patient wearing low vision readers

How a Low Vision Reader Works

Low vision readers, also known as microscopics or prism spectacles, are designed to help patients with central scotomas read. To help these patients read, everything needs to be made bigger. By magnifying everything around the scotoma, the scotoma’s effect is reduced. There are many products that magnify – CCTV’s, hand-held magnifiers, and telescopes. Each of these devices has their own particular benefits. A low vision reader is useful in that it’s portable, affordable, and can be worn on the head, freeing up both hands.

simulation of prism spectacles

What Does the Prism in Prism Spectacles Do?

When wearing glasses to make the reading material bigger, the reading material needs to be brought closer to the face in order to focus. A +10.00 needs to be about 4″ from the face to be in focus. If you try to focus on something at 4″ with both eyes, your eyes get tired very quickly.  Base-in prism reduces the eye strain associated with focusing at a close distance.

Prism Spec and Lenticular Power Availability

Chadwick Optical makes the following powers as stock items. Other powers available by request.

Base In Prism Readers Lenticulars – OD, OS, or OU  Acrylic Microscopics
  • +4w/6
  • +5w/7
  • +6w/8
  • +7w/9
  • +8w/10
  • +10w/12
  • +12w/14
  • +14w/16
  • +10.00
  • +12.00
  • +14.00
  • +16.00
  • +18.00
  • +20.00
  • +24.00
  • 6X
  • 8X
  • 10X
  • 12X

Why Chadwick Optical Prism Specs?


As an off-the-shelf product, these high-powered readers are designed to be worn by anyone. Chadwick Optical’s prismatic spectacles are designed using a high-quality spherical lens that gives edge-to edge clarity for any patient.

Chadwick Optical is a manufacturer, not a reseller. Every pair of prism specs Chadwick Optical makes is verified for power, prism and frame adjustment by our lab technicians.


Chadwick Optical stocks 15 different frames in a variety of different colors. We are the only place you can get prism readers in memory metal frames, and the only place that makes them in Trivex.


As a full-service optical lab, Chadwick Optical can customize any prism reader to include astigmatism correction and tints. We can even use a customer supplied frame.

Available Frames for Prism Readers

Economy Frames

Full View Frames (Best for Lenticular designs)

Memory Metal Frames