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 Objections
Claims 9, 10, and 14 are objected to because of the following informalities:
Claim 9 recites, “said digitized amplified electrical signal.”
The period at the end of this limitation should be changed to a comma or semicolon
The punctuation/bulleting should be revised for consistency with the other claims
Claim 10 recites, “The lidar system according to the claim 9”
This should be amended to recite, “The lidar system according to [[the]] claim 9”
Claim 14 is missing a period at the end of the sentence
Appropriate correction is required.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Rekow (US 2025/0216519 A1) in view of Krishnamachari et al. (US 2019/0086257 A1).
Regarding Claim 9, Rekow teaches a system based on measuring a time of flight ([0005] The measurements collected by a LiDAR channel may be used to determine the distance (“range”) from the device to the surface in the environment that reflected the channel's transmitted optical signal back to the channel's receiver. In some cases, the range to a surface may be determined based on the time of flight of the channel's signal (e.g., the time elapsed from the transmitter's emission of the optical signal to the receiver's reception of the return signal reflected by the surface)), comprising:
an emission device configured to emit light pulses toward a scene at an angle greater than or equal to 5° ([0051] Use of a movable (e.g., oscillating) mirror in this manner may enable the LiDAR system to achieve 90-180-360 degrees of azimuth (horizontal) view while simplifying both the system design and manufacturability)
a reception device ([0036] a LIDAR receiver) comprising:
a photodetector configured to receive pulses reflected or backscattered by at least one element of the scene and to convert said pulses into an electrical signal ([0036] As used herein, “captured signal” may refer to an electrical signal produced by a LIDAR receiver in response to detecting a return signal (e.g., a ‘captured analog signal’ produced by a photodetector, a ‘captured digital signal’ produced by an analog-to-digital converter, etc.) [0053] the emitted laser signal 251 may reflect off an object 258 in its propagation path. The reflected return signal 253 may be coupled to the detector 262),
an amplification circuit configured to amplify said electrical signal ([0063] Photodetector 370 generates an output signal 373 (e.g., “captured signal”) that is amplified by an amplifier 180 (e.g., an analog trans-impedance amplifier (TIA))),
a processing unit for processing said amplified electrical signal, configured to digitize the amplified electrical signal and determine a distance from said at least one element based on said digitized amplified electrical signal ([0064] The amplified captured signal 381 is communicated to receiver 320. As can be seen in FIG. 3B, receiver 320 can include a controller 322, signal processing components 324, and timing circuitry 326... The signal processing components 324 (described in further detail below) can digitize segments of the amplified captured signal 381 that include peak values and process the digitized captured signal to determine whether the characteristics of the light 371 detected by the photodetector 370 match the characteristics of the illumination light 362. If so, the detected light 371 is determined to be an actual return signal, and the timing circuitry 326 can estimate the time of flight of the illumination light from illumination source 360 to a reflective object in the 3-D environment and back to the photodetector 370.),
the amplification circuit comprising a transimpedance amplifier ([0063] Photodetector 370 generates an output signal 373 (e.g., “captured signal”) that is amplified by an amplifier 180 (e.g., an analog trans-impedance amplifier (TIA))).
Rekow is not relied upon as teaching the amplification circuit comprising a transformer comprising a primary and a secondary, a capacitor and an inductor arranged in series with said capacitor, the primary of the transformer being connected to an anode of the photodetector, the secondary being connected to said capacitor, said capacitor being connected to an input of said transimpedance amplifier.
However, Krishnamachari teaches the amplification circuit comprising a transformer comprising a primary and a secondary ([0007] In an embodiment, the present invention provides a light/voltage converter circuit for converting intensity fluctuations of light into an alternating voltage measurement signal. The light/voltage converter circuit includes a photodiode configured to detect the light and a transformer comprising a primary coil and a secondary coil. The primary coil is connected in a series circuit to the photodiode, and the alternating voltage measurement signal is applied to the secondary coil [0016] According to an embodiment of the invention, the useful signal is very effectively separated from the direct component and is made available for further analysis, e.g. processing, amplification, etc), a capacitor and an inductor arranged in series with said capacitor ([0039] The second electrical network N2 can contain series and/or parallel circuits of R, L or C elements), the primary of the transformer being connected to an anode of the photodetector ([0041] In this case (FIG. 4a), the primary coil of the transformer T is located between the anode of the photodiode D and a negative supply voltage), the secondary being connected to said capacitor (Fig. 2 Examiner Note: Fig. 2, reproduced below, shows T2 (the secondary coil of the transformer) connected to N2 (the series and/or parallel circuits of R, L, or C elements)), said capacitor being connected to an input of said transimpedance amplifier ([0018] At the output of the second electrical network, a voltage amplifier can be used [0039] The second electrical network N2 can contain series and/or parallel circuits of R, L or C elements).
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433
634
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Rekow and Krishnamachari are considered to be analogous to the claimed invention because they are bot in the same field of optical receiver circuits for LiDAR systems. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the receiver amplification circuit of Rekow to include the transformer-coupled photodiode front-end and series RLC matching network (N2) of Krishnamachari with a reasonable expectation of success. This modification would have been motivated by the desire to effectively separate high-frequency AC optical pulse signal components from DC photodiode bias currents, eliminate power supply noise, and optimize RF impedance matching to maximize the measurement signal fed to an amplifier.
Specifically, a person of ordinary skill in the art would construct this circuit by taking Rekow’s photodetector (370) and connecting its anode to the primary coil (T1) of Krishnamachari’s transformer (T) (Krishnamachari [0041], Fig. 4a). The secondary coil (T2) of the transformer network is coupled across Krishnamachari’s second network (N2), which contains series-connected inductor and capacitor (LC) elements (Krishnamachari [0038], [0039], Fig. 2). The output of this series LC network (N2) is then directly wired to the input of Rekow’s transimpedance amplifier (180) (Rekow [0063], Krishnamachari [0018]).
By integrating Krishnamachari’s teaching of a transformer-coupled anode and series LC network into Rekow’s receiver amplification circuit, the system can provide DC-free, impedance-matched current-to-voltage conversion prior to stage amplification, drastically increasing signal amplitude and improving signal-to-noise ratio for pulse processing. A person of ordinary skill in the art would recognize that combining these well-known, predictable circuit building blocks would yield the predictable result of an optimized, low-noise front-end receiver capable of detecting weak optical return pulses.
Claims 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Rekow (US 2025/0216519 A1) and Krishnamachari et al. (US 2019/0086257 A1) in further view of Avestruz et al. (US 2021/0376828 A1).
Regarding Claim 10, Rekow is not relied upon as teaching a frequency operating range of the transformer includes the [10MHz; 350 MHz] band.
However, Avestruz teaches a frequency operating range of the transformer includes the [10MHz; 350 MHz] band ([0043] the transformer 104 has a bandwidth from about 1.5 MHz to about 1.2 GHz).
Rekow (as previously modified by Krishnamachari) and Avestruz are considered to be analogous to the claimed invention because they are both in the same field of high-frequency signal coupling and pulse detection electronics for optical/LiDAR systems. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the transformer circuit of Rekow (as previously modified by Krishnamachari) to include a frequency operating range spanning 1.5 MHz to 1.2 GHz of Avestruz with a reasonable expectation of success. This modification would have been motivated by the desire to capture high-speed pulse transitions, maintain signal fidelity, and ensure clean passband transmission across wide frequency spectrums without attenuation. By integrating Avestruz’s teaching of broadband transformer operating frequencies into Rekow (as previously modified by Krishnamachari)’s system, the system can pass high-frequency optical signals reliably across the transformer interface. A person of ordinary skill in the art would recognize that simple substitution of known equivalents to yield predictable results of configuring the transformer parameters would reliably accommodate signal bandwidths including the claimed 10 MHz to 350 MHz range.
Regarding Claim 11, Rekow is not relied upon as teaching a transformation ratio equal to the ratio of the number of turns of the secondary to the number of turns of the primary is strictly greater than 1.
However, Avestruz teaches a transformation ratio equal to the ratio of the number of turns of the secondary to the number of turns of the primary is strictly greater than 1 ([0043] The transformer 104 boosts the control signal v.sub.c by the turns ratio 1:N of the transformer 104. In one example, the turns ratio is 1:2, but other ratios may be used).
Rekow (as previously modified by Krishnamachari) and Avestruz are considered to be analogous to the claimed invention because they are both in the same field of high-frequency signal coupling and pulse detection electronics for optical/LiDAR systems. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the transformer of Rekow (as previously modified by Krishnamachari) to include a step-up turns ratio strictly greater than 1 (such as 1:2) of Avestruz with a reasonable expectation of success. This modification would have been motivated by the desire to boost coupled signal voltage levels prior to downstream amplification and enhance overall signal detection sensitivity. By integrating Avestruz’s teaching of step-up turns ratios (1:N) into Rekow (as previously modified by Krishnamachari)’s system, the system can step up voltage levels across the secondary winding to achieve higher signal magnitude. A person of ordinary skill in the art would recognize that simple substitution of known equivalents to yield predictable results of utilizing a transformer with a turns ratio greater than 1 would predictably amplify the voltage signal fed to the processing stage.
Claims 12-15 are rejected under 35 U.S.C. 103 as being unpatentable over Rekow (US 2025/0216519 A1) and Krishnamachari et al. (US 2019/0086257 A1) in further view of Heidemann et al. (US 5,229,599).
Regarding Claim 12, Rekow is not relied upon as teaching that the capacitor and the inductor satisfy the relationship:
L
+
n
2
L
p
C
>
L
p
C
p
h
with
L
p
the transformer primary inductance,
C
p
h
the photodiode transition capacitance, n the transformation ratio defined by:
n
s
n
p
=
n
with
n
p
and
n
s
the number of primary and secondary turns, respectively.
However, Heidemann teaches that the capacitor and the inductor satisfy the relationship:
L
+
n
2
L
p
C
>
L
p
C
p
h
with
L
p
the transformer primary inductance,
C
p
h
the photodiode transition capacitance, n the transformation ratio defined by:
n
s
n
p
=
n
with
n
p
and
n
s
the number of primary and secondary turns, respectively ([Col. 3, ll. 57]-[Col. 4, ll. 23] The frequency range of the optical receiver can be varied with an additional circuit variation. This variation is present if a tuning capacitor 38 which itself is connected to ground potential is connected to the cathode of photodiode 31. This (loss-free, no noise) tuning capacitor 38 permits the electrically effective length and thus the resonant frequency of the .lambda./4 circuit to be set. The capacitance is connected in parallel with the capacitance 24 of the photodiode. If the .lambda./4 circuit is a n.multidot..lambda./4 circuit (n=1, 3, 5, . . . ), the receiver is tuned to a harmonic series of frequencies. By connecting tuning capacitors 38 (in addition to photodiode 31) it is possible to set almost any desired receiving frequency (e.g. 900 MHz for CT1 and 1900 MHz for DECT)… In the second embodiment an optical broadband receiver is depicted as the broadband amplifying circuit arrangement in FIG. 4. The broadband receiver E depicted comprises a PIN module PM, a .lambda./4 circuit K and a low-ohmic broadband amplifier BK. In the PIN module a PIN photodiode is arranged as light sensitive component PD for converting an optical signal into an electrical signal. Light-sensitive component PD is connected to a transformer UE by way of an inductance L. Inductance L serves to raise the frequency response of the converted signal toward higher frequencies. In transformer UE, the first part of impedance matching takes place between PIN photodiode PD and low-ohmic amplifier BK in a manner known to the person of skill in the art and as described, for example, in European Patent EP 0,372,742 A2.).
Rekow (as previously modified by Krishnamachari) and Heidemann are considered to be analogous to the same invention because they are both in the same field of broadband optical receiver circuits, photodetector signal conditioning, and transformer-coupled front-ends. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the receiver circuit of Rekow (as previously modified by Krishnamachari) to include a tuning capacitor and tuning inductor satisfying the operational relationship
L
+
n
2
L
p
C
>
L
p
C
p
h
as taught by Heidemann with a reasonable expectation of success. This modification would have been motivated by the desire to adjust resonant frequencies, raise high-frequency signal response, and establish desired passband characteristics across the photodetector-transformer interface. By integrating Heidemann’s teaching of tuning capacitors and inductors into Rekow (as previously modified by Krishnamachari)’s system, the system can dynamically tune receiving frequencies and prevent signal attenuation caused by photodiode capacitance. A person of ordinary skill in the art would recognize that modifying the front-end circuit parameters of Rekow (as previously modified by Krishnamachari) in accordance with Heidemann would yield the predictable result of establishing a predefined lower cutoff frequency and optimizing impedance matching across the transformer.
Regarding Claim 13, Rekow is not relied upon as teaching that the inductor satisfies the relationship:
L
>
n
2
L
p
L
p
C
p
h
2
π
f
i
_
b
2
-
1
where:
n
s
n
p
=
n
with
n
p
and
n
s
the number of primary and secondary turns, respectively,
L
p
the inductor of the primary of the transformer,
C
p
h
the photodiode transition capacity,
f
i
_
b
the minimum frequency of interest.
However, Heidemann teaches that the inductor satisfies the relationship:
L
>
n
2
L
p
L
p
C
p
h
2
π
f
i
_
b
2
-
1
where:
n
s
n
p
=
n
with
n
p
and
n
s
the number of primary and secondary turns, respectively,
L
p
the inductor of the primary of the transformer,
C
p
h
the photodiode transition capacity,
f
i
_
b
the minimum frequency of interest ([Col. 3, ll. 57]-[Col. 4, ll. 23] The frequency range of the optical receiver can be varied with an additional circuit variation. This variation is present if a tuning capacitor 38 which itself is connected to ground potential is connected to the cathode of photodiode 31. This (loss-free, no noise) tuning capacitor 38 permits the electrically effective length and thus the resonant frequency of the .lambda./4 circuit to be set. The capacitance is connected in parallel with the capacitance 24 of the photodiode. If the .lambda./4 circuit is a n.multidot..lambda./4 circuit (n=1, 3, 5, . . . ), the receiver is tuned to a harmonic series of frequencies. By connecting tuning capacitors 38 (in addition to photodiode 31) it is possible to set almost any desired receiving frequency (e.g. 900 MHz for CT1 and 1900 MHz for DECT)… In the second embodiment an optical broadband receiver is depicted as the broadband amplifying circuit arrangement in FIG. 4. The broadband receiver E depicted comprises a PIN module PM, a .lambda./4 circuit K and a low-ohmic broadband amplifier BK. In the PIN module a PIN photodiode is arranged as light sensitive component PD for converting an optical signal into an electrical signal. Light-sensitive component PD is connected to a transformer UE by way of an inductance L. Inductance L serves to raise the frequency response of the converted signal toward higher frequencies. In transformer UE, the first part of impedance matching takes place between PIN photodiode PD and low-ohmic amplifier BK in a manner known to the person of skill in the art and as described, for example, in European Patent EP 0,372,742 A2.).
Rekow (as previously modified by Krishnamachari) and Heidemann are considered to be analogous to the claimed invention because they are both in the same field of broadband optical receiver circuits, photodetector signal conditioning, and transformer-coupled front-ends. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the receiver circuit of Rekow (as previously modified by Krishnamachari) to select the tuning inductance to satisfy the mathematical relationship
L
>
n
2
L
p
L
p
C
p
h
2
π
f
i
_
b
2
-
1
as taught by Heidemann with a reasonable expectation of success. This modification would have been motivated by the desire to establish a minimum operating frequency boundary, raise high-frequency response, and prevent signal distortion across the transformer interface. By integrating Heidemann’s teaching of tuning inductors into Rekow (as previously modified by Krishnamachari)’s system, the system can ensure proper passband operation above the minimum frequency of interest. A person of ordinary skill in the art would recognize that sizing the tuning inductor in accordance with Heidemann would yield the predictable result of establishing an inductive lower limit to support signal transmission across the desire frequency band.
Regarding Claim 14, Rekow is not relied upon as teaching that the inductor satisfies the relationship:
0.5
L
s
<
L
<
2
L
s
where L is the inductor and Ls is the secondary inductor of the transformer.
However, Heidemann teaches that that the inductor satisfies the relationship:
0.5
L
s
<
L
<
2
L
s
where L is the inductor and Ls is the secondary inductor of the transformer ([Col. 4, ll. 12-22] In the PIN module a PIN photodiode is arranged as light sensitive component PD for converting an optical signal into an electrical signal. Light-sensitive component PD is connected to a transformer UE by way of an inductance L. Inductance L serves to raise the frequency response of the converted signal toward higher frequencies. In transformer UE, the first part of impedance matching takes place between PIN photodiode PD and low-ohmic amplifier BK in a manner known to the person of skill in the art).
Rekow (as previously modified by Krishnamachari) and Heidemann are considered to be analogous to the claimed invention because they are both in the same field of broadband optical receiver circuits, photodetector signal conditioning, and transformer-coupled front-ends. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the receiver circuit of Rekow (as previously modified by Krishnamachari) to select the tuning inductance L relative to the transformer secondary inductance such that
0.5
L
s
<
L
<
2
L
s
as taught by Heidemann with a reasonable expectation of success. This modification would have been motivated by the desire to match circuit impedances and establish balanced inductive resonance across the photodetector-transformer interface. By integrating Heidemann’s teaching of tuning inductors into Rekow (as previously modified by Krishnamachari)’s system, the system can optimize signal energy transfer and prevent parasitic losses. A person of ordinary skill in the art would recognize that sizing the tuning inductor to be within the order of magnitude of the secondary inductance in accordance with Heidemann would yield the predictable result of properly matching the tuning loop impedance to the transformer winding.
Regarding Claim 15, Rekow is not relied upon as teaching that the capacitor satisfies the relationship
10
n
2
C
p
h
<
C
<
500
n
2
C
p
h
with Cph the photodiode transition capacitor.
However, Heidemann teaches that the capacitor satisfies the relationship
10
n
2
C
p
h
<
C
<
500
n
2
C
p
h
with Cph the photodiode transition capacitor ([Col. 3, ll. 57]-[Col. 4, ll. 2] The frequency range of the optical receiver can be varied with an additional circuit variation. This variation is present if a tuning capacitor 38 which itself is connected to ground potential is connected to the cathode of photodiode 31. This (loss-free, no noise) tuning capacitor 38 permits the electrically effective length and thus the resonant frequency of the .lambda./4 circuit to be set. The capacitance is connected in parallel with the capacitance 24 of the photodiode. If the .lambda./4 circuit is a n.multidot..lambda./4 circuit (n=1, 3, 5, . . . ), the receiver is tuned to a harmonic series of frequencies. By connecting tuning capacitors 38 (in addition to photodiode 31) it is possible to set almost any desired receiving frequency (e.g. 900 MHz for CT1 and 1900 MHz for DECT).).
Rekow (as previously modified by Krishnamachari) and Heidemann are considered to be analogous to the claimed invention because they are both in the same field of broadband optical receiver circuits, photodetector signal conditioning, and transformer-coupled front-ends. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the receiver circuit of Rekow (as previously modified by Krishnamachari) to select the tuning capacitance relative to the photodiode transition capacitance and transformer turns ratio such that
10
n
2
C
p
h
<
C
<
500
n
2
C
p
h
as taught by Heidemann with a reasonable expectation of success. This modification would have been motivated by the desire to establish an adjustable resonant frequency range, compensate for photodiode junction capacitance, and enable tuning to target receiving frequencies across the optical receiver front-end. By integrating Heidemann’s teaching of parallel tuning capacitors into Rekow (as previously modified by Krishnamachari)’s system, the system can precisely set effective resonant lengths without introducing noise. A person of ordinary skill in the art would recognize that sizing the tuning capacitor relative to the reflected photodiode capacitance within the operational bounds in accordance with Heidemann would yield the predictable result of tuning the front-end circuit to desired operational frequencies while compensating for photodiode junction capacitance.
Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Rekow (US 2025/0216519 A1) and Krishnamachari et al. (US 2019/0086257 A1) in further view of Baastians et al. (US 8,072,595 B1).
Regarding Claim 16, Rekow is not relied upon as teaching that the reception device further comprises a so-called damping resistor (Rph) between the photodetector and the transformer primary.
However, Baastians teaches that the reception device further comprises a so-called damping resistor (Rph) between the photodetector and the transformer primary ([Col. 12, ll. 53-57] 100 ohm differential termination resistor R.sub.6 is included to dampen ringing between the inductance in the secondary of the pulse transformer and the capacitance of the APDs and parasitic capacitance of the pc board and mounting of components).
Rekow (as previously modified by Krishnamachari) and Baastians are considered to be analogous to the claimed invention because they are both in the same field of photodetector signal conditioning and transformer-coupled optical receiver circuits. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the receiver circuit of Rekow (as previously modified by Krishnamachari) to include a damping resistor between the photodetector and the transformer primary as taught by Baastians with a reasonable expectation of success. This modification would have been motivated by the desire to suppress parasitic oscillations, prevent unwanted high-frequency ringing, and improve AC pulse fidelity across the transformer interface. By integrating Baastians’s teaching of a termination/damping resistor into Rekow (as previously modified by Krishnamachari)’s system, the system can stabilize fast transient pulses between the photodetector and transformer windings. A person of ordinary skill in the art would recognize that placing a damping resistor in the signal path would yield the predictable result of reliably suppressing LC ringing and improve front-end signal accuracy.
Conclusion
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/E.H.H./Patent Examiner, Art Unit 3645
/HELAL A ALGAHAIM/SPE , Art Unit 3645
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