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Tapered glass capillary optics was utilized to produce MeV ion microbeams at the RIKEN Pelletron facility. A microbeam of 3 MeV He ions was used to irradiate HeLa cells and demonstrated an ion track consisting of double strand break points in the cell nucleus. A new microbeam line was developed with profile measurements of 2.8 MeV H+ microbeams in the atmosphere, using image recognition and knife-edge methods. After the suppression of the halo component in the microbeam, a smaller beam size was measured to be approximately 40 μm for the irradiation distance of 1 mm, which satisfied requirements of the planned applications.

We measured laser microbeam (18 µm) profiles of tilted glass capillary at wavelength 375 nm. The profile intensity, width and beam guided angle were obtained and results show guiding effect of the capillary optics.

The transmission of an ultraviolet-laser microbeam through a tapered glass capillary was investigated. We measured microbeam profiles using fluorescent beads and obtained smaller spots for smaller ...

Microbeams of visible light were studied using a tapered glass capillary. Transmittance of laser light through capillaries with different inlet and outlet diameters was measured. About several % of the transmittance was obtained and larger than 80% was achieved in combining with an optical lens. It was found that the obtained transmittance considerably depended on the capillary shape, i.e., the taper angle. Density enhancement of the extracted beam was derived and showed a strong focusing ability for the tapered glass capillary. Propagation of visible light through the capillary was discussed.

Propagation and transmission of laser beam through tapered glass capillary were investigated for light microbeams. Transmittances of laser light at 488 nm and 633 nm through capillaries were measured to be up to 15%, depending on outlet diameters. By modeling the real capillary, transmittances were calculated using taper angles obtained from shape analysis and agree well with experimental ones.

An estimation method of micro-meter sized laser profile created by the laser beam transmission through a tapered glass capillary is developed for the target sight-on system of ion microbeam irradiation to living cells. In our system, both the laser and the ions are designed to be transmitted through the same capillary so that the laser spot is surely on the ion track. By selecting the excitation light of a fluorescent protein in cell nucleus, the fluorescent volume can be confirmed as the targeted area.

Recently, many studies have been reported on microbeam production of keV-MeV accelerated ions using tapered glass capillaries. However, few studies about visible light with the glass capillary have been reported up to now. Preferable sizes of microbeams can be obtained by the glass capillary which may provide a new method for focusing light and for producing microbeams of visible light in addition to conventional optical lenses. We report experimental study of propagation of visible light through tapered glass capillaries towards microbeams.

Towards production of microbeams, propagation of visible light through a tapered glass capillary has been studied. Transmittance has been measured for capillaries with different outlet diameters to be about several % and larger than 80% has been achieved in combining with the optical lens. Density enhancement of the capillary has been derived, showing the strong focusing ability of the tapered glass capillary.

The transmission of a laser beam through a tapered glass capillary was investigated both experimentally and theoretically for light microbeams. The transmittances of laser light at 488 and 633 nm through capillaries were measured to be up to 15%, depending on the outlet diameter. By characterizing a real capillary with precise measurement of the whole capillary geometry, a realistic simulation allowed us to calculate the transmittance. By using a Gaussian profile as the input beam in a simulation, the calculated transmittances well reproduced the experimental ones. The density enhancement of the extracted beam was derived and discussed.

Towards production of microbeams, propagation of laser beams of visible light with wavelengths of 488, 633 and 670 nm through tapered glass capillaries has been studied. In conjunction with an optical lens upstream of the capillaries with outlet sizes ranging from 17 to 100 μm, transmission efficiency more than 80% has been achieved for outlet diameters more than 40 μm

The high-resolution ultraviolet (UV) laser spectroscopy of 27Al has been performed by the frequency doubling of a tunable diode-laser beam together with a collimated atomic beam. Hyperfine structure spectra have been observed for two UV transitions in Al I, namely, 3s23 p2P1/2–3s24s2S1/2 at 394.401 nm and 3s23 p2P3/2–3s24s2S1/2 at 396.152 nm. The hyperfine structure constants A and B of 27Al have been determined for the 3s23 p2P1/2,3/2 and 3s24s2S1/2 levels, and compared with previously reported results.