0
answers
727
views
What is the physical meaning of the following two ways of measuring dioptries wrt cylinders?
I was using glasses with the following parameters:
left eye: -2.50Dsph -0.75DCyl
right eye: -2.50Dsph -0.75DCyl
Recently, the optometrist prescribed to me glasses with the following parameters:
...
- 111
1
vote
0
answers
46
views
Child with -22 power, is it equal to blindness?
Doctor have advised -22 power glasses for my 3-year old daughter. Does it equal to blindness? Will she behave like a normal child - play, fight and ask for different things (as children do), identify ...
- 11
3
votes
1
answer
8k
views
Help reading an eyeglass prescription: What does "PL" or "PC" mean?
I'm trying to purchase glasses online but I cannot figure out what the Spherical value is for the left eye (OS).
- 151
2
votes
1
answer
3k
views
Does eyesight significantly vary from day-to-day?
I think I need glasses and my visit to the optometrist has confirmed this. I've never worn glasses, and I'm new to all this, so I don't completely understand how things work.
These past few weeks, I ...
- 121
0
votes
2
answers
142
views
Increase vision clarity with eye exercices?
I haven't worn my glasses in a like a year and put them on today. I noticed that vision in one eye is slightly "off" as in, the glasses rated -2.5 power aren't correcting it fully. The difference isn'...
- 103
1
vote
0
answers
25
views
How important is having an anti-reflection layer on a glass lens?
There are many factors that play a role when a person chooses their next pair of glasses. For example, I would think that the exact material of the lens would be of crucial importance. Yet, it looks ...
- 111
8
votes
1
answer
3k
views
How is the eye score interpreted?
I recently called my Optometrist to get my eye score so that I could buy my own glasses from the chemist. I was expecting to get a "+2" or "+1" or something like that but instead they gave me ...
- 211
14
votes
3
answers
5k
views
Do computer glasses actually work? [closed]
It's very likely that I will be spending most of my life in front of a computer monitor. This is necessary for my profession and the fact that improving technology requires us to look at screens more. ...
- 313
9
votes
5
answers
39k
views
Can tight glasses cause headaches?
I've been wearing glasses since I was about 7 years old (I am now 26). I wear glasses from the moment I wake up until I go to bed (except in the shower).
I've had this problem for a very long time ...
- 191