Exhibit 10.3

SECOND ALLONGE TO RATE PROTECTION TERM NOTE

Reference is made to the Rate Protection Term Note dated September 25, 2002 made
by II-VI Japan Incorporated in favor of PNC Bank, National Association, as
amended by Allonge to Rate Protection Tern Note dated September 25, 2006 (as so
amended, the “Note”).

1. Section 2(a) of the Note is hereby amended to delete the phrase “December 25,
2007” and to insert in lieu thereof the phase “ September 30, 2011”.

2. Except as set for the above, the Note shall remain unamended and in full
force and effect.

Witness the due execution hereof this 23rd day of October, 2006.

 

    II-VI JAPAN INCORPORATED   WITNESS / ATTEST:        

/s/ Miwa Izu

    By:  

/s/ Yasuhiro Sakakibara

  (SEAL) Print Name: Miwa Izu     Print Name:   Yasuhiro Sakakibara   Title:
Accountant     Title:   President       PNC BANK, NATIONAL ASSOCIATION       By:
 

/s/ Troy Brown

      Print Name:   Troy Brown       Title:   Vice President