Dark Field Imaging
Dark Field Imaging - Related Videos
01:14
Dark Blood Magnetic Resonance Imaging for Visualizing Inflamed Intracranial Arteries
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2025
Start with a human patient with cerebral vasculitis, which causes inflammation and increased permeability of blood vessels in the brain.Place the patient's head inside the radiofrequency, or RF, coil of a magnetic resonance imaging, or MRI, machine.Initiate magnetic resonance angiography, or MRA, which uses RF pulses to image blood flow.Protons in flowing blood generate strong signals, making blood vessels appear bright, while weak signals from stationary tissues result in a dark...
14:25
Determining 3D Flow Fields via Multi-camera Light Field Imaging
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Cited by 7 •
2013
A technique for performing quantitative three-dimensional (3D) imaging for a range of fluid flows is presented. Using concepts from the area of Light Field Imaging, we reconstruct 3D volumes from arrays of images. Our 3D results span a broad range including velocity fields and multi-phase bubble size distributions.
04:43
Antibody Conjugated Nanoparticle-based Quantification Using Dark Field Microscopy: A Procedure to Capture and Quantify Specific Exosomes from Body Fluids
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2023
This video describes the use of low-magnification, dark-field microscopy to quantify specific exosomes in small volume biofluidic samples. The exosomes thus identified can serve as potential cancer biomarkers.
01:29
Dark Triad and Person Perception
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2025
Person perception is influenced by both external behaviors and the observer’s internal characteristics, including personality traits. Individuals with dark personality traits, comprising psychopathy, Machiavellianism, and narcissism — collectively known as the dark triad – exhibit manipulative and exploitative tendencies in social contexts. These traits affect how they perceive others and how they are perceived.The Role of Dark Personality Traits in Person PerceptionBlack et al. (2014) explored...
04:45
Light-Dark Preference Test: A Method to Study Anxiety-Related Behavior in Zebrafish
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2023
The video describes the light-dark preference assay to study the anxiety-related behavior in zebrafish following the exposure to ethanol.
FAQs
The illumination is directed at an angle so the unrefracted beam does not enter the objective. Structures within the specimen scatter part of that light, redirecting it into the lens. The resulting signal makes scattering features appear bright against a dark field, allowing transparent biological material to become visible without relying on absorbed dyes.
Transparency does not prevent a specimen from redirecting light. Differences in shape, surface features, and other structures can scatter the oblique illumination toward the objective, producing localized brightness. Consequently, image intensity reflects how strongly features scatter light rather than simply showing their internal contents, which affects how biological structures should be interpreted.
Dark Field Imaging creates contrast through scattered light rather than through a dye that changes how the specimen absorbs or transmits illumination. This distinction is important for examining living samples whose appearance or condition could be altered by staining. However, scattering-based contrast generally reveals external appearance more effectively than internal structural detail.
A researcher places the specimen in the microscope’s oblique illumination path and uses an objective positioned so the direct beam is excluded. Light redirected by cells, microorganisms, or particles then enters the objective and forms the visible image. The method therefore depends on the specimen producing enough scattered light to distinguish its features from the dark background.
The approach is useful for transparent, unstained material that would be difficult to see through ordinary transmitted brightness alone. Examples supported by the method include microorganisms, thin cells, and particles suspended in liquid. These specimens can provide visible differences in shape, motion, or surface appearance without requiring a staining step.
Images can reveal specimen shape, movement, and surface features, making the technique valuable for observing microorganisms and other thin or suspended material. Interpretation remains limited because brightness comes from scattering, not a complete map of internal anatomy. As a result, the method is better suited to external or overall visual behavior than detailed internal structure.