Manual of ophthalmology . Fig. 32. Fig. 33. Figure 32. This shows both meridians to be hyperopic, the hori-zontal more so than the vertical; that is compound hyperopic astig-matism^ the correction lenses being a plus sphere and a plus is a condition of axial ametropia combined with simple hyperopicastigmatism. Figure 33. This illustrates compound myopic astigmatism, the re-verse of that shown on figure 32. Both meridians focus in the vitre-ous, that is, there is an axial ametropia combined with curvatureametropia. The correcting lens is a minus sphere with a minuscylinder. REFRAC
Manual of ophthalmology . Fig. 32. Fig. 33. Figure 32. This shows both meridians to be hyperopic, the hori-zontal more so than the vertical; that is compound hyperopic astig-matism^ the correction lenses being a plus sphere and a plus is a condition of axial ametropia combined with simple hyperopicastigmatism. Figure 33. This illustrates compound myopic astigmatism, the re-verse of that shown on figure 32. Both meridians focus in the vitre-ous, that is, there is an axial ametropia combined with curvatureametropia. The correcting lens is a minus sphere with a minuscylinder. REFRACTIVE ERRORS AND THEIR DETECTION. 125 Mixed astigmatism is illustrated in figure 34. This is a conditionin which the retina of the eye occupies the positon where onemeridian focuses in front and the other back of the retina. It isa condition that requires a plus cylinder and a minus cylinder atright angles to each other. This combination lens is generally trans-posed into a sphero-cylinder. Diagnosis of refractive errors.â
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