Our company is a well-known company in the POS system industry.Is this correct?Is this correct?Our company is a well-known company in the POS system industry

Our company is a well-known company in the POS system industry.Is this correct?Is this correct?Our company is a well-known company in the POS system industry
Our company is a well-known company in the POS system industry.Is this correct?
Is this correct?
Our company is a well-known company in the POS system industry

Our company is a well-known company in the POS system industry.Is this correct?Is this correct?Our company is a well-known company in the POS system industry
Our company is well-known in the POS system industry.

介词in 用错了。。用of 合适啊。

正确

虽然语法上不能说有问题，不过这个说法不太符合英文表达的习惯。
这样也许更好一点：
Our company is a well-known POS system manufacturer.