In this paper, a real time virtual reality camera system for the micro environments has been developed with a dynamic focusing lens and a smart vision sensor using the "depth from focus" criteria.
In the operation with a microscope, such as the micro-surgery, DNA operation and etc., the small depth of a focus makes bad controllability to actuate 3D micro objects with actuators. For example, if the focus is on the object, the actuator could not be seen in the microscope. On the other hand, if the focus is on the actuator, the object could not be observed. In this sense, the "all-in-focus image" is useful for the actuation in micro environments. However, one drawback on the all-in-focus image is that there is no information about the depth of objects. It is also important to reconstruct the micro 3D environments in real time to actuate the object with the micro virtual environments.
This paper discusses the criteria of "depth from focus" to achieve the all-in-focus image and micro 3D reconstruction, simultaneously. Then, a micro VR camera system has been developed to achieve the micro VR environments with the "depth from focus" criteria, i.e. the combination of the all-in-focus image and the micro 3D reconstruction. This system is constructed by a dynamic focusing lens, which can change the focus in high frequency, and a smart vision system, which is capable in capturing and processing the image data in high speed with SIMD architecuture.

View full abstract

Shear stress stripe structure on the wall in turbulent boundary layer has been clearly visualized by a combination of a shear stress sensor using MEMS (Micro-Electro-Mechanical-Systems) and discrete wavelets transform. The MEMS shear stress micro chip is designed and fabricated by surface micro-machining technology, contributing to obtaining the time-space two dimensional shear stress data. One array of 25 micro shear stress sensors in the chip that covers a length of 7.5mm is used to measure the instantaneous spanwise distribution of the surface shear stress. The discrete wavelets transform is a software technique to decompose the frequency level with the time and space information of the wave form. In details, the structure in lower Reynolds number is shown clearly on lower frequency wavelets level, the structure in high Reynolds number is done clearly on higher frequency wavelets level. To visualize and detect the high shear stress area more clearly, the frequency levels are recomposed using the multiresolution filtering effect of wavelets transform. The experiments for the shear stress distribution were carried out on Re=8700 and 17400.

View full abstract

For the development of totally implantable artificial organs, effective monitoring of implantable devices is crucial. In this study, a sensor for a 3-dimensional (3-D) virtual reality (VR) system and micromachine were used to provide such monitoring. The position sensors were attached to the inner actuating parts of the artificial heart system. Using these VR position sensors, we could easily detect the position and movement, and pitch, yaw, and roll. An experimental evaluation was performed using moc circulation loop and healthy adult goats were performed. By the use of chronic animal experiments using healthy adult goats, micro pressure sensors implanted into the cannulae as part of a ventricular assist system were evaluated. The experimental results suggest that our newly developed implantable sensors for monitoring the implantable artificial heart system would be useful for sensing driving condition, and thus for implantable devices for clinical use.

View full abstract

A precise electron interferometry is proposed as a new method to simultaneously visualize an atomic structure and a local electric field. An electron wave which passed through a specimen is overlapped with a reference electron wave to form an interferogram using an electron biprism. Based on a phase shifting interferometry, a precise electron phase distribution can be calculated from at least three intreferograms taken under different interference conditions. The accuracy of the method is discussed through computer simulation. The results show that a phase shift less than 1/100 of an electron wavelength is detectable with a conventional TV system. This value is enough to visualize a single atom and a local electric field simultaneously. A laser interferometer equivalent to the electron case is introduced to clarify the validity of the concept and factors that degrade the accuracy. Measured errors aze Less than 1/60(peak-to-peak)and 1/200(RMS)of the wave-length, respectively. Fresnel diffraction at the biprism, inaccuracy of biprism movement and noise in video signal are revealed to be the most significant problems. Some methods to compensate the errors are also proposed.

View full abstract

Optical probe has the advantage of non-contact sensing and quick response. To combine the optical probe with an optical computerized tomography (O-CT) method, distribution image of space is reconstructed. We have proposed a method for visualizing two-dimensional tomography of ultrasonic beam using schlieren method for data acquisition. The visualized objects are sound fields in the plane which propagated from a circular ultrasonic transducer with a 60-wavelength-aperture at 100, 150 and 200 wavelength. In this paper, schlieren images are used as two-dimensional projection data for the O-CT method without scanning. The visualization system proposed in this paper has advantages using for the environment where the measurement condition changes in order to acquire the data in short time.

View full abstract

The report will focus on visualization techniques related to scanning probe miscoscopy. The topics covered are: (i) visualization of the meandering of a nanometric rubbing surface with subatomic resolution, (ii) positioning using a crystal as the scale reference for accumulation of weak signals without drift, (iii) a nanometric oscillator for detection of small mass and froce, (iv) a scanning probe microscopy operating in a scanning electron microscope, (v) mapping of the subatomic lateral vibration of the scanning probe for imaging of lateral damping and spectroscopy.

View full abstract

The higher supersaturation was achieved by means of the over-heating of growth solution. This method was applied to watersoluble crystal, Deuterated L-A lanine-doped TGS (dLATGS). The dLATGS crystalis a pyroelectric material for the infrared detector which, in general, exhibits one of the highest pyroelectric response of all such materials. The over-heating enlarges the metastable zone during temperature-reducing growing process as a result of eliminating the initial clusters in the mother solution.
A dLATGS crystal (9×2×7cm) was grown with an average rate of 2×2×0.6mm/day (24g/day) in direction of a, -b and c axe s, respectively. This growth rate was several times larger than that of the conventional growth method. The internal bias shown in D-E curves depends on the growth rate of L-Alanine doped crystal of which an uniformity was enough fine to use as an electronic device.
The distribution coefficient of L-Alanine molecule increased with increasing the growth rate.

View full abstract