| 摘要 |
PURPOSE:To enhance the measuring accuracy of a thermometer by perfectly eliminating a mechanical operation part, by blocking infrared rays allowed to irradiate a pyroelectric element from an object to be measured by a liquid crystal plate in a time sharing manner. CONSTITUTION:Because a liquid crystal plate 1 repeats a transparent state and an opaque state at several cycles per a sec by the control signal from a liquid crystal plate control part 3, a pyroelectric element 2 is irradiated with infrared rays at every constant cycle. Therefore, a signal corresponding to the change component in the irradiation quantity of infrared rays is outputted from the pyroelectric element and receives full-wave rectification and smoothing in a temp. detection part 4 while the smoothed signal is outputted as a temp. display signal. Thus constituted infrared temp. sensor has no mechanical operation parts at all and the possibility of the lowering in the measuring accuracy of a thermometer caused by friction or strain is eliminated. |
