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                                 EXHIBIT 10.96


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                                   SCHEDULE 3
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                 SPECTRAN COMMUNICATION FIBER TECHNOLOGIES, INC.
                        SPECTRAN SPECIALTY OPTICS COMPANY
                         APPLIED PHOTONIC DEVICES, INC.




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                               GUARANTY AGREEMENT
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                          DATED AS OF DECEMBER 1, 1996


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                                                 TABLE OF CONTENTS                                             PAGE


                                                                                                           
1.       PRELIMINARY STATEMENTS.................................................................................  1

2.       GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS.............................................................  2
         2.1      Guarantied Obligations........................................................................  2
         2.2      Payments and Performance......................................................................  2
         2.3      Waivers and Other Agreements..................................................................  3
         2.4      Nature of Guaranty............................................................................  4
         2.5      Obligations Absolute..........................................................................  4
         2.6      No Investigation by Noteholder................................................................  5
         2.7      Indemnity.....................................................................................  5
         2.8      Subordination, Subrogation, Etc...............................................................  5
         2.9      Waiver........................................................................................  6
         2.10     Limitation on Guarantied Obligations..........................................................  6
         2.11     Marshaling....................................................................................  6
         2.12     Setoff, Counterclaim or Other Deductions......................................................  6
         2.13     No Election of Remedies by Noteholders........................................................  6
         2.14     Separate Action; Other Enforcement Rights.....................................................  7
         2.15     Noteholder Setoff.............................................................................  7
         2.16     Delay or Omission; No Waiver..................................................................  7
         2.17     Restoration of Rights and Remedies............................................................  7
         2.18     Cumulative Remedies...........................................................................  7

3.       INTERPRETATION OF THIS GUARANTY AGREEMENT..............................................................  8
         3.1      Terms Defined.................................................................................  8
         3.2      Headings; Independent Construction............................................................  9
         3.3      Separate Agreements...........................................................................  9
         3.4      Partial Invalidity............................................................................  9
         3.5      Governing Law................................................................................. 10

4.       WARRANTIES AND REPRESENTATIONS......................................................................... 10

5.       GENERAL COVENANTS...................................................................................... 10
         5.1      Undertakings in Note Purchase Agreement....................................................... 10
         5.2      Further Assurances............................................................................ 10

6.       MISCELLANEOUS.......................................................................................... 10
         6.1      Communications................................................................................ 10
         6.2      Amendment..................................................................................... 11
         6.3      Successors and Assigns........................................................................ 11
         6.4      Survival...................................................................................... 11
         6.5      Joinder Agreement............................................................................. 11
         6.6      Expense....................................................................................... 12
         6.7      Benefits of Guaranty Restricted to Noteholders................................................ 12
         6.8      Entire Agreement.............................................................................. 12
         6.9      Connecticut Waiver............................................................................ 13
         6.10     Counterparts.................................................................................. 13


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                               GUARANTY AGREEMENT

         GUARANTY AGREEMENT (as may be amended, restated or otherwise modified
from time to time, this "AGREEMENT"), dated as of December 1, 1996, by SPECTRAN
COMMUNICATION FIBER TECHNOLOGIES, INC. ("SCFT"), a Delaware corporation,
SPECTRAN SPECIALTY OPTICS COMPANY ("SSOC"), a Delaware corporation, and APPLIED
PHOTONIC DEVICES, INC. ("APD"), a Delaware corporation (SCFT, SSOC and APD,
together with each other Person that becomes a party hereto from time to time by
execution and delivery of a Joinder Agreement, and including their respective
successors and assigns, the "GUARANTORS"), in favor of each of the Noteholders
(as such term is hereinafter defined).

1.       PRELIMINARY STATEMENTS

         1.1 Spectran Corporation (together with its successors and assigns, the
"COMPANY"), a Delaware corporation, has authorized the issuance of

                  (a) its 9.24% Series A Senior Secured Notes due 2003 (as may
         be amended, restated or otherwise modified from time to time, the
         "SERIES A NOTES"), in the aggregate principal amount of $16,000,000,
         and

                  (b) its 9.39% Series B Senior Secured Notes due 2004 (as may
         be amended, restated or otherwise modified from time to time, the
         "SERIES B NOTES," and collectively with the Series A Notes and any and
         all other notes for which such notes, or any successor notes, may be
         substituted or exchanged, all as may be amended, restated or otherwise
         modified from time to time, the "NOTES"), in the aggregate principal
         amount of $8,000,000,

pursuant to the separate Note Purchase Agreements (collectively, as may be
amended, restated or otherwise modified from time to time, the "NOTE PURCHASE
AGREEMENT"), each dated as of December 1, 1996, with each of the purchasers
named on Schedule A thereto (the "PURCHASERS").

         1.2 In order to induce the Purchasers to purchase the Notes, each of
SCFT, SSOC and APD has agreed to become a Guarantor hereunder and the Company
has agreed, pursuant to the Note Purchase Agreement, that each other Person that
at any time becomes a direct or indirect Subsidiary will be required to become a
Guarantor hereunder.

         1.3 The Guarantors and the Company are operated as part of one
consolidated business entity. The Guarantors are directly dependent upon the
Company for and in connection with their respective business activities and
their respective financial resources. Each Guarantor will receive direct and
indirect economic and financial benefits from the indebtedness incurred under
the Note Purchase Agreement and the Notes by the Company, and under this
Agreement, and the incurrence of such indebtedness is in the best interests of
such Guarantor.

         1.4 All acts and proceedings required by law and by the constitutive
documents of each Guarantor necessary to constitute this Agreement a valid and
binding agreement for the uses and purposes set forth herein, in accordance with
its terms, have been done and taken, and the execution and delivery hereof has
been in all respects duly authorized.

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                                   2. GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS



2.       GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS

         2.1 GUARANTIED OBLIGATIONS.

         Each Guarantor, in consideration of the execution and delivery of the
Note Purchase Agreement, the purchase of the Notes by the Purchasers and other
consideration, hereby irrevocably, unconditionally, absolutely, jointly and
severally guarantees to each Noteholder, as and for each such Guarantor's own
debt:

                  (a) the due and punctual payment of the principal of and
         accrued and unpaid interest (including, without limitation, interest
         which otherwise may cease to accrue by operation of any insolvency law,
         rule, regulation or interpretation thereof) and Make-Whole Amount on
         the Notes and the due and punctual payment of all other obligations of
         the Company to the Noteholders under the Note Purchase Agreement, the
         Notes and the other Financing Documents when due, whether by mandatory
         or optional prepayment, acceleration or otherwise, all in accordance
         with the terms thereof, including, without limitation, overdue
         interest, indemnification payments and all reasonable costs and
         expenses incurred by the Noteholders and the Trustee in connection with
         enforcing any obligations of the Company under the Note Purchase
         Agreement, the Notes and the other Financing Documents, including,
         without limitation, the reasonable fees and disbursements of
         Noteholders' special counsel;

                  (b) the punctual and faithful performance, keeping,
         observance, and fulfillment by the Company of all duties, agreements,
         covenants and obligations of the Company contained in the Note Purchase
         Agreement, the Notes and the other Financing Documents to be performed
         or observed on the part of the Company; and

                  (c) the prompt and complete payment, on demand, of any and all
         reasonable costs and expenses incurred by the Noteholders in connection
         with enforcing the obligations of such Guarantor hereunder, including,
         without limitation, the reasonable fees and disbursements of the
         Noteholders' special counsel.

All of the obligations set forth in clauses (a), (b) and (c) of this Section 2.1
are referred to herein as the "GUARANTIED OBLIGATIONS" and the guaranty thereof
contained herein is a primary, original and immediate obligation of each
Guarantor and is an absolute, unconditional, continuing and irrevocable guaranty
of payment and performance and shall remain in full force and effect until the
full, final and indefeasible payment of the Guarantied Obligations.

         2.2 PAYMENTS AND PERFORMANCE.

         If for any reason any duty, agreement or obligation of the Company
contained in the Note Purchase Agreement or any other Financing Document shall
not be performed or observed by the Company as provided therein, or if any
amount payable under or in connection with the Note Purchase Agreement, the
Notes or any other Financing Document shall not be paid in full when the same
becomes due and payable, each Guarantor undertakes to perform or cause to be
performed promptly each of such duties, agreements and obligations and to pay
forthwith each

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such amount to the Noteholders regardless of any defense or setoff or
counterclaim which the Company may have or assert, and regardless of any other
condition or contingency.

         2.3 WAIVERS AND OTHER AGREEMENTS.

         Each Guarantor hereby unconditionally:

                  (a) waives any requirement that the Noteholders, upon the
         occurrence of an Event of Default, first make demand upon, or seek to
         enforce remedies against, the Company before demanding payment under or
         seeking to enforce the obligations of such Guarantor under this
         Agreement;

                  (b) agrees that the obligations of such Guarantor under this
         Agreement will not be discharged except by complete performance of all
         obligations of the Company contained in the Note Purchase Agreement,
         the Notes and the other Financing Documents;

                  (c) agrees that the obligations of such Guarantor under this
         Agreement shall remain in full force and effect without regard to, and
         shall not be affected or impaired, without limitation, by any
         invalidity, irregularity or unenforceability in whole or in part of the
         Note Purchase Agreement, the Notes or any other Financing Document, or
         any limitation on the liability of any Guarantor under this Agreement,
         or any limitation on the method or terms of payment under the Note
         Purchase Agreement, the Notes or any other Financing Document which may
         at any time be caused or imposed in any manner whatsoever (including,
         without limitation, usury laws);

                  (d) waives diligence, presentment and protest with respect to,
         and any notice of default or dishonor in the payment of any amount at
         any time payable by the Company under or in connection with the Note
         Purchase Agreement, the Notes or any other Financing Document, and
         further waives any requirement of notice of acceptance of, or other
         formality relating to, the obligations of such Guarantor under this
         Agreement; and

                  (e) agrees that to the extent the Company makes a payment or
         payments to any Noteholder, which payment or payments or any part
         thereof are subsequently invalidated, declared to be fraudulent or
         preferential, set aside or required, for any of the foregoing reasons
         or for any other reason, to be repaid or paid over to a custodian,
         trustee, receiver or any other party or officer under any bankruptcy,
         reorganization, arrangement, insolvency, readjustment of debt,
         dissolution or liquidation law of any jurisdiction, state or federal
         law, or any common law or equitable cause, then to the extent of such
         payment or repayment, the obligation or part thereof intended to be
         satisfied shall be revived and continued in full force and effect as if
         said payment had not been made and each Guarantor shall be primarily
         liable for such obligation.


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                                   2. GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS


         2.4 NATURE OF GUARANTY.

         The obligations of each Guarantor under this Agreement constitute an
absolute and unconditional and irrevocable guaranty of payment and not a
guaranty of collection and are wholly independent of and in addition to other
rights and remedies of the Noteholders and are not contingent upon the pursuit
by the Noteholders of any such rights and remedies, such pursuit being hereby
waived by such Guarantor. Notwithstanding anything to the contrary set forth in
the Note Purchase Agreement, the Notes or any other Financing Document, the
obligations of each Guarantor under this Agreement are joint and several with
the obligations of each other Guarantor and any other guarantor of all or any
part of the Guarantied Obligations.

         2.5 OBLIGATIONS ABSOLUTE.

         The obligations, covenants, agreements and duties of each Guarantor
under this Agreement shall not be released, affected or impaired by any of the
following, whether or not undertaken with notice to or consent of such
Guarantor:

                  (a) any assignment or transfer, in whole or in part, of any
         Note although made without notice to or consent of such Guarantor; or

                  (b) any waiver by any Noteholder, or by any other Person, of
         the performance or observance by the Company of any of the agreements,
         covenants, terms or conditions contained in the Note Purchase Agreement
         or in any other Financing Document; or

                  (c) any indulgence in or the extension of the time for payment
         by the Company of any amounts payable under or in connection with the
         Note Purchase Agreement, the Notes or any other Financing Document, or
         of the time for performance by the Company of any other obligations
         under or arising out of the Note Purchase Agreement, the Notes or any
         other Financing Document, or the extension or renewal thereof; or

                  (d) the modification, amendment or waiver (whether material or
         otherwise) of any duty, agreement or obligation of the Company set
         forth in the Note Purchase Agreement, the Notes or any other Financing
         Document (the modification, amendment or waiver from time to time of
         the Note Purchase Agreement, the Notes and the other Financing
         Documents being expressly authorized without further notice to or
         consent of such Guarantor); or

                  (e) the voluntary or involuntary liquidation, sale or other
         disposition of all or substantially all of the assets of the Company or
         any receivership, insolvency, bankruptcy, reorganization or other
         similar proceedings affecting the Company or any of its assets; or

                  (f) the merger or consolidation of the Company or any
         Guarantor with any other Person; or

                  (g) the release or discharge of the Company from the
         performance or observance of any agreement, covenant, term or condition
         contained in the Note

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         Purchase Agreement, the Notes or any other Financing Document, by
         operation of law; or

                  (h) any other cause, whether similar or dissimilar to the
         foregoing, that would release, affect or impair the obligations,
         covenants, agreements or duties of any Guarantor under this Agreement.

         2.6 NO INVESTIGATION BY NOTEHOLDER.

         Each Guarantor hereby waives unconditionally any obligation that, in
the absence of such provision, the Noteholders might otherwise have to
investigate or to assure that there has been compliance with the law of any
jurisdiction with respect to the Guarantied Obligations, recognizing that, to
save both time and expense, such Guarantor has requested that the Noteholders
not undertake such investigation. Each Guarantor hereby expressly confirms that
the obligations of such Guarantor hereunder shall remain in full force and
effect without regard to compliance or noncompliance with any such law and
irrespective of any investigation or knowledge of any such law by any
Noteholder.

         2.7      INDEMNITY.

         As a separate, additional and continuing obligation, each Guarantor
unconditionally and irrevocably undertakes and agrees with the Noteholders that,
should the Guarantied Obligations not be recoverable from such Guarantor for any
reason whatsoever (including, without limitation, by reason of any provision of
the Note Purchase Agreement, the Notes, any other Financing Document or any
other agreement or instrument executed in connection therewith being or becoming
void, unenforceable or otherwise invalid under any applicable law) then,
notwithstanding any knowledge thereof by any Noteholder at any time, such
Guarantor as sole, original and independent obligor, upon demand by the Required
Holders, will make payment of the Guarantied Obligations to the Noteholders by
way of a full indemnity in such currency and otherwise in such manner as is
provided in the Note Purchase Agreement and the Notes.

         2.8      SUBORDINATION, SUBROGATION, ETC.

         Each Guarantor agrees that any present or future indebtedness,
obligations or liabilities of the Company to such Guarantor shall be fully
subordinate and junior in right and priority of payment to any present or future
indebtedness, obligations or liabilities of the Company to the Noteholders. Each
Guarantor waives any right of subrogation to the rights of the Noteholders
against the Company or any other Person obligated for payment of the Guarantied
Obligations and any right of reimbursement, contribution or indemnity whatsoever
(including, without limitation, any such right as against any other Guarantor)
arising or accruing out of any payment that such Guarantor may make pursuant to
this Agreement, and any right of recourse to security for the debts and
obligations of the Company, unless and until the entire amount of the Guarantied
Obligations shall have been paid in full.


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                                   2. GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS


         2.9      WAIVER.

         To the extent that it lawfully may, each Guarantor agrees that it will
not at any time insist upon or plead, or in any manner whatsoever claim or take
any benefit or advantage of, any applicable present or future stay, extension or
moratorium law, which may affect observance or performance of the provisions of
this Agreement, the Note Purchase Agreement, the Notes or any other Financing
Document; nor will it claim, take or insist upon any benefit or advantage of any
present or future law providing for the evaluation or appraisal of any security
for its obligations hereunder or the Company under the Note Purchase Agreement,
the Notes or any other Financing Document prior to any sale or sales thereof
which may be made under or by virtue of any instrument governing the same; nor
will it, after any such sale or sales, claim or exercise any right, under any
applicable law, to redeem any portion of such security so sold.

         2.10     LIMITATION ON GUARANTIED OBLIGATIONS.

         Notwithstanding anything in Section or elsewhere in this Agreement, the
Note Purchase Agreement, the Notes or any other Financing Document to the
contrary, the obligations of each Guarantor under this Agreement shall at each
point in time be limited to an aggregate amount equal to the greatest amount
that would not result in such obligations being subject to avoidance, or
otherwise result in such obligations being unenforceable, at such time under
applicable law (including, without limitation, to the extent, and only to the
extent, applicable to any such Guarantor, Section 548 of the Bankruptcy Code of
the United States of America and any comparable provisions of the law of any
other jurisdiction, any capital preservation law of any jurisdiction and any
other law of any jurisdiction that at such time limits the enforceability of the
obligations of such Guarantor under this Agreement).

         2.11     MARSHALING.

         Neither any Noteholder nor any Person acting for the benefit of any
Noteholder shall be under any obligation to marshal any assets in favor of any
Guarantor or against or in payment of any or all of the Guarantied Obligations.

         2.12     SETOFF, COUNTERCLAIM OR OTHER DEDUCTIONS.

         Except as otherwise required by law, each payment by each Guarantor
shall be made without setoff, counterclaim or other deduction.

         2.13     NO ELECTION OF REMEDIES BY NOTEHOLDERS.

         No election to proceed in one form of action or proceeding, or against
any party, or on any obligation, shall constitute a waiver of such Noteholder's
right to proceed in any other form of action or proceeding or against other
parties unless such Noteholder has expressly waived such right in writing.
Specifically, but without limiting the generality of the foregoing, no action or
proceeding by any Noteholder against the Company or any Guarantor under any
document or instrument evidencing obligations of the Company or any Guarantor to
such Noteholder shall serve to diminish the liability of any Guarantor under
this Agreement, except to the extent that

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                                   2. GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS

such Noteholder finally and unconditionally shall have realized payment by such
action or proceeding in respect of the Guarantied Obligations.

         2.14 SEPARATE ACTION; OTHER ENFORCEMENT RIGHTS.

         Each of the rights and remedies granted under this Agreement to each
Noteholder in respect of the Notes held by such Noteholder may be exercised by
such Noteholder without notice by such Noteholder to, or the consent of or any
other action by, any other Noteholder. Each Noteholder may proceed to protect
and enforce this Agreement by suit or suits or proceedings in equity, at law or
in bankruptcy, and whether for the specific performance of any covenant or
agreement contained herein or in execution or aid of any power herein granted or
for the recovery of judgment for the obligations hereby guarantied or for the
enforcement of any other proper, legal or equitable remedy available under
applicable law.

         2.15 NOTEHOLDER SETOFF.

         Each Noteholder shall have, to the fullest extent permitted by law and
this Agreement, a right of set-off against any and all credits and any and all
other property of each Guarantor now or at any time whatsoever, with or in the
possession of such Noteholder, or anyone acting for such Noteholder, to ensure
the full performance of any and all obligations of each Guarantor hereunder.

         2.16 DELAY OR OMISSION; NO WAIVER.

         No course of dealing on the part of any Noteholder and no delay or
failure on the part of any such Person to exercise any right hereunder shall
impair such right or operate as a waiver of such right or otherwise prejudice
such Person's rights, powers and remedies hereunder. Every right and remedy
given by this Agreement or by law to any Noteholder may be exercised from time
to time as often as may be deemed expedient by such Person.

         2.17 RESTORATION OF RIGHTS AND REMEDIES.

         If any Noteholder shall have instituted any proceeding to enforce any
right or remedy under this Agreement or under any Note held by such Noteholder,
and such proceeding shall have been dismissed, discontinued or abandoned for any
reason, or shall have been determined adversely to such Noteholder, then and in
every such case each such Noteholder, the Company and each Guarantor shall,
except as may be limited or affected by any determination (including, without
limitation, any determination in connection with any such dismissal) in such
proceeding, be restored severally and respectively to its respective former
positions hereunder and thereunder, and thereafter, subject as aforesaid, the
rights and remedies of such Noteholders shall continue as though no such
proceeding had been instituted.

         2.18 CUMULATIVE REMEDIES.

         No remedy under this Agreement, the Note Purchase Agreement, the Notes
or any other Financing Document is intended to be exclusive of any other remedy,
but each and every remedy

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                                   2. GUARANTY AND OTHER RIGHTS AND UNDERTAKINGS


shall be cumulative and in addition to any and every other remedy given pursuant
to this Agreement, the Note Purchase Agreement, the Notes or any other Financing
Document.

3.       INTERPRETATION OF THIS GUARANTY AGREEMENT

         3.1 TERMS DEFINED.

         For purposes of this Agreement, the following terms have the meanings
specified below or provided for in the section of this Agreement referred to
immediately following such term (such definitions to be equally applicable to
both the singular and plural forms of the terms defined) or, if not defined
herein, then as defined in the Trust Indenture.

         COMPANY -- Section 1.1.

         DEFAULT -- has the meaning assigned to such term in the Note Purchase
Agreement.

         EVENT OF DEFAULT -- has the meaning assigned to such term in the Note
Purchase Agreement.

         GUARANTIED OBLIGATIONS -- Section 2.1.

         GUARANTORS -- has the meaning assigned to such term in the introductory
paragraph hereof.

         JOINDER AGREEMENT -- Section 6.5.

         LIEN -- has the meaning assigned to such term in the Note Purchase
Agreement.

         NOTE PURCHASE AGREEMENT -- Section 1.1(b).

         NOTEHOLDER -- means, at any time, each Person that is the holder of any
Note at such time.

         NOTES -- has the meaning assigned to such term in Preliminary Statement
A.

         PERSON -- means an individual, partnership, corporation, limited
liability company, association, trust, unincorporated organization, or a
government or agency or political subdivision thereof.

         PURCHASERS -- Section 1.1(b).

         PROPERTY -- means, unless otherwise specifically limited, real or
personal property of any kind, tangible or intangible, choate or inchoate.

         REQUIRED HOLDERS -- has the meaning assigned to such term in the Note
Purchase Agreement.


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                                    3. INTERPRETATION OF THIS GUARANTY AGREEMENT


         SERIES A NOTES -- Section 1.1(a), 1.1(a), 1.1(b).

         SERIES B NOTES -- Section 1.1(b).

         SUBSIDIARY -- has the meaning assigned to such term in the Note
Purchase Agreement.

         TRUSTEE -- has the meaning assigned to such term in the Trust
Indenture, dated as of December 1, 1996, among the Company, the Guarantors,
Fleet National Bank as trustee, and the other parties signatory thereto, as
amended, modified or supplemented from time to time.

         3.2 HEADINGS; INDEPENDENT CONSTRUCTION.

                  (a) SECTION HEADINGS ETC. The titles of the Sections and Table
         of Contents of this Agreement appear as a matter of convenience only,
         do not constitute a part hereof and shall not affect the construction
         hereof. The words "herein," "hereof," "hereunder" and "hereto" refer to
         this Indenture as a whole and not to any particular Section or other
         subdivision. References to Sections are, unless otherwise specified,
         references to Sections of this Agreement. References to Annexes,
         Schedules, Exhibits and Attachments are, unless otherwise specified,
         references to Annexes, Schedules, Exhibits and Attachments attached to
         this Agreement.

                  (b) CONSTRUCTION. Each covenant contained herein shall be
         construed (absent an express contrary provision herein) as being
         independent of each other covenant contained herein, and compliance
         with any one covenant shall not (absent such an express contrary
         provision) be deemed to excuse compliance with one or more other
         covenants.

         3.3 SEPARATE AGREEMENTS.

         Notwithstanding that this Agreement is among each of the Guarantors and
the Trustee, this Agreement shall be construed and interpreted as a separate
Agreement between each Guarantor and the Trustee, and any whole or partial
invalidity of this Agreement in respect of any Guarantor shall not have any
effect on the validity or enforceability of this Agreement as among each other
Guarantor, respectively, as the case may be, and the Trustee.

         3.4 PARTIAL INVALIDITY.

         The unenforceability or invalidity of any provision or provisions of
this Agreement shall not render any other provision or provisions contained in
this Agreement unenforceable or invalid.

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         3.5 GOVERNING LAW.

         THIS AGREEMENT SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY
THE LAW OF THE COMMONWEALTH OF MASSACHUSETTS EXCLUDING CHOICE-OF-LAW PRINCIPLES
OF THE LAW OF SUCH JURISDICTION THAT WOULD REQUIRE THE APPLICATION OF THE LAWS
OF A JURISDICTION OTHER THAN SUCH JURISDICTION.

4.       WARRANTIES AND REPRESENTATIONS

         Each Guarantor warrants and represents, as of the date such Guarantor
becomes a Guarantor hereunder, that each of the warranties and representations
made by the Company in Section 5 of the Note Purchase Agreement with respect to
Subsidiaries generally are true with respect to such Guarantor on the date that
such Guarantor becomes a Guarantor, with the same effect as though such
warranties and representations were made on and as of such date rather than on
and as of the date of this Agreement.

5.       GENERAL COVENANTS

         Each Guarantor covenants and agrees that on and after the date hereof
and so long as any of the Guarantied Obligations shall be outstanding:

         5.1 UNDERTAKINGS IN NOTE PURCHASE AGREEMENT.

         Each Guarantor will comply with each of the undertakings of the Company
in the Note Purchase Agreement in respect of which the Company undertakes to
cause such Guarantor (in its capacity as a Guarantor and as a Subsidiary) to
comply with such undertakings, as if such undertakings (as they apply to such
Guarantor) were set forth at length herein as the undertakings of such
Guarantor.

         5.2 FURTHER ASSURANCES.

         Each Guarantor will cooperate with the Noteholders and execute such
further instruments and documents as the Required Holders shall reasonably
request to carry out, to the reasonable satisfaction of the Required Holders,
the transactions contemplated by this Agreement and the other Financing
Documents.

6.       MISCELLANEOUS

         6.1 COMMUNICATIONS.

         All communications hereunder shall be in writing, shall be delivered in
the manner required by the Note Purchase Agreement, and shall be addressed, if
to any Guarantor, at the applicable address set forth on Annex 1 hereto, and if
to any of the Noteholders:


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                                                                 6 MISCELLANEOUS


                  (a) if such Noteholder is a Purchaser, at the address for such
         Noteholder set forth on Schedule A to the Note Purchase Agreement, and
         further including any parties referred to on such Schedule A which are
         required to receive notices in addition to such Noteholder, and

                  (b) if such Noteholder is not a Purchaser, at the address for
         such Noteholder set forth in the register for the registration and
         transfer of Notes maintained pursuant to Section 13.1 of the Note
         Purchase Agreement,

or to any such party at such other address as such party may designate by notice
duly given in accordance with this Section 6.1. Notices shall be deemed given
only when actually received.

         6.2 AMENDMENT.

         This Agreement may be amended in, and the observance of any term hereof
may be waived (either retroactively or prospectively), with (and only with) the
written consent of each Guarantor and the Required Holders, except that no
amendment or waiver of any of the provisions of Section 2, or any defined term
as it is used therein, will be effective unless consented to by each Guarantor
and each Noteholder in writing; provided that this Agreement may, in the manner
specified in Section 6.5, be amended to add one or more new Guarantors hereunder
without the consent of any other Guarantor or any holder of Notes.

         6.3 SUCCESSORS AND ASSIGNS.

                  (a) All covenants and other agreements contained in this
         Agreement by or on behalf of any of the parties hereto shall bind and
         inure to the benefit of their respective successors and assigns
         (including, without limitation, any subsequent holder of a Note)
         whether so expressed or not.

                  (b) Each Guarantor agrees to take such action as may be
         reasonably requested by any Noteholder to confirm such Guarantor's
         guaranty of the Guarantied Obligations in connection with the transfer
         of the Notes of such Noteholder.

         6.4 SURVIVAL.

         All representations and warranties contained herein or made in writing
by any Guarantor in connection herewith shall survive the execution and delivery
of this Agreement. So long as the Guarantied Obligations and all payment
obligations of each Guarantor hereunder shall not have been fully and finally
performed and indefeasibly paid, the obligations of each Guarantor hereunder
shall survive the transfer and payment of any Note and the payment in full of
all the Notes.

         6.5 JOINDER AGREEMENT.

         Upon execution and delivery by any Person of a counterpart of a Joinder
Agreement substantially in the form attached to this Agreement as Annex 2 (each,
a "JOINDER AGREEMENT"), this Agreement shall for all purposes, without further
action, be deemed to have been amended

                                       11
   15
                                                                 6 MISCELLANEOUS


to add such Person as a Guarantor hereunder with the same effect as if such
Person had been an original party hereto.

         6.6 EXPENSE.

                  (a) AMENDMENTS AND WAIVERS. The Guarantors will pay when
         billed the reasonable costs and expenses (including reasonable
         attorneys' fees) incurred by the Noteholders in connection with the
         consideration, negotiation, preparation or execution of any amendments,
         waivers, consents, standstill agreements and other similar agreements
         with respect hereto (whether or not any such amendments, waivers,
         consents, standstill agreements or other similar agreements are
         executed or become effective).

                  (b) RESTRUCTURING AND WORKOUT, INSPECTIONS. At any time when
         the Guarantors and the Noteholders are conducting restructuring or
         workout negotiations in respect hereof, or a Default or Event of
         Default exists, the Guarantors will pay when billed the reasonable
         costs and expenses (including reasonable attorneys' fees and the fees
         of professional advisors) incurred by the Noteholders in connection
         with the assessment, analysis or enforcement of any rights or remedies
         that are or may be available to the Noteholders and in connection with
         inspections made pursuant to Section 7.3 of the Note Purchase
         Agreement.

                  (c) COLLECTION AND ENFORCEMENT. If the Guarantors shall fail
         to pay when due any of the Guarantied Obligations or shall otherwise
         fail to comply with any provision of this Agreement, the Guarantors
         will pay to each Noteholder, to the extent permitted by law, such
         amounts as shall be sufficient to cover the costs and expenses,
         including, without limitation, reasonable attorneys' fees, incurred by
         such Noteholder in collecting any sums due hereunder and in enforcing
         any rights or remedies that are or may be available to such Noteholder.

         6.7 BENEFITS OF GUARANTY RESTRICTED TO NOTEHOLDERS.

         Nothing express or implied in this Agreement is intended or shall be
construed to give to any Person other than the Guarantors and the Noteholders
any legal or equitable right, remedy or claim under or in respect hereof or any
covenant, condition or provision therein or herein contained, and all such
covenants, conditions and provisions are and shall be held to be for the sole
and exclusive benefit of the Guarantors and the Noteholders.

         6.8 ENTIRE AGREEMENT.

         This Agreement constitutes the final written expression of all of the
terms hereof and is a complete and exclusive statement of those terms.


                                       12
   16
                                                                6. MISCELLANEOUS


         6.9 CONNECTICUT WAIVER.

         TO THE EXTENT ANY ASSETS AND/OR REAL ESTATE OF ANY GUARANTOR IS LOCATED
IN CONNECTICUT, EACH GUARANTOR ACKNOWLEDGES THAT THIS AGREEMENT AND EACH
TRANSACTION RELATED HERETO IS A "COMMERCIAL TRANSACTION" WITHIN THE MEETING OF
CHAPTER 903A OF THE CONNECTICUT GENERAL STATUES, AS AMENDED. EACH GUARANTOR
HEREBY WAIVES ANY RIGHT WHICH IT MIGHT HAVE TO NOTICE IN A HEARING OR A PRIOR
COURT ORDER, UNDER SAID CHAPTER 903A OR AS OTHERWISE PROVIDED UNDER ANY
APPLICABLE FEDERAL OR STATE LAW, IN THE EVENT THE TRUSTEE OR ANY NOTEHOLDER
SEEKS ANY PREJUDGMENT REMEDY AT ANY TIME PRIOR TO FINAL JUDGMENT IN ANY
LITIGATION INSTITUTED IN CONNECTION WITH THIS AGREEMENT OR ANY OTHER FINANCING
DOCUMENT, WHETHER BY WAY OF ATTACHMENT, FOREIGN ATTACHMENT, GARNISHMENT OR
REPLEVIN.

         6.10 COUNTERPARTS.

         This Agreement may be executed and delivered in any number of
counterparts, each of such counterparts constituting an original but altogether
only one Agreement.

   [Remainder of page intentionally left blank; next page is signature page.]

                                       13
   17
         IN WITNESS WHEREOF, each Guarantor has caused this Agreement to be
executed on its behalf by one of its duly authorized officers as of the date
first set forth above.


                                             SPECTRAN COMMUNICATION FIBER
                                             TECHNOLOGIES, INC.



                                             By /s/ Bruce A. Cannon
                                                -------------------------------
                                                Name:  Bruce A. Cannon

                                                Title: Secretary

                                             SPECTRAN SPECIALTY OPTICS
                                             COMPANY



                                             By /s/ Bruce A. Cannon
                                                -------------------------------

                                                Name:  Bruce A. Cannon

                                                Title: Secretary

                                             APPLIED PHOTONIC DEVICES, INC.



                                             By  /s/ Bruce A. Cannon
                                                --------------------------------

                                                Name:  Bruce A. Cannon

                                                Title: Secretary



                              [GUARANTY AGREEMENT]
   18
                          Annex 1 to Guaranty Agreement

                             Addresses of Guarantors

SpecTran Communication Fiber Technologies, Inc.
50 Hall Road
Sturbridge, MA 01566
Attn:  Chief Executive Officer

SpecTran Specialty Optics Company
150 Fisher Drive
Avon CT 060011(*)
Attn:  President

Applied Photonic Devices, Inc.
300 Lake Road
Dayville, CT 06241(**5)
Attn:  Chief Executive Officer


* Spectran Specialty Optics Company intends to move its principal executive
offices to 55 Darling Drive, Avon, Connecticut 06001 during 1997. 

Applied Photonic Devices, Inc. intends to move its principal executive offices
to 50 Hall Road, Sturbridge, Massachusetts by the end of 1996.



- ----------
         (5)Applied Photonic Devices, Inc. intends to move its principal
executive offices to 50 Hall Road, Sturbridge, Massachusetts by the end of 1996.
   19
                                                                         ANNEX 2

                           [FORM OF JOINDER AGREEMENT]


                                JOINDER AGREEMENT

                                                                          [Date]



To each of the Noteholders (as defined in the Guaranty
         Agreement hereinafter referred to)

Ladies and Gentlemen:

         Reference is made to the Guaranty Agreement, dated as of December 1,
1996 (as amended, restated or otherwise modified from time to time, the
"GUARANTY AGREEMENT"), by SpecTran Communication Fiber Technologies, Inc.
("SCFT"), a Delaware corporation, SpecTran Specialty Optics Company ("SSOC"), a
Delaware corporation, and APPLIED PHOTONIC DEVICES, INC. ("APD"), a Delaware
corporation (SCFT, SSOC and APD, together with each other Person that becomes a
party to the Guaranty Agreement, the "GUARANTORS"), in favor of each of the
Noteholders (as defined in the Agreement). Capitalized terms used herein and not
otherwise defined have the meanings ascribed to such terms in the Guaranty
Agreement.

         [NEW GUARANTOR], a ___________________ corporation (the "NEW
GUARANTOR"), agrees with you as follows:

         1. GUARANTY. The New Guarantor hereby unconditionally and expressly
agrees to become, and by execution and delivery of this Agreement does become, a
"Guarantor" under and as defined in the Guaranty Agreement. Without limitation
of the foregoing or of anything in the Guaranty Agreement, by such execution and
delivery hereof the New Guarantor does become fully liable, as a Guarantor, for
the payment of the Guarantied Obligations as further provided in Section 1 of
the Guaranty Agreement. As provided in Section 6.5 of the Guaranty Agreement,
the Guaranty Agreement is hereby amended, without any further action, to add the
New Guarantor as a Guarantor thereunder as if the New Guarantor had been an
original party to the Guaranty Agreement. Annex 1 to the Guaranty Agreement is
hereby amended by adding the following address of the New Guarantor for purposes
of communications pursuant to Section 6.1 of the Guaranty Agreement: [insert
name and address of New Guarantor].

         2. FURTHER ASSURANCES. The New Guarantor agrees to cooperate with the
Noteholders and execute such further instruments and documents as the Required
Holders shall reasonably request to effect, to the reasonable satisfaction of
the Required Holders, the purposes of this Agreement.

         3. BINDING EFFECT. This Agreement shall be binding upon the New
Guarantor and shall inure to the benefit of the Noteholders and their respective
successors and assigns.


                                    Annex 2-1
   20
         IN WITNESS WHEREOF, the New Guarantor has caused this Agreement to be
executed on its behalf by one of its duly authorized officers.

                                        [NEW GUARANTOR]



                                        By
                                           ------------------------------------

                                                 Name:

                                                 Title:


                                    Annex 2-2