| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily place a beam sensor consisting of a projector and a light receiver at a facing position. SOLUTION: A substrate 2, a control box 3 fixed on the substrate, an optical system housing installed in the control box 3 and an optical system provided in the optical system housing are arranged. The substrate and the optical system housing are molded with dark colored resin and the control box 3 has a color outstanding from black in the constitution.</p> |
