| 摘要 |
PURPOSE:To detect a flame accurately without any malfunction by arranging two parabolic mirrors opposite each other across an infrared-ray band-pass filter and arranging an infrared sensor and a visible light sensor at optically conjugate positions. CONSTITUTION:The two parabolic mirrors 1 and 2 are arranged opposite each other so that their optical axes are aligned with each other. The infrared-ray band-pass filter 3 is installed between the parabolic mirrors while slanted by an angle theta to a plane perpendicular to the optical axes of both parabolic mirrors. Then, an incidence window 4 for light is formed at the focus position of the 1st parabolic mirror 1 and the infrared sensor 5 is installed at the focus position of the 2nd parabolic mirror 2 while the visible light sensor 6 is arranged where light reflected by the infrared-ray band-pass filter 3 is converged. Consequently, light from a flame and disturbing light are incident on both sensors 5 and 6 in parallel, so no malfunction is caused. |
