Results 211 to 220 of about 23,163 (262)

New Design Principles for Visual Acuity Letter Charts

Optometry and Vision Science, 1976
This paper intoduces new principles for the design and use of letter charts for the measurement of visual acuity. It is advocated that the test task should be essentially the same at each size level on the chart. Such standardization of the test task requires the use of letters of equal legibility, the same number of letters on each row, and uniform ...
I L, Bailey, J E, Lovie
openaire   +2 more sources

On the Smith Chart (Letters)

IEEE Transactions on Microwave Theory and Techniques, 1978
The Smith Chart is the complex plane of the reflection coefficient. The unique contribution of P. H. Smith was the superposed grid for identifying impedance or admittance values; however, students, when being introduced to the Chart, can often be caught up in the superposed grid.
openaire   +1 more source

Measurement of Glare Susceptibility Using Low-Contrast Letter Charts

Optometry and Vision Science, 1993
The Committee on Ophthalmic Procedures Assessment of the American Academy of Ophthalmology suggested either contrast sensitivity or low-contrast visual acuity (VA) measured before and after adding a glare source as a test for assessing overall visual disability from immature cataracts.
D, Regan, D E, Giaschi, B B, Fresco
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Performance of video‐displayed letter charts

Clinical and Experimental Optometry, 1986
A software package was developed for an Apple-II microcomputer to display Snellen letters as test charts for high speed measurement of visual acuity. With direct viewing of a 30 cm (12 inch) monitor, letter sizes can range from 6/100 to 6/6. This range can be extended by using a modified monitor to display reversed letters for indirect viewing, to ...
openaire   +1 more source

Low-Contrast Letter Charts to Detect Subtle Neuropathies

American Journal of Ophthalmology, 1988
We performed visual contrast sensitivity testing with Regan's low-contrast letter charts on 30 patients with optic neuropathies and good Snellen visual acuity. Results of this testing were compared with color vision and the presence of an afferent pupillary defect.
Mitchell D. Drucker, Peter J. Savino, Robert C. Sergott, Thomas M. Bosley, Norman J. Schatz, Paul S. Kubilis   +5 more
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Love letter to Snellen Chart

Optician
Andrew King digs into the background of the Snellen visual acuity chart, perhaps the object most associated with optometry in the minds of the public
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Low-Contrast Letter Charts as a Test of Visual Function

Ophthalmology, 1983
Visual pathway disorders can cause visual loss that is not detected by the Snellen test: visual sensitivity to coarse detail may be depressed, even when visual sensitivity to fine detail is unaffected. Sinewave grating test targets can detect such hidden visual loss. However, electronic apparatus for generating sinewave gratings is expensive, while the
D, Regan, D, Neima
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Signal processing letters: Charting a new course [Society News]

IEEE Signal Processing Magazine, 2008
SPL's primary goal is to provide rapid publication of highly original, significant contributions and timely cutting-edge ideas in all areas within the field of interest of the IEEE Signal Processing Society.
Alex Gershman, Kostas Plataniotis, K.J. Ray Liu   +2 more
openaire   +1 more source

Transmission Line Impedance Matching Using the Smith Chart (Letters)

IEEE Transactions on Microwave Theory and Techniques, 1974
A graphical computation method is described for transforming complex load impedances into resistive load impedances using transmission line matching sections. The Smith chart is used even though the characteristic impedance normalizing factor is unknown.
openaire   +1 more source

Integrative oncology: Addressing the global challenges of cancer prevention and treatment

Ca-A Cancer Journal for Clinicians, 2022
Jun J Mao,, Msce, Lorenzo Cohen, Karen M Mustian   +2 more
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