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                                                                 EXHIBIT 10.5.1


                         AMERICAN TECHNOLOGY CORPORATION

                             INCENTIVE STOCK OPTION

_______________________________, Optionee:

         AMERICAN TECHNOLOGY CORPORATION (the "Company"), pursuant to its 1997
Stock Option Plan (the "Plan"), has granted to you, the optionee named above, an
option to purchase shares of the common stock of the Company ("Common Stock").
This option is intended to qualify as an "incentive stock option" within the
meaning of Section 422 of the Internal Revenue Code of 1986, as amended (the
"Code").

         The grant hereunder is in connection with and in furtherance of the
Company's compensatory benefit plan for participation of the Company's employees
(including officers, directors and consultants). The grant of this option and
the issuance of shares upon the exercise of this option are intended to be
exempt from the securities qualification requirements of the California
Corporations Code pursuant to Section 25102(f) of that code. Defined terms not
explicitly defined in this agreement but defined in the Plan shall have the same
definitions as in the Plan.

         The details of your option are as follows:

         1. TOTAL NUMBER OF SHARES SUBJECT TO THIS OPTION. The total number of
shares of Common Stock subject to this option is ___________ (________).

         2. VESTING. Subject to the limitations contained herein, ___________
(_______) of the shares will vest (become exercisable) on _______, 19_______ and
_______ of the shares will then vest each month thereafter until either (i) you
cease to provide services to the Company for any reason, or (ii) this option
becomes fully vested.

         3. EXERCISE PRICE AND METHOD OF PAYMENT.

                  (a) EXERCISE PRICE. The exercise price of this option is
_________ ($______ ) per share, being not less than the fair market value of the
Common Stock on the date of grant of this option.

                  (b) METHOD OF PAYMENT. Payment of the exercise price per share
is due in full upon exercise of all or any part of each installment which has
accrued to you. You may elect, to the extent permitted by applicable statutes
and regulations, to make payment of the exercise price under one of the
following alternatives:

                           (i) Payment of the exercise price per share in cash
(including check) at the time of exercise;

                           (ii) Payment pursuant to a program developed under
Regulation T as promulgated by the Federal Reserve Board which, prior to the
issuance of Common Stock, results in either the receipt of cash (or check) by
the Company or the receipt of irrevocable instructions to pay the aggregate
exercise price to the Company from the sales proceeds;


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                           (iii) Provided that at the time of exercise the
Company's Common Stock is publicly traded and quoted regularly in the Wall
Street Journal, payment by delivery of already-owned shares of Common Stock,
held for the period required to avoid a charge to the Company's reported
earnings, and owned free and clear of any liens, claims, encumbrances or
security interests, which Common Stock shall be valued at its fair market value
on the date of exercise; or

                           (iv) Payment by a combination of the methods of
payment permitted by subparagraph 3(b)(i) through 3(b)(iii) above.

         4. WHOLE SHARES. This option may not be exercised for any number of
shares which would require the issuance of anything other than whole shares.

         5. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary
contained herein, this option may not be exercised unless the shares issuable
upon exercise of this option are then registered under the Securities Act of
1933, as amended (the "Act"), or, if such shares are not then so registered, the
Company has determined that such exercise and issuance would be exempt from the
registration requirements of the Act.

         6. TERM. The term of this option commences on ______________, 19
_______, the date of grant, and expires on _______________ (the "Expiration
Date," which date shall be no more than ten (10) years from date this option is
granted), unless this option expires sooner as set forth below or in the Plan.
In no event may this option be exercised on or after the Expiration Date. This
option shall terminate prior to the Expiration Date of its term as follows:
three (3) months after the termination of your Continuous Status as an Employee,
Director or Consultant with the Company or an Affiliate of the Company unless
one of the following circumstances exists:

                  (a) Your termination of Continuous Status as an Employee,
Director or Consultant is due to your disability. This option will then expire
on the earlier of the Expiration Date set forth above or twelve (12) months
following such termination of Continuous Status as an Employee, Director or
Consultant. You should be aware that if your disability is not considered a
permanent and total disability within the meaning of Section 422(c)(6) of the
Code, and you exercise this option more than three (3) months following the date
of your termination of employment, your exercise will be treated for tax
purposes as the exercise of a "nonstatutory stock option" instead of an
"incentive stock option."

                  (b) Your termination of Continuous Status as an Employee,
Director or Consultant is due to your death or your death occurs within three
(3) months following your termination of Continuous Status as an Employee,
Director or Consultant. This option will then expire on the earlier of the
Expiration Date set forth above or eighteen (18) months after your death.


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                  (c) If during any part of such three (3) month period you may
not exercise your option solely because of the condition set forth in paragraph
5 above, then your option will not expire until the earlier of the Expiration
Date set forth above or until this option shall have been exercisable for an
aggregate period of three (3) months after your termination of Continuous Status
as an Employee, Director or Consultant.

                  (d) If your exercise of the option within three (3) months
after termination of your Continuous Status as an Employee, Director or
Consultant with the Company or with an Affiliate of the Company would result in
liability under section 16(b) of the Securities Exchange Act of 1934, as
amended, then your option will expire on the earlier of (i) the Expiration Date
set forth above, (ii) the tenth (10th) day after the last date upon which
exercise would result in such liability or (iii) six (6) months and ten (10)
days after the termination of your Continuous Status as an Employee, Director or
Consultant with the Company or an Affiliate of the Company.

         However, this option may be exercised following termination of
Continuous Status as an Employee, Director or Consultant only as to that number
of shares as to which it was exercisable on the date of termination of
Continuous Status as an Employee, Director or Consultant under the provisions of
paragraph 2 of this option.

         In order to obtain the federal income tax advantages associated with an
"incentive stock option," the Code requires that at all times beginning on the
date of grant of the option and ending on the day three (3) months before the
date of the option's exercise, you must be an employee of the Company or an
Affiliate of the Company, except in the event of your death or permanent and
total disability. The Company has provided for continued vesting or extended
exercisability of your option under certain circumstances for your benefit, but
cannot guarantee that your option will necessarily be treated as an "incentive
stock option" if you provide services to the Company or an Affiliate of the
Company as a consultant or exercise your option more than three (3) months after
the date your employment with the Company and all Affiliates of the Company
terminates.

         7. REPRESENTATIONS. By executing this option agreement, you hereby
warrant and represent that you are acquiring this option for your own account
and that you have no intention of distributing, transferring or selling all or
any part of this option except in accordance with the terms of this option
agreement and Section 25102(f) of the California Corporations Code. You also
hereby warrant and represent that you have either (i) preexisting personal or
business relationships with the Company or any of its officers, directors or
controlling persons, or (ii) the capacity to protect your own interests in
connection with the grant of this option by virtue of the business or financial
expertise of any of your professional advisors who are unaffiliated with and who
are not compensated by the Company or any of its affiliates, directly or
indirectly.


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         8. EXERCISE.

                  (a) This option may be exercised, to the extent specified
above, by delivering a notice of exercise (in a form designated by the Company)
together with the exercise price to the Secretary of the Company, or to such
other person as the Company may designate, during regular business hours,
together with such additional documents as the Company may then require pursuant
to subsection 6(f) of the Plan.

                  (b) By exercising this option you agree that:

                           (i) as a precondition to the completion of any
exercise of this option, the Company may require you to enter an arrangement
providing for the payment by you to the Company of any tax withholding
obligation of the Company arising by reason of (1) the exercise of this option;
(2) the lapse of any substantial risk of forfeiture to which the shares are
subject at the time of exercise; or (3) the disposition of shares acquired upon
such exercise; and

                           (ii) you will notify the Company in writing within
fifteen (15) days after the date of any disposition of any of the shares of the
Common Stock issued upon exercise of this option that occurs within two (2)
years after the date of this option grant or within one (1) year after such
shares of Common Stock are transferred upon exercise of this option.

         9. TRANSFERABILITY. This option is not transferable, except by will or
by the laws of descent and distribution, and is exercisable during your life
only by you. Notwithstanding the foregoing, by delivering written notice to the
Company, in a form satisfactory to the Company, you may designate a third party
who, in the event of your death, shall thereafter be entitled to exercise this
option.

         10. OPTION NOT A SERVICE CONTRACT. This option is not an employment
contract and nothing in this option shall be deemed to create in any way
whatsoever any obligation on your part to continue in the employ of the Company,
or of the Company to continue your employment with the Company. In addition,
nothing in this option shall obligate the Company or any Affiliate of the
Company, or their respective stockholders, Board of Directors, officers or
employees to continue any relationship which you might have as a Director or
Consultant for the Company or Affiliate of the Company.

         11. NOTICES. Any notices provided for in this option or the Plan shall
be given in writing and shall be deemed effectively given upon receipt or, in
the case of notices delivered by the Company to you, five (5) days after deposit
in the United States mail, postage prepaid, addressed to you at the address
specified below or at such other address as you hereafter designate by written
notice to the Company.

         12. GOVERNING PLAN DOCUMENT. This option is subject to all the
provisions of the Plan, a copy of which is attached hereto and its provisions
are hereby made a part of this option, including without limitation the
provisions of Section 6 of the Plan relating to option provisions, and is
further subject to all interpretations, amendments, rules and regulations which
may from time to time be promulgated and adopted pursuant to the Plan. In the
event of any conflict between the provisions of this option and those of the
Plan, the provisions of the Plan shall control.


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         Dated the __________ day of _______________, 19 ___________.

                         Very truly yours,

                         AMERICAN TECHNOLOGY CORPORATION



                         By ___________________________________
                            Duly authorized on behalf
                            of the Board of Directors
ATTACHMENTS:

         American Technology Corporation 1997 Stock Option Plan
         Notice of Exercise


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The undersigned:

                  (a) Acknowledges receipt of the foregoing option and the
attachments referenced therein and understands that all rights and liabilities
with respect to this option are set forth in the option and the Plan; and

                  (b) Acknowledges that as of the date of grant of this option,
it sets forth the entire understanding between the undersigned optionee and the
Company and its Affiliates regarding the acquisition of stock in the Company and
supersedes all prior oral and written agreements on that subject with the
exception of (i) the options previously granted and delivered to the undersigned
under stock option plans of the Company, and (ii) the following agreements only:

         NONE ________________________
                    (Initial)

         OTHER _________________________

                  ____________________________________

                  ____________________________________


                                    ____________________________________
                                    OPTIONEE

                                    Address: ___________________________

                                             ___________________________


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