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                                                                    EXHIBIT 23.1

            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the use in this Registration Statement on Form S-1 of our report
dated July 5, 2006, relating to the financial statements of IPG Photonics
Corporation and subsidiaries appearing in the Prospectus, which is part of this
Registration Statement.

We also consent to the reference to us under the heading "Experts" in such
Prospectus.


/s/ DELOITTE & TOUCHE LLP

Boston, Massachusetts
August 11, 2006
