Influences of misalignment errors of optical components in an orthogonal two-axis Lloyd's mirror interferometer.

This paper presents a detailed analysis on the influence of misalignment errors of optical components in an orthogonal two-axis Lloyd's mirror interferometer, which can fabricate two-dimensional grating structures in a single exposure. In an ideal condition, defect-free two-dimensional grating structures can be fabricated by the interferometer. However, in a real case, visible stripes caused by misalignment errors of the optical components in the interferometer always appear on the fabricated grating structures. In this paper, theoretical analysis and experiments are carried out to analyze the influences of the misalignment errors of the optical components in the orthogonal two-axis Lloyd's mirror interferometer.

Mode-locked laser autocollimator with an expanded measurement range.

A mode-locked laser is employed as the light source of a laser autocollimator, instead of the conventionally employed single-wavelength laser, for an expanded range of tilt angle measurement. A group of the spatially separated diffracted beams from a diffraction grating are focused by a collimator objective to form an array of light spots on the focal plane of the collimator objective where a light position-sensing photodiode is located for detecting the linear displacement of the light spot array corresponding to the tilt angle of the reflector. A prototype mode-locked femtosecond laser autocollimator is designed and constructed for achieving a measurement range of 11000 arc-seconds.

Ultra-sensitive angle sensor based on laser autocollimation for measurement of stage tilt motions.

An ultra-sensitive angle sensor employing single-cell photodiodes, which allows tighter focusing leading to a higher angular resolution better than 0.001 arc-second, has been designed based on laser autocollimation. Aiming to investigate the influences of spherical aberrations in the optical system on the sensor sensitivity, an optical model has been established based on wave optics. Computer simulation has been carried out by using the model, and its feasibility has been verified in experiments. In addition, a prototype optical angle sensor has been designed in a compact size of 100 mm × 150 mm, and its measurement resolution has been verified in experiments.

Design of a new dental adhesive--effect of a water-soluble sodium acylphosphine oxide with crown ether on adhesion to dental hard tissues.

The behavior of water-soluble photoinitiators with crown ethers in dental adhesives is unknown. This study investigated the effect of sodium acylphosphine oxide (APO-Na) with crown ether in a hydrophobic adhesive on adhesion to teeth. Sodium 2,4,6-trimethylbenzoyl-phenylphosphine oxide (TMPO-Na = APO-Na) was synthesized in 67.1% yield and identified by 1H NMR. APO-Na was dissolved in hydrophobic resins in the presence of a crown ether (ionophore effect). Thirty kinds of experimental single-step adhesives comprising APO-Na, CE, Bis-GMA, 6-methacryloyloxyhexyl phosphonoacetate (6-MHPA), and 4-methacryloyloxyethyl trimellitic acid (4-MET) were thereby prepared. Shear bond strength to unetched ground teeth was measured at a crosshead speed of 1.0 mm/min, and the data were analyzed by ANOVA. The shear bond strength results of bonding resins containing APO-Na with 18-crown-6-ether (CE-6) were significantly higher than that without CE-6 (control) (p<0.05). Higher bond strength values [for enamel: BR24 at 19.3 (3.2) MPa; for dentin: BR29 at 20.2 (4.7) MPa] were achieved with the adhesives containing APO-Na, CE-6, 6-MHPA, and 4-MET. Therefore, it was found that APO-Na with CE-6 contributed to the efficient bonding performance of single-step adhesive to teeth. However, in view of the biosafety hazard posed by crown ethers, the search is still on for reagents that are biologically safer than crown ethers--but with ionophor effects--to be used in dental adhesives.

UV-VIS spectra and photoinitiation behaviors of acylphosphine oxide and bisacylphosphine oxide derivatives in unfilled, light-cured dental resins.

The aims of this study were to investigate the photoinitiation behaviors of acylphosphine oxide (APO) and bisacylphosphine oxide (BAPO) derivatives in comparison to D,L-camphorquinone (CQ)/tertiary amine (EDAB) system. Fifty six kinds of experimental unfilled, light-cured resins were prepared using APO, BAPO, CQ, EDAB, resin monomers, and adhesive monomers. The measurements of ultraviolet-visible (UV-VIS) spectroscopy, photopolymerization with differential scanning calorimeter (photo-DSC) and degree of conversion (DC) determination were performed. Results showed that the UV-VIS spectra of all APO and BAPO derivatives possessed lambda max ranging between 365 and 416 nm. Their photoinitiation behaviors were not influenced by acidic adhesive monomers formulated in unfilled Bis-GMA-based resins (p < 0.05). Although BAPO exhibited higher reactivity than CQ/EDAB in unfilled 6-methacryloyloxyhexcyl phosphonoacetate (6-MHPA)/ 2-hydroxyethyl methacrylate (HEMA) and 6-MHPA/glycerol monomethacrylate (GM)-based resins, it was found that there were no statistically significant differences in DC (%) between BAPO [44.2(6.5)-51.2(4.3)] and CQ/EDAB [42.4(4.4)-47.5(3.7)] (p < 0.05). It was concluded that APO and BAPO photoinitiators exhibited reactivity comparable to that of CQ/tertiary amine system.

Effect of Saiko-ka-ryukotsu-borei-to on amylase activity in mice.

The effects of Saiko-ka-ryukotsu-borei-to (SRBT), a Chinese medicinal prescription, on mouse serum amylase activity were investigated in vivo. SRBT was found to not only dose- and/or time-dependently augment amylase activity, but also to increase alpha-amylase protein content and soluble starch metabolic activity. These results provide a rational basis for the clinical use of SRBT that may accompany disease therapy.