| 摘要 |
PURPOSE:To measure the dust concentration with high accuracy by measuring the optical diffusion intensity of >=two kinds of wavelengthes for the main component of the dust and by measuring the dust concentration based on the optical diffusion intensity value thereof and the relative equation of the optical diffusion intensity and dust concentration. CONSTITUTION:A light emitting part 11 has two light source parts 15, 16 and is made to irradiate the light from the lamps 15, 16 onto a suction pipe via a condensing lens 19. This light in two kinds of wavelength irradiated from the lamps 15, 16 is partially diffused with reflection respectively by the dust inside the suction pipe and those diffused light beams are led to a photodetecting part 12. The photodetecting part 12 incorporates the optical detecting sensor 17 having detecting sensibility for the two kinds of wavelengths on the optical path of the diffusion light and a condensing lens 19' at the light incident side thereof, and the respective diffusion light of two wavelengths is caught by the sensor 17 as the electrical signal of optical diffusion intensity L1, L2, which are outputted to a computing element 30, and the dust concentration is calculated by the input signal L1, L2 and the prescribed equation at the computing element 30. In this way the dust concentration can be measured with high accuracy even in case of the color varying with the change in the ratio of the dust main components. |
