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                                                                     EXHIBIT 5.1

                      [MORRISON & FOERSTER LLP LETTERHEAD]

                                December __, 2003

JDS Uniphase Corporation
1768 Automation Parkway
San Jose, California  95131

Ladies and Gentlemen:

At your request, we have examined the registration statement on Form S-3 filed
by JDS Uniphase Corporation, a Delaware corporation (the "Company"), with the
Securities and Exchange Commission on November 14, 2003 (the "Registration
Statement"), relating to the registration under the Securities Act of 1933, as
amended, of the resale by the holders thereof of $475,000,000 aggregate
principal amount of Zero Coupon Senior Convertible Notes due 2010 (the "Notes")
and the shares of the Company's common stock, $0.001 par value per share (the
"Conversion Shares") issuable upon conversion of the Notes (the Conversion
Shares together with the Notes, the "Securities"). The Notes were issued
pursuant to an Indenture dated as of October 31, 2003 ("Indenture") by and
between the Company and The Bank of New York, as Trustee. The Securities are
being offered by certain selling securityholders specified in the Registration
Statement.

In connection with this opinion, (i) we have reviewed the Registration
Statement, the Indenture, the Notes and certain of the Company's other corporate
records, documents, instruments and proceedings taken in connection with the
authorization and issuance of the Notes and the Conversion Shares, and (ii) we
have made such inquiries of officers of the Company and public officials and
have considered such questions of law as we have deemed necessary for the
purpose of rendering the opinions set forth herein.

We have assumed the genuineness of all signatures on and the authenticity of all
items submitted to us as originals and the conformity to originals of all items
submitted to us as copies. We also have relied, as to matters of fact, upon the
accuracy of representations and certificates of the Company's officers. We have
also relied on the Company's records and have assumed the accuracy and
completeness thereof. In making our examination of executed documents or
documents to be executed, we have assumed that the parties thereto, other than
the Company, had or will have the power, corporate or other, to enter into and
perform all obligations thereunder and have also assumed the due authorization
by all requisite action, corporate or other, and execution and delivery by such
parties of such documents and the validity and binding effect thereof on such
parties. The opinions hereinafter expressed are subject to the effect of
bankruptcy, insolvency, reorganization, arrangement, moratorium or other similar
laws relating to or affecting the rights of creditors generally, including,
without limitation, laws relating to fraudulent transfers or conveyances,
preferences and equitable subordination; limitations imposed by general
principles of equity upon the availability of equitable remedies or the
enforcement of provisions of the Notes and the Indenture; and the effect of
judicial decisions which have held that certain provisions are unenforceable
where their enforcement would violate the implied covenant of good faith and
fair dealing, or would be commercially unreasonable, or where their breach is
not material. In rendering the opinion in Paragraph 1 below, we have also
assumed that the global notes representing the Notes was duly authenticated by
the Trustee.

Based upon and subject to the foregoing, we are of the opinion that:

1. The Notes have been duly authorized and are valid and binding obligations of
the Company.

2. When issued upon conversion in accordance with the terms of the Notes and the
Indenture, the Conversion Shares will be validly issued, fully paid and
nonassessable.
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The opinions expressed herein are limited to the federal laws of the United
States of America, the General Corporation Law of the State of Delaware and the
laws of the State of New York, as currently in effect, and we express no opinion
of the effect of laws of any other jurisdiction on the opinions expressed
herein.

We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to all references to us in the Registration
Statement, the prospectus constituting a part thereof and any amendments
thereto.

                                Very truly yours,

                                /s/ Morrison & Foerster LLP




