The physical mechanism of cuticular color in Phelotrupes auratus was investigated by polarized inspection, spectrophotometry and transmission electron microscopy (TEM). No color change was observed when viewed through either a right-or left-handed circular polarizer. Further, under the incidence of linearly polarized light, the reflected intensity was markedly reduced when observed through a linear polarizer set with its optical axis perpendicular to that of the incident light. These results indicate that P. auratus does not possess any circularly polarizing reflectors. TEM observations revealed a total of ten or twelve thin layers (about 60-120 nm in thickness) of two types of material (electron-dense and electron-lucent) alternately stacked in the epicuticle. The thickness of the layers in the different color forms of the beetle corresponded to the peak wavelengths in the reflectance spectra, lmax(a), with thicker layers found in beetles exhibiting reflectance peaks at longer wavelengths and vice versa. Based on these findings, we concluded that all the cuticular color forms of P. auratus were not produced by a circularly polarizing reflector but by a simple multilayer reflector.

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A 0.9” XGA liquid crystal light valve with low temperature Poly‐Si TFT has been developed by using a stacked capacitor structure. The stacked capacitor structure could reduce storage capacitor area because most of the capacitor area is located above the pixel components, such as bus‐lines and TFTs. Therefore, this structure could obtain the required storage capacitance without decreasing aperture ratio. A high aperture ratio of 65% and a high contrast ratio of over 500:1 have been achieved with the fabricated light valve.

An ultrasonic clad steel buffer rod sensor embedded in the die has been used to in-line monitor the die casting process using aluminium alloy billets with semi-solid (thixotropic) and dendritic microstructures as feedstocks. This clad steel buffer rod provided better performance than the previously reported clad zirconium buffer rod. A multiple recording technique was used for the fast data acquisition with a rate up to 0.003 s per acquisition. This single ultrasonic probe monitored the completion of the die filling, the release of the pressure, the opening of the die, part detachment and solidification of the part. The change of the ultrasonic travel time in the clad buffer rod and cast part relates to the variation of the average temperature in the die and part, respectively. The measured amplitude profile of the reflected echo at the probe end/cast part interface can be used to monitor the cold shot and complete filling. The variation of the ultrasonic attenuation coefficient in the cast part may also relate to the change of the composition, microstructure and porosity.