[Measuring the breath of fusion in reduced monocular and binocular visual acuity (author's transl)].

The range of fusion was measured with the synoptophore with different objects in 100 students. The visual acuity of the tested persons was reduced monocularly and binocularly by fogging occluders. The range of fusion decreases more strongly in the case of monocularly reduced vision than in the case of binocularly reduced vision to the same degree. Therefore it is not the absolute value of the reduced vision which is responsible for the decrease in the range of fusion but rather the difference between the visual acuity of both eyes. This result is important for the therapy with fogging occluders, prism foils and penalisation methods.