POWER OF ATTORNEY
Know all by these presents that the undersigned hereby constitutes
and appoints Jeffrey W. Acre, D. Mark McMillan and Jo Anne
Schwendinger, and each of them, signing singly, the undersigned's
true and lawful attorney-in-fact to:
(1) prepare and execute in the undersigned's name and on the
undersigned's behalf, in the undersigned's capacity as a
director of II-VI Incorporated (the "Company"), and submit to
the U.S. Securities and Exchange Commission (the "SEC") a Form
ID, including any amendment thereto, and any other document
necessary or appropriate to obtain codes and passwords enabling
the undersigned to make electronic filings with the SEC of
reports required by Section 16(a) of the Securities Exchange Act
of 1934, as amended (the "Exchange Act"), or any rule of
regulation of the SEC;
(2) do and perform any and all acts for an on behalf of the
undersigned which may be necessary or desirable to complete and
execute Forms 3, 4 and 5 with respect to the securities of the
Company beneficially owned by the undersigned in accordance with
Section 16(a) of the Securities Exchange Act of 1934, as amended
(the "1934 Act") and the rules and regulations thereunder and
Form 144 with respect to the securities of the Company
beneficially owned by the undersigned in accordance with Rule
144 under the Securities Act of 1933, as amended (the
"Securities Act"), including executing any such form or any
amendment thereto on behalf of the undersigned and timely filing
any such form with the SEC and any stock exchange or similar
authority; and
(3) take any other action of any type whatsoever in connection
with the foregoing, which, in the opinion of such attorney-in-
fact, may be of benefit to, in the best interest of, or legally
required by, the undersigned, it being understood that the
documents executed by such attorney-in-fact on behalf of the
undersigned pursuant to this Power of Attorney shall be in such
form and shall contain such terms and conditions as such
attorney-in-fact may approve in such attorney-in-fact's
discretion.
The undersigned hereby grants to each such attorney-in-fact  full
power and authority to do and perform any and every act and thing
whatsoever requisite, necessary, or proper to be done in the exercise
of any of the rights and powers herein granted, as fully to all
intents and purposes as the undersigned might or could do if
personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or
such attorney-in-fact's substitute or substitutes, shall lawfully do
or cause to be done by virtue of this power of attorney and the
rights and powers herein granted.
The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not
assuming, nor is the Company assuming, any of the undersigned's
responsibilities to comply with Section 16 of the Exchange Act or
Rule 144 of the Securities Act.
This Power of Attorney shall remain in full force and effect until
the undersigned is no longer required to file Forms 3, 4, 5 and 144
with respect to the undersigned's holdings of and transactions in
securities issued by the Company, unless earlier revoked by the
undersigned in a signed writing delivered to the foregoing attorneys-
in-fact.
IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney
to be executed as of this 27th day of August, 2019.
 /s/ Patricia Hatter
Patricia Hatter