4.1.6: Prescribe & dispense spectacles for vocational use

Question 1

What is an occupational lens and what are the +ves and -ves?

Answer 1

• A reading portion
• An intermediate portion
  Advantages
• Wider field of view at near and intermediate than a varifocal
• No jump as found in an intermediate and near bifocal
  Disadvantages
• No distance portion at all – unless 1,2,3 SuperReader office view which provides very small ‘cross the office’ viewing

Question 2

How do you fit a px with occupational glasses?

Answer 2

1. Ask the patient what their working distance is
2. Look at the patient’s add
3. Work out the dioptres required for the intermediate task
   To work out the dioptres required for a certain distance
   1/dist(m) = D
   1/0.5m = 2.00D
4. Pick the lens with the most appropriate degression for that task
5. Will the resultant intermediate dioptric power have the appropriate dioptric length that the patient needs for their specified working distance at intermediate.
   To work out the dioptric distance of a lens
   1/F = m
   1/1.50D = 66cm