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                                                                     Exhibit 4.2

                                FIRST DEBENTURE A

NEITHER THESE SECURITIES NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE
CONVERTIBLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER RULE 504 OF REGULATION D PROMULGATED UNDER THE U.S.
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT") AND IN COMPLIANCE WITH
APPLICABLE STATE SECURITIES LAWS.

US $492,750                                                   September 22, 2003

                 1% CONVERTIBLE DEBENTURE DUE SEPTEMBER 21, 2008

     THIS DEBENTURE of Ophthalmic Solutions, Inc., a Delaware corporation (the
"Company") in the aggregate principal amount of Four Hundred Ninety Two Thousand
Seven Hundred Fifty Dollars (US $492,750), is designated as its $492,750, 1%
Convertible Debenture due September 21, 2008 (the "Debentures").

     FOR VALUE RECEIVED, the Company promises to pay to HEM Mutual Assurance LLC
or its registered assigns (the "Holder"), the principal sum of Four Hundred
Ninety Two Thousand Seven Hundred Fifty Dollars (US $492,750), on or prior to
September 21, 2008 (the "Maturity Date") and to pay interest to the Holder on
the principal sum at the rate of one percent (1%) per annum. Interest shall
accrue daily commencing on the Original Issuance Date (as defined in Section 1
below) in the form of cash or common stock of the Company selected by the Holder
subject to the provisions of Section 2(b) hereof, until payment in full of the
principal sum, together with all accrued and unpaid interest, has been made or
duly provided for. If at any time after the Original Issuance Date an Event of
Default has occurred and is continuing, interest shall accrue at the rate of
eight percent (8%) per annum from the date of the Event of Default and the
applicable cure period through and including the date of payment. Interest due
and payable hereunder shall be paid to the person in whose name this Debenture
(or one or more successor Debentures) is registered on the records of the
Company regarding registration and transfers of the Debentures (the "Debenture
Register"); provided, however, that the Company's obligation to a transferee of
this Debenture shall arise only if such transfer, sale or other disposition is
made in accordance with the terms and conditions hereof and of the Convertible
Debenture Purchase Agreement (the "Purchase Agreement") by and between the
Company and the Purchaser (as such term is defined in the Purchase Agreement),
dated as of September 22, 2003, as the same may be amended from time to time. A
transfer of the right to receive principal and interest under this Debenture
shall be transferable only through an appropriate entry in the Debenture
Register as provided herein.

     If the Company in order to consummate a merger (the "Merger") enters into a
merger agreement or similar agreement with other parties (the "Merger
Partners"), the Merger Partners will effective upon the consummation of any such
Merger assume all of the obligations, jointly and

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severally, with the Company, under this Debenture and substitute the Company's
Common Stock, into which this Debenture is convertible, for common stock of such
Merger Partner ("MP Common Stock") including depositing 5,000,000 shares of MP
Common Stock with the Escrow Agent (as defined in the Purchase Agreement). If
and when the Merger occurs, at the time such Merger is effective, the Escrow
Agent will deliver the Company's Common Stock being held in accordance with the
Purchase Agreement and this Debenture to the Company. If the Merger occurs, then
(i) references herein to Company Common Stock shall be references to MP Common
Stock and (ii) any references the Company shall be read as references to the MP
that issued the MP Common Stock as if this Debenture were issued on the date
hereof by the MP that issued the MP Common Stock and the Company shall have no
further obligations to issue shares of Common Stock hereunder. For the benefit
of the Holder, the Company shall use its best efforts to effectuate the
intentions of this paragraph.

     If there is a Merger all of the provisions of this Debenture (specifically
including Section 4) shall be read and interpreted as if this Debenture was
issued by the Merger Partner issuing the MP Common Stock on the date hereof and
this Debenture was initially convertible into MP Common Stock.

     This Debenture is subject to the following additional provisions:

     Section 1. Definitions. Capitalized terms used and not otherwise defined
herein shall have the meanings given such terms in the Purchase Agreement. As
used in this Agreement, the following terms shall have the following meanings:

     "Adjusted Conversion Price" means the lesser of the Fixed Conversion Price
or the Floating Conversion Price one day prior to the record date set for the
determination of stockholders entitled to receive dividends, distributions,
rights or warrants as provided for in Sections 4(c)(ii), (iii) and (iv).

     "Company" shall mean the Company (as defined in the Purchase Agreement) or
in the event there is a Merger, shall mean such Merger Partner that issues the
MP Common Stock.

     "Common Stock" shall mean the Common Stock (as defined in the Purchase
Agreement) and in the event there is a Merger, shall mean the MP Common Stock
(as adjusted for any reverse splits, forward splits, combination,
reclassification or stock dividend from the date the Purchase Agreement is
signed).

     "Conversion Date" shall have the meaning set forth in Section 4(a) hereof.

     "Conversion Ratio" means, at any time, a fraction, the numerator of which
is the then outstanding principal amount represented by the Debentures plus
accrued but unpaid interest thereon, and the denominator of which is the
conversion price at such time.

     "Depressed Price" shall have the meaning set forth in Section 4(c)(i)
hereof.

     "Fixed Conversion Price" shall have the meaning set forth in Section 4(c)i
hereof.

     "Floating Conversion Price" shall have the meaning set forth in Section
4(c)i hereof.

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     "Maximum Conversion" shall have the meaning set forth in Section 4(c)(i)
hereof.

     "Notice of Conversion" shall have the meaning set forth in Section 4(a)
hereof.

     "Original Issuance Date" shall mean the date of the first issuance of this
Debenture regardless of the number of transfers hereof.

     Section 2. Denominations of Debentures; Interest on Debentures. The
Debentures are exchangeable for an equal aggregate principal amount of
Debentures of different authorized denominations, as requested by the Holder
surrendering the same, but shall not be issuable in denominations of less than
integral multiplies of One Thousand Dollars (US$1,000.00). No service charge to
the Holder will be made for such registration of transfer or exchange.

     Section 3. Events of Default and Remedies.

     I. "Event of Default," when used herein, means any one of the following
events (whatever the reason and whether any such event shall be voluntary or
involuntary or effected by operation of law or pursuant to any judgment, decree
or order of any court, or any order, rule or regulation of any administrative or
governmental body):

     (a) any default in the payment of the principal of or interest on this
Debenture for more than five (5) Business Days after the same shall become due
and payable either at the Maturity Date, by acceleration, conversion, or
otherwise;

     (b) the Company shall fail to observe or perform any other covenant,
agreement or warranty contained in, or otherwise commit any breach of, this
Debenture, and such failure or breach shall not have been remedied within five
(5) Business Days of its receipt of notice of such failure or breach;

     (c) the occurrence of any event or breach or default by the Company under
the Purchase Agreement or any other Transaction Document and , if there is a
cure period, such failure or breach shall not have been remedied within the cure
period provided for therein;

     (d) the Company or any of its Subsidiaries shall commence a voluntary case
under the United States Bankruptcy Code as now or hereafter in effect or any
successor thereto (the "Bankruptcy Code"); or an involuntary case is commenced
against the Company under the Bankruptcy Code and the petition is not
controverted within thirty (30) days, or is not dismissed within sixty (60)
days, after commencement of the case; or a "custodian" (as defined in the
Bankruptcy Code) is appointed for, or takes charge of, all or any substantial
part of the property of the Company or the Company commences any other
proceeding under any reorganization, arrangement, adjustment of debt, relief of
debtors, dissolution, insolvency or liquidation or similar law of any
jurisdiction whether now or hereafter in effect relating to the Company or there
is commenced against the Company any such proceeding which remains undismissed
for a period of sixty (60) days; or the Company is adjudicated insolvent or
bankrupt; or any order of relief or other order approving any such case or
proceeding is entered; or the Company suffers any appointment of any custodian
or the like for it or any substantial part of its property which continues
undischarged

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or unstayed for a period of thirty (30) days; or the Company makes a general
assignment for the benefit of creditors; or the Company shall fail to pay, or
shall state in writing that it is unable to pay its debts generally as they
become due; or the Company shall call a meeting of its creditors with a view to
arranging a composition or adjustment of its debts; or the Company shall by any
act or failure to act indicate its consent to, approval of or acquiescence in
any of the foregoing; or any corporate or other action is taken by the Company
for the purpose of effecting any of the foregoing;

     (e) the Company shall default in any of its obligations under any mortgage,
indenture or instrument under which there may be issued, or by which there may
be secured or evidenced, any indebtedness of the Company in an amount exceeding
One Hundred Thousand Dollars ($100,000.00), whether such indebtedness now exists
or shall hereafter be created and such default shall result in such indebtedness
becoming or being declared due and payable prior to the date on which it would
otherwise become due and payable;

     (f) the Company shall have its Common Stock deleted or delisted, as the
case may be, from the AMEX, OTCBB or other national securities exchange or
market on which such Common Stock is listed for trading or suspended from
trading thereon, and shall not have its Common Stock listed or relisted on the
same or another national securities exchange, market, or the OTCBB or have such
suspension lifted, as the case may be, within ten (10) Trading Days of such
deletion or delisting;

     (g) notwithstanding anything herein to the contrary, but subject to the
limitations set forth in the Debentures and Section 4.14 of the Purchase
Agreement, the Company shall fail to deliver to the Escrow Agent share
certificates representing the shares of Common Stock to be issued upon
conversion of the Debentures within five (5) Business Days after to the
Company's receipt of notice from the Escrow Agent to the Company that additional
shares of Common Stock are required to be placed in escrow pursuant to Section
4.14 of the Purchase Agreement, Article 2 of the Escrow Agreement, and/or
Section 4(b) of this Debenture;

     (h) the Company shall issue a press release, or otherwise make publicly
known, that it is not honoring a properly executed and duly delivered Notice of
Conversion complying with the terms of this Debenture, the Purchase Agreement
and the Escrow Agreement, for any reason whatsoever; and

     (i) the Company issues or enters into an agreement to issue any floorless
convertible security, any equity line of credit, or any security issued pursuant
to Rule 504 of Regulation D promulgated under the Securities Act, other than to
the Purchaser or any of its Affiliates or assigns, during the period commencing
on the date hereof and ending on the four month anniversary of the Post-Closing
Date. Except as specifically set forth above, the Company may engage in any
other debt or equity financing during such four month period.

     (j) the Company issues or enters into an agreement to issue additional
equity or debt financings without complying with Section 4.17(b) of the Purchase
Agreement.

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     II. (a) If any Event of Default occurs, and continues beyond a cure period,
if any, then the Holder may, by written notice to the Company, accelerate all of
the payments due under this Debenture by declaring all amounts so due under this
Debenture, whereupon the same shall become immediately due and payable without
presentment, demand, protest or other notice of any kind, all of which are
waived by the Company, notwithstanding anything contained herein to the
contrary, and the Holder may immediately and without expiration of any
additional grace period enforce any and all of its rights and remedies hereunder
and all other remedies available to it under applicable law. Such declaration
may be rescinded and annulled by the Holder at any time prior to payment
hereunder. No such rescission or annulment shall affect any subsequent Event of
Default or impair any right consequent thereon. This shall include, but not be
limited to the right to temporary, preliminary and permanent injunctive relief
without the requirement of posting any bond or undertaking.

     (b) The Holder may thereupon proceed to protect and enforce its rights
either by suit in equity and/or by action at law or by other appropriate
proceedings whether for the specific performance (to the extent permitted by
law) of any covenant or agreement contained in this Debenture or in aid of the
exercise of any power granted in this Debenture, and proceed to enforce the
payment of any of the Debentures held by it, and to enforce any other legal or
equitable right of such Holder.

     (c) Except as expressly provided for herein, the Company specifically
waives all rights it may have (A) to notice of nonpayment, notice of default,
demand, presentment, protest and notice of protest with respect to any of the
obligations hereunder or the shares of Common Stock and (B) notice of acceptance
hereof or of any other action taken in reliance hereon, notice and opportunity
to be heard before the exercise by the Holder of the remedies of self-help,
set-off, or other summary procedures and all other demands and notices of any
type or description except for cure periods, if any.

     (d) As a non-exclusive remedy, upon the occurrence of an Event of Default,
the Holder may convert the remaining principal amount of the Debentures and
accrued interest thereon at the lesser of the Fixed Conversion Price or the
Floating Conversion Price upon giving a Notice of Conversion to the Company.
Except as otherwise provided herein, the Company shall not have the right to
object to the conversion or the calculation of the applicable conversion price,
absent manifest error and the Escrow Agent shall release the shares of Common
Stock from escrow two (2) Business Days after upon notifying the Company of the
conversion.

     III. To effectuate the terms and provision of this Debenture, the Holder
may give notice of any default to the Attorney-in-Fact as set forth herein and
give a copy of such notice to the Company and its counsel, simultaneously, and
request the Attorney-in-Fact to comply with the terms of this Debenture and the
Purchase Agreement and all agreements entered into pursuant to the Purchase
Agreement on behalf of the Company.

                                      A1-5

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     Section 4. Conversion.

     (a) Except as otherwise set forth herein or in the Purchase Agreement, the
unpaid principal amount of this Debenture shall be convertible into shares of
Common Stock at the Conversion Ratio as defined above, and subject to the
Limitation on Conversion described in Section 4.18 of the Purchase Agreement and
provided that the Company shall never be required to issue more than an
aggregate of 5,000,000 shares of Common Stock (as adjusted for stock splits,
reverse stock splits and the like) unless such shares are issued in compliance
with all applicable Shareholder Approval Rules (as defined in the Purchase
Agreement), at the option of the Holder, in whole or in part, at any time,
commencing on the Original Issuance Date. Such shares of Common Stock shall be
without any restriction and freely tradable pursuant to Rule 504 of Regulation D
of the Securities Act. Any conversion under this Section 4(a) shall be for a
minimum principal amount of $1,000.00 of the Debentures plus the interest
accrued and due thereon. The Holder shall effect conversions by surrendering the
Debenture to be converted to the Escrow Agent, together with the form of notice
attached hereto as Appendix I ("Notice of Conversion") in the manner set forth
in Section 4(j) hereof. Each Notice of Conversion shall specify the principal
amount of Debentures to be converted and the date on which such conversion is to
be effected (the "Conversion Date") which date shall not be less than two (2)
Business Days after the date on which the Notice of Conversion is delivered to
the Escrow Agent. Subject to the last paragraph of Section 4(b) hereof, each
Notice of Conversion, once given, shall be irrevocable. If the Holder is
converting less than all of the principal amount represented by the Debentures
tendered by the Holder in the Notice of Conversion, the Company shall deliver to
the Holder a new Debenture for such principal amount as has not been converted
within two (2) Business Days of the Conversion Date. In the event that the
Escrow Agent holds the Debentures on behalf of the Holder, the Company agrees
that in lieu of surrendering the Debentures upon every partial conversion, the
Escrow Agent shall give the Company and the Holder written notice of the amount
of the Debentures left unconverted. Upon conversion in full of the Debentures or
upon the Maturity Date, the Escrow Agent shall return the Debentures and the
Escrow Shares, if any, to the Company for cancellation.

     (b) Not later than two (2) Business Days after the Conversion Date, the
Escrow Agent shall deliver to the Holder (i) a certificate or certificates
representing the number of shares of Common Stock being acquired upon the
conversion of the Debentures, and once the Debentures so converted in part shall
have been surrendered to the Company, the Company shall deliver to the Holder
Debentures in the principal amount of the Debentures not yet converted;
provided, however, that the Company shall not be obligated to issue certificates
evidencing the shares of Common Stock issuable upon conversion of the
Debentures, until the Debentures are either delivered for conversion to the
Escrow Agent or the Company or any transfer agent for the Debentures or Common
Stock, or the Holder notifies the Company that such Debentures have been lost,
stolen or destroyed and provides an affidavit of loss and an agreement
reasonably acceptable to the Company indemnifying the Company from any loss
incurred by it in connection with such loss, theft or destruction. In the case
of a conversion pursuant to a Notice of Conversion, if such certificate or
certificates are not delivered by the date required under this Section 4(b), the
Holder shall be entitled, upon providing written notice to the Company at any
time on or before its receipt of such certificate or certificates thereafter, to
rescind such conversion, in which event, the Company shall immediately return
the Debentures tendered for conversion.

                                      A1-6

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     Subject to any limitations set forth in the Purchase Agreement, including
Section 4.14(e), the Company agrees that at any time the conversion price of the
Debentures are such that the number of Escrow Shares is less than 200% of the
Full Conversion Shares, upon five (5) Business Days of the Company's receipt of
notice of such circumstance from the Purchaser and/or the Escrow Agent, the
Company shall issue share certificates in the name of the Purchaser and deliver
the same to the Escrow Agent, in such number that the new number of Escrow
Shares is equal to 200% of the Full Conversion Shares.

     (c) (i) The conversion price for the Debentures in effect on any Conversion
Date shall be the lesser of (a) the lesser of $0.30 or one hundred twenty-five
percent (125%) of the average of the closing bid prices per share of the Common
Stock during the five (5) Trading Days immediately preceding the Closing (as
defined in the Purchase Agreement) (the "Fixed Conversion Price") or (b) one
hundred percent (100%) of the average of the three (3) lowest closing bid prices
per share of the Common Stock during the forty (40) Trading Days immediately
preceding the Conversion Date (the "Floating Conversion Price"); provided,
however, that the aggregate maximum number of shares of Common Stock that the
First Debenture A, First Debenture B and Second Debenture may be converted into
shall be Five Million (5,000,000) shares (the "Maximum Conversion"); and further
provided, however, that upon the Maximum Conversion, the Company may, at its
option (a) increase the Maximum Conversion or (b) redeem the unconverted amount
of the First Debenture A, First Debenture B and Second Debenture in whole or in
part at one hundred forty percent (140%) of the unconverted amount of such
Debentures being redeemed plus accrued interest thereon. For purposes of
determining the closing bid price on any day, reference shall be to the closing
bid price for a share of Common Stock on such date on the American Stock
Exchange (or such other exchange, market, or other system that the Common Stock
is then traded on), as reported on Bloomberg, L.P. (or similar organization or
agency succeeding to its functions of reporting prices).

          (ii) If the Company, at any time while any of the Debentures are
outstanding, (a) shall pay a stock dividend or otherwise make a distribution or
distributions on shares of its Common Stock payable in shares of its capital
stock (whether payable in shares of its Common Stock or of capital stock of any
class), (b) subdivide outstanding shares of Common Stock into a larger number of
shares, (c) combine outstanding shares of Common Stock into a smaller number of
shares, or (d) issue by reclassification any shares of capital stock of the
Company, the Fixed Conversion Price as applied in Section 4(c)(i) shall be
multiplied by a fraction, the numerator of which shall be the number of shares
of Common Stock of the Company outstanding immediately before such event and the
denominator of which shall be the number of shares of Common Stock outstanding
immediately after giving effect to such event. Any adjustment made pursuant to
this Section 4(c)(ii) shall become effective immediately after the record date
for the determination of stockholders entitled to receive such dividend or
distribution and shall become effective immediately after the effective date in
the case of a subdivision, combination or reclassification, provided that no
adjustment shall be made if the Company does not complete such dividend,
distribution, subdivision, combination or reclassification.

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          (iii) If, at any time while any of the Debentures are outstanding, the
Company issues or sells shares of Common Stock, or options, warrants or other
rights to subscribe for or purchase shares of Common Stock (excluding shares of
Common Stock issuable upon the conversion of the Debentures or upon the exercise
of options, warrants or conversion rights granted prior to the date hereof) and
at a price per share less than the Per Share Market Value (as defined in the
Purchase Agreement) of the Common Stock at the issue date mentioned below, the
Fixed Conversion Price shall be multiplied by a fraction, the numerator of which
shall be the number of shares of Common Stock (excluding treasury shares, if
any) outstanding on the date of issuance of such shares, options, warrants or
rights plus the number of shares which the aggregate offering price of the total
number of shares so offered would purchase at such Per Share Market Value, and
the denominator of which shall be the number of shares of Common Stock
(excluding treasury shares, if any) outstanding on the date of issuance of such
options, rights or warrants plus the number of additional shares of Common Stock
offered for subscription or purchase. Such adjustment shall be made whenever
such options, rights or warrants are issued (and if such adjustment is made, no
further adjustment will be made when such options, rights or warrants are
exercised), and shall become effective immediately after the record date for the
determination of stockholders entitled to receive such options, rights or
warrants. However, upon the expiration of any options, right or warrant to
purchase Common Stock, the issuance of which resulted in an adjustment in the
conversion price designated in Section 4(c)(i) hereof pursuant to this Section
4(c)(iii), if any such options, right or warrant shall expire and shall not have
been exercised, the Fixed Conversion Price shall immediately upon such
expiration be recomputed and effective immediately upon such expiration be
increased to the price which it would have been (but reflecting any other
adjustments in the conversion price made pursuant to the provisions of this
Section 4 after the issuance of such rights or warrants) had the adjustment of
the conversion price made upon the issuance of such options, rights or warrants
been made on the basis of offering for subscription or purchase only that number
of shares of Common Stock actually purchased upon the exercise of such options,
rights or warrants actually exercised. There will be no adjustment under this
Section 4(c)(iii) if Common Stock is issued due to the exercise of (x) employee
stock options that were issued to such employee, or (y) other options, warrants
or rights to subscribe for or purchase that, in any case, are issued at an
exercise or subscription price equal to Per Share Market Value.

          (iv) If, at any time while Debentures are outstanding, the Company
distributes to all holders of Common Stock (and not to holders of Debentures)
evidences of Company indebtedness or assets, or rights or warrants to subscribe
for or purchase any security (excluding those referred to in Section 4(c)(iii)
hereof), then, in each such case, the conversion price at which each Debenture
then outstanding shall thereafter be convertible shall be determined by
multiplying (A) the Fixed Conversion Price in effect immediately prior to the
record date fixed for determination of stockholders entitled to receive such
distribution by a fraction, the numerator of which shall be the Per Share Market
Value of the Common Stock determined as of the record date mentioned above less
the then fair market value at such record date of the portion of such assets or
evidence of indebtedness so distributed applicable to one outstanding share of
Common Stock as determined by the Board of Directors in good faith and the
denominator of which shall be the Per Share Market Value of the Common Stock on
such record date; provided, however, that in the event of a distribution
exceeding ten percent (10%) of the net assets of the Company, such fair market
value shall be determined by a nationally recognized or major regional
investment banking firm or firm of

                                      A1-8

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independent certified public accountants of nationally recognized standing
(which may be the firm that regularly examines the financial statements of the
Company) (an "Appraiser") selected in good faith by the holders of a majority of
the principal amount of the Debentures then outstanding; and provided, further,
that the Company, after receipt of the determination by such Appraiser, shall
have the right to select an additional Appraiser, in which case such fair market
value shall be equal to the average of the determinations by each such
Appraiser. In either case the adjustments shall be described in a statement
provided to the Holder and all other holders of Debentures of the portion of
assets or evidences of indebtedness so distributed or such subscription rights
applicable to one share of Common Stock. Such adjustment shall be made whenever
any such distribution is made and shall become effective immediately after the
record date mentioned above. Holders shall pay all fees and expenses of any
Appraiser selected by them and Company shall pay all fees and expenses of any
Appraiser selected by it.

          (v) All calculations under this Section 4 shall be made to the nearest
1/1000th of a cent or the nearest 1/1000th of a share, as the case may be. Any
calculation equal to or over .005 shall be rounded up to the next cent or share
and any calculation less than .005 shall be rounded down to the previous cent or
share.

          (vi) In the event the conversion price is not adjusted pursuant to
Section 4(c)(ii) or (v), within two (2) Business Days following the occurrence
of an event described therein and, in the case of Section 4c(iv), within three
(3) Business Days following the determination of the fair market value by the
Appraiser(s), the Holder shall have the right to require the Company to redeem
the Debentures at 140% of the Purchase Price and simultaneously pay such amount
and all accrued interest and dividends to the Holder pursuant to the written
instructions provided by the Holder. The Company will have two (2) Business Days
to make the appropriate adjustment from the time the Company is provided with
written notice from the Holder of a failure to comply with this Section 4.

          (vii) Whenever the Fixed Conversion Price is adjusted pursuant to
Section 4(c)(ii),(iii) or (iv), the Company shall within two (2) Business Days
after the determination of the new Fixed Conversion Price mail and fax (in the
manner set forth in Section 4(j) hereof) to the Holder and to each other holder
of Debentures, a notice ("Company Notice of Conversion Price Adjustment")
setting forth the Fixed Conversion Price after such adjustment and setting forth
a brief statement of the facts requiring such adjustment.

          (viii) In case of any reclassification of the Common Stock, any
consolidation or merger of the Company with or into another person, the sale or
transfer of all or substantially all of the assets of the Company or any
compulsory share exchange pursuant to which the Common Stock is converted into
other securities, cash or property, then each holder of Debentures then
outstanding shall have the right thereafter to convert such Debentures only into
the shares of stock and other securities and property receivable upon or deemed
to be held by holders of Common Stock following such reclassification,
consolidation, merger, sale, transfer or share exchange (except in the event the
property is cash, then the Holder shall have the right to convert the Debentures
and receive cash in the same manner as other stockholders), and the Holder shall
be entitled upon such event to receive such amount of securities or property as
the holder of shares of the Common Stock into which such Debentures could have
been converted immediately prior to such reclassification, consolidation,

                                      A1-9

<PAGE>

merger, sale, transfer or share exchange would have been entitled. The terms of
any such consolidation, merger, sale, transfer or share exchange shall include
such terms so as to continue to give to the Holder the right to receive the
securities or property set forth in this Section 4(c)(viii) upon any conversion
following such consolidation, merger, sale, transfer or share exchange. This
provision shall similarly apply to successive reclassifications, consolidations,
mergers, sales, transfers or share exchanges;

          (ix) If:

               (A)  the Company shall declare a dividend (or any other
                    distribution) on its Common Stock; or

               (B)  the Company shall declare a special non-recurring cash
                    dividend redemption of its Common Stock; or

               (C)  the Company shall authorize the grant to all holders of the
                    Common Stock rights or warrants to subscribe for or purchase
                    any shares of capital stock of any class or of any rights;
                    or

               (D)  the approval of any stockholders of the Company shall be
                    required in connection with any reclassification of the
                    Common Stock of the Company (other than a subdivision or
                    combination of the outstanding shares of Common Stock), any
                    consolidation or merger to which the Company is a party, any
                    sale or transfer of all or substantially all of the assets
                    of the Company, or any compulsory share exchange whereby the
                    Common Stock is converted into other securities, cash or
                    property; or

               (E)  the Company shall authorize the voluntary or involuntary
                    dissolution, liquidation or winding-up of the affairs of the
                    Company;

then the Company shall cause to be filed at each office or agency maintained for
the purpose of conversion of Debentures, and shall cause to be mailed and faxed
to the Holder and each other holder of the Debentures at their last addresses
and facsimile number set forth in the Debenture Register at least twenty (20)
calendar days prior to the applicable record or effective date hereinafter
specified, a notice stating (x) the date on which a record is to be taken for
the purpose of such dividend, distribution, redemption, rights or warrants, or
if a record is not to be taken, the date as of which the holders of Common Stock
of record to be entitled to such dividend, distributions, redemption, rights or
warrants are to be determined, or (y) the date on which such reclassification,
consolidation, merger, sale, transfer, share exchange, dissolution, liquidation
or winding-up is expected to become effective, and the date as of which it is
expected that holders of Common Stock of record shall be entitled to exchange
their shares of Common Stock for securities or other property deliverable upon
such reclassification, consolidation, merger, sale, transfer, share exchange,
dissolution, liquidation or winding-up; provided, however, that the failure to
mail such notice or any defect therein or in the

                                      A1-10

<PAGE>

mailing thereof shall not affect the validity of the corporate action required
to be specified in such notice.

     (d) If at any time conditions shall arise by reason of action or failure to
act by the Company, which action or failure to act, in the opinion of the Board
of Directors of the Company, is not adequately covered by the other provisions
hereof and which the Board of Directors of the Company determines in good faith
is likely to materially and adversely affect the rights of the Holder and all
other holders of Debentures (different or distinguishable from the effect
generally on rights of holders of any class of the Company's capital stock), the
Company shall, at least twenty (20) calendar days prior to the effective date of
such action, mail and fax a written notice to each holder of Debentures briefly
describing the action contemplated, and an Appraiser selected by the holders of
majority in principal amount of the outstanding Debentures shall give its
opinion as to the adjustment, if any (not inconsistent with the standards
established in this Section 4 and the terms of the Purchase Agreement and the
Debentures), of the conversion price (including, if necessary, any adjustment as
to the securities into which Debentures may thereafter be convertible) and any
distribution which is or would be required to preserve without diluting the
rights of the holders of Debentures; provided, however, that the Company, after
receipt of the determination by such Appraiser, shall have the right to select
an additional Appraiser, in which case the adjustment shall be equal to the
average of the adjustments recommended by each such Appraiser. The Company shall
pay all fees and expenses of any Appraiser selected under this Section 4(d). The
Board of Directors of the Company shall make the adjustment recommended
forthwith upon the receipt of such opinion or opinions or the taking of any such
action contemplated, as the case may be; provided, however, that no such
adjustment of the conversion price shall be made which, in the opinion of the
Appraiser(s) giving the aforesaid opinion or opinions, would result in an
increase of the conversion price above the conversion price then in effect.

     (e) Subject to the terms and limitations set forth in the Debentures and
the Purchase Agreement, including without limitation, Sections 4.14, 4.28 and
4.33 thereof, the Company covenants and agrees that it shall, at all times,
reserve and keep available out of its authorized and unissued Common Stock
solely for the purpose of issuance upon conversion of the Debentures as herein
provided, free from preemptive rights or any other actual contingent purchase
rights of persons other than the Holder of the Debentures, two (2) times such
number of shares of Common Stock as shall be issuable (taking into account the
adjustments and restrictions of Section 4(c) and Section 4(d) hereof) upon the
conversion of the aggregate principal amount of the outstanding Debentures,
provided, however, that the Company shall not be required to reserve and keep
available any shares pursuant to this Section 4(e) in violation of any
applicable Shareholder Approval Rules. The Company covenants that, subject to
the limitations set forth in this Section 4(e), all shares of Common Stock that
shall be issuable upon conversion of the Debentures shall, upon issuance, be
duly and validly authorized and issued and fully paid and non-assessable.

     (f) No fractional shares of Common Stock shall be issuable upon a
conversion hereunder and the number of shares to be issued shall be rounded up
to the nearest whole share. If a fractional share interest arises upon any
conversion hereunder, the Company shall eliminate such fractional share interest
by issuing to the Holder an additional full share of Common Stock.

                                      A1-11

<PAGE>

     (g) The issuance of a certificate or certificates for shares of Common
Stock upon conversion of the Debentures shall be made without charge to the
Holder for any documentary stamp or similar taxes that may be payable in respect
of the issuance or delivery of such certificate, provided that the Company shall
not be required to pay any tax that may be payable in respect of any transfer
involved in the issuance and delivery of any such certificate upon conversion in
a name other than that of the Holder and the Company shall not be required to
issue or deliver such certificates unless or until the person or persons
requesting the issuance thereof shall have paid to the Company the amount of
such tax or shall have established to the satisfaction of the Company that such
tax has been paid.

     (h) The Debentures converted into Common Stock shall be canceled upon
conversion.

     (i) On the Maturity Date, the unconverted principal amount of the
Debentures and all interest due thereon shall either be paid off in full by the
Company or, if payment in full is not received within two (2) Business Days
after the Maturity Date, convert automatically into shares of Common Stock at
the lesser of the Fixed Conversion Price and the Floating Conversion Price as
set forth in Section 4(c)(i).

     (j) Each Notice of Conversion shall be given by facsimile to the Escrow
Agent no later than 4:00 pm New York time on any Business Day. Upon receipt of
such Notice of Conversion, the Escrow Agent shall forward such Notice of
Conversion to the Company by facsimile by 6:00 p.m. New York time on the day on
which the Escrow Agent receives the Notice of Conversion, at the facsimile
telephone number and address of the principal place of business of the Company.
Any such notice shall be deemed given and effective upon the transmission of
such facsimile at the facsimile telephone number specified in the Purchase
Agreement (with printed confirmation of transmission). In the event that the
Escrow Agent receives the Notice of Conversion after 4:00 p.m. New York time or
the Company receives the Notice of Conversion after 6:00 p.m. New York time on
such day, or the Holder receives the Company Notice of Conversion Price
Adjustment after 6:00 p.m. New York time, any such notice shall be deemed to
have been given on the next Business Day.

     Section 5. Redemption of Debentures. (a) At any time after the Execution
Date, so long as no Event of Default has occurred and, if a cure period is
provided, has not been cured, the Company shall have the option to redeem any
unconverted amount of the Debentures, either in part or whole, upon no less than
thirty (30) days written notice thereof given to the Holder with a copy to the
Escrow Agent (the "Redemption Notice"), at one hundred forty percent (140%) of
the unconverted amount of the Debentures plus accrued interest thereon (the
"Redemption Price"). Notwithstanding anything contained herein to the contrary,
if the Company decides to redeem the outstanding principal amount of the
Debenture under the second proviso in the first sentence of Section 4(c)(i) of
this Debenture, the Company shall have three (3) Business Days from their
decision to redeem the Debenture in order to effectuate the redemption of such
principal amount of the outstanding Debenture.

     (b) Within three (3) Business Days prior to the date fixed for redemption
in the Redemption Notice, the Company shall deposit the Redemption Price by wire
transfer to the IOLA account of the Escrow Agent. Upon receipt of the Redemption
Price, on such redemption date, the

                                      A1-12

<PAGE>

Escrow Agent shall release the Redemption Price to the Holder and return the
remaining Debentures, Escrow Shares and Underlying Shares to the Company.

     (c) In the event that the Company fails to deposit the Redemption Price in
the Escrow Agent's IOLA account number within the time allocated in Section 5(b)
hereof, then the redemption shall be declared null and void.

     Section 6. Intentionally Omitted.

     Section 7. Absolute Payment Obligation; Limitation on Prepayment. Except as
expressly provided herein, no provision of this Debenture shall alter or impair
the obligation of the Company, which is absolute and unconditional, to pay the
principal of, and interest on, this Debenture at the time, place, and rate, and
in the coin or currency, herein prescribed. This Debenture is a direct
obligation of the Company. This Debenture ranks pari passu with all other
Debentures now or hereafter issued under the terms set forth herein. The Company
may not prepay any portion of the outstanding principal amount on the Debentures
except in accordance with the Purchase Agreement or Sections 4(c)(i) or 5
hereof.

     Section 8. No Rights of Stockholders. Except as otherwise provided herein
or in the Purchase Agreement, this Debenture shall not entitle the Holder to any
of the rights of a stockholder of the Company, including without limitation, the
right to vote on or consent to any action, to receive dividends and other
distributions, or to receive any notice of, or to attend, meetings of
stockholders or any other proceedings of the Company, unless and to the extent
converted into shares of Common Stock in accordance with the terms hereof.

     Section 9. Loss, Theft, Mutilation or Destruction. If this Debenture shall
be mutilated, lost, stolen or destroyed, the Company shall execute and deliver,
in exchange and substitution for and upon cancellation of a mutilated Debenture,
or in lieu of or in substitution for a lost, stolen or destroyed Debenture, a
new Debenture for the principal amount of this Debenture so mutilated, lost,
stolen or destroyed but only upon receipt of an affidavit of such loss, theft or
destruction of such Debenture, and, if requested by the Company, an agreement to
indemnity the Company in form reasonably acceptable to the Company.

     Section 10. Governing Law. This Debenture shall be governed by and
construed and enforced in accordance with the internal laws of the State of New
York without regard to the principles of conflicts of law thereof. Any action to
enforce the terms of this Debenture, the Purchase Agreement or any other
Transaction Document shall be exclusively brought in the state and/or federal
courts in the state and county of New York. Service of process in any action by
the Holder to enforce the terms of this Debenture may be made by serving a copy
of the summons and complaint, in addition to any other relevant documents, by
commercial overnight courier to the Company at its address set forth in the
Purchase Agreement.

     Section 11. Notices. Any notice, request, demand, waiver, consent, approval
or other communication which is required or permitted to be given to any party
hereunder shall be in writing and shall be deemed duly given only if delivered
to the party personally or sent to the party by facsimile upon electronic
confirmation receipt (promptly followed by a hard-copy delivered in accordance
with this Section 12) or three days after being mailed by registered or
certified mail

                                      A1-13

<PAGE>

(return receipt requested), with postage and registration or certification fees
thereon prepaid, or if sent by nationally recognized overnight courier, one day
after being mailed, addressed to the party at its address as set forth in
Section 7.3 of the Purchase Agreement or such other address as may be designated
hereafter by notice given pursuant to the terms of this Section 11.

     Section 12. Waiver. Any waiver by the Company or the Holder of a breach of
any provision of this Debenture shall not operate as or be construed to be a
waiver of any other breach of such provision or of any breach of any other
provision of this Debenture. The failure of the Company or the Holder to insist
upon strict adherence to any term of this Debenture on one or more occasions
shall not be considered a waiver or deprive that party of the right thereafter
to insist upon strict adherence to that term or any other term of this Debenture
in any other occasion. Any waiver must be in writing.

     Section 13. Invalidity. If any provision of this Debenture is held to be
invalid, illegal or unenforceable, the balance of this Debenture shall remain in
effect, and if any provision is held to be inapplicable to any person or
circumstance, it shall nevertheless remain applicable to all other persons and
circumstances.

     Section 14. Payment Dates. Whenever any payment or other obligation
hereunder shall be due on a day other than a Business Day, such payment shall be
made on the next following Business Day.

     Section 15. Transfer; Assignment. This Debenture may not be transferred or
assigned, in whole or in part, at any time, except in compliance by the
transferor and the transferee with applicable federal and state securities laws.

     Section 16. Fees of Enforcement. In the event any Party commences legal
action to enforce its rights under this Debenture, the non-prevailing party
shall pay all reasonable costs and expenses (including but not limited to
reasonable attorney's fees, accountant's fees, appraiser's fees and
investigative fees) incurred in enforcing such rights.

                            [Signature Page Follows]

                                      A1-14

<PAGE>

     IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed by an officer thereunto duly authorized as of the date first above
indicated.

                                OPHTHALAMIC SOLUTIONS, INC.


Attest:                         By: /s/ Jehu Hand
        ---------------------       --------------------------------------------
                                    Name: Jehu Hand
                                    Title: President and Chief Executive Officer

                                      A1-15

<PAGE>

                                   APPENDIX I

                              NOTICE OF CONVERSION
                          AT THE ELECTION OF THE HOLDER

(To be Executed by the Registered Holder
in order to Convert the Debentures)

Except as provided by Section 4(b) of the Debentures, the undersigned hereby
irrevocably elects to convert the attached Debenture into shares of Common
Stock, par value $0.001 per share (the "Common Stock"), of Ophthalmic Solutions,
Inc. (the "Company"), or, if a Merger (as defined in the Debenture) has
occurred, into shares of MP Common Stock (as defined in the Debenture) according
to the provisions hereof, as of the date written below. If shares are to be
issued in the name of a person other than undersigned, the undersigned will pay
all transfer taxes payable with respect thereto and is delivering herewith such
certificates and opinions as reasonably requested by the Company in accordance
therewith. A fee of $350 will be charged by the Escrow Agent to the Holder for
each conversion. No other fees will be charged to the Holder, except for
transfer taxes, if any.

Conversion calculations:
                                ------------------------------------------------
                                Date to Effect Conversion

                                ------------------------------------------------
                                Principal Amount of Debentures to be Converted

                                ------------------------------------------------
                                Interest to be Converted or Paid

                                ------------------------------------------------
                                Applicable Conversion Price (Pursuant to Section
                                4(c)(v))

                                ------------------------------------------------
                                Number of Shares to be Issued Upon Conversion


                                ------------------------------------------------
                                Signature

                                ------------------------------------------------
                                Name

                                ------------------------------------------------
                                Address

                                      A1-16