Gary K. Willis
President and CEO

                                                           FOR IMMEDIATE RELEASE
                                                           ---------------------

                      ZYGO CORPORATION ANNOUNCES LETTER OF
                   INTENT TO ACQUIRE DIGITAL INSTRUMENTS, INC.

MIDDLEFIELD, CONNECTICUT (July 28, 1997)........Zygo Corporation (NASDAQ:ZIGO)
and Digital Instruments, Inc. today announced that they have signed a letter of
intent providing for Zygo's acquisition of Digital Instruments. In the
transaction, which will be accounted for as a pooling-of-interests, Zygo will
acquire all of the outstanding stock of Digital in exchange for 7,000,000 shares
of Zygo's common stock. The proposed acquisition is expected to be completed
prior to the end of calendar year 1997. Consummation of the transaction is
subject to various conditions, including the execution of definitive
documentation, approval of Zygo's shareowners, Zygo's ability to account for the
transaction as a pooling-of-interests, and the receipt by Zygo of a fairness
opinion from its financial advisor.

         Digital Instruments, Inc., located in Santa Barbara, California, is the
world's leading manufacturer of high precision measurement products and systems
which use scanning probe microscopy imaging and metrology technology. These
systems are used in product research and development applications as well as to
improve the production efficiency and manufacturing yields within the data
storage, semiconductor, and other high technology industries.

         Commenting on the synergies created by the acquisition of Digital
Instruments, Gary K. Willis, president and chief executive officer of Zygo,
said, "The combination of Digital and Zygo will be instantly recognized by our
customers as the creation of an enterprise that can provide significantly
enhanced services to them. Digital's scanning probe microscopy technology
complements Zygo's interferometric and confocal measurement capabilities and
broadens our abilities to provide enhanced measurement and yield improvement
solutions to our customers. In addition, with each company's strong
relationships with the industry leaders already existing in both the data
storage and semiconductor industries we will be able to rapidly integrate and
coordinate solutions to these markets.

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We are looking for this combination to rapidly provide enhanced capabilities and
services to our customers." Virgil Elings, Ph.D., president of Digital
Instruments, added, "Our merger with Zygo and the combination of our industry
leadership technology positions will allow us to more effectively pursue the
rapidly growing opportunities in the markets we serve. All of us at Digital are
very pleased and enthused about the combination and the fit with Zygo. We have
been investigating potential partners for some time and see Zygo as the ideal
partner providing exceptional opportunities for all of us."

         The results for Digital Instruments, Inc. for the 12 months ended
December 31, 1996 included net sales of approximately $50 million. Zygo recently
reported its third quarter results for fiscal 1997 with net sales of $61.7
million for the nine months ended March 31, 1997, up some 52% from the
comparable nine-month period of a year earlier; and net earnings of $.83 per
share, excluding nonrecurring acquisition charges, for the nine-month period, a
73% increase from the $.48 per share earnings reported in the comparable
nine-month period of fiscal 1996.

         Zygo Corporation designs, develops, manufactures, and markets high
performance measurement and yield improvement instruments, systems, and
accessories used in high technology industries. Zygo is based in Middlefield,
Connecticut.



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         This press release may contain forward-looking statements within the
meaning of Section 27A of the Securities Act of 1933, as amended, and Section
21E of the Securities Exchange Act of 1934, as amended, which reflect the
Company's current judgment on certain issues. Because such statements apply to
future events, they are subject to risks and uncertainties that could cause the
actual results to differ materially. Important factors which could cause actual
results to differ materially are described in the Company's reports on Form 10-K
and 10-Q on file with the Securities and Exchange Commission.

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July 28, 1997  *    *    *