EXHIBIT 5.1

                           Morgan, Lewis & Bockius LLP
                               1701 Market Street
                             Philadelphia, PA 19103



May 14, 2001


Universal Display Corporation
375 Phillips Boulevard
Ewing, New Jersey 08618

Re:  Universal Display Corporation
     Registration Statement on Form S-3 Relating to the
     Registration of 1,950,242 shares of Common Stock, $.01 par value
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Ladies and Gentlemen:

We have acted as counsel to Universal Display Corporation, a Pennsylvania
corporation (the "Company"), in connection with the preparation of the subject
Registration Statement on Form S-3 (the "Registration Statement") to be filed
with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Act"), relating to 1,950,242 shares
(the "Shares") of the Company's common stock, par value $.01 per share (the
"Common Stock") to be sold by the selling shareholders named in the Registration
Statement.

In rendering the opinion set forth below, we have examined the Registration
Statement and the exhibits thereto, certain records of the Company's corporate
proceedings as reflected in its minute books and such statutes, records and
other documents as we have deemed relevant. In our examination, we have assumed
the genuineness of documents submitted to us as originals and the conformity
with the originals of all documents submitted to us as copies thereof.

Based on the foregoing, it is our opinion that the Shares are validly issued,
fully paid and nonassessable.

The opinion set forth above is limited to the Business Corporation Law of the
Commonwealth of Pennsylvania, as amended. We hereby consent to the use of this
opinion as Exhibit 5.1 to the Registration Statement. In giving such consent, we
do not thereby admit that we are acting within the category of persons whose
consent is required under Section 7 of the Act and the rules or regulations of
the Commission thereunder.

The opinion expressed herein is solely for your benefit and may be relied upon
only by you.

Very truly yours,

/s/  Morgan, Lewis & Bockius LLP