| 摘要 |
PURPOSE:To evaluate the divided area of ferroelectric and to enable to discover the defect of boring safely and surely by the simple method, by a method wherein patterns which are generated when electrified fine powders are electrostatical attached to the surface of the ferroelectric which are divided to single areas, are observed. CONSTITUTION:Electrified fine powders are electrostatically attached to the ferroelectric which are divided to single areas, and them divided areas of ferroelectric are evaluated from the distribution condition of attached powders. As for ferroelectric which is possible to evaluate the divided area, there is a piezoelectric single crystal having a polar axis, for instance, LiNbO3, LiTaO3 etc. As for powders used, if they are powders to present different color tones by ground color of specular polished strong dielectric, ultraviolet light irradiation, or at the condition as they are, any powder which is possible to be charged will be suitable. As for powders which emit light by ultraviolet light irradiation, there are, for instance, zincoxide, zinc sulfide etc. and as for powders other than fluorescent substance there are silicon dioxide, alumina etc. As for these powders, fine powders of mean particle diameter 1-30mum are adequate, and when to attach powders it is desirable to heat ferroelectric to the temperature under 150 deg.C. |
