| 摘要 |
PURPOSE:To enable the removal of measuring errors and drift by clamping by attaching a chopper disc with a black body as base between the optical system of an infrared measuring device and a detector. CONSTITUTION:A chopper disc 8 which comprises a black body section 8A coated with a non-reflecting paint and a blank section 8B is attached between an optical system 6 and an infrared detector 7 and then, turned. Infrared rays 5 incident to the infrared detector 7 through the optical system 6 is converted into an AC signal to be inputted into a preamplifier 45 and moreover, it is clamped at the reference level by a clamp pulse 20 formed with a chopper synchronous sensor 30 and a synchronous amplifier 40 in a clamp circuit 50 to remove errors. Then, the clamped output is led through a low-pass filter 60. |
