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                                                                    EXHIBIT 10.1

                         DREXLER TECHNOLOGY CORPORATION
                                CERTIFICATION OF
                       AMENDMENT TO 1991 STOCK OPTION PLAN


         I, the undersigned, hereby certify that:

         1. I am a duly elected and acting Assistant Secretary of Drexler
Technology Corporation, a Delaware corporation (the "Company").

         2. On June 2, 1998, the Board of Directors of the Company approved,
subject to stockholder approval, an amendment to the Company's 1991 Stock Option
Plan (the "Plan") to increase the aggregate number of shares in the Plan by
480,000 shares, from 2,370,000 to 2,850,000 shares (the "Amendment").

         3. On September 25, 1998, the Amendment was approved by an affirmative
vote of the majority of stockholders represented in person or by proxy at the
Company's Annual Meeting of Stockholders.

         4. Under the EDGAR system of the Securities and Exchange Commission, a
copy of the Plan was most recently filed in its entirety as Exhibit 10.6.6 to
the Company's Report on Form 10-K for the fiscal year ended March 31, 1998.

         5. By means of this Exhibit 10.1 to the Company's Report on Form 10-Q
for the fiscal second quarter ended September 30, 1998, Sections 2 and 9 of the
Plan, as amended, are filed as shown below:

         Section 2 of the Plan is amended to read as follows:
   
         2. STOCK SUBJECT TO PLAN. The Company shall reserve 2,850,000 shares of
its $0.01 par value Common Stock (hereinafter called the "Shares") to be issued
upon exercise of the options which may be granted from time to time under this
Plan. In addition, those of the shares reserved for issuance under the Company's
1986 Stock Option Plan on March 1, 1991, (i) which were not then subject to
outstanding options or (ii) which were then subject to outstanding options which
subsequently lapse, shall also be reserved for issuance pursuant to the exercise
of options granted from time to time under this Plan. As it may from time to
time determine, the Board of Directors of the Company (hereinafter called the
"Board") may authorize that the Shares may be comprised, in whole or in part, of
authorized but unissued shares of the Common Stock of the Company or of issued
shares which have been reacquired. If options granted under this Plan terminate
or expire before being exercised in whole or in part, the Shares subject to
those options which have not been issued may be subjected to subsequent options
granted under this Plan.
    

         The first paragraph of Section 9 of the Plan is amended to read as
follows:
   
         9. EFFECTIVE DATE AND TERMINATION OF PLAN. This Plan was adopted by the
Board of Directors on November 30, 1990, and was approved by the shareholders on
March 1, 1991. This Plan has been amended from time as permitted hereunder, most
recently on June 2, 1998. The Board may terminate this Plan at any time. If not
earlier terminated, this Plan shall terminate November 30, 2000. Termination of
this Plan will not affect rights and obligations theretofore granted and then in
effect.
    

Dated:   September 25, 1998


                                            /s/Johanna P. Protsik
                                            ------------------------------------
                                            Johanna P. Protsik
                                            Assistant Secretary