摘要:

The ability to train stereoscopic acuity has not been tested. Indirect evidence arising as a byproduct of other studies has been inconclusive. The purpose of this study was to determine if stereoscopic acuity could, in fact, be improved by training.A group of 16 subjects was measured with stereometric cards in telebinocular and divided into a control and an experimental section. The latter underwent training in an instrument in which they repeatedly adjusted one virtual object to lie in the same fronto-paralle plane as another virtual object. Post training retest showed both groups to have improved performance. The experimental section demonstrated for greater improvement, a difference statistically significant at the 0.01 level, indicating that stereoscopic acuity had been improved by training.

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

摘要:

The blinking process supplies oxygen, dissolved in the tears, to the cornea covered by a contact lens. The dimensions of the reservoir, the rate of blinking, and the efficiency of tear replacement under the lens by a blink are factors that govern the availability of oxygen to the cornea.

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

摘要:

A mathematical model for estimating the effectiveness of individual lens designs to meet the oxygen requirements of contained epithelium is developed. Predictions of the model, based on sample clinical data, are compared with measurements of oxygen uptake following stabilization of the system at selected blink frequencies.

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

摘要:

Twenty subjects made 1,000 judgments in the laboratory on the identifiability of a circle, triangle, square and rectangle of solid and open configurations at low luminance levels. The rectangle was the most identifiable with the triangle, square and circle following in order. The open configuration was almost as visible as the solid which had twice as much reflective sheeting in it. Six subjects made over 360 dynamic observations from an automobile. The various reflectorized shapes were detected at an average of 801 ± 21.4 ft while the normal white helmet was detected at 243 ± 143 feet. Recognition distance of the open triangle was the greatest, with the open circle, open square, open rectangle, total reflectorized helmet and no reflectorization following in that order.

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

摘要:

A study was carried out on volunteer off skimo families at Barrow. Alaska. The total population consisted of508 subjects with complete information including a clinical examination as well as retractions with and without eveloplegies. Correlations between refractive errors of parents and children as well as between blings are determined on 41 family units comprising 197 subjects. The correlations between parents and children were not significantly different from zero, whereas the correlations between blings were high and significant. These results were interpreted to suggest that there is no major herediary component involved in development of myopic refractions among the offspring while there is a strong environmental component operating to create the sibling correlations. These interpretations are supported by the fact that these is virtually no myopia among the grandparents or parents but approximately 58′ of the offspring are myopic.

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

摘要:

The author repeatedly measures the keratometer readings of three steel balls and the two eyes of a subject in order to establish his reliability using the keratometer. A total possible range of 0.37 D for horizontal measurements was found, and 0.75 D for vertical measurements.

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID

ISSN:0002-9408    

出版商:OVID    

年代:1969

数据来源: OVID