Photoisomerization has been recently studied in the various area of industry. A field of molecular motor and an optical memory with nanotechnology, for example, has been especially made progress acutely and hold the promise of the application to various industries. In our laboratory, photo functional materials using photochromic molecules with ultraviolet (UV) and visible (visible) laser has been studied and developed. Photochromic molecules are isomerized to absorb specified wavelength light and its property of the molecular structure changes reversibly by light.
For a efficient isomerization, the high energy density light is necessary in large number of photochromic molecules.
On the other hand, the laser beam is enable to focus on the several hundred nanometer range, it is possible to isomerize at the only several decades piece unit in the photochromic molecule, because the average of molecule length of the photochromic molecule is several nanometer. In this experiment, it has been UV (wavelength 355nm, pulse duration 5ns) and visible (wavelength 532nm, pulse duration 8ns) laser with 50Hz pulse repetition frequency for measuring the ratio of isomerized molecules from fluctuating absorption wavelength by laser irradiation. As a result, it is considered that the probability in the excited molecule is a increases using laser to irradiate the molecule, the number of photon that collides per molecule have been increased on the increasing irradiation time. In conclusion, it is suggested that microdevices to control submicroscopically have been constructed by combination of photochromic molecule and UV-visible laser.