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                                                                   EXHIBIT 10.77



                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT

                  THIS FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT (the
         "First Amendment") is by and among FLEET NATIONAL BANK, a national
         banking association having an office located at 370 Main Street.
         Worcester, Massachusetts 01608, (the "Lender"), SPECTRAN CORPORATION, a
         Delaware corporation with a principal place of business at 50 Hall
         Road, Sturbridge, Massachusetts ("SpecTran"), SPECTRAN SPECIALTY OPTICS
         COMPANY, a Delaware corporation with a principal place of business at
         150 Fisher Drive, Avon, Connecticut ("Optics"), APPLIED PHOTONIC
         DEVICES. INC., a Delaware corporation with a principal place of
         business at 50 Tiffany Street, Brooklyn, Connecticut
         ("Photonic-Delaware") and SPECTRAN COMMUNICATION FIBER TECHNOLOGIES,
         INC., a Delaware corporation with a principal place of business at 50
         Hall Road, Sturbridge, Massachusetts ("Communication"). Each of
         SpecTran, Optics, Photonic-Delaware and Communication are sometimes
         referred to as a "Borrower" and collectively the "Borrowers".

                  WHEREAS, the Lender, SpecTran, Optics, Communication and
         Applied Photonic Devices, Inc., a Connecticut corporation with a
         principal place of business 50 Tiffany Street, Brooklyn, Connecticut
         ("Photonic") are parties to that certain Loan and Security Agreement
         dated April 25, 1996 (the "Agreement"); and

                  WHEREAS, Photonic has been merged into Photonic-Delaware; and

                  WHEREAS, Photonic-Delaware should be a party to the Agreement;
         and

                  WHEREAS, the Lender and the Borrowers desire to amend the
         Agreement.

                  NOW, THEREFORE, in consideration of the mutual covenants
         contained herein and other good and valuable consideration, the receipt
         and sufficiency of which is hereby acknowledged, the Lender and the
         Borrowers hereby amend the Agreement as set forth hereinafter:

         A.       AMENDMENTS TO AGREEMENT

                  1.  The Agreement is amended in its entirety by replacing
         Photonic with Photonic-Delaware as a party thereto. All 
         representations, warranties, covenants and agreements of Photonic 
         contained in the Agreement are, by operation of law and hereby, 
         assumed by Photonic-Delaware. References to the Borrowers in the 
         Agreement shall mean and include any one or more of SpecTran, Optics, 
         Photonic-Delaware and Communication. All Obligations including all 
         obligations to pay all amounts owed to the Lender pursuant to any and 
         all documents evidencing the Loans, including without limitation the 
         Agreement and the Notes are the joint and several obligations of each 
         of SpecTran, Optics, Photonic-Delaware and Communication. In 
         accordance with Article 4 of the Agreement, Photonic-Delaware, as 
         security for the prompt satisfaction of all of the Obligations, hereby
         assigns to the Lender, all of its right, title and interest in and to,
         and grants the Lender a lien upon and a continuing security interest 
         in, all of its assets, including without limitation, the Collateral 
         wherever located, whether now owned or hereafter acquired, together 
         with all replacements therefor and proceeds thereof (including, but 
         without limitation, insurance proceeds) and products thereof all as 
         more fully set forth in Article 4 of the Agreement.

                  2.  Restate the initial paragraph of the Agreement as follows:

                  THIS LOAN AND SECURITY AGREEMENT is dated as of April 25, 1996
                  and is among SPECTRAN CORPORATION ("SpecTran"), SPECTRAN
                  SPECIALTY OPTICS 


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                                                                   EXHIBIT 10.77


                  COMPANY ("Optics"), APPLIED PHOTONIC DEVICES, INC.
                  ("Photonic-Delaware"), SPECTRAN COMMUNICATION FIBER
                  TECHNOLOGIES, INC. ("Communication") and FLEET NATIONAL BANK
                  (the "Lender"). Each of SpecTran, Optics, Photonic-Delaware 
                  and Communication are sometimes referred to as a "Borrower" 
                  and collectively the "Borrowers".

                  3.  Restate the paragraph under the heading "BACKGROUND" on
         Page 1 of the Agreement as follows:

                  BACKGROUND. The Borrowers have requested the Lender to lend up
                  to the sum of (i) $14,500,000.00 on a revolving loan basis,
                  (ii) $4,000,000.00 on a term loan basis, and (iii)
                  $3,500,000.00 on a mortgage loan basis (collectively the
                  "Loans") and the Lender is willing to do so upon the terms and
                  conditions hereinafter set forth.

                  4.  Restate Section 1.05(a) of the Agreement as follows:

                  (a) $14,500,000.00; or

                  5.  Restate Section 2.01 the Agreement as follows:

                  2.01 General Terms.

                  Subject to the terms hereof, the Lender will lend the
                  Borrowers the principal sum of (i) $14,500,000.00 on a
                  revolving loan basis, (ii) $4,000,000.00 on a term loan basis,
                  and (iii) $3,500,000.00 on a mortgage loan basis.

                  6.  Restate Section 2.05 of the Agreement as follows:

                  2.05 Term Note.

                      Subject to the terms hereof, the Lender agrees to lend to

                  the Borrowers on a term loan basis the amount of
                  $4,000,000.00, the payment terms to be in accordance with the
                  provisions of the Term Note. Advances under the Term Note will
                  only be made in accordance with and subject to the conditions
                  contained in EXHIBIT 2.05 attached hereto. The outstanding
                  principal balance of the Term Note is to be paid in equal
                  quarterly installments of $200,000.00. The Term Note is to be
                  due and payable in any event on April1, 2001. In addition, the
                  Borrowers will be required to prepay the Term Note to the
                  extent of the Borrowers' "Excess Cash Flow" as defined in the
                  Term Note. The outstanding principal balance of the Term Note
                  shall at no time exceed eighty and nine-tenths percent (80.9%)
                  of the orderly liquidation value of the Borrowers' Equipment,
                  and if, at any time, an excess for any reason shall exist, the
                  full amount of such excess, together with accrued and unpaid
                  interest thereon, shall be immediately due and payable in
                  full.

                  7.  Amend Section 2.06 of the Agreement by deleting from the 
         second line "$5,000.000.00" and inserting "$3,500,000.00".

                  8.  Amend Exhibit 2.05 of the Agreement by deleting from the
         eleventh line "seventy-five percent (75%) of the auction value" and
         inserting "eighty and nine-tenths percent (80.9%) of the orderly
         liquidation value".

                  9.  Amend Exhibit 2.06 of the Agreement be deleting from the
         sixteenth line "seventy- five percent (75%)" and inserting "eighty
         percent (80%)".


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                  10. Amend Exhibit 5.01 (a) to the Agreement by deleting 
         paragraph 2 and inserting the following:

                  2.  The following companies are qualified to do business in 
         the following states:

                            Name             State
                            ----             -----

                      SpecTran               Delaware, Massachusetts

                      Optics                 Delaware, Connecticut

                      Photonic-Delaware      Delaware, Connecticut

                      Communication          Delaware, Massachusetts

         B.       MISCELLANEOUS

                  1.  All capitalized terms used herein and not defined herein
         shall have the meanings ascribed in the Agreement.

                  2.  The Borrowers hereby represent and warrant to the Lender
         that no default or Event of Default exists under the Agreement and they
         have performed all of their obligations to be performed to date under
         the Agreement.

                  3.  This First Amendment shall not extinguish, terminate or
         impair any of the obligations of the Borrowers under the Agreement or
         any of the financing instruments. In addition, this First Amendment
         shall not release or impair the priority of any security interests or
         liens held by the Lender on any assets of the Borrowers.

                  4.  Except as herein expressly amended, the Agreement and the
         financing instruments shall remain unchanged and are in full force and
         effect, and the Borrowers, by executing this First Amendment, hereby
         ratify and reaffirm each covenant, representation, warranty and
         agreement contained in the Agreement and the financing instruments.

                  WITNESS the execution hereof as an instrument under seal as of
         this 4th day of September, 1996.

                                   SPECTRAN CORPORATION

                                   By: /s/ Bruce A. Cannon
                                       ----------------------------------
                                       Its Duly Authorized Officer

                                   SPECTRAN SPECIALTY OPTICS COMPANY

                                   By: /s/ Bruce A. Cannon
                                       ----------------------------------
                                       Its Duly Authorized Officer

                                   APPLIED PHOTONIC DEVICES, INC.

                                   By: /s/ Bruce A. Cannon
                                       ----------------------------------
                                       Its Duly Authorized Officer

                                   SPECTRAN COMMUNICATION FIBER
                                   TECHNOLOGIES, INC.


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                                                                   EXHIBIT 10.77


                                   By: /s/ Bruce A. Cannon
                                       ----------------------------------
                                       Its Duly Authorized Officer

                                   FLEET NATIONAL BANK

                                   By: /s/ John F. Lynch, VP
                                       ----------------------------------
                                       Its Duly Authorized Officer



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