Functional optics of glossy buttercup flowers

Buttercup ( Ranunculus spp.) flowers are exceptional because they feature a distinct gloss (mirror-like reflection) in addition to their matte-yellow coloration. We investigated the optical properties of yellow petals of several Ranunculus and related species using (micro)spectrophotometry and anatomical methods. The contribution of different petal structures to the overall visual signal was quantified using a recently developed optical model. We show that the coloration of glossy buttercup flowers is due to a rare combination of structural and pigmentary coloration. A very flat, pigment-filled upper epidermis acts as a thin-film reflector yielding the gloss, and additionally serves as a filter for light backscattered by the strongly scattering starch and mesophyll layers, which yields the matte-yellow colour. We discuss the evolution of the gloss and its two likely functions: it provides a strong visual signal to insect pollinators and increases the reflection of sunlight to the centre of the flower in order to heat the reproductive organs.

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Changes of UV Optical Properties of Plasma Damaged Low-k Dielectrics for Sidewall Damage Scatterometry

MRS Proceedings ◽

10.1557/proc-1079-n07-04 ◽

2008 ◽

Vol 1079 ◽

Cited By ~ 4

Author(s):

Premysl Marsik ◽

Adam Urbanowicz ◽

Klara Vinokur ◽

Yoel Cohen ◽

Mikhail R Baklanov

Keyword(s):

Thin Film ◽

Optical Properties ◽

Optical Model ◽

Concentration Profiles ◽

Atomic Concentration ◽

Plasma Damage ◽

Tof Sims ◽

Plasma Treatments ◽

Water Based ◽

Low K

ABSTRACTPorous low-k dielectrics were studied to determine the changes of optical properties after various plasma treatments for development of scatterometry technique for evaluation of the trench/via sidewall plasma damage. The SiCOH porogen based low-k films were prepared by PE-CVD. The deposited and UV-cured low-k films have been damaged by striping O2Cl2, O2, NH3 and H2N2 based plasmas and CF4/CH2F2/Ar etching plasma. Blanket wafers were studied in this work for the simplicity of thin film optical model. The optical properties of the damaged low-k dielectrics are evaluated the using various angle spectroscopic ellipsometry in range from 2 to 9 eV. Multilayer optical model is applied to fit the measured quantities and the validity is supported by other techniques. The atomic concentration profiles of Si, C, O and H were stated by TOF-SIMS and changes in overall chemical composition were derived from FTIR. Toluene and water based ellipsometric porosimetry is involved to examine the porosity, pore interconnectivity and internal hydrophilicity.

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Physical and Optical Properties of The Films Ð’i2Te3-Bi2Se3

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v11i2.534 ◽

2015 ◽

Vol 11 (2) ◽

pp. 3017-3022

Author(s):

Gurban Akhmedov

Keyword(s):

Thin Film ◽

Optical Properties ◽

Surface Temperature ◽

Thermal Evaporation ◽

Low Voltage ◽

Internal Surface ◽

Differential Resistance ◽

Work Cycle

Results of researches show, that film p-n the structures received by a method of discrete thermal evaporation in a uniform work cycle, are suitable for use in low-voltage devices.Â As a result of work are received p-n heterojunctions in thin-film execution, described by high values of differential resistance. Show that, thermo endurance - T0 maybe using as characteristic of thermo endurance of optic materials. If heating flow, destruction temperature and internal surface temperature is measured during test, it is possible to determine value T0 and other necessity characteristics. As a result of the taking test was lead to comparison evaluation of considered materials. Working range of heating flow and up level heating embark have been determined.

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