(12) United States Patent ao) Patent No.: us 6,693,712 Bi
Trezza (45) Date of Patent: Feb. 17,2004
(54) HIGH RATE OPTICAL CORRELATOR IMPLEMENTED ON A SUBSTRATE
(75) Inventor: John A. Trezza, Nashua, NH (US)
(73) Assignee: Teraconnect, Inc., Nashua, NH (US)
( * ) Notice: Subject to any disclaimer, the term ol this patent is extended or adjusted under 35 U.S.C. 154(b) by 19 days.
(21) Appl. No.: 09/723,076
(22) Filed: Nov. 27, 2000
Related U.S. Application Data
(60) Provisional application No. 60/168,488, filed on Dec. 2, 1999.
(51) Int. CI.7 G01B 11/00
(52) U.S. CI 356/399; 235/454
(58) Field of Search
356/399, 400, 401
M. Ajmone Marsan et al, Modelling Slotted Multi-Channel
Ring All-Optical Networks, IEEE, 1997, pp. 146-153.
Marco Ajmone Marsan et al, Access Protocols for Photonic
WDM Multi-Rings with Tunable Transmitters and Fixed
Recievers, SPIE, pp. 59-72, vol. 26921 no date.
Carl Beckmann, Applications: Asynchronous Transfer Mode
and Synchronous Optical Nrtwork, Handbook of Fiber
Optic Data Communication, 1998, pp. 385-414, Academic
Floyd E. Ross, An Overview of FDDI: The Fiber Distrbuted
Data Interface, IEEE Journal on Selected Areas in Commu-
nications, Sep. 1989, pp. 1043-1051, vol. 7 No. 7.
PCT International Search Report dated Jun. 20, 2001 of
International Application No. PCT/US00/42441 filed Dec. 1,
* cited by examiner
Primary Examiner—Karl D. Freeh
(74) Attorney, Agent, or Firm—Maine & Asmus
A high rate optical correlator is implemented on a substrate in which all of the optical devices are referenced to the flat surface of the substrate for optical alignment purposes by mounting the devices thereon. With the substrate surface as a reference point, alignment of the optical pieces is achieved to within a wavelength to eliminate the possibility of a "no correlation" result due to optical misalignment of the optical pieces. Additionally for the active elements, namely the laser, detector and spatial light modulators, interconnection of these devices and to drive sources is accomplished via direct coupling through the substrate so that the devices can communicate with each other through the silicon, thus to eliminate wire bonding and reduce pin count for the approximate 100,000 optical interconnects for a 256/256 array. Moreover, an epoxy frame which is milled at its top surface is used to mount an optical element over an active element for the alignment thereof.
30 Claims, 4 Drawing Sheets