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                                                                    EXHIBIT 23.1

            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the use in this Amendment No. 1 to Registration Statement No.
333-136521 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 such Registration Statement, and to the reference
to us under the heading "Experts" in such Prospectus.


/s/ DELOITTE & TOUCHE LLP
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Boston, Massachusetts
September 27, 2006
