METHOD AND APPARATUS FOR AUTOMATICALLY SWITCHING TEMPERATURE MEASURING RANGE OF INFRARED THERMAL IMAGE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an apparatus for automatically switching the temperature measuring range of infrared thermal image device. ;SOLUTION: A maximum temperature detecting section 1 detects the maximum temperature TP in one frame of thermal image based on a thermal image signal 100. A central processing unit(CPU) 2 averages the maximum temperature TP for eight frames to produce an average maximum temperature TPA. When an intermediate temperature measuring range M is set, the CPU 2 compares the average maximum temperature TPA with the upper limit temperature TM in current temperature measuring range and delivers a switching signal 102a and a drive pulse 102b to a motor drive section 3 if the average maximum temperature TPA the upper limit temperature TM. Rotational direction and angle of a stepping motor can be controlled by the drive pulse 102b. The position of an aperture and a filter coupled directly with the motor shaft is then controlled depending on the rotational direction and angle of stepping motor and the temperature measuring range is switched. The temperature measuring range is switched to high temperature range when TPATM.;COPYRIGHT: (C)1997,JPO