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                                                                     EXHIBIT 4.1

                      SECOND AMENDMENT TO RIGHTS AGREEMENT

        This Second Amendment to Rights Agreement (this "Amendment"), is entered
into by and between Ophthalmic Imaging Systems, a California Corporation (the
"Company") and American Securities Transfer, Inc. (the "Rights Agent"), as
transfer agent, and shall be deemed effective as of October 20, 1999 (the
"Effective Date").

                                    RECITALS

        WHEREAS, the Company and Rights Agent entered into a Rights Agreement
dated December 31, 1997 (the "Rights Agreement"), as amended from time to time,
to provide for the distribution of preferred share purchase rights for each
share of Company common stock outstanding as of January 2, 1998, which rights
represent the right to purchase one one-hundredth of a preferred share of the
Company upon a Distribution Date, as defined therein, and subject to the terms
and conditions set forth in the Rights Agreement;

        WHEREAS, the Company, Premier Laser Systems, Inc. ("Premier") and
Ophthalmic Acquisition Corporation, a California corporation and a subsidiary of
Premier ("Premier Sub") have entered into an Agreement and Plan of
Reorganization (the "Merger Agreement"), whereby, upon requisite shareholder
approval, OIS will be merged with and into Premier Sub (the "Merger"), with OIS
becoming the surviving corporation and each share of OIS common stock converting
into shares of Premier Class A common stock at the exchange ratio set forth in
the Merger Agreement;

        WHEREAS, Premier has held approximately 51% of the outstanding common
stock of OIS and therefore a majority vote since February 1998;

        WHEREAS, approximately thirty-five persons, including approximately
thirty current employees of OIS, presently hold approximately 1,600,000 options
to purchase OIS common stock at an exercise price ranging from $0.63 to $4.50
per share (the "Employee Options"), many of which are already vested;

        WHEREAS, the Company desires to sell to Premier, and Premier wishes to
purchase from Company, shares of the Company's Series B Preferred Stock (the
"Series B Stock") necessary to preserve Premier's majority vote despite the
exercise of Company stock options by one or more persons, and without triggering
the preferred share purchase rights under the Rights Agreement;

        WHEREAS, the Company's Board of Directors (the "Board") believes it is
in the best interest of the Company to amend the Rights Agreement to allow
Premier to acquire Series B Stock without triggering the preferred share
purchase rights under the Rights Agreement;

        WHEREAS, the Board believes it is in the best interest to amend the
Rights Agreement to allow Premier to acquire all of the Company's outstanding
common stock, but not less than all, without triggering the preferred share
purchase rights under the Rights Agreement, provided



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Premier acquires the Company, under the terms of the Merger Agreement, on or
before January 31, 2000;

        WHEREAS, the Company and the Rights Agent desire to amend the Rights
Agreement in accordance with Section 27 of the Rights Agreement to permit the
transactions contemplated by the Merger Agreement as well as the purchase of
Series B Stock without causing a Distribution Date under the terms of the Rights
Agreement; and

        WHEREAS, the Board has given its unanimous written consent in favor of
this Amendment pursuant to Section 307(b) of the California General Corporation
Law.

                                    AGREEMENT

        NOW, THEREFORE, in consideration of the foregoing recitals and the
mutual promises, covenants and conditions hereinafter set forth, the parties
hereto agree as follows:

                                    ARTICLE 1

                                   AMENDMENTS

        1.1     Amendments to Rights Agreement. The Rights Agreement is hereby
amended as follows:

                (a) Section 1(a) of the Rights Agreement is hereby deleted in
its entirety and replaced by the following:

                "(a) `ACQUIRING PERSON' shall mean any Person (as such term is
                hereinafter defined) who or which, together with all Affiliates
                and Associates (as such terms are hereinafter defined) of such
                Person, shall be the Beneficial Owner (as such term is
                hereinafter defined) of 20% or more of the Common Shares of the
                Company then-outstanding, but shall not include the Company, any
                Subsidiary (as such term is hereinafter defined) of the Company,
                any employee benefit plan of the Company or any Subsidiary of
                the Company, or any entity holding Common Shares for or pursuant
                to such plan. Notwithstanding the foregoing, Premier Laser
                Systems, Inc., a California corporation ("Premier") shall not be
                deemed an "Acquiring Person" under this Agreement; PROVIDED,
                HOWEVER, that if Premier does not acquire, on or before January
                31, 2000, all of the Common Shares of the Company
                then-outstanding under the terms and conditions set forth in the
                Agreement and Plan of Reorganization By and Among Premier Laser
                Systems, Inc., Ophthalmic Acquisition Corporation and Ophthalmic
                Imaging Systems, Inc. dated October 21, 1999 (the "Merger
                Agreement") or if the Merger Agreement is otherwise terminated
                by any party thereto prior to the Closing Date, as defined
                therein, then the term `ACQUIRING PERSON' shall have the meaning
                given to it in the February 25, 1998 amendment of this
                Agreement. Notwithstanding the foregoing, no Person shall become
                an "ACQUIRING PERSON" as a result of an acquisition of Common
                Shares of the Company



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                which, by reducing the number of shares outstanding, increases
                the proportionate number of shares Beneficially Owned by such
                Person to 20% or more of the Common Shares of the Company
                then-outstanding; PROVIDED, HOWEVER, that if a Person, other
                than the Company, any Subsidiary of the Company, any employee
                benefit plan of the Company or any Subsidiary of the Company, or
                any entity holding Common Shares for or pursuant to such plan,
                or Premier, should become the Beneficial Ownership of 20% or
                more of the Common Shares of the Company then-outstanding by
                reason of share purchases by the Company and shall, after such
                share purchases by the Company, become the Beneficial Owner of
                any additional Common Shares of the Company, then such Person
                shall be deemed to be an "ACQUIRING PERSON" for any purpose of
                this Agreement."

                (b) Section 1(f) of the Rights Agreement is hereby deleted in
its entirety and replaced by the following:

                "(f) `COMMON SHARES' when used with reference to the Company
                shall mean the shares of common stock, no par value per share,
                of the Company, and shall not mean the Company's Series B
                Preferred Stock. `COMMON SHARES' when used with reference to any
                Person other than the Company shall mean the capital stock (or
                equity interest) with the greatest voting power of such other
                Person or, if such other Person is a Subsidiary of another
                person, the Person or Persons which ultimately control such
                first-mentioned Person."

        1.2 Reference to and Effect on Rights Agreement. On and after the
Effective Date, each reference in the Rights Agreement to the term "Agreement,"
"hereof" or "herein" shall be deemed to refer to the Rights Agreement as amended
hereby. This Amendment and the amendments to the Rights Agreement effected
hereby shall be effective as of the Effective Date and, except as set forth
herein, the Rights Agreement shall remain in full force and effect and shall
otherwise be unaffected hereby.

                                    ARTICLE 2

                                  MISCELLANEOUS

        2.1 Headings. The headings in this Amendment are intended solely for
convenience and shall not be construed as limiting or expanding the terms of
this Amendment.

        2.2 Counterparts. This Amendment may be signed in any number of
counterparts with the same effect as if the signatures to each counterpart were
upon a single instrument. All counterparts shall be deemed an original of this
Agreement.



                            [SIGNATURE PAGE FOLLOWS]



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        IN WITNESS WHEREOF, the parties executed this Agreement to be effective
as of the date first written above.


                                        OPHTHALMIC IMAGING SYSTEMS

Attest: /s/ STEVEN C. LAGORIO           By: /s/ STEVEN R. VERDOONER
       ------------------------------      -------------------------------------
       Steven C. Lagorio,                  Steven R. Verdooner,
       Chief Financial Officer and         Chief Executive Officer and President
         Secretary

                                        AMERICAN SECURITIES TRANSFER, INC.

Attest: /s/ KELLIE GWINN                By: /s/ LAURA SISNEROS
       ------------------------------      -------------------------------------
       Kellie Gwinn,                       Laura Sisneros,
       Senior Vice President               Vice President