将igs文件导入LT出现以下问题: E`J@hl$N
7$#u
*** Error (AITX_BLANKED_ENTS) *** 4e
BLFdHB.$T
The input file did not contain any supported non blanked independant entities. ^?|"L>y
5twhm
Please check the documentation for a list of supported entities. MOC/KNb
V~#tuv
请教各位是什么原因,如何解决?