Abstract: A coating film capable of attaining excellent corrosion resistance which is provided with both the first coat formed on a member having a metal surface by heating the first coating composition which comprises, based on the whole composition, 5 to 40% by mass of an organosilicon compound, 0.05 to 5.0% by mass of an organotitanate compound, 20 to 60% by mass of one or more metal powders selected from the group consisting of zinc powder, zinc alloy powders and aluminum powder, and 10 to 60% by mass of an organic solvent in such a way to cover the surface including the metal surface and the second coat formed on the first coat by heating the second coating composition which is an aqueous one comprising, based on the whole composition, 5 to 16% by mass of a silane coupling agent and 30 to 60% by mass of an alkali silicate.

Abstract: An optical measuring device capable of improving the precision of detection of contamination on a protective glass is disclosed. With threshold values as large as 90%, 50%, 10% of a peak value of a scan signal, measured values Q90, Q50, Q10 of a dimension of a work to be measured are derived, respectively. It is determined whether a difference between the measured value Q90 and the measured value Q50 (or a variation of the measured value) is equal to or larger than a predetermined reference value. (B)-(D) show the presence of contamination on the protective glass, equal to or larger than the reference value. (A) shows the absence of contamination, lower than the reference value. It is then determined whether a difference between the measured value Q50 and the measured value Q10 is equal to or larger than a predetermined reference value. (D) shows the presence of thick contamination on the protective glass, equal to or larger than this reference value.

Abstract: An optical measuring device wherein a workpiece being measured is interposed between a parallel scanning ray beam generating source and a light receiving element, and dimensions of the workpiece being measured is measured from the time length of a dark portion or a bright portion generated due to the obstruction of the parallel scanning ray beams by the workpiece being measured. The aforesaid parallel scanning ray beam generating source comprises: a beam generator; a rotary mirror for reflecting and converting the incident ray beams into rotary scanning ray beams; a ray beam transmitting mechanism for dividing the ray beams from the beam generator in terms of time or quantity and causing the ray beams thus divided to incide into the rotary mirror at a predetermined incident angles; and a collimator lens for converting the rotary scanning ray beams from the rotary mirror into parallel scanning ray beams.