将igs文件导入LT出现以下问题: uHNh|ew21
V|njgcn d
*** Error (AITX_BLANKED_ENTS) *** .R<Ke\y/
5'mpd
The input file did not contain any supported non blanked independant entities. =ll{M{0Q]!
p`CVq `k
Please check the documentation for a list of supported entities. 1/l;4~p7'
d ~`_;.z
请教各位是什么原因,如何解决?