Jisuke Fukaya

Miniature robot with micro capillary capturing probe

A micro capillary capturing probe which is based on surface tension of water is described. This probe is composed of a capillary of glass, small solenoids and a micro magnetic piston. The quick reciprocating motion of the magnetic piston, which is accelerated by the solenoid current, can push and pull the water in the capillary. At the end of the capillary, the water drop can grow to reach the small object on the surface, contain it with help of surface tension and retract it into the capillary. The simple principle and design are discussed and the experimental results of capturing small objects are demonstrated. This active probe has been successfully implemented into our miniature precise robot for surface clearing operation.

Scanning Tunneling Microscopy and Barrier-Height Observation of Stearic Acid Thin Films Prepared by Hot-Wall Technique

Stearic acid thin films prepared by the hot-wall technique have been observed and barrier heights () have been measured using scanning tunneling microscopy (STM), which is operated in air. Three kinds of substrates are used to prepare stearic acid films: highly oriented pyrolytic graphite (HOPG), gold thin film and indium-tin-oxide (ITO) film. X-ray diffraction analysis reveals that molecules in films are oriented normal to the substrate. The thickness of films we used is about 30 nm. Using STM and images of films, we confirmed that the film surface morphology varies with the kind of substrate. Islands of stearic acid are sparsely formed on the HOPG and gold thin film substrates; however, in the case of the ITO substrate, small islands (about 3 nm) nearly cover the entire substrate surface. Under certain circumstances, it is more effective to observe the stearic acid morphology in terms of values of with the STM images in the constant-current mode.

Fraunhofer diffraction of a slit aperture between a knife-edge and a metal cylinder

The Fraunhofer diffraction pattern of a slit aperture formed between a reference knife-edge and a metal-cylinder surface is different from that of an ideal slit aperture. This pattern should include reflected light coming from both the front and rear sides of a cylinder surface. To investigate the influence of light reflected from the cylinder surface, we discuss the theoretical consideration based on the simple model of the reflected light on the surface. The experimental setup is designed and constructed to measure the actual diffraction pattern produced by the slit between the knife-edge and the cylinder surface. As a result it is obvious that the reflection of diffracted light on the rear side is dominant in both the simulation and the experiment.

Navigation and formation control for distributed miniature robots with micro tool and sensor

Multiple miniature robots with simple micro tool and sensor can provide great cost saving benefits particularly with an ultra precise manufacturing process. In our project, several miniature robots with reliable performance even in microscopic ranging are to be employed and managed for giving collaborative operation applicable to microfabrication. Graphical on-line simulation with a parallel processing facility is developed to check out the feasibility of initial plan and decision making for navigation and formation control of multiple miniature robots.

High-Efficiency Bridge Double Phase-Conjugate Mirrors in Cu-Doped (K0.5Na0.5)0.2(Sr0.61Ba0.39)0.9Nb2O6 Crystals

In this paper, we report the formation of high-efficiency double phase-conjugate mirrors with the bridge incident geometry in Cu-Doped (K 0.5 Na 0.5 ) 0.2 (Sr 0.61 Ba 0.39 ) 0.9 Nb 2 O 6 (Cu :KNSBN) crystals. These bridge double phase-conjugate mirrors have high efficiency, even under low incident power. For crystals with different absorption coefficients, the optimum incident geometries of the bridge double phase-conjugate mirrors were observed and discussed.

Scanning tunneling microscopy combined quartz crystal microbalance for study of NH3 adsorption on Ag thin film

Abstract Scanning tunneling microscopy for the observation of the surface topography and quartz crystal microbalance for the micro mass measurement of the thin film have been combined to investigate the morphology change of the surface of Ag thin film. Ag is evaporated on the surface of the AT-cut quartz crystal which is oscillated at the resonance frequency. The mass change for the adsorption or the desorption results in a shift in the resonance frequency. Thus the mass of the adsorption or the desorption can be measured by detecting the frequency shift of the quartz crystal oscillator. In situ morphology and mass changes as little as 320 ng cm−2 in the NH3 adsorbed process on Ag surface are observed by the combined system of the scanning tunneling microscopy and the quartz crystal microbalance.

Double phase-conjugate mirrors in KNSBN:Cu crystal

In this study, we investigate the formation and performance of the double phase-conjugate mirrors in KNSBN:Cu crystal. In a KNSBN:Cu crystal, we formed the bird-wing, the bridge and the modified-bridge double phase-conjugate mirrors. Experimental results show that these double phase-conjugate mirrors have the high performance.

Phase-Conjugate Imaging Properties in High-Efficiency KNSBN:Cu Double Phase-Conjugate Mirror

In this study, we investigate the performance of a high-efflciency KNSBN:Cu double phase-conjugate mirror (DPCM). A phase-conjugate transmissivity as high as 58% and a phase-conjugate reflectivity as high as fivefold are observed. Experimental results also show that the DPCM has a good fidelity of phase-conjugate image. Also, amplified phase-conjugate images are observed.

Microstructure‐image enhancement by scanning photoacoustic microscopy

Enhancement of the piezoelectric‐photoacoustic signal from surface microstructures is achieved by the contact with silicone oil.

Measurement of Specular Reflectance using a Single Slit.

This paper deals with a new measuring method of specular reflectance of a plane surface using a single slit. Illuminating light and its light reflected at the surface are incident on the slit simultaneously. A ratio of second to first peak intensity of the diffraction pattern formed by the slit is proportional to the reflectance of the plane surface. An angle of incidence is variable from 80°up to 89°with the slit of width 100μm. It is possible to measure a small surface of 18 mm 2 at 89°. The measurements of reflectance are carried out with some specimens using a linearly polarized light. The measured reflectance R s and R p of Optical flat(Quartz, flatness λ/10, nd=1.4538) agree well with those of calculated by Fresnels formulae. This method is applicable to the measurement of the surface roughness and the glossiness of low reflectivity.