Exhibit 5.1


                       [LETTERHEAD OF GREGORY A. ROBBINS]


                                                               November 7, 2000


Veeco Instruments Inc.
Terminal Drive
Plainview, New York 11803

Ladies and Gentlemen:

I am Vice President and General Counsel of Veeco Instruments Inc., a Delaware
corporation (the "Company"), and in such capacity I have acted as counsel to the
Company in connection with the Registration Statement on Form S-8 (the
"Registration Statement") filed by the Company with the Securities and Exchange
Commission pursuant to the Securities Act of 1933, as amended (the "Act"), and
the rules and regulations promulgated thereunder (the "Rules"). The Registration
Statement covers 150,000 shares (the "Shares"), par value $0.01 per share of
common stock ("Common Stock") of the Company to be issued pursuant to the
Company's 2000 Stock Option Plan for Non-Officer Employees (the "Plan").

In that connection, I have reviewed the Company's certificate of incorporation,
its bylaws, resolutions of its board of directors, the Registration Statement,
the Plan and such other documents as I have deemed appropriate. On the basis of
such review, and having regard to legal considerations I deem relevant, I am of
the opinion that the Shares have been duly authorized for issuance and that the
Shares, when issued and delivered by the Company and paid for in accordance with
the terms and provisions of the Plan, will be validly issued, fully paid and
nonassessable.

I am admitted to practice law in the State of New York and, as such, the opinion
set forth above is based as to matters of law solely on applicable provisions of
the General Corporation Law of the State of Delaware and I express no opinion as
to any other laws, statutes, ordinanances, rules or regulations. I hereby
consent to the filing of this opinion as an exhibit to the Registration
Statement. In giving this consent, I do not thereby admit that I am in the
category of persons whose consent is required by the Act or the Rules.

Sincerely,

/s/ Gregory A. Robbins

Gregory A. Robbins
Vice President and General Counsel