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                                                                   EXHIBIT 10.37


                            1998 DIRECTOR OPTION PLAN


         1.       PURPOSES OF THE PLAN. The purposes of this 1998 Director
Option Plan are to attract and retain the best available personnel for service
as Outside Directors (as defined herein) of the Company, to provide additional
incentive to the Outside Directors of the Company to serve as Directors and to
encourage their continued service on the Board.

                  All options granted hereunder shall be nonstatutory stock
options.

         2.       DEFINITIONS. As used herein, the following definitions shall
apply:

                  (a)      "BOARD" means the Board of Directors of the Company.

                  (b)      "CODE" means the Internal Revenue Code of 1986, as
amended.

                  (c)      "COMMON STOCK" means the common stock of the Company.

                  (d)      "COMPANY" means Coherent, Inc.

                  (e)      "DIRECTOR" means a member of the Board.

                  (f)      "DISABILITY" means total and permanent disability as
defined in Section 22(e)(3) of the Code.

                  (g)      "EMPLOYEE" means any person, including officers and
Directors, employed by the Company or any Parent or Subsidiary of the Company.
The payment of a Director's fee by the Company shall not be sufficient in and of
itself to constitute "employment" by the Company.

                  (h)      "EXCHANGE ACT" means the Securities Exchange Act of
1934, as amended.

                  (i)      "FAIR MARKET VALUE" means, as of any date, the value
of Common Stock determined as follows:

                           (i)      If the Common Stock is listed on any
established stock exchange or a national market system, including without
limitation the Nasdaq National Market or The Nasdaq SmallCap Market of The
Nasdaq Stock Market, its Fair Market Value shall be the closing sales price for
such stock (or the closing bid, if no sales were reported) as quoted on such
exchange or system for the last market trading day prior to the time of
determination as reported in THE WALL STREET JOURNAL or such other source as the
Administrator deems reliable;

                           (ii)     If the Common Stock is regularly quoted by a
recognized securities dealer but selling prices are not reported, the Fair
Market Value of a Share of Common Stock shall be the mean between the high bid
and low asked prices for the Common Stock for the last market trading day prior
to the time of determination, as reported in THE WALL STREET JOURNAL or such
other source as the Board deems reliable; or

                           (iii)    In the absence of an established market for
the Common Stock, the Fair Market Value thereof shall be determined in good
faith by the Board.

                  (j)      "INSIDE DIRECTOR" means a Director who is an
Employee.

                  (k)      "OPTION" means a stock option granted pursuant to the
Plan.

                  (l)      "OPTIONED STOCK" means the Common Stock subject to an
Option.


                  (m)      "OPTIONEE" means a Director who holds an Option.

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                  (n)      "OUTSIDE DIRECTOR" means a Director who is not an
Employee.

                  (o)      "PARENT" means a "parent corporation," whether now or
hereafter existing, as defined in Section 424(e) of the Code.

                  (p)      "PLAN" means this 1998 Director Option Plan.

                  (q)      "SHARE" means a share of the Common Stock, as
adjusted in accordance with Section 10 of the Plan.

                  (r)      "SUBSIDIARY" means a "subsidiary corporation,"
whether now or hereafter existing, as defined in Section 424(f) of the Internal
Revenue Code of 1986.

         3.       STOCK SUBJECT TO THE PLAN. Subject to the provisions of
Section 10 of the Plan, the maximum aggregate number of Shares that may be
optioned and sold under the Plan is 100,000 Shares (the "POOL") (the Shares may
be authorized, but unissued, or reacquired Common Stock), plus an annual
increase to be added on each anniversary date of the adoption of the Plan equal
to (i) the number of Shares needed to restore the maximum aggregate number of
Shares that may be optioned and sold under the Plan to 100,000 or (ii) a lesser
amount determined by the Board of Directors.

                  If an Option expires or becomes unexercisable without having
been exercised in full, the unpurchased Shares which were subject thereto shall
become available for future grant or sale under the Plan (unless the Plan has
terminated). Shares that have actually been issued under the Plan shall not be
returned to the Plan and shall not become available for future distribution
under the Plan.

         4.       ADMINISTRATION AND GRANTS OF OPTIONS UNDER THE PLAN.

                  (a)      PROCEDURE FOR GRANTS. All grants of Options to
Outside Directors under this Plan shall be automatic and nondiscretionary and
shall be made strictly in accordance with the following provisions:

                           (i)      No person shall have any discretion to
select which Outside Directors shall be granted Options or to determine the
number of Shares to be covered by Options.

                           (ii)     Each Outside Director shall be automatically
granted an Option to purchase 20,000 Shares (the "FIRST OPTION") on the date on
which such person first becomes an Outside Director, whether through election by
the stockholders of the Company or appointment by the Board to fill a vacancy;
PROVIDED, HOWEVER, that an Inside Director who ceases to be an Inside Director
but who remains a Director shall not receive a First Option.

                           (iii)    Each Outside Director shall be automatically
granted an Option to purchase 5,000 Shares (a "SUBSEQUENT OPTION") immediately
following each annual meeting of stockholders at which such Outside Director is
re-elected (beginning with the 2000 annual meeting of stockholders) provided he
or she is then an Outside Director and if as of such date, he or she shall have
served on the Board for at least the preceding three (3) months.

                           (iv)     Notwithstanding the provisions of
subsections (ii) and (iii) hereof, any exercise of an Option granted before the
Company has obtained stockholder approval of the Plan in accordance with Section
16 hereof shall be conditioned upon obtaining such stockholder approval of the
Plan in accordance with Section 16 hereof.

                           (v)      The terms of an Option granted hereunder
shall be as follows:

                                    (A)     the term of the Option shall be six
(6) years.

                                    (B)     the Option shall be exercisable only
while the Outside Director remains a Director of the Company, except as set
forth in Sections 8 and 10 hereof.

                                    (C)     the exercise price per Share shall
be 100% of the Fair Market Value per Share on the date of grant of the First
Option.

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                                    (D)     subject to Section 10 hereof, the
First Option shall become exercisable cumulatively to the extent of twenty-five
percent (25%) of the Shares subject to such option on each of the first four
anniversaries of the date of grant, provided that the Optionee continues to
serve as a Director on such dates.

                                    (E)     subject to Section 10 hereof, each
Subsequent Option shall become exercisable with respect to 100% of the Shares
subject to such option on the fourth anniversary of the date of grant, provided
that the Optionee continues to serve as a Director on such date.

                           (vi)     In the event that any Option granted under
the Plan would cause the number of Shares subject to outstanding Options plus
the number of Shares previously purchased under Options to exceed the Pool, then
the remaining Shares available for Option grant shall be granted under Options
to the Outside Directors on a pro rata basis. No further grants shall be made
until such time, if any, as additional Shares become available for grant under
the Plan through action of the Board or the stockholders to increase the number
of Shares that may be issued under the Plan or through cancellation or
expiration of Options previously granted hereunder.

                  (b)      SUSPENSION OR TERMINATION OF OPTION. If the Chief
Executive Officer or his designee reasonably believes that an Optionee has
committed an act of misconduct, the Chief Executive Officer may suspend the
Optionee's right to exercise any option pending a determination by the Board of
Directors (excluding the Outside Director accused of such misconduct). If the
Board of Directors (excluding the Outside Director accused of such misconduct)
determines an Optionee has committed an act of embezzlement, fraud, dishonesty,
nonpayment of an obligation owed to the Company, breach of fiduciary duty or
deliberate disregard of the Company rules resulting in loss, damage or injury to
the Company, or if an Optionee makes an unauthorized disclosure of any Company
trade secret or confidential information, engages in any conduct constituting
unfair competition, induces any Company customer to breach a contract with the
Company or induces any principal for whom the Company acts as agent to terminate
such agency relationship, neither the Optionee nor his estate shall be entitled
to exercise any option whatsoever. In making such determination, the Board of
Directors (excluding the Outside Director accused of such misconduct) shall act
fairly and shall give the Optionee an opportunity to appear and present evidence
on Optionee's behalf at a hearing before the Board or a committee of the Board.

         5.       ELIGIBILITY. Options may be granted only to Outside
Directors. All Options shall be automatically granted in accordance with the
terms set forth in Section 4 hereof.

                  The Plan shall not confer upon any Optionee any right with
respect to continuation of service as a Director or nomination to serve as a
Director, nor shall it interfere in any way with any rights which the Director
or the Company may have to terminate the Director's relationship with the
Company at any time.

         6.       TERM OF PLAN. The Plan shall become effective upon the earlier
to occur of its adoption by the Board or its approval by the stockholders of the
Company as described in Section 16 of the Plan. It shall continue in effect for
a term of ten (10) years unless sooner terminated under Section 11 of the Plan.

         7.       FORM OF CONSIDERATION. The consideration to be paid for the
Shares to be issued upon exercise of an Option, including the method of payment,
shall consist of (i) cash, (ii) check, (iii) other shares which (x) in the case
of Shares acquired upon exercise of an option, have been owned by the Optionee
for more than six (6) months on the date of surrender, and (y) have a Fair
Market Value on the date of surrender equal to the aggregate exercise price of
the Shares as to which said Option shall be exercised, (iv) consideration
received by the Company under a cashless exercise program (if any) implemented
by the Company in connection with the Plan, or (v) any combination of the
foregoing methods of payment.

         8.       EXERCISE OF OPTION.

                  (a)      PROCEDURE FOR EXERCISE; RIGHTS AS A STOCKHOLDER. Any
Option granted hereunder shall be exercisable at such times as are set forth in
Section 4 hereof; PROVIDED, HOWEVER, that no Options shall be exercisable until
stockholder approval of the Plan in accordance with Section 16 hereof has been
obtained.

                  An Option may not be exercised for a fraction of a Share.

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                  An Option shall be deemed to be exercised when written notice
of such exercise has been given to the Company in accordance with the terms of
the Option by the person entitled to exercise the Option and full payment for
the Shares with respect to which the Option is exercised has been received by
the Company. Full payment may consist of any consideration and method of payment
allowable under Section 7 of the Plan. Until the issuance (as evidenced by the
appropriate entry on the books of the Company or of a duly authorized transfer
agent of the Company) of the stock certificate evidencing such Shares, no right
to vote or receive dividends or any other rights as a stockholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
A share certificate for the number of Shares so acquired shall be issued to the
Optionee as soon as practicable after exercise of the Option. No adjustment
shall be made for a dividend or other right for which the record date is prior
to the date the stock certificate is issued, except as provided in Section 10 of
the Plan.

                  Exercise of an Option in any manner shall result in a decrease
in the number of Shares which thereafter may be available, both for purposes of
the Plan and for sale under the Option, by the number of Shares as to which the
Option is exercised.

                  (b)      TERMINATION OF CONTINUOUS STATUS AS A DIRECTOR.
Subject to Section 10 hereof, in the event an Optionee's status as a Director
terminates (other than upon the Optionee's death or Disability), the Optionee
may exercise his or her Option, but only within 210 days following the date of
such termination, and only to the extent that the Optionee was entitled to
exercise it on the date of such termination (but in no event later than the
expiration of its six (6) year term). To the extent that the Optionee was not
entitled to exercise an Option on the date of such termination, and to the
extent that the Optionee does not exercise such Option (to the extent otherwise
so entitled) within the time specified herein, the Option shall terminate.

                  (c)      DISABILITY OF OPTIONEE. In the event Optionee's
status as a Director terminates as a result of Disability, the Optionee may
exercise his or her Option, but only within twelve (12) months following the
date of such termination, and only to the extent that the Optionee would have
been entitled to exercise the Option had the Optionee not been disabled and
remained an Outside Director for six (6) months after such termination (but in
no event later than the expiration of its six (6) year term). To the extent that
the Optionee would not have been entitled to exercise an Option had the Optionee
not been disabled and remained an Outside Director for six (6) months after such
termination, or if he or she does not exercise such Option (to the extent
otherwise so entitled) within the time specified herein, the Option shall
terminate.

                  (d)      DEATH OF OPTIONEE. In the event of an Optionee's
death, the Optionee's estate or a person who acquired the right to exercise the
Option by bequest or inheritance may exercise the Option, but only within twelve
(12) months following the date of death, and only to the extent that the
Optionee would have been entitled to exercise the Option had the Optionee
continued living and remained an Outside Director for six (6) months after the
date of death (but in no event later than the expiration of its six (6) year
term). To the extent that the Optionee would not have been entitled to exercise
an Option had the Optionee continued living and remained an Outside Director for
six (6) months after the date of death, and to the extent that the Optionee's
estate or a person who acquired the right to exercise such Option does not
exercise such Option (to the extent otherwise so entitled) within the time
specified herein, the Option shall terminate.

         9.       NON-TRANSFERABILITY OF OPTIONS. The Option may not be sold,
pledged, assigned, hypothecated, transferred, or disposed of in any manner other
than by will or by the laws of descent or distribution and may be exercised,
during the lifetime of the Optionee, only by the Optionee.

         10.      ADJUSTMENTS UPON CHANGES IN CAPITALIZATION, DISSOLUTION,
MERGER OR ASSET SALE.

                  (a)      CHANGES IN CAPITALIZATION. Subject to any required
action by the stockholders of the Company, the number of Shares covered by each
outstanding Option, the number of Shares which have been authorized for issuance
under the Plan but as to which no Options have yet been granted or which have
been returned to the Plan upon cancellation or expiration of an Option, as well
as the price per Share covered by each such outstanding Option, and the number
of Shares issuable pursuant to the automatic grant provisions of Section 4
hereof shall be proportionately adjusted for any increase or decrease in the
number of issued Shares resulting from a stock split, reverse stock split, stock
dividend, combination or reclassification of the Common Stock, or any other
increase or decrease in the number of issued Shares effected without receipt of
consideration by the Company; PROVIDED, HOWEVER, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected

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without receipt of consideration." Except as expressly provided herein, no
issuance by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall affect, and no adjustment
by reason thereof shall be made with respect to, the number or price of Shares
subject to an Option.

                  (b)      DISSOLUTION OR LIQUIDATION. In the event of the
proposed dissolution or liquidation of the Company, to the extent that an Option
has not been previously exercised, it shall terminate immediately prior to the
consummation of such proposed action.

                  (c)      MERGER OR ASSET SALE. In the event of a proposed
merger of the Company with or into another corporation where following such
merger the stockholders of the Company prior to such merger own less than 50% of
the voting securities of the surviving corporation (a "change of control"), or
the sale of all or substantially all of the assets of the Company, each
outstanding Option shall be assumed or an equivalent option shall be substituted
by such successor corporation or a parent or subsidiary of such successor
corporation. If an Option is assumed or substituted for, the Option or
equivalent option shall continue to be exercisable as provided in Section 4
hereof for so long as the Optionee serves as a Director or a director of the
successor corporation. Following such assumption or substitution, if the
Optionee's status as a Director or director of the successor corporation, as
applicable, is terminated other than upon a voluntary resignation by the
Optionee, the Option or option shall become fully exercisable, including as to
Shares for which it would not otherwise be exercisable. Thereafter, the Option
or option shall remain exercisable in accordance with Section 8 above. In the
event that such successor corporation refuses to assume the Option or to
substitute an equivalent option, the Board shall, in lieu of such assumption or
substitution, provide for the Optionee to have the right to exercise the Option
as to all of the Optioned Stock, including Shares as to which the Option would
not otherwise be exercisable. If an Option becomes fully exercisable in lieu of
assumption or substitution in the event of a merger or sale of assets, the Board
shall notify the Optionee that the Option shall be fully exercisable for a
period of twenty (20) days from the date of such notice, and the Option will
terminate upon the expiration of such period.

         For the purposes of this Section 10(c), an Option shall be considered
assumed if, following the merger or sale of assets, the Option confers the right
to purchase or receive, for each Share of Optioned Stock subject to the Option
immediately prior to the merger or sale of assets, the consideration (whether
stock, cash, or other securities or property) received in the merger or sale of
assets by holders of Common Stock for each Share held on the effective date of
the transaction (and if holders were offered a choice of consideration, the type
of consideration chosen by the holders of a majority of the outstanding Shares).
If such consideration received in the merger or sale of assets is not solely
common stock of the successor corporation or its Parent, the Board may, with the
consent of the successor corporation, provide for the consideration to be
received upon the exercise of the Option, for each Share of Optioned Stock
subject to the Option, to be solely common stock of the successor corporation or
its Parent equal in fair market value to the per share consideration received by
holders of Common Stock in the merger or sale of assets.

         11.      AMENDMENT AND TERMINATION OF THE PLAN.

                  (a)      AMENDMENT AND TERMINATION. The Board may at any time
amend, alter, suspend, or discontinue the Plan, but no amendment, alteration,
suspension, or discontinuation shall be made that would impair the rights of any
Optionee under any grant theretofore made, without his or her consent. In
addition, to the extent necessary and desirable to comply with any applicable
law, regulation or stock exchange rule, the Company shall obtain stockholder
approval of any Plan amendment in such a manner and to such a degree as
required.

                  (b)      EFFECT OF AMENDMENT OR TERMINATION. Any such
amendment or termination of the Plan shall not affect Options already granted
and such Options shall remain in full force and effect as if this Plan had not
been amended or terminated.

         12.      TIME OF GRANTING OPTIONS. The date of grant of an Option
shall, for all purposes, be the date determined in accordance with Section 4
hereof.

         13.      CONDITIONS UPON ISSUANCE OF SHARES. Shares shall not be issued
pursuant to the exercise of an Option unless the exercise of such Option and the
issuance and delivery of such Shares pursuant thereto shall comply with all
relevant provisions of law, including, without limitation, the Securities Act of
1933, as amended, the Exchange Act, the rules and regulations promulgated
thereunder, state securities laws, and the requirements of any stock exchange
upon which the Shares may then be listed, and shall be further subject to the
approval of counsel for the Company with respect to such compliance.

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                  As a condition to the exercise of an Option, the Company may
require the person exercising such Option to represent and warrant at the time
of any such exercise that the Shares are being purchased only for investment and
without any present intention to sell or distribute such Shares, if, in the
opinion of counsel for the Company, such a representation is required by any of
the aforementioned relevant provisions of law.

                  Inability of the Company to obtain authority from any
regulatory body having jurisdiction, which authority is deemed by the Company's
counsel to be necessary to the lawful issuance and sale of any Shares hereunder,
shall relieve the Company of any liability in respect of the failure to issue or
sell such Shares as to which such requisite authority shall not have been
obtained.

         14.      RESERVATION OF SHARES. The Company, during the term of this
Plan, will at all times reserve and keep available such number of Shares as
shall be sufficient to satisfy the requirements of the Plan.

         15.      OPTION AGREEMENT. Options shall be evidenced by written option
agreements in such form as the Board shall approve.

         16.      STOCKHOLDER APPROVAL. The Plan shall be subject to approval by
the stockholders of the Company within twelve (12) months after the date the
Plan is adopted. Such stockholder approval shall be obtained in the degree and
manner required under applicable state and federal law and any stock exchange
rules.


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