<Page>
EXHIBIT 10.18
BOOKHAM, INC.
2004 EMPLOYEE STOCK PURCHASE PLAN
September 10, 2004
The purpose of this Plan is to provide eligible employees of Bookham, Inc. (the
"Company") and certain of its subsidiaries with opportunities to purchase shares
of the Company's common stock, $.01 par value (the "Common Stock"), commencing
on January 1, 2005. Five Hundred Thousand (500,000) shares of Common Stock in
the aggregate have been approved for this purpose. This Plan is intended to
qualify as an "employee stock purchase plan" as defined in Section 423 of the
Internal Revenue Code of 1986, as amended (the "Code"), and the regulations
promulgated thereunder, and shall be interpreted consistent therewith.
1. ADMINISTRATION. The Plan will be administered by the Company's Board
of Directors (the "Board") or by a Committee appointed by the Board (the
"Committee"). The Board or the Committee has authority to make rules and
regulations for the administration of the Plan and its interpretation and
decisions with regard thereto shall be final and conclusive.
2. ELIGIBILITY. All employees of the Company, including Directors who are
employees, and all employees of any subsidiary of the Company (as defined in
Section 424(f) of the Code) designated by the Board or the Committee from time
to time (a "Designated Subsidiary"), are eligible to participate in any one or
more of the offerings of Options (as defined in Section 9) to purchase Common
Stock under the Plan provided that:
(a) they are customarily employed by the Company or a
Designated Subsidiary for more than 20 hours a week and for more than five
months in a calendar year; and
(b) they have been employed by the Company or a Designated
Subsidiary for at least six (6) months prior to enrolling in the Plan; and
(c) they are employees of the Company or a Designated
Subsidiary on the first day of the applicable Plan Period (as defined
below).
No employee may be granted an option hereunder if such employee,
immediately after the option is granted, owns 5% or more of the total combined
voting power or value of the stock of the Company or any subsidiary. For
purposes of the preceding sentence, the attribution rules of Section 424(d) of
the Code shall apply in determining the stock ownership of an employee, and all
stock which the employee has a contractual right to purchase shall be treated as
stock owned by the employee.
3. OFFERINGS. The Company will make one or more offerings ("Offerings")
to employees to purchase stock under this Plan. Offerings will begin each
January 1 and July 1, or the first business day thereafter (the "Offering
Commencement Dates"). Each Offering Commencement Date will begin a six (6) month
period (a "Plan Period") during which payroll deductions will be made and held
for the purchase of Common Stock at the end of the Plan
<Page>
Period. The Board or the Committee may, at its discretion, choose a different
Plan Period of twelve (12) months or less for subsequent Offerings.
4. PARTICIPATION. An employee eligible on the Offering Commencement Date
of any Offering may participate in such Offering by completing and forwarding a
payroll deduction authorization form to the employee's appropriate payroll
office at least 10 days prior to the applicable Offering Commencement Date. The
form will authorize a regular payroll deduction from the Compensation received
by the employee during the Plan Period. Unless an employee files a new form or
withdraws from the Plan, his deductions and purchases will continue at the same
rate for future Offerings under the Plan as long as the Plan remains in effect.
The term "Compensation" means the amount of money reportable on the employee's
Federal Income Tax Withholding Statement, excluding overtime, shift premium,
incentive or bonus awards, allowances and reimbursements for expenses such as
relocation allowances for travel expenses, income or gains on the exercise of
Company stock options or stock appreciation rights, and similar items, whether
or not shown on the employee's Federal Income Tax Withholding Statement, but
including, in the case of salespersons, sales commissions to the extent
determined by the Board or the Committee.
5. DEDUCTIONS. The Company will maintain payroll deduction accounts for
all participating employees. With respect to any Offering made under this Plan,
an employee may authorize a payroll deduction in any dollar amount up to a
maximum of 15% of the Compensation he or she receives during the Plan Period or
such shorter period during which deductions from payroll are made. The minimum
payroll deduction is such percentage of compensation as may be established from
time to time by the Board or the Committee.
6. DEDUCTION CHANGES. An employee may decrease or discontinue his payroll
deduction once during any Plan Period, by filing a new payroll deduction
authorization form. However, an employee may not increase his payroll deduction
during a Plan Period. If an employee elects to discontinue his payroll
deductions during a Plan Period, but does not elect to withdraw his funds
pursuant to Section 8 hereof, funds deducted prior to his election to
discontinue will be applied to the purchase of Common Stock on the Exercise Date
(as defined below).
7. INTEREST. Interest will not be paid on any employee accounts, except
to the extent that the Board or the Committee, in its sole discretion, elects to
credit employee accounts with interest at such per annum rate as it may from
time to time determine.
8. WITHDRAWAL OF FUNDS. An employee may at any time prior to the close of
business on the last business day in a Plan Period and for any reason
permanently draw out the balance accumulated in the employee's account and
thereby withdraw from participation in an Offering. Partial withdrawals are not
permitted. The employee may not begin participation again during the remainder
of the Plan Period. The employee may participate in any subsequent Offering in
accordance with terms and conditions established by the Board or the Committee.
9. PURCHASE OF SHARES. On the Offering Commencement Date of each Plan
Period, the Company will grant to each eligible employee who is then a
participant in the Plan an option ("Option") to purchase on the last business
day of such Plan Period (the "Exercise Date"), at the
- 2 -
<Page>
Option Price hereinafter provided for, the largest number of whole shares of
Common Stock of the Company as does not exceed the number of shares determined
by multiplying $2,083 by the number of full months in the Offering Period and
dividing the result by the closing price (as defined below) on the Offering
Commencement Date of such Plan Period.
Notwithstanding the above, no employee may be granted an Option which
permits his rights to purchase Common Stock under this Plan and any other
employee stock purchase plan (as defined in Section 423(b) of the Code) of the
Company and its subsidiaries, to accrue at a rate which exceeds $25,000 of the
fair market value of such Common Stock (determined at the Offering Commencement
Date of the Plan Period) for each calendar year in which the Option is
outstanding at any time.
The purchase price for each share purchased will be 85% of the closing
price of the Common Stock on (i) the first business day of such Plan Period or
(ii) the Exercise Date, whichever closing price shall be less. Such closing
price shall be (a) the closing price on any national securities exchange on
which the Common Stock is listed, (b) the closing price of the Common Stock on
the Nasdaq National Market or (c) the average of the closing bid and asked
prices in the over-the-counter-market, whichever is applicable, as published in
THE WALL STREET JOURNAL. If no sales of Common Stock were made on such a day,
the price of the Common Stock for purposes of clauses (a) and (b) above shall be
the reported price for the next preceding day on which sales were made.
Each employee who continues to be a participant in the Plan on the Exercise
Date shall be deemed to have exercised his Option at the Option Price on such
date and shall be deemed to have purchased from the Company the number of full
shares of Common Stock reserved for the purpose of the Plan that his accumulated
payroll deductions on such date will pay for, but not in excess of the maximum
number determined in the manner set forth above.
Any balance remaining in an employee's payroll deduction account at the end
of a Plan Period will be automatically refunded to the employee, except that any
balance which is less than the purchase price of one share of Common Stock will
be carried forward into the employee's payroll deduction account for the
following Offering, unless the employee elects not to participate in the
following Offering under the Plan, in which case the balance in the employee's
account shall be refunded.
10. ISSUANCE OF CERTIFICATES. Certificates representing shares of Common
Stock purchased under the Plan may be issued only in the name of the employee,
in the name of the employee and another person of legal age as joint tenants
with rights of survivorship, or (in the Company's sole discretion) in the name
of a brokerage firm, bank or other nominee holder designated by the employee.
The Company may, in its sole discretion and in compliance with applicable laws,
authorize the use of book entry registration of shares in lieu of issuing stock
certificates.
11. RIGHTS ON RETIREMENT, DEATH OR TERMINATION OF EMPLOYMENT. In the event
of a participating employee's termination of employment prior to the last
business day of a Plan Period, no payroll deduction shall be taken from any pay
due and owing to an employee and the balance in the employee's account shall be
paid to the employee or, in the event of the
- 3 -
<Page>
employee's death, (a) to a beneficiary previously designated in a revocable
notice signed by the employee (with any spousal consent required under state
law) or (b) in the absence of such a designated beneficiary, to the executor or
administrator of the employee's estate or (c) if no such executor or
administrator has been appointed to the knowledge of the Company, to such other
person(s) as the Company may, in its discretion, designate. If, prior to the
last business day of the Plan Period, the Designated Subsidiary by which an
employee is employed shall cease to be a subsidiary of the Company, or if the
employee is transferred to a subsidiary of the Company that is not a Designated
Subsidiary, the employee shall be deemed to have terminated employment for the
purposes of this Plan.
12. OPTIONEES NOT STOCKHOLDERS. Neither the granting of an Option to an
employee nor the deductions from his pay shall constitute such employee a
stockholder of the shares of Common Stock covered by an Option under this Plan
until such shares have been purchased by and issued to him.
13. RIGHTS NOT TRANSFERABLE. Rights under this Plan are not transferable
by a participating employee other than by will or the laws of descent and
distribution, and are exercisable during the employee's lifetime only by the
employee.
14. APPLICATION OF FUNDS. All funds received or held by the Company under
this Plan may be combined with other corporate funds and may be used for any
corporate purpose.
15. ADJUSTMENT IN CASE OF CHANGES AFFECTING COMMON STOCK. In the event of
a subdivision of outstanding shares of Common Stock, or the payment of a
dividend in Common Stock, the number of shares approved for this Plan, and the
share limitation set forth in Section 9, shall be increased proportionately, and
such other adjustment shall be made as may be deemed equitable by the Board or
the Committee. In the event of any other change affecting the Common Stock, such
adjustment shall be made as may be deemed equitable by the Board or the
Committee to give proper effect to such event.
16. MERGER. If the Company shall at any time merge or consolidate with
another corporation or undertake a share exchange transaction with another
corporation and the holders of the capital stock of the Company immediately
prior to such merger or consolidation continue to hold at least 80% by voting
power of the capital stock of the surviving corporation ("Continuity of
Control"), the holder of each Option then outstanding will thereafter be
entitled to receive at the next Exercise Date upon the exercise of such Option
for each share as to which such Option shall be exercised the securities or
property which a holder of one share of the Common Stock was entitled to upon
and at the time of such merger or consolidation, and the Board or the Committee
shall take such steps in connection with such merger or consolidation as the
Board or the Committee shall deem necessary to assure that the provisions of
Section 15 shall thereafter be applicable, as nearly as reasonably may be, in
relation to the said securities or property as to which such holder of such
Option might thereafter be entitled to receive thereunder.
In the event of a merger or consolidation of the Company with or into
another corporation or a share exchange transaction with another corporation
which does not involve Continuity of Control, or of a sale of all or
substantially all of the assets of the Company while
- 4 -
<Page>
unexercised Options remain outstanding under the Plan, (a) subject to the
provisions of clauses (b) and (c), after the effective date of such transaction,
each holder of an outstanding Option shall be entitled, upon exercise of such
Option, to receive in lieu of shares of Common Stock, shares of such stock or
other securities as the holders of shares of Common Stock received pursuant to
the terms of such transaction; or (b) all outstanding Options may be cancelled
by the Board or the Committee as of a date prior to the effective date of any
such transaction and all payroll deductions shall be paid out to the
participating employees; or (c) all outstanding Options may be cancelled by the
Board or the Committee as of the effective date of any such transaction,
provided that notice of such cancellation shall be given to each holder of an
Option, and each holder of an Option shall have the right to exercise such
Option in full based on payroll deductions then credited to his account as of a
date determined by the Board or the Committee, which date shall not be less than
ten (10) days preceding the effective date of such transaction.
17. AMENDMENT OF THE PLAN. The Board may at any time, and from time to
time, amend this Plan in any respect, except that (a) if the approval of any
such amendment by the shareholders of the Company is required by Section 423 of
the Code, such amendment shall not be effected without such approval, and (b) in
no event may any amendment be made which would cause the Plan to fail to comply
with Section 423 of the Code.
18. INSUFFICIENT SHARES. In the event that the total number of shares of
Common Stock specified in elections to be purchased under any Offering plus the
number of shares purchased under previous Offerings under this Plan exceeds the
maximum number of shares issuable under this Plan, the Board or the Committee
will allot the shares then available on a pro rata basis.
19. TERMINATION OF THE PLAN. This Plan may be terminated at any time by
the Board. Upon termination of this Plan all amounts in the accounts of
participating employees shall be promptly refunded.
20. GOVERNMENTAL REGULATIONS. The Company's obligation to sell and deliver
Common Stock under this Plan is subject to listing on a national stock exchange
or quotation on the Nasdaq National Market (to the extent the Common Stock is
then so listed or quoted) and the approval of all governmental authorities
required in connection with the authorization, issuance or sale of such stock.
21. GOVERNING LAW. The Plan shall be governed by Delaware law except to
the extent that such law is preempted by federal law.
22. ISSUANCE OF SHARES. Shares may be issued upon exercise of an Option
from authorized but unissued Common Stock, from shares held in the treasury of
the Company, or from any other proper source.
23. NOTIFICATION UPON SALE OF SHARES. Each employee agrees, by entering
the Plan, to promptly give the Company notice of any disposition of shares
purchased under the Plan where such disposition occurs within two years after
the date of grant of the Option pursuant to which such shares were purchased.
24. WITHHOLDING. Each employee shall, no later than the date of the event
creating the tax liability, make provision satisfactory to the Board for payment
of any taxes required by law
- 5 -
<Page>
to be withheld in connection with any transaction related to Options granted to
or shares acquired by such employee pursuant to the Plan. The Company may, to
the extent permitted by law, deduct any such taxes from any payment of any kind
otherwise due to an employee.
25. EFFECTIVE DATE AND APPROVAL OF SHAREHOLDERS. The Plan shall take
effect on September 10, 2004 subject to approval by the shareholders of the
Company as required by Section 423 of the Code, which approval must occur within
twelve months of the adoption of the Plan by the Board.
Adopted by the Board of Directors
on September 9, 2004
Approved by the stockholders on
September 9, 2004
- 6 -