PubMed · 3483051
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
E A Hegenbarth. 1987. [Creative color system].. https://pubmed.ncbi.nlm.nih.gov/3483051/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
BACKGROUND: Various imaging properties of scanning laser ophthalmoscopes (SLO) such as contrast or depth discrimination, are superior to those of the traditional photographic fundus camera. However, most SLO are monochromatic whereas photographic systems produce colour images, which inherently contain information over a broad wavelength range. METHODS: An SLO system has been modified to allow simultaneous three channel imaging. Laser light sources in the visible and infrared spectrum were concurrently launched into the system. Using different wavelength triads, digital fundus images were acquired at high frame rates. RESULTS: Favourable wavelengths combinations were established and high contrast, true (red, green, blue) or false (red, green, infrared) colour images of the retina were recorded. The monochromatic frames which form the colour image exhibit improved distinctness of different retinal structures such as the nerve fibre layer, the blood vessels, and the choroid. CONCLUSIONS: A multi-channel SLO combines the advantageous imaging properties of a tunable, monochrome SLO with the benefits and convenience of colour ophthalmoscopy. The options to modify parameters such as wavelength, intensity, gain, beam profile, aperture sizes, independently for every channel assign a high degree of versatility to the system.
OBJECTIVE: An in-vitro study to examine the correlation between the distribution of the autofluorescent signal emitted from carious dentine (detected using confocal laser scanning microscopy) and its microhardness, within the depths of human dentine lesions. MATERIALS AND METHODS: Twelve carious teeth were sectioned longitudinally, the cut faces marked with a grid reference line system and colour photomicrographs taken. The same samples were imaged using confocal laser-scanning microscopy for autofluorescence and then subjected to microhardness testing using a Knoop microhardness indenter. Adjacent sound dentine was used as a control reference. Digital image superimposition allowed direct comparisons to be made between the colour, autofluorescence and microhardness of each lesion. RESULTS: Sound enamel and dentine did not autofluorescence. Autofluorescence distribution from carious dentine correlated with the highly softened tissue (detected using the Knoop indenter) and terminated at a level superficial to the translucent zone. This zone was still pigmented. Normal, sound dentine hardness levels were found deep to the translucent zone. CONCLUSIONS: A correlation existed between the zone of autofluorescence and carious dentine that was markedly softened by the carious process. These findings highlighted a possibility that the autofluorescence might be used as an in-vitro, objective histological marker for the softened, carious dentine requiring clinical excavation.
When the nervous system is presented with multiple simultaneous inputs of some variable, such as wavelength or disparity, they can be combined to give rise to qualitatively new percepts that cannot be produced by any single input value. For example, there is no single wavelength that appears white. Many models of decoding neural population codes have problems handling multiple inputs, either attempting to extract a single value of the input parameter or, in some cases, registering the presence of multiple inputs without synthesizing them into something new. These examples raise a more general issue regarding the interpretation of population codes. We propose that population decoding involves not the extraction of specific values of the physical inputs, but rather a transformation from the input space to some abstract representational space that is not simply related to physical parameters. As a specific example, a four-layer network is presented that implements a transformation from wavelength to a high-level hue-saturation color space.