FORM 51-102F3 MATERIAL CHANGE REPORT

Item 1 Name and Address of Company Photon Control Inc. (" Photon Control " or the " Company ")

Item 2 Date of Material Change

July 15, 2021

Item 3 News Release

The Company issued a news release on July 15, 2021, which was disseminated through the facilities of GlobeNewswire and subsequently filed on the Company's SEDAR profile.

Item 4

Summary of Material Change

On July 15, 2021, the Company completed its previously announced acquisition (the " Arrangement ") by MKS Instruments, Inc. (" MKS "). Under the Arrangement, MKS, through its wholly-owned subsidiary 1302998 B.C. Ltd. (" B.C. Ltd. "), has acquired all of the issued and outstanding shares (the " Shares ") of Photon Control in exchange for $3.60 in cash per Share, without interest and less applicable withholding taxes (the " Consideration "). As a result of the Arrangement, Photon Control has become a wholly-owned subsidiary of B.C. Ltd.

Item 5.1

Full Description of Material Change

On July 15, 2021, the Company completed the Arrangement with MKS. Under the Arrangement, MKS, through B.C. Ltd., has acquired all of the Shares of Photon Control in exchange for the Consideration. As a result of the Arrangement, Photon Control has become a wholly-owned subsidiary of B.C. Ltd.

The Arrangement was previously approved by Photon Control securityholders at the annual general meeting of shareholders and special meeting of securityholders of Photon Control held on June 29, 2021 (the " Meeting "). The British Columbia Supreme Court issued a final order approving the Arrangement on July 2, 2021. Additional information regarding the Arrangement is provided in the Company’s management information circular in respect of the Meeting dated May 25, 2021, a copy of which is available on SEDAR under the Company’s profile at www.sedar.com.

The Shares are expected to be delisted from the Toronto Stock Exchange after closing of the markets on July 16, 2021. An application has also been made for the Company to cease to be a reporting issuer in the applicable jurisdictions.

Item 5.2

Disclosure for Restructuring Transactions

Not applicable.

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Item 6 Reliance on subsection 7.1(2) of National Instrument 51-102 Not applicable. Item 7 Omitted Information Not applicable. Item 8 Executive Officer Nigel Hunton President and Chief Executive Officer Telephone: 1-855-574-6866 Item 9 Date of Report July 15, 2021