What are eyeglasses?
A: Eyeglasses are vision eyewear, with lenses mounted in a frame that holds them in front of a person's eyes.
Glasses are typically used for what?
A: Vision correction, such as with reading glasses and glasses used for nearsightedness.
Without the specialized lenses, they are sometimes used
A: Cosmetic purposes.
Safety glasses provide eye protection against what?
A: flying debris for construction workers or lab technicians.
Safety glasses may have protection in the lenses as
well as for what?
A: The sides of the eyes.
Some types of safety glasses are used to protect
against what type of radiation?
A: Visible and near-visible light.
Glasses are worn for eye protection in some sports,
such as what?
Glasses wearers may use what to prevent the glasses
from falling off?
A: A strap
Wearers of glasses that are used only part of the time
may have the glasses attached to a cord that goes where?
A: Around their neck, to prevent the loss of the glasses and breaking.
Sunglasses allow for better vision in what?
A: Bright daylight.
They may protect one's eyes against damage from
excessive levels of what?
A: Ultraviolet light.
Typical sunglasses lenses are tinted for protection
against bright light or polarized to do what?
A: Remove glare
Photochromic glasses are blacked out or lightly tinted
in dark or indoor conditions but turn into sunglasses when what?
A: They come in contact with ultraviolet light.
Most over-the-counter sunglasses do not have what?
A: Corrective power in the lenses
When do people with conditions that have photophobia as
a primary symptom (like certain migraine disorders or Irlen syndrome) often
A: Indoors and at night.
Specialized glasses may be used for viewing specific
visual information; what for example?
A: 3D glasses for 3D films (stereoscopy).
Corrective lenses are used to correct refractive errors
by bending the light entering the eye in order to alleviate the effects of
conditions such as what?
A: Nearsightedness (myopia), farsightedness (hypermetropia) or astigmatism.
The ability of one's eyes to accommodate their focus to
near and distant focus alters over what?
What is a common condition in people over forty years
A: Presbyopia, which is caused by the eye's crystalline lens losing elasticity, progressively reducing the ability of the lens to accommodate (i.e. to focus on objects close to the eye).
Few people have a pair of eyes that show exactly equal
A: Refractive characteristics; one eye may need a "stronger" (i.e. more refracting) lens than the other.
Corrective lenses bring the image back into focus on
A: The retina.
They are made to conform to the prescription of a what?
A: Ophthalmologist or optometrist.
People who need glasses to see often have corrective
lens restrictions on their what?
A: Their driver's licenses that require them to wear their glasses every time they drive or risk fines or jail time.