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                                                                     EXHIBIT 2.1

                          AMENDMENT NO. 2 TO AGREEMENT
                               AND PLAN OF MERGER


This Amendment No. 2 (the "Amendment"), dated as of March 27, 2000, is entered
into by and among Photronics, Inc., a Connecticut corporation ("Parent"), AL
Acquisition Corp., a California corporation and a wholly owned subsidiary of
Parent ("Merger Sub"), and Align-Rite International, Inc., a California
corporation (the "Company").

WHEREAS, Parent, Merger Sub and the Company have previously executed and
delivered that certain Agreement and Plan of Merger, dated as of September 15,
1999, by and among Parent, Merger Sub and the Company, as amended by Amendment
No. 1, dated as of January 10, 2000, by and among Parent, Merger Sub and the
Company (the "Merger Agreement"); and

WHEREAS, Parent, Merger Sub and the Company desire to amend the Merger Agreement
as set forth herein and pursuant to Section 7.3 of the Merger Agreement

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and
agreements herein contained, and intending to be legally bound hereby, Parent,
Merger Sub and Company hereby agree as follows:

1. Definitions. Capitalized terms used herein but not expressly defined shall
have the meanings accorded such terms in the Merger Agreement.

2. Amendment of Section 5.17 of the Merger Agreement. Section 5.17 of the Merger
Agreement is hereby amended and restated to read, in its entirety, as follows:

"Section 5.17. Sale of Shares by Parent. Parent, prior to the Effective Date,
will sell shares of Parent Common Stock acquired by it within the two years
preceding the Effective Date so that the accounting by the Parent of the
business combination to be effected by the Merger as a "pooling of interests"
will not be adversely affected; provided that Parent shall have until the
earlier of (i) May 30, 2000 or (ii) the 20th day following the satisfaction of
the condition set forth in Section 6.1(d) to effect such sale."

3. Amendments of Section 7.1 of the Merger Agreement. All references in
subsections (b), (c) and (e) of Section 7.1 of the Merger Agreement to "March
31, 2000" are hereby amended to read "May 31, 2000."

4. Authority.

Each of Parent and Merger Sub has full corporate power and authority to enter
into this Amendment. The execution and delivery of this Amendment and the
consummation by each of Parent and Merger Sub of the transactions contemplated
by the Merger Agreement, as amended hereby, have been duly and validly
authorized by the Boards of Directors of Parent and Merger Sub. This Amendment
has been duly and validly executed and delivered by each of Parent and Merger
Sub and constitutes the valid and binding obligation of each of Parent and
Merger Sub, enforceable against each of Parent and Merger Sub in accordance with
its terms (except insofar as enforceability may be limited by bankruptcy,
insolvency, reorganization, moratorium or similar laws affecting creditors'
rights generally, or by principles governing the availability of equitable
remedies).

The Company has full corporate power and authority to enter into this Amendment.
The execution and delivery of this Amendment and the consummation by the Company
of the transactions contemplated by the Merger Agreement, as amended hereby,
have been duly and validly authorized by the Board of Directors of the Company.
This Amendment has been duly and validly executed and delivered by the Company
and constitutes the valid and binding obligation of the Company, enforceable
against the Company in accordance with its terms (except insofar as
enforceability may be limited by bankruptcy, insolvency, reorganization,
moratorium, or similar laws affecting creditors' rights generally, or by
principles governing the availability of equitable remedies).


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5. Governing Law. This Amendment shall be governed by and construed in
accordance with the laws of the State of California, without regard to any
applicable conflicts of law.

6. Counterparts; Effect. This Amendment may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
shall constitute one and the same agreement.

7. Merger Agreement Confirmed. Except as amended hereby, the Merger Agreement is
ratified and confirmed in all respects. Each reference in the Merger Agreement
or any other related document to the Merger Agreement, the Agreement or this
Amendment shall be deemed to a reference to the Merger Agreement as amended
hereby.

        IN WITNESS WHEREOF, Parent, Merger Sub and the Company have caused this
Amendment to be signed by their respective officers thereunto duly authorized,
all as of the date first written above.


                      PHOTRONICS, INC.


                      By:     /s/   MICHAEL J. YOMAZZO
                         ------------------------------------
                            Name:  Michael J. Yomazzo
                            Title:    Vice Chairman


                      By:       /s/ JEFFREY P. MOONAN
                         ------------------------------------
                            Name:  Jeffrey P. Moonan
                            Title:   Executive Vice President
                                     Finance and Administration


                      AL ACQUISITION CORP.


                      By:    /s/  MICHAEL J. YOMAZZO
                         ------------------------------------
                            Name:  Michael J. Yomazzo
                            Title:   President


                      By:   /s/   JEFFREY P. MOONAN
                         ------------------------------------
                            Name: Jeffrey P. Moonan
                            Title:   Vice President


                      ALIGN-RITE INTERNATIONAL, INC.


                      By:     /s/   JAMES L. MACDONALD
                         ------------------------------------
                            Name:  James L. MacDonald
                            Title:   Chairman of the Board,
                                     Chief Executive Officer
                                     and President


                      By:  /s/   PETAR N. KATURICH
                         ------------------------------------
                            Name:  Petar N. Katurich
                            Title:   Vice President of Finance,
                                     Chief Financial Officer