Function

• Pinhole glasses are made from an opaque substance such as metal or plastic and contain many small holes. These holes bring about clearer vision by only letting light rays into the eyes through the main part of the pupil.
  
  

Cataracts

• People with cataracts often see better through pinholes. A cataract doesn't allow light to enter the eye properly. Pinholes often improve the vision even with the existence of the cataracts.
  
  

Specialty Glasses

• Because of the way pinholes minimize light to the eye, they work well as sunglasses or for extremely bright conditions. They also work well in reducing the visual stress of lengthy computer work.
  
  

Advantages

• Pinhole glasses make it easier to read and do other close-up work. They easily take the place of expensive prescriptions glasses, and they are durable enough to last a lifetime.
  
  

Limitations

• Their limitations are that good lighting is required at all times, peripheral vision is severely limited, and they are not good for people who are very farsighted or who still have naturally developing vision.