一台早期购进的日本产超声诊断仪出现故障，型号是TokyoKeikiRealTimeUltrasoundSystemLS－300。故障表现为超声图象显示部分亮度差，灰度分辨不清，仅前场半厘米深度有回声信号，中远场调节总增益、近场增益、远场增益均无作用，触压探头时前场部分显示有微弱变化，用金属棒接 An early-stage purchase of a Japanese-made ultrasound diagnostic apparatus failed. The model was the TokyoKeikiRealTimeUltrasoundSystemLS-300. The failure is manifested as the brightness difference of the ultrasound image display part, the grayscale resolution is unclear, only the echo signal is at the depth of half a centimeter in the front field, the total gain of the middle and far field adjustment, the near field gain, and the far field gain have no effect, and the front field is the touch probe. Part of the display shows a slight change and is connected with a metal rod