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                                                                   Exhibit 10.16

                               LASERTECHNICS, INC.
                              3208 COMMANDER DRIVE
                             CARROLLTON, TEXAS 75006


                                                               December 29, 1997

Amphion Ventures L.P. ("Ventures II")
Antiope Partners L.L.C. ("Partners")
c/o Jackson Hole Management Company
590 Madison Avenue, 32nd Floor
New York, New York  10022

J.P. Morgan Investment Corporation ("JPMIC")
60 Wall Street
New York, New York  10260

                 AMENDMENT TO NOTES AND NOTE PURCHASE AGREEMENT

Dear Sirs:

                  This letter sets forth certain amendments to (i) the Note
Purchase Agreement dated as of June 25, 1997 (the "Original Note Purchase
Agreement"), among Lasertechnics, Inc., a Delaware corporation (the "Company"),
Antiope Partners L.L.C. (formerly, Wolfensohn Partners, L.P.) ("Partners") and
J.P. Morgan Investment Corporation ("JPMIC"), which Note Purchase Agreement was
assigned by Partners to Amphion Ventures L.P. (formerly Wolfensohn Associates II
L.P.) ("Ventures II") by Assignment Agreement dated as of August 19, 1997 and
(ii) the several Senior Promissory Notes issued and sold by the Company pursuant
to the Original Note Purchase Agreement. Capitalized terms used herein and not
otherwise defined are used as defined in the Original Note Purchase Agreement,
as modified and amended herein.

                  NOW, THEREFORE, in consideration of the mutual agreements
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto, intending to
be bound hereby, hereby agree to amend the Original Note Purchase Agreement, the
Senior Promissory Notes and the Pledge Agreement, as follows:


                  1. EXTENSION OF FINAL MATURITY DATE. The Final Maturity Date 
under the Note Purchase Agreement and each of the Senior Promissory Notes is
hereby extended to December 31, 1998, for all purposes of the Note Purchase
Agreement, the Senior Promissory Notes and the Pledge Agreement, except as
expressly provided in paragraph 2 of this Amendment to Note Purchase Agreement.



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Lasertechnics, Inc.
Amendment to Note Purchase Agreement
Page 2 of 10

                  2. ADDITIONAL CONSIDERATION. Notwithstanding the extension of 
the Final Maturity Date as provided herein, on December 31, 1997, the Company
shall pay and deliver to each registered holder of the Senior Promissory Notes
the additional consideration provided for in paragraph 7 of the Original Note
Purchase Agreement, with respect to any and all Senior Promissory Notes
outstanding on such date.

                  3. RIGHT TO EXCHANGE NOTES. The exchange right set forth in
paragraph 9 of the Original Note Purchase Agreement is hereby terminated, and
the Original Note Purchase Agreement is hereby amended to delete such paragraph
9 in its entirety.

                  4. INTEREST RATE. The Senior Promissory Note issued to JPMIC
is hereby amended to increase the Base Interest Rate thereunder from 6.64% per
annum to 10.00% per annum, effective January 1, 1998. The Base Interest Rate
payable under the Senior Promissory Note(s) issued to Partners and/or Ventures
II will remain at 10.00% per annum.

                  5. MISCELLANEOUS. (a) Except to the extent modified and
amended herein, the terms and provisions of the Original Note Purchase
Agreement, Senior Promissory Notes and Pledge Agreement shall remain in full
force and effect as originally executed. All references in the Senior Promissory
Notes, the Pledge Agreement or any other instrument or agreement to the Note
Purchase Agreement shall be deemed for all purposes to refer to the Note
Purchase Agreement as amended hereby.

                  (b) This Amendment and the amendments and modifications
provided for herein shall be binding upon and inure to the benefit of the
parties hereto and their respective successors and permitted assigns.

                  (c) This Amendment may be executed in any number of
counterparts and on separate counterparts, each of which shall be an original
instrument, but all of which together shall constitute a single agreement. One
or more signature pages from any counterpart of this Amendment may be attached
to any other counterpart of this Amendment without in any way changing the
effect thereof.



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                  If the foregoing correctly sets forth your understanding of
our agreement, please so indicate by signing and returning to the Company the
enclosed counterpart of this Amendment.

                                            Very truly yours,

                                            LASERTECHNICS, INC.


                                            By: /s/
                                               ---------------------------------
                                               Name:
                                               Title:


Each of the undersigned agrees with and 
accepts the foregoing terms and provisions 
as of the date first above written.

AMPHION VENTURES L.P.
By:  Amphion Partners L.L.C., its general partner


     By: /s/
        -----------------------------------------
         Managing Member


ANTIOPE PARTNERS L.L.C.


     By: /s/
        -----------------------------------------
         Managing Member


J.P. MORGAN INVESTMENT CORPORATION


     By: /s/
        -----------------------------------------
         Name:
         Title: