摘要:

ABSTRACT: A comparison of five independent measurements of the ocular diopiric components utilizing both ultrasonic 2nd photographic phakometric techniques was made on both eyes of twenty children under first non-cycloplegic and then one hour later, cycloplegic conditions. The variances for both the phakometric and ultrasonic measurements made under cycloplegia were not significantly different from those made in the undrugged state. Thus, the hypothesized improvement in reliability accomplisbed through the use of cycloplegia was not found experimentally. Both right and left eye ocular component values determined in the non-cycloplegic state were shown to have significantly higher validity than those for the cycloplegic state.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: Detection and resolution thresholds for blue and yellow targets against blue, green, and yellow backgrounds were measured while wearing yellow and blue filters. Yellow filters improved thresholds for yellow targets against blue backgrounds. Their effectiveness decreased (i) as the wavelength of :he background increased, (ii) as the size of the target decreased, and (iii) with the age of the observer. The blue fillers were generally ineffective. The results are for the most part explained on the basis of changes in target contrast brought about by the filters. The effectiveness of yellow facemasks for divers under certain conditions is discussed.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: A bright area on a dark ground will take on an enhanced brightness immediately next to the ground. This is known as border enhancement. Another kind of border induction occurs when the luminance of the area is intermittent: for certain frequencies the enhanced region becomes relatively large and develops a textural quality. When the two kinds of border induction are compared with respect to effects of stimulus wavelength and luminance level, it is found that they do not vary in the same manner. This indicates that although the two phenomena may be of the same origin, the relationship between them is not a simple one.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: The tilting of the front-parallel plane with a monocular reduction of retinal luminance is considered. The reduction in retinal image size with lower illumination is considered as an explanation with the inconsistencies in the evidence both in frontal plane judgments and observations of the Pulfrich effect. Experimental work shows a tilt of the frontal plane consistent with a shift in the binoculus towards the eye with the higher illumination. This movement of the binoculus is offered as a second factor affecting the frontal plane judgments with unequal retinal luminance.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: In addition to the general aspects of body imagery, the perceptual system includes (in vision) external projection pathways as an extension of the body schema. The perceptual learning which occurs with movement is concerned primarily with differentiation of the body schema, and is different from that occurring in visually guided motor activity.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: The HRR and TMC pseudo-isochromatic tests were examined for their structure by statistical analysis of test results. It is concluded that the HRR test is the best, with the restriction, however, that the official scoring method is not optional. An improved scoring, called HRR-R (from “reevaluated”) is proposed.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: The practical application of LDH reactivity methods in relation to epithelial anoxia, as described in Part I of this investigation, are demonstrated in relation to the oxygen transmissivity qualities of an experimental contact lens material.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: Optical devices used to measure thickness are based on specific radii of curvature and indices of refraction. Variations in anterior corneal radii produce negligible changes in the apparent comeal thickness, but changes in the index of refraction cause the cornea to appear thicker or thinner than it actually is.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: An objective method for determining the external projections of retinal landmarks is discussed. Using the simple optical system described, the desired measurements can be obtained accurately and rapidly.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID

摘要:

ABSTRACT: Bacterial penetration was measured using a dialysis chamber on one control lens and five lenses worn for different periods of time. This method was used to determine possible structural change in material after periods of wear.

ISSN:0002-9408    

出版商:OVID    

年代:1972

数据来源: OVID