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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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Amendment No. 1
to
SCHEDULE TO

Tender Offer Statement Under Section 14(d)(1) or 13(e)(1)
of the Securities Exchange Act of 1934

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COHERENT, INC.
(Name of Subject Company (Issuer) and Name of Filing Person (Offeror))

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Common stock, Par Value $0.01 Per Share
(Title of Class of Securities)

192479103
(CUSIP Number of Class of Securities)

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Bret DiMarco
Executive Vice President and General Counsel
5100 Patrick Henry Drive
Santa Clara, CA 95054
(408) 764-4000
(Name, address and telephone number of person authorized to receive notices
and communication on behalf of Filing Persons)

Copy to:
John A. Fore
Michael A. Occhiolini
Wilson Sonsini Goodrich & Rosati
Professional Corporation
650 Page Mill Road
Palo Alto, CA 94304
(650) 493-9300

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CALCULATION OF REGISTRATION FEE

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Check the box if any part of the filing fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

o

Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transaction to which the statement relates:

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third party tender offer subject to Rule 14d-1.



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issuer tender offer subject to Rule 13e-4.



o

going private transaction subject to Rule 13e-3.



o

amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

o

Rule 13e-4(i) (Cross-Border Issuer Tender Offer)



o

Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)

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INTRODUCTION

        Coherent, Inc., a Delaware corporation ("Coherent" or the "Company"), hereby amends and supplements the Tender Offer Statement on Schedule TO originally filed with the Securities and Exchange Commission on February 10, 2011 (the "Schedule TO"). The Schedule TO relates to the Company's offer to purchase up to 1,271,000 shares of its common stock, par value $0.01 per share, at a price not greater than $59.00 nor less than $53.00 per share, net to the seller in cash, less any applicable withholding taxes and without interest, upon the terms and subject to the conditions set forth in the Offer to Purchase dated February 10, 2011 (the "Offer to Purchase"), previously filed as Exhibit (a)(1)(A) to the Schedule TO, and in the related Letter of Transmittal (the "Letter of Transmittal"), previously filed as Exhibit (a)(1)(B) to the Schedule TO (which, as amended or supplemented from time to time, together constitute the "Offer"). The Offer expired at 5:00 p.m., New York City Time, on Friday, March 11, 2011. This Amendment No. 1, as it amends and supplements the Schedule TO, is intended to satisfy the reporting requirements of Rule 13e-4(c)(3) of the Securities Exchange Act of 1934, as amended.

        Only those items amended are reported in this Amendment No. 1. Except as specifically provided herein, the information contained in the Schedule TO remains unchanged and this Amendment No. 1 does not modify any of the information previously reported on Schedule TO.

Item 4.    Terms of the Transaction.

        Item 4 of the Schedule TO is hereby amended and supplemented by inserting at the end thereof the following:

        The tender offer expired at 5:00 p.m., New York City time, on Friday, March 11, 2011. Based on a preliminary count, we have been advised by the depositary that 457,028 shares of our common stock (including 261,111 shares of common stock delivered pursuant to guaranteed deliveries), or approximately 1.8% of the total outstanding shares of common stock, were validly tendered and not withdrawn in the tender offer at or below a price of $59.00. In accordance with the terms of the tender offer, we have accepted all of the validly tendered shares at a purchase price per share of $59.00. On March 14, 2011, we issued a press release announcing the preliminary results of the tender offer. A copy of this press release is filed as Exhibit (a)(1)(I) to the Schedule TO and is incorporated herein by reference.

Item 12.    Exhibits.

1

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2

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SIGNATURE

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

3

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Exhibit Index

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INTRODUCTION

Item 4. Terms of the Transaction .
Item 12. Exhibits .

SIGNATURE
Exhibit Index