| 摘要 |
PURPOSE: To avoid the infection of germs or a pollutant from a patient to an instrument and/or from the instrument to the patient by installing a partially transparent window for rays of light within the range of a specified wave length at the closing end portion of a coating member. CONSTITUTION: In an illuminating tool 1 for a dental surgery or a retractor, a coating member 3 consisting of a polyethylene foil covers an optical conductor rod 4 which is useful as a light discharging member. In this case, a part of the polyethylene foil is directly laid on the light discharging surface 5 of the optical conductor rod 4. The slipping down of the coating member 3 from the optical conductor rod 4 is prevented by an O-ring 6. A window 10 made of a non-deformable silicon boric acid glass is arranged at the closed end portion of the coating member 3. The window is formed by an optical filter which is opaque for a light within the range of a wavelength of less than 370nm in order to avoid the radiation of ultra violet ray, particularly, a UVB-radiation (i.e., with a range of 280-320 nanometers) of a short wave length at the treating place. |
