Optical MathPregunta 96 de 100
A patient is refracted at a 12 mm vertex with -10.00 D, but the frame sits at 16 mm. Which way does the effective power change, requiring compensation?
a.Toward more minus, so less minus is ordered
b.The lens must gain minus power
c.No change occurs
d.It becomes plus power
Explicación
Moving a minus lens farther from the eye (12 to 16 mm) increases its effective minus power, so a slightly weaker (less minus) lens is ordered to keep the correction accurate at the new vertex distance.
Practica las 100 preguntas gratis — sin registro.
Preguntas relacionadas de este tema
- Transpose -1.75 +1.25 x 060 to minus-cylinder form.
- A frame has an A measurement of 52 mm, DBL of 18 mm, and the patient's PD is 62 mm. What is the total decentration for both lenses combined?
- With a 34 mm effective diameter and 4 mm per-lens decentration, what is the approximate minimum blank size?
- What is the combined horizontal prism when the right lens gives 2 prism diopters base out and the left lens gives 1 prism diopter base out?
- Compute the spherical equivalent of +3.00 -2.00 x 090.
- How much vertical prism imbalance exists if the reading point is 8 mm below the OC in a +2.50 D right lens and a +1.00 D left lens (Prentice's rule)?
Última revisión: · proceso editorial
Equipo Editorial de PrepPass · Verificado con ABO (American Board of Opticianry) Certified Optician Exam · Cómo revisamos