Illuminant-adaptive diffractive-optical RGB color sensor: 3D grating-optical cross-correlator calculating colored shadows in human vision

2003 ◽  
Author(s):  
Norbert Lauinger
Keyword(s):  
2020 ◽  
Vol 66 (6) ◽  
pp. 601-606 ◽  
Author(s):  
Alex D Potash ◽  
Daniel U Greene ◽  
Gabrielle A Foursa ◽  
Verity L Mathis ◽  
L Mike Conner ◽  
...  

Abstract An animal’s pelage, feather, or skin color can serve a variety of functions, so it is important to have multiple standardized methods for measuring color. One of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of animals. New technology in the form of a commercially available handheld digital color sensor could provide an alternative to photography-based animal color measurements. To determine whether a digital color sensor could be used to measure animal coloration, we tested the ability of a digital color sensor to measure coloration of mammalian, avian, and lepidopteran museums specimens. We compared results from the sensor to measurements taken using traditional photography methods. Our study yielded significant differences between photography-based and digital color sensor measurements of brightness (light to dark) and colors along the green to red spectrum. There was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow spectrum. The average difference in recorded color (ΔE) by the 2 methods was above the threshold at which humans can perceive a difference. There were significant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring tool. However, the sensor’s small aperture and narrow light spectrum range designed for human-vision limit its value for ecological research. We discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field.


1976 ◽  
Vol 31 (2) ◽  
pp. 125-134 ◽  
Author(s):  
Lorrin A. Riggs
Keyword(s):  

1985 ◽  
Vol 30 (1) ◽  
pp. 47-47
Author(s):  
Herman Bouma
Keyword(s):  

Author(s):  
Joseph F. Boudreau ◽  
Eric S. Swanson

This chapter deals with two related problems occurring frequently in the physical sciences: first, the problem of estimating the value of a function from a limited number of data points; and second, the problem of calculating its value from a series approximation. Numerical methods for interpolating and extrapolating data are presented. The famous Lagrange interpolating polynomial is introduced and applied to one-dimensional and multidimensional problems. Cubic spline interpolation is introduced and an implementation in terms of Eigen classes is given. Several techniques for improving the convergence of Taylor series are discussed, including Shank’s transformation, Richardson extrapolation, and the use of Padé approximants. Conversion between representations with the quotient-difference algorithm is discussed. The exercises explore public transportation, human vision, the wine market, and SU(2) lattice gauge theory, among other topics.


Author(s):  
Erin Webster

The Curious Eye explores early modern debates over two related questions: what are the limits of human vision, and to what extent can these limits be overcome by technological enhancement? Today, in our everyday lives we rely on optical technology to provide us with information about visually remote spaces even as we question the efficacy and ethics of such pursuits. But the debates surrounding the subject of technologically mediated vision have their roots in a much older literary tradition in which the ability to see beyond the limits of natural human vision is associated with philosophical and spiritual insight as well as social and political control. The Curious Eye provides insight into the subject of optically mediated vision by returning to the literature of the seventeenth century, the historical moment in which human visual capacity in the West was first extended through the application of optical technologies to the eye. Bringing imaginative literary works by Francis Bacon, John Milton, Margaret Cavendish, and Aphra Behn together with optical and philosophical treatises by Johannes Kepler, René Descartes, Robert Hooke, Robert Boyle, and Isaac Newton, The Curious Eye explores the social and intellectual impact of the new optical technologies of the seventeenth century on its literature. At the same time, it demonstrates that social, political, and literary concerns are not peripheral to the optical science of the period but rather an integral part of it, the legacy of which we continue to experience.


Nature ◽  
1975 ◽  
Vol 254 (5502) ◽  
pp. 692-694 ◽  
Author(s):  
EUGENE LEVINSON ◽  
ROBERT SEKULER
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document