THERMO OPTEK CORP

FY: Jan 1 2000

FY: Jan 1 2000

Q: Oct 2 1999

Q: Jul 3 1999

Q: Apr 3 1999

FY: Jan 2 1999

Q: Oct 3 1998

Q: Jul 4 1998

Q: Apr 4 1998

FY: Jan 3 1998

Q: Nov 5 1997

Q: Jun 28 1997

Q: Mar 29 1997

FY: Apr 24 1997

FY: Dec 28 1996

Q: Nov 13 1996

Q: Sep 28 1996

Q: Aug 6 1996

5,7

5,7

5

1

Current report pursuant to Section 13 or 15(d)

5

Certification of termination of registration of a class of securities (Section 12(b))

Registration of Securities on Exchange (amendment)

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Post-effective amendment to a registration statement

Post-effective amendment to a registration statement

Post-effective amendment to a registration statement

Withdrawal of a registration statement

Registration statement under Securities Act of 1933

Registration (IPO) statement under Securities Act of 1933

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Prospectus filed under Rule 424(b)(1)

Amended Initial Registration Statement

Registration of Securities on Exchange

Amended Initial Registration Statement

Definitive Proxy Statement

Definitive Proxy Statement

Definitive Proxy Statement

THERMO INSTRUMENT SYSTEMS INC

THERMO INSTRUMENT SYSTEMS INC

THERMO INSTRUMENT SYSTEMS INC

THERMO INSTRUMENT SYSTEMS INC

THERMO ELECTRON CORP

THERMO ELECTRON CORP

THERMO ELECTRON CORP