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                                                                     EXHIBIT 5.1

            [LETTERHEAD OF COOLEY GODWARD CASTRO HUDDLESON & TATUM]



June 14, 1996



Tylan General, Inc.
15330 Avenue of Science
San Diego, CA 92128

Ladies and Gentlemen:

You have requested our opinion with respect to certain matters in connection
with the filing by Tylan General, Inc. (the "Company") of a Registration
Statement on Form S-4 (the "Registration Statement") with the Securities and
Exchange Commission covering the offering of up to 1,470,000 shares of the
Company's Common Stock, $.001 par value (the "Shares").

In connection with this opinion, we have examined the Registration Statement and
related Prospectus, your Certificate of Incorporation and By-laws, as amended,
and such other documents, records, certificates, memoranda and other instruments
as we deem necessary as a basis for this opinion. We have assumed the
genuineness and authenticity of all documents submitted to us as originals, the
conformity to originals of all documents submitted to us as copies thereof and
the due execution and delivery of all documents where due execution and delivery
are a prerequisite to the effectiveness thereof.

On the basis of the foregoing, and in reliance thereon, we are of the opinion
that the Shares, when issued in accordance with the Registration Statement and
related Prospectus, will be validly issued, fully paid and nonassessable.

We consent to the reference to our firm under the caption "Legal Matters" in the
Prospectus included in the Registration Statement and to the filing of this
opinion as an exhibit to the Registration Statement.

Sincerely,




COOLEY GODWARD CASTRO
HUDDLESON & TATUM




By:  /s/ D. Bradley Peck
   ---------------------------------
     D Bradley Peck, Esq.