Semiconductor device manufacturing: process – Making device or circuit emissive of nonelectrical signal
Reexamination Certificate
2000-01-18
2002-02-19
Mulpuri, Savitri (Department: 2881)
Semiconductor device manufacturing: process
Making device or circuit emissive of nonelectrical signal
C438S026000, C438S033000, C438S456000
Reexamination Certificate
active
06348358
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to laser diodes, and in particular to the construction and operation of emitter arrays.
BACKGROUND OF THE INVENTION
Although diode lasers are presently available in linear arrays, or “bars,” the individual emitters are not separately addressable; that is, the lasers must all be on or off. This is due to the thermal and electronic interaction that inevitably results from containment within a single solid structure. “Crosstalk” causes operation of one device to affect nearby devices, thereby producing mutual interference. Accordingly, the current state of the art precludes individual operation of the lasers in a single diode bar; simultaneous device operation ordinarily entails electrically and physically separate devices.
A need therefore exists for multiple-device packages that have closely spaced diodes, but which also permit independent operation of the individual lasers.
DESCRIPTION OF THE INVENTION
Brief Summary of the Invention
The present invention achieves sufficient thermal and electronic isolation among the emitters in a diode bar to permit separate addressability. In accordance with the invention, a laser emitter bar comprises first and second opposed, parallel surfaces each perpendicular to a third surface through which a plurality of emitters direct output. A first surface of the emitter bar is affixed to a “standoff” element that has conductive surfaces connecting each emitter to a power source; these connections are maintained after a series of spaces is formed between the emitters of the emitter bar. The spaces are sufficient (generally 200 &mgr;m to 1000 &mgr;m) to ensure the absence of crosstalk among the emitters. The second surface of the emitter bar is then affixed to a heat sink to form a finished assembly.
In light of their separate addressability, two emitters in a single package may have different output power levels to facilitate, for example, production of image spots having different sizes.
REFERENCES:
patent: 5319725 (1994-06-01), Buchamann et al.
patent: 5521932 (1996-05-01), Marshall
patent: 5861992 (1999-01-01), Gelbart
patent: 5880525 (1999-03-01), Boudreau et al.
patent: 5912872 (1999-06-01), Feldman et al.
patent: 5986819 (1999-11-01), Steinblatt
patent: 0 590 232 (1994-04-01), None
patent: 57 005 381 (1982-01-01), None
patent: 60 211 992 (1985-10-01), None
patent: 61 168 283 (1986-07-01), None
patent: 96 249 70 (1996-08-01), None
Dearman Thomas C.
Foster Josh P.
Sousa John Gary
Mulpuri Savitri
Presstek Inc.
Testa Hurwitz & Thibeault LLP
LandOfFree
Emitter array with individually addressable laser diodes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Emitter array with individually addressable laser diodes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Emitter array with individually addressable laser diodes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2971047