| 摘要 |
PURPOSE:To safely and surely insert the endoscope into a tube cavity internal organ, and also, to obtain an ultrasonic image over a wide range by providing at least two front diagonal view optical systems in the vicinity of the rear end of an ultrasonic transmitting/receiving window so as to compensate the respective dead angles. CONSTITUTION:As for a tip part 8 of an inserting part 3 of an ultrasonic endoscope, a base part 10 is in a cylindrical state whose diameter is a little larger than a tip hard part 11, the tip hard part 11 of a thin diameter has an ultrasonic transmitting/receiving window 12, and between the rear end of the tip hard part 11 and the front end of the base part 10, a V-shaped groove is formed extending over the whole outside periphery, and on the groove forming surface of the base part 10 side, two objective optical systems 14, 15 are provided on 180 deg. symmetrical positions of the up-side and the down-side of the endoscope positioned on the diameter line of the base part 10. Also, on two objective optical systems 14, 15, a roughly semicircular mask is provided so as to cover in advance the part brought to missing by the tip hard part 11. The visual field direction from the objective optical systems 14, 15, respectively is the front diagonal view direction, and in the respective visual field ranges, the tip hard part 11 is eliminated, and also, since the up-side and the down-side of the endoscope can be observed simultaneously extending over a wide range, the inserting direction of the inserting part can be confirmed visually over a wide range. |
