| 摘要 |
PURPOSE:To eliminate the influence of a background and disturbing ray, by computing the difference of intensity of light of an analysis light source and a spectrum of a central wavelength lambdao of analysis ray of light passing through a light absorption part. CONSTITUTION:Light emitted from an analysis light source 1 is divided into two pieces of light flux by a sector mirror M1 and straight-advanced light is reflected by a sector mirror M2 and then, is made incident to a spectroscope 3. Reflected light is passed through a light absorption part 2 and is advanced to the mirror 2 straight and is made incident to the spectroscope 3. The light of a central wavelength lambdao is emitted from the spectroscope 3 and is made incident to a photodetector 4. Then, the output of said light is amplified by a preamplifier 5 and is inputted into a signal processing circuit 7 through a changeover switch 6. The switch 6 is interlocked to the mirrors M1, M2 and contacts with a contact (a) when the light of the source 1 is made incident to the spectroscope 3 directly and contacts with a contact (c) when the light passes through the part 2 and is made incident to the spectroscope 3. The switch 6 contacts with a contact (b) while transparent parts of the mirror M1, M2 enter a light passage at the same time. The opertion of[input of the contact (a)]+[input of the contact (b)]-[input of the contact (c)]is conducted by the circuit 7. |
