Patent ID: 7569012

Claim:
An ultrasonic endoscope comprising: an insertion portion comprising a distal hard portion which includes an endoscopic observation unit arranged within the distal hard portion so as to include an observation field of view that extends distally from a distal end of the distal hard portion with a predetermined viewing angle in an axial direction of the distal hard portion; an ultrasonic observation unit that includes a predetermined number of ultrasonic transducers arranged circumferentially on an outer circumferential section of the distal hard portion and having a circular or arcuate scanning range, wherein the ultrasonic observation unit comprises an ultrasonic-wave transmission/reception unit that includes a backing layer on an inner circumferential surface such that the backing layer defines an approximately cylindrical tunnel-shaped path; and a distal block arranged on a distal side of the distal hard portion in the axial direction of the distal hard portion with respect to a location where the ultrasonic-wave transmission/reception unit is arranged on the distal hard portion, wherein the endoscopic observation unit is arranged in the distal hard portion such that the endoscopic observation unit passes through the tunnel-shaped path and a distal end portion of at least one optical member of the endoscopic observation unit is fixed to the distal block such that an outer circumferential portion of the distal end portion of the at least one optical member of the endoscopic observation unit protrudes, in the distal block, beyond an inside diameter of the tunnel-shaped path defined by the backing layer toward an outer circumferential side of the distal hard portion in a radial direction of the distal hard portion.