DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1, 5, 6, and 10-12 are rejected under 35 U.S.C. 103 as being unpatentable over Dubos et al. (US Patent 6,445,474 B1) in view of Hayashi (US PG Pub 2006/0203863 A1) and Iguchi et al. (US PG Pub 2002/0181520 A1).
Regarding claim 1, Dubos discloses a laser element module (FIG. 1) comprising:
a first laser module (FIG. 1) comprising a first laser element (101, FIG. 1, col. 1 lines 47-48) and a first capacitor (118, FIG. 1, col. 2 lines ), wherein the first laser element is coupled in series with the first capacitor (an output end of 118 is indirectly connected in series with an anode of 101 via a resistor 125, FIG. 1);
a second laser module (FIG. 1) comprising a second laser element (102, FIG. 1), wherein the first laser module is coupled in series with the second laser module (col. 1 lines 47-48);
a bias current source adapted to provide a first bias current to the first laser element (“A differential amplifier 106 amplifies in known manner the out-of-balance signal of the bridge and controls the average current passing through the laser diode 101 by means of the transistor 107,” col. 1 lines 56-59) and a second bias current to the second laser element (“The average current passing through the laser diode 102 is controlled by two transistors 112 and 113,” col. 1 lines 64-65);
a modulation current source (“A modulation signal is applied to the input 116 of the transmitter, passes through amplification means 117 and is then applied via a coupling capacitor 118 to the assembly of the optical sources 101 and 102 arranged in series,” col. 2 lines 9-12) adapted to provide an alternating current to the first capacitor (“the transmitter includes means for separately supplying DC bias current to the optical sources and for supplying AC modulation current to them in series,” col. 1 lines 27-30).
PNG
media_image1.png
375
502
media_image1.png
Greyscale
Dubos does not disclose the second laser module comprising a second capacitor, wherein the second laser element is coupled in series with the second capacitor.
Hayashi discloses a laser element module (100, FIG. 1, [0024]) comprising: a first laser module (FIG. 1) comprising a first laser element (11, FIG. 1, [0024]) and a first capacitor (41, FIG. 1, [0025]), wherein the first laser element is coupled in series with the first capacitor (FIG. 1); a second laser module (FIG. 1) comprising a second laser element (12, FIG. 1, [0024]) and a second capacitor (42, FIG. 1, [0025]), wherein the second laser element is coupled in series with the second capacitor (FIG. 1), wherein the first laser module is coupled in series with the second laser module (FIG. 1). Hayashi further discloses “The capacitors, 41 and 42, prevent this DC bias current from flowing into the drivers, 31 and 32.” ([0030])
PNG
media_image2.png
342
500
media_image2.png
Greyscale
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the second laser module of Dubos with a second capacitor in series with the second laser element as taught by Hayashi in order to provide DC isolation of the modulation path from the individually bias-current paths while permitting the desired AC modulation to be applied to the series-connected laser elements.
Dubos does not disclose the bias current source and the modulation current source, when active, are arranged to provide a total current to the first laser element and the second laser element which is always larger than a lasing current threshold of the first laser element and a lasing current threshold of the second laser element.
Iguchi discloses a bias current source (11, FIG. 8, where 11 provides Ibias, [0050]) and a modulation current source (14, FIG. 8, where 14 provides Im, [0050]), when active, are arranged to provide a total current (Ibias + Im > Idc, FIG. 6B) to a VCSEL (17, FIG. 8, [0050]) which is always larger than a lasing current threshold (Idc, FIG. 6B) of the VCSEL. Iguchi further discloses “DC bias electric current which is approximately of the level of the threshold electric current I.sub.th is constantly supplied and pulse modulation electric current is coupled thereto, in order to improve the turn-on delay of the laser.” ([0007])
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the bias current source and the modulation current source of Dubos with a total current to the first laser element and the second laser element which being always larger than a lasing current threshold of the first laser element and a lasing current threshold of the second laser element in order to ensure continuous operation of the laser elements during modulation by improving turn-on delay of the laser elements.
Regarding claim 5, Dubos, as modified, discloses the bias current source is adapted to provide the first bias current to the first laser element at a first node between the first capacitor and the first laser element (FIG. 1 of Dubos) and wherein the bias current source is adapted to provide the second bias current to the second laser element at a second node between the second capacitor and the second laser element (FIG. 1 of Hayashi).
Regarding claim 6, Dubos, as modified, discloses the modulation current source is adapted to provide the alternating current to the first laser element via the first capacitor (“A modulation signal is applied to the input 116 of the transmitter, passes through amplification means 117 and is then applied via a coupling capacitor 118 to the assembly of the optical sources 101 and 102 arranged in series,” col. 2 lines 9-12) and wherein the modulation current source is adapted to provide the alternating current to the second laser element via the second capacitor (FIG. 1 of Hayashi).
Regarding claim 10, Dubos discloses a light sensor (103/108, FIG. 1) for sensing a light output from the first laser element and for sensing a light output from the second laser element, wherein the light sensor is adapted to generate a control signal (via 106/111, FIG. 1), wherein the control signal is adapted to provide a determination of an occurrence of lasing of the first laser element and the second laser element (it’s implicitly taught by the photodiodes 103/108).
Regarding claim 11, Dubos discloses a first light sensor (103, FIG. 1) for sensing a light output from the first laser element and a second light sensor (108, FIG. 1) for sensing a light output from the second laser element, wherein the first light sensor is adapted to generate a first control signal (via 106, FIG. 1), wherein the first control signal is adapted to provide a determination of an occurrence of lasing of the first laser element (it’s implicitly taught by the photodiode 103), and wherein the second light sensor is adapted to generate a second control signal (via 111, FIG. 1), wherein the second control signal is adapted to provide a determination of an occurrence of lasing of the second laser element (it’s implicitly taught by the photodiode 108).
Regarding claim 12, Dubos discloses a luminaire (an optical transmitter, see abstract) comprising the laser element module according to claim 1 and a housing (it’s implicitly taught by the optical transmitter) for enclosing the laser element module.
Allowable Subject Matter
Claims 2-4 and 7-9 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Meyers (US Patent 4,991,183) discloses “switching circuit 176 shunts all but a minimum threshold current from laser 46; and the laser is therefore turned off and relegated to a standby status during the on part of the shunt circuit duty cycle.” (col. 9 lines 22-27)
Maron et al. (US Patent 8,599,891 B2) discloses a laser driver for driving series-connected laser modules similar to the claimed invention (see FIG. 1).
NAKAKOHARA et al. (US PG Pub 2022/0376470 A1) discloses a capacitor serially connected with a laser module similar to the claimed invention (see FIG. 1).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to YUANDA ZHANG whose telephone number is (571)270-1439. The examiner can normally be reached M-F 10:30 AM - 6:30 PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, MINSUN HARVEY can be reached at (571)272-1835. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/YUANDA ZHANG/Primary Examiner, Art Unit 2828
Prosecution Insights