Which of the following transpositions is the correct one?
Related question: Which of the prescriptions below has against-the-rule astigmatism?
Answer:
To transpose an astigmatic lens, first add the spherical and the cylindrical power and then alter the sign of the cylinder power and finally add 90 degrees to the existing axis. If
the axis is more than 180 degrees, takes 180 degrees from the total
degrees to get the new axis. Therefore the correct answer is D.