摘要:

ABSTRACTThe effects of using the criterion of minimum border and brightness equality in making matches between white and monochromatic half-disks have been studied. As long as the subject fixates a point at the center of the bipartite pattern and the effects of blur and overlap or separation are reduced to a minimum the two criteria yield essentially the same results.Differences in matching can be found when bipartite fields of different size are used. These appear to be attributable to macular pigment and the distribution of photoreceptors.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

ABSTRACTIn an attempt to understand more fully the phenomenon of prism adaptation, anisometropes were examined at the reading level for the presence or absence of compensation to their induced vertical imbalance. It will be shown that the compensation is approximately equal to the prismatic imbalance, and that there also appears to be a tendency for the compensation to lag behind the amount of prism generated for higher induced prism values.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

ABSTRACTIt is possible to refract an eye by determining the power of the correcting lens along at least three preselected meridians. It is shown that measurement errors place severe restrictions on the reliability of this technique. A mathematical method of overcoming this problem is presented which involves measurement of four or more meridional powers at any convenient pre-selected orientations. The method predicts the final prescription and gives estimates of the errors in sphere power, cylinder power, and cylinder axis, while providing the refractionist with an indication of which meridional measurements should be re-evaluated if the estimated accuracy is imadequate.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

ABSTRACTAn observer with normal vision perceived brightness enhancement and desaturation when a visual target was presented intermittently. Another observer with retinitis pigmetosa (a degenerated scotopic system) saw brightness enhancement, but was unable to detect desaturation under photic intermittency.These results suggest that desaturation involves a luminosity mechanism, rather than, or as well, as a chromaticity mechanism.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

ABSTRACTContact lens flexure and the associated residual astigmatism were measured, with bord (PMMA) corneal lenses of various diameters and powers, on corneas of various toricities. Varying contact lens diameter did not alter lens flexure or residual astigmatism on any of the corneas. Varying the contact lens power did not alter lens flexure or residual astigmatism on spherical corneas. However, on toric corneas, contact lenses with higher minus power caused significantly less flexure and residual astigmatism than did contact lenses with lower minus power.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

ABSTRACTThis paper reviews the literature on psychological or behavioral factors in the development and modification of myopia. A wide variety of topics in psychology have been involved in this work, and there are a number of potentially fruitful areas for further research. In regard to the development of myopia, the following were concluded: axial length of the eyeball is a critical physiological variable; beredity plays a definite though minor role; there are personality and intellectual correlates of myopia; and excessive visual near-work behavior is almost certainly a powerful relevant factor. In regard to modification, little has as yet been accomplished, although the demonstration of temporary changes in subjective acuity and refractive error by behavioral means supports a view of myopia as a behavioral physiological disorder.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

ABSTRACTThe intraocular pressure of clinical patients seen at The Ohio State University College of Optometry Glaucoma Clinic was assessed using the American Optical Non-Contact Tonometer and the Mackay-Marg Electronic Tonometer. The intraocular pressure measured by the NCT, in general, was lower than indicated using the electronic tonometer on each eye respectively.

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1974

数据来源: OVID