The American encyclopedia and dictionary of ophthalmology Edited by Casey AWood, assisted by a large staff of collaborators . ATION, BINOCULAR RANGE OF position of the spectacle glasses. He does find some connectionbetween such accommodation and astigmia, but the latter is notthe only factor, for some astigmic eyes do not accommodate, .whilesome anastigmatic ones do. And it is not in Bonders sense that theeye makes use now of one of the foci and then of the other, for theregion of such accommodation does not correspond to the opticaldistance between these two points. It is generally greater in
The American encyclopedia and dictionary of ophthalmology Edited by Casey AWood, assisted by a large staff of collaborators . ATION, BINOCULAR RANGE OF position of the spectacle glasses. He does find some connectionbetween such accommodation and astigmia, but the latter is notthe only factor, for some astigmic eyes do not accommodate, .whilesome anastigmatic ones do. And it is not in Bonders sense that theeye makes use now of one of the foci and then of the other, for theregion of such accommodation does not correspond to the opticaldistance between these two points. It is generally greater in eyeswith little astigmia and less in the highly astigmatic. Irregularastigmia, imperfect centration, and especially spherical aberration(q. V.) which is largely compensated by the lens in the normal con-dition, are all contributing factors. In general it results frominfluences which by diminishing visual acuity lessen the necessityof exact focussing, but the phenomenon seems independent of thesize of the circles of diffusion so far as the latter are capable ofexact measurement. {Ophthalmic Year Book, Vol. VIII, p. 59.). Changes in the Lens During lines show swelling of anterior surface during accommodation. Accommodation, Binocular range of. Bonders distinguished betweenbinocular and monocular (or absolute) range of believed that with the ordinary methods the monocular near-point is nearer to the eye than the binocular. He explained this onthe assumption that in monocular vision the lens is more stronglycurved because the ciliary muscle contracts more strongh*, owingto the stronger convergence. According to Hess, the monocular near-point is only apparentlynearer to the eye than the binocular near-point because, with theordinary methods of examination, the pupil is more decidedly con-tracted in the former case than in the determination of the binocularnear-point. If all these errors are eliminated—by instruments basedon the Scheiner exper
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectophthalmology, bookye
