• Journal of KIISE:Computer Systems and Theory
• /
• v.37 no.3
• /
• pp.184-193
• /
• 2010

This paper proposes a biological iridescence BRDF(Bidirectional Reflectance Distribution Function) compression and rendering method. In the graphics technology, iridescence sometimes is named structure colors. The main features of these symptoms are shown transform of color and brightness by varying viewpoint. Graphics technology to render this is the BRDF technology. The BRDF methods enable realistic representation of varying view direction, but it requires a lot of computing power because of large data. In this paper, we obtain reflection map from iridescence BRDF, analyze color of reflection map and propose representation method by several colorfully concentric circle. The one concentric circle represents beam width of reflection ray by one normal vector. In this paper, we synthesize rough concentric by using several virtually optical normal vectors. And we obtain spectrum information from concentric circles passing through the center point. The proposed method enables IBR(image based rendering) technique which results is realistic illuminance and spectrum distribution by one texture from reduced BRDF data within spectrum.

• Journal of the Optical Society of Korea
• /
• v.18 no.5
• /
• pp.616-622
• /
• 2014

Specular structural colors generated by two-dimensional periodic binary gratings are investigated theoretically. An approximate mathematical model of the grating specular structural colors is described, based on scalar nonparaxial diffraction theory, and the functional relationships of specular structural color and structural parameters of gratings are analyzed. Through this, the optimal condition for maximizing the color-representation range in the standard CIE 1931 chromaticity diagram is derived.

• ALGAE
• /
• v.29 no.1
• /
• pp.1-13
• /
• 2014

The genus Erythroglossum is characterized by Phycodrys-type apical organization, Polyneura-type procarp, and the presence of a midrib. We collected an unidentified Delesseriaceaen species from deep water off the southern coast of the Korean Peninsula. This alga resembles Polyneura japonica in terms of having broadly flattened thalli with a cylindrical stipe, the presence of a midrib and alternative lateral veins. To confirm the taxonomic status of this entity, we compared the morphological features and rbcL sequences among other species of Erythroglossum and P. japonica. As a result, we assigned the new species, Erythroglossum hyacinthinum, to the genus Erythroglossum because of the presence of a midrib. This species is characterized by an elliptical to obovate blade with a short cylindrical stipe, a conspicuous midrib and alternate veins, margins with numerous microscopic dentations, di-trichotomously branching, and bulish-violet iridescence. The phylogeny of rbcL sequences indicates that E. hyacinthinum is definitely a separate entity, but the genera in the tribe Phycodryeae have inconsistent phylogenetic relationships. This is the first study comparing the molecular phylogeny within the genus Erythroglossum.