Contrast Sensitivity
Contrast Sensitivity - Related Videos
06:49
Phase Contrast and Differential Interference Contrast (DIC) Microscopy
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Cited by 26 •
2008
This protocol highlights the principles and practical applications of Phase and Differential Interference Contrast (DIC)...
01:26
Phase Contrast and Differential Interference Contrast Microscopy
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2023
Phase-Contrast Microscopes In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
05:50
Contrast Enhanced Vessel Imaging using MicroCT
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Cited by 17 •
2011
Contrast enhanced small animal vessel imaging by microCT is a rapid, cost-effective and high-throughput technique for serial in situ examination for tumor development, for analyzing the network of blood vessels that nourish them, and for following the response of tumors to preclinical therapeutic intervention(s).
10:30
Dye-sensitized Solar Cells
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2023
Source: Tamara M. Powers, Department of Chemistry, Texas A&M University Today's modern world requires the use of a large amount of energy. While we harness energy from fossil fuels such as coal and oil, these sources are nonrenewable and thus the supply is limited. To maintain our global lifestyle, we must extract energy from renewable sources. The most promising renewable source, in terms of abundance, is the sun, which provides us with more than enough solar energy to fully fuel our...
10:39
Contrast Imaging in Mouse Embryos Using High-frequency Ultrasound
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Cited by 4 •
2015
Here, we present a protocol to inject ultrasound microbubble contrast agents into living, isolated late-gestation stage murine embryos. This method enables the study of perfusion parameters and of vascular molecular markers within the embryo using contrast-enhanced high-frequency ultrasound imaging.
FAQs
Contrast sensitivity is evaluated across patterns with different spatial frequencies, allowing assessment of how the visual system processes visual detail at more than one scale. Because this processing depends on both retinal and cortical functions, performance across the pattern range can reveal functional abnormalities that a single standard acuity measurement may not show.
Visual acuity and contrast sensitivity provide different information about vision. A person may identify high-contrast detail during an acuity test yet have difficulty detecting objects that differ only slightly in luminance from their background. This distinction makes contrast sensitivity useful for identifying functional vision loss that standard acuity can miss.
Presenting targets with progressively lower contrast challenges the visual system to detect increasingly subtle luminance differences. The point at which detection becomes difficult provides information about the person's contrast performance. Repeating this assessment across relevant visual patterns helps characterize functional vision rather than relying only on recognition of sharply defined, high-contrast targets.
Testing commonly presents visual targets whose contrast is reduced step by step. The individual attempts to detect the targets while the examiner evaluates performance across the tested patterns and contrast levels. This approach produces information about sensitivity to luminance differences and can complement standard visual acuity testing when a broader assessment of visual function is needed.
In medicine, the test can help identify functional visual loss associated with cataracts, glaucoma, retinal disease, and neurological disorders. Its value is especially apparent when standard acuity does not fully reflect the person's visual difficulty. Clinicians can use the findings as part of diagnostic evaluation rather than treating acuity results as the only measure of visual function.
Results can help evaluate changes after treatment and clarify whether visual function has improved beyond what acuity alone indicates. They also support low-vision rehabilitation by identifying functional limitations that may affect everyday visual performance. Based on these findings, clinicians can inform environmental adaptations intended to make visual tasks more manageable.