Section II: Lens Options for Computer Eyewear

Specialized Computer Lenses

  • Selecting the proper lens is as important for computer users as any other patient

  • The critical issue is placing the computer add in the line of sight

  • This is between the patient’s eyes and the computer display

Four Options

Patients have four options for their computer eyewear

    1. Single vision lenses

    2. Bifocal lenses

    3. Progressive addition lenses

    4. Variable Focus Near Lenses

# 1 - Single Vision

  • If computer use is constant, and patient can tolerate some distance blur, single vision can be a good choice

  • There are both advantages and limits to single vision

  • Wide field of vision is an advantage

  • There is no need to move head vertically in order to find the right power

  • Single vision is NOT a good choice for moderate to advanced presbyopes.

# 2 - Bifocals

  • Computer Rx can be incorporated in bifocals

  • Limitations:

Clear vision limited to near and distance

Broad mid range area between 2 to 6 ft. is largely ignored and remains out of focus

More on Bifocals

  • When fit in normal manner, bifocals provide no area for viewing computer screen

  • Seg will be too low and contains too much plus for proper computer viewing

  • Bifocals are a low tech solution to a high tech problem

  • One possibility: place computer power in upper segment and reading in lower

# 3 - Progressives

  • Major disadvantage is relatively narrow intermediate and near areas

  • Usually requires wearer to lift their head by 20°

  • This leads to straining neck and shoulder muscles

  • This is a common CVS symptom

Ergonomic Considerations

  • Head position - bifocals/PALs

  • Wearer must lift head 20° to see computer

  • No clear vision in and around computer area

  • Progressive wearers have limited narrow picture in and around screen

The best choice

  • The new aspheric variable focus near lens

  • This type of lens provides distortion-free near and mid-range variable vision

  • Available in CR-39 in two to three variations

To continue, click on Section Three, Lesson Two in the left column