| 摘要 |
PURPOSE:To quantitatively measure the freshness of plants simply, by utilizing a photosynthetic reaction thereof. CONSTITUTION:A measuring light from a measuring light source 3 reaches a photo detector 1 passing through a sample 2. A long-wavelength light from a light source 4 irradiates the sample while a short-wavelength light from a light source 5 does it. Upto the time 7, light of a fixed intensity enters the photo detector. The reaction line upto the time is called as base line. As the irradiation of the long-wavelength light starts at the time 7, the light transmittance decreases to reach a fixed value but when the short-wavelength light irradiates together therewith at the time 8, the light transmittance increases to reach a fixed value. Following the time 8, it depends on the intensity of the short-wavelength light how the reaction line rises if the intensity of the long-wavelength is constant and the reaction line will reach the height of the base line when the short-wavelength light is intense. The ratio between intensities of the long- and short-wavelength lights indicates the value proportional to the freshness. |
