[1] ALYCE M H.Remote visual inspection equipment for quality control[J].Medical and Industrial Equipment,2001,6:214-216.

[2] MIZUNUMA M,OGAWA S,KUWANO H.Deformation detection on the pipe inner wall using a laser-beam scanning displacement sensor[J].SPIE,2066,93:98-105.

[3] ROBERT W,MCCLLOUGH R W,BONDURANT P D,et al.Laser-optical triangulation systems provide new capabilities for remote inspection of interior surface[J].Materials Evaluation,1995,53(12):1338-1345.

[4] INARI T,TAKASHIMA K,WATANABE M,et al.Optical inspection system for the inner surface of a pipe using detection of circular image projected by a laser source[J].Measurement,1994,13(2):99-106.

[5] Zhang W W,Zhuang B H.Non-contact laser inspection for the inner wall surface of a pipe[J].Meas.Sci.Technol,1998,9(9):1380-1387.

[7] KE Y L,GUO T,LI J X.A new-style slotted_cymbal transducer with large displacement and high energy transmission[J].IEEE transaction on ultransonics,ferroelectrics and frequency control,2004,51(9):1171-1177.