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 .
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.
Response to Amendment
Claims 1-24 are currently pending.
Independent claim(s) 1 and 24 and dependent claims 2, 11-14 and 22 have been amended by applicant’s amendments received 16 March 2026. No new matter has been introduced.
Response to Arguments
Applicant’s arguments, see Remarks, pages 7-9, filed 16 March 2026, with respect to the rejection(s) of claim(s) 1-7, 13-14, 16-18, 2022 and 24 under 35 U.S.C. 102(a)(1) and (a)(2) have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of newly found prior art references in response to the amended claims filed.
In the Remarks, applicant discusses that the priorly cited Wachter et al. (hereinafter Wachter, US 20210132197 A1) does not teach the amended features of claim 1. Firstly, it is noted that Wachter does not explicitly discuss determining a pulse’s rising or falling slope, or that a plurality of voltage values at differing times are collected based on several thresholds. As included in the updated rejection below, Wachter discusses that sampling may be completed continuously to determine timing information, and related voltage values, and this sample-and-hold circuitry logs the values of the pulse intensity versus time.
Secondly, it is noted that Wachter does not teach either determining a slope of the rising/falling edge of the pulse based on a linear regression of the voltage versus time data, nor does Wachter teach relating the inverse cosine of a ratio of a collected rising/falling edge to an expected rising/falling edge slope based on a reflection at a normal angle of incidence. Wachter does not teach these limitations, but upon further search and consideration an obvious combination can be made with the newly found prior art references and Wachter to teach a system where a pulse’s characteristics, such as slope (based on voltage versus time) is fit by a linear regression analysis and then related to an angle of incidence of the laser and the surface of a target object.
Specification
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
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.
Claim(s) 1-14, 16-18, 20-22 and 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wachter et al. (hereinafter Wachter, US 20210132197 A1 in view of Liang et al. (hereinafter Liang, US 20240192338 A1) and further in view of Mimeault (US 20130044310 A1).
Regarding claims 1 and 24, Wachter teaches a lidar system and a method ([0035]) comprising:
a light source configured to emit an optical signal ([0046]; Fig. 1, transmitter (110) includes light emitters (112));
a receiver ([0046]; Fig. 1, receiver (120)) configured to:
detect a received optical signal comprising a portion of the emitted optical signal that is scattered by a surface of a target located a distance from the lidar system ([0049]), wherein the surface is oriented at an angle of incidence with respect to the emitted optical signal ([0061] - [0064]; Figs. 3A and 3B);
and produce an electrical signal corresponding to the received optical signal ([0049]);
wherein the electrical signal comprises a plurality of time values corresponding to respective times at which a voltage signal corresponding to the received optical signal crosses a plurality of respective threshold voltages ([0062] - [0064]; where the system compares amplitude values of the received pulses to at least two threshold values, to continuously sample the pulse and store the light pulse with intensity versus time values);
and a controller configured to determine, based on the electrical signal, the angle of incidence of the surface of the target ([0046], [0065]; Fig. 1 where the controller (130) can utilize information from receiver (120), detector circuit (122) and ADC (123)received pulse width to determine one or more features of the inclined surface/object, which may include angle).
Wachter does not teach estimating a slope of the returned pulse by applying a linear regression, determining a slope of the rising/falling edge of the pulse based on a linear regression of the voltage versus time data, or relating the inverse cosine of a ratio of a collected rising/falling edge to an expected rising/falling edge slope based on a reflection at a normal angle of incidence.
Mimeault teaches estimating a slope of an edge of the received optical signal by applying linear regression to data based on the plurality of time values and the plurality of threshold voltages ([0074] - [0076]; where the slope of a pulse/curve may be fit by linear regression to determine further information about the signal being analyzed).
Liang teaches determining an estimate of cos(
β
) based on a ratio of the estimated slope to an expected slope at normal incidence and applying an inverse cosine operation to determine
β
as the angle of incidence ([0015], [0075] - [0077]; a ratio of the reference pulse width difference and the pulse width difference is used as the 'slope' of the echo pulse, which is used to determine object recognition and classification, and the relationship between intensity of an estimated slope to a normal incidence slope is known to be proportional to cosine of the angle of incidence).
Therefore, to one of ordinary skill in the art before the effective filing date of the claimed invention, it would have been obvious prima facie to modify Wachter to incorporate the teachings of Mimeault to utilize linear regression analysis of the voltage versus time slope data, and the teachings of Liang to utilize a ratio of slopes to relate the slopes to the angle of incidence with a reasonable expectation of success. Using both linear regression of data points to determine a slope and a reference value such as in a ratio with a collected value are well known mathematical analysis processes in the art of LIDAR as a way to determine best fits and normalize values. Liang further notes that the ratio of an measured pulse slope to a normal incidence pulse’s slope can further indicate information such as reflectivity of an object (as noted by Liang, [0003]). Further, to one of ordinary skill in the art at the time of filing, it would be well known that an observed intensity of a reflected signal will decrease in proportion to the cosine of the incidence angle, as taught by Lambert’s cosine Law (see “Empirical Waveform Decomposition and Radiometric Calibration of a Terrestrial Full-Wavelength Laser Scanner”, Hartzell et al., 2015 as a teaching reference to this known relationship and it’s use in LiDAR systems). This known relationship would readily incorporate the ratio of slopes (pulse-width) as taught by Liang into the linear regression fit voltage versus time sampled pulses of Wachter.
Regarding claim 2, Wachter as modified above teaches the lidar system of claim 1, wherein:
the emitted optical signal comprises an emitted pulse of light ([0061] - [0064]; Figs. 3A and 3B, signals (311) are emitted pulses);
the received optical signal comprises a received pulse of light comprising a portion of the emitted pulse of light scattered by the target ([0061] - [0064]; Figs. 3A and 3B, signals (321), (331) are pulses reflected off object);
and determining the angle of incidence of the surface of the target further comprises determining a pulse characteristic of the received pulse of light ([0065]; received/reflected pulse information such as width can be used to determine one or more features of the inclined surface/object, which may include angle).
Regarding claim 3, Wachter as modified above teaches the lidar system of claim 2, wherein the receiver comprises:
a detector configured to produce a photocurrent signal corresponding to the received pulse of light ([0049]);
an electronic amplifier configured to amplify the photocurrent signal to produce a voltage signal that corresponds to the photocurrent signal ([0073]; Fig. 4A amplifier (415) may be included in detector circuit (400));
and a plurality of comparators ([0072] - [0073], [0077]; Fig. 4A, where each photodiode (402) is connected to comparator (410) and sample-and-hold circuit (420)) coupled to a respective plurality of time-to-digital converters (TDCs), wherein:
each comparator is configured to provide an electrical-edge signal to a corresponding TDC when the voltage signal rises above or falls below a particular threshold voltage;
and the corresponding TDC is configured to produce a time value corresponding to a time when the electrical-edge signal was received, wherein the electrical signal produced by the receiver comprises one or more time values produced by one or more TDCs ([0073] - [0078]; Fig. 4A, where processing channels (421n) may run in parallel and sample the photodiode signal to output signals indicative of intensity and timing information, linked to the photodetector signal being compared to a threshold value.)
Regarding claim 4, Wachter as modified above teaches the lidar system of claim 2, wherein
the pulse characteristic comprises an edge slope, duration, rise time, or fall time of the received pulse of light ([0061], [0065]; received/reflected pulse shape information can include rising edge timing, falling edge timing, peak amplitude, pulse width, or any combination thereof).
Regarding claim 5, Wachter as modified above teaches the lidar system of claim 2, wherein
the pulse characteristic comprises a slope of an edge of the received pulse of light ([0061], [0065]; received/reflected pulse shape information can include rising edge timing, falling edge timing, or a combination, where the timing of a rising or falling edge yields its slope).
Regarding claim 6, Wachter as modified above teaches the lidar system of claim 5, wherein
the edge of the received pulse of light is a rising edge ([0061], [0065]; received/reflected pulse shape information can include rising edge timing, falling edge timing, or a combination, where the timing of a rising or falling edge yields its slope).
Regarding claim 7, Wachter as modified above teaches the lidar system of claim 5, wherein
the pulse characteristic further comprises a slope of one or more additional edges of the received pulse of light ([0061], [0065]; received/reflected pulse shape information can include rising edge timing, falling edge timing, or a combination, where the timing of a rising or falling edge yields its slope).
Regarding claim 8, Wachter as modified above teaches the lidar system of claim 5.
Wachter does not teach explicitly comparing slopes of reflected pulses to slopes of reference pulses.
Liang teaches determining the angle of incidence comprises comparing the edge slope of the received pulse of light to a normal-incidence slope ([0006], [0066], slope of returned pulse is determined by information at two threshold amplitudes, known as the pulse width difference, and then compared to a reference pulse width difference, where the reference pulse is a pulse under normal incidence).
Therefore, to one of ordinary skill in the art before the effective filing date of the claimed invention, it would have been obvious prima facie to modify Wachter to incorporate the teachings of Liang to compare the edge slopes of reflected pulses to a reference pulse which is based off of a normal-incidence reflected pulse with a reasonable expectation of success. As Wachter already teaches comparing a reflected pulse’s characteristics to that of a reference pulse, inclusion of pulse slopes as variables of comparison would have a predictable result of increasing recognition accuracy, as noted by Liang ([0044]).
Regarding claim 9, Wachter as modified above teaches the lidar system of claim 8, wherein
the normal-incidence slope is determined previously from a master signal and is stored in a system memory ([0012], [0016], [0093]; the reference pulse may be emitted during a calibration operation, and stored in memory).
Regarding claim 10, Wachter as modified above teaches the lidar system of claim 8, wherein
the normal-incidence slope is based on a measurement of a portion of the emitted pulse of light ([0114]; where the peak amplitude value may be measured by the LIDAR system and/or may be determined or otherwise derived from the transmit power level of the emitted light pulse, which is used to determine the reference pulse).
Regarding claim 11, Wachter as modified above teaches the lidar system of claim 8.
Wachter does not teach forming a ratio of the slopes of the received pulse and the reference pulse.
Liang teaches dividing the edge slope of the received pulse of light by the normal-incidence slope ([0015], [0075] - [0077]; a ratio of the reference pulse width difference and the pulse width difference is used as the 'slope' of the echo pulse, which is used to determine object recognition and classification).
Therefore, to one of ordinary skill in the art before the effective filing date of the claimed invention, it would have been obvious prima facie to modify Wachter to incorporate the teachings of Liang to utilize a ratio of slopes with a reasonable expectation of success. Using a reference value such as in a ratio with a collected value is well known in the art of LIDAR as a way to normalize values, which can further indicate information such as reflectivity of an object (as noted by Liang, [0003]).
Regarding claim 12, Wachter as modified above teaches the lidar system of claim 8, wherein
determining the angle of incidence further comprises determining the angle of incidence from a look-up table based on the edge slope of the received pulse of light ([0042], where a reference pulse width and amplitude may be stored, along with other pulse characteristics such as slope, within a look-up table used for pulse/object identification).
Regarding claim 13, Wachter as modified above teaches
determining the angle of incidence further comprises determining a duration of the received pulse of light ([0061], [0065]; received/reflected pulse information such as width can be used to determine one or more features of the inclined surface/object, which may include angle).
Regarding claim 14, Wachter as modified above teaches
determining the angle of incidence further comprises finding an angle of incidence from a look-up table based on the determined duration of the received pulse of light ([0042], where a reference pulse width and amplitude may be stored, along with other pulse characteristics such as slope, within a look-up table used for pulse/object identification).
Regarding claim 16, Wachter as modified above teaches
determining a pulse energy of the received pulse of light ([0098], the lidar system may use the amplitude of the received pulse);
and calibrating the duration of the received pulse of light to the pulse energy of the received pulse of light ([0098]; where the peak amplitude may be used to determine the pulse width or may use any other suitable technique to measure, determine, or estimate the pulse width of the received light pulse, which one of ordinary skill in the art understands would include normalization of the peak height, which is a form of calibration of data).
Regarding claim 17, Wachter as modified above teaches
the electrical signal comprises a digital electrical signal ([0077], [0080]).
Regarding claim 18, Wachter as modified above teaches
at least part of the controller is included within the receiver ([0046], [0065]; Fig. 1 receiver (120) includes detector circuit (122) and ADC (123)).
Regarding claim 20, Wachter as modified above teaches
the angle of incidence is a first angle of incidence;
and the controller is further configured to:
determine a second angle of incidence;
and identify an object in an environment of the lidar system based at least in part on the first and second angles of incidence ([0061] - [0064], [0104]; Figs. 3A and 3B, where multiple pulses are emitted into the environment and each will be measured and analyzed to yield a first and second surface angle via pulse spreading information, which is utilized to identify objects such as debris).
Regarding claim 21, Wachter as modified above teaches
the lidar system is operating as part of a vehicle and the object is an obstacle located on a path of the vehicle ([0001], [0094]).
Regarding claim 22, Wachter as modified above teaches
the first and second angles of incidence are determined based on different edge slopes of the received optical signal ([0061], [0065]; received/reflected pulse shape information can include rising edge timing, falling edge timing, or a combination, where the timing of a rising or falling edge yields its slope, and both slopes of a single pulse may be utilized instead of two separate pulses for object identification).
Claim(s) 15, 19 and 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wachter et al. (hereinafter Wachter, US 20210132197 A1) in view of Liang et al. (hereinafter Liang, US 20240192338 A1) and Mimeault (US 20130044310 A1), and further in view of Drummer et al. (hereinafter Drummer, US 10340651 B1)
Regarding claim 15, Wachter as modified above teaches the lidar system of claim 13.
Wachter is silent on utilizing a full-width (FWHM) or half-width (HWHM) half maximum to find the pulse width.
Drummer teaches that the duration of a received pulse of light is a full width at half maximum, or a half width at half maximum, of the received pulse of light (Col. 4, lines 13-48; duration of LIDAR pulses, either emitted or received, may be defined as the full width at half maximum duration of the pulse).
Therefore, to one of ordinary skill in the art before the effective filing date of the claimed invention, it would have been obvious prima facie to modify Wachter to incorporate the teachings of Drummer to utilize FWHM or HWHM values to define the width, or duration, of a pulse with a reasonable expectation of success. FWHM is a well-known metric utilized in describing peak widths, or in this case specifically, a pulse duration within a LIDAR system which emits pulses of light into an environment.
Regarding claim 19, Wachter as modified above teaches the lidar system of claim 1.
Wachter does not teach the specifics of the scanner optics within the system.
Drummer teaches a scanner configured to direct the emitted optical signal into a field of regard of the lidar system, wherein the scanner comprises a rotating polygon mirror (Col. 6, lines 19 - 43; where a scanning mirror, such as a rotating polygonal mirror, may be used to scan the environment).
Therefore, to one of ordinary skill in the art before the effective filing date of the claimed invention, it would have been obvious prima facie to modify Wachter to incorporate the teachings of Drummer to specifically use a polygonal mirror within the transmit aperture to direct outgoing beams with a reasonable expectation of success. Wachter notes that the transmit aperture (Fig. 1, (113)) may include any suitable components such as a mirror to direct the light pulses being emitted ([0047]), and therefore including the polygonal mirror of Drummer would have a predictable result of controlling the scanning of the emitted beams into the environment where the system of Wachter is operated.
Regarding claim 23, Wachter as modified above teaches the lidar system of claim 1.
Wachter does not teach that the system is a frequency-modulated continuous wave system.
Drummer teaches a LIDAR system, wherein the emitted optical signal comprises a frequency-modulated (FM) output-light signal;
the light source is further configured to emit a FM local-oscillator optical signal that is coherent with the FM output-light signal;
and the receiver is further configured to coherently mix the received optical signal and the FM local-oscillator optical signal, wherein the electrical signal produced by the receiver corresponds to the coherent mixing of the received optical signal and the FM local- oscillator signal (Col. 12, lines 17-54; where the LIDAR pulsed system may be an FMCW system which mixes the returned light with emitted light where the beat frequency gives information on distance and/or velocity of objects).
Therefore, to one of ordinary skill in the art before the effective filing date of the claimed invention, it would have been obvious prima facie to modify Wachter to incorporate the teachings of Drummer to further use a system which uses a local oscillator signal as a reference to not only compare received echo signals to, but to combine signals within an FMCW system to use beat frequencies to obtain further information about the objects in the environment with a reasonable expectation of success. Wachter discusses using a reference beam which is a pulse reflected off a known surface which is orthogonal to the beam ([0005]), and this could incorporate the local oscillator of Drummer with predictable results, as FMCW is common in LIDAR systems where pulse shape is important or may yield information about the objects.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Berger et al. (US 20200172095 A1) teaches a LIDAR system configured to emit pulses of laser light and to then compare the width of returned pulses, having been reflected from the environment, to determine an orientation or surface angle of an object or surface within the environment.
Lipson et al. (US 20180373260 A1) teaches a vehicle equipped LIDAR system, for hazard avoidance, which emits a pulse and then analyzes the pulse width of the reflected pulse to determine an orientation of a target surface.
Shu et al. (US 20180299552 A1) teaches a LIDAR device and system which analyzes returned pulses for variance from the emitted beam pulse, and includes electronics such as amplifiers, counters which compare signals to thresholds, and time-to-digital converters.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Kara Richter whose telephone number is (571)272-2763. The examiner can normally be reached Monday - Thursday, 8A-5P EST, Fridays are variable.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Helal Algahaim can be reached at (571) 270-5227. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/K.M.R./Examiner, Art Unit 3645
/HELAL A ALGAHAIM/SPE , Art Unit 3645
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