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 .
Status of Claims
This office action is responsive to the amendment filed 3/6/2026. As directed by the amendment: claims 1, 3-6, 9-10, 12, and 15-16 are amended and claims 2, 7-8, 11, and 14 are cancelled. Thus, claims 1, 3-6, 9-10, 12-13, and 15-16 are currently pending in this application.
Response to Arguments
Applicant's arguments filed 3/6/2026 have been fully considered but they are not persuasive.
On page 9, applicant argues against the rejection made under U.S.C. 103, in view of Zhuang and Jarosinski by arguing against the Jarosinski reference alone, rather than the combination of references. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Applicant argues that the Jarosinski reference generates the reference and ranging signals by splitting a single beam such that the reference and ranging signals have different power levels. How this difference in power is achieved is irrelevant though, since Jarosinski was not relied upon to teach the generation of a reference and ranging optical signal. Jarosinski was only relied upon to teach the difference in power between a reference and ranging optical signal. Therefore, this argument is not convincing.
Furthermore, applicant argues that the Jarosinski reference does not teach the limitation of two separately emitted optical signals. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., “two separately emitted optical signals”) are not recited in the rejected claims. While the preamble optical signal is generated by “a first reference electrical signal”, there is nothing in the claim that states that this same reference electrical signal cannot also drive the emission of a ranging laser signal. The claim does not state that there is a separate electrical signal for the ranging laser signal. The claim also does not state that the ranging laser signal and the preamble optical signal are emitted by separate light sources. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
On page 10 applicant argues against the rejection made under U.S.C. 103, in view of Zhuang and Osborne, by arguing that Osborne does not disclose “transmitting a reference electrical signal based on a preset period, and such a signal is determined through an internal reference link.” MPEP 2141.03 states that a person ordinarily skilled in the art is also a person of ordinary creativity, who would be able to take the inferences and creative steps that a person of ordinary skill in the art would employ. In the apparatus disclosed by Zhuang, the same driving signal that is used to emit pulses is also used as the electronic reference signal. If a person ordinarily skilled in the art were to incorporate the teaching of Osborne (where the reference optical signal is sent based on a preset period) into the apparatus disclosed by Zhuang (where the electronic reference signal is the same as the driving signal for generating pulses), they would possess the creativity needed to conclude that sending an optical signal based on a preset period can be accomplished by sending the electronic reference signal (that is also the driving signal) on a preset period. Therefore, this ground for rejection is maintained.
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.
Note: Claim 1 lists two alternative limitations regarding how “the second measured distance value of the internal signal link” is determined. The first embodiment determines this value optically, whereas the second embodiment determines this value electrically. For this reason, there are two grounds of rejection presented for claim 1, each of them being directed to one of the two alternative embodiments.
Claims 1, 3-4, 6, 13, and 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Zhuang (US 20180038945 A1), in view of Schultz (US 20200103518 A1), further in view of Jarosinski (US 20180045816 A1).
Regarding Claim 1: Zhuang discloses a laser ranging method (Fig. 1, imaging device 10 for measuring distance to object 50) comprising:
emitting a ranging laser signal (Fig. 1, light emitting device 12 emits optical pulse 30 which has measurement portion 34);
receiving a reflected laser signal, wherein the reflected laser signal is formed after the ranging laser signal is reflected by a target object (Fig. 1, return SPAD array 14 receives measurement/return pulse 34 after it has been reflected off object 50 in the scene);
determining a first measured distance value based on a time difference between an emitting time of the ranging laser signal and a receiving time of the reflected laser signal ([0026] the readout circuitry 26 determines the time of flight as the time between the emission of the optical pulse 30 and the arrival time of the returned pulse 34);
determining a second measured distance value of an internal signal link ([0028] and Fig. 1, reference portion 32 of the emitted pulse 30 is directed towards reference SPAD array and a time signal representing the time of flight of the reference pulse is determined); and
obtaining an actual distance value of the target object based on the first measured distance value and the second measured distance value ([0028] the distance to the object is determined based on the difference between the distance represented by the time of flight of the measurement signal and the distance represented by the time of flight of the reference signal)
wherein the determining the second measured distance value of the internal signal link comprises
generating a first reference electrical signal ([0031] controller 28 generates a control signal in the form of a digital pulse);
performing electro-optical conversion on the first reference electrical signal to obtain a preamble optical signal, and emitting the preamble optical signal ([0031] and Fig. 1, the digital pulse is sent to the driver 36 which provides a driving signal to the light emitting device 12 which emits the output optical pulse 30, part of which is the reference pulse 32);
receiving an echo optical signal corresponding to the preamble optical signal wherein the echo optical signal is formed when the preamble optical signal reaches a light receiving device (Fig. 1, reference SPAD array 16 receives the reference pulse 32); and
determining the second measured distance value of the internal signal link based on a time difference between an emitting time of the preamble optical signal and a receiving time of the echo optical signal ([0028] the time the reference signal is received is the time of flight of the reference pulse, which yields distance).
Zhuang does not disclose the second measured distance value is obtained by performing weighted averaging on a plurality of measured distance values of the internal signal link from repeated measurements; … wherein emission power of the preamble optical signal is less than emission power of the ranging lase signal.
Schultz teaches the use of weighted averaging of measured distances to obtain a distance measurement ([0027] averaging the dynamic possibilities of the distance measurement and applying more weight to measurements that are more probably than others, and making a determination based on a weighted average).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the distance determination disclosed by Zhuang, such that a weighted averaging is used to determine the second distance, where measurements that are more probably than others receive a higher weight, as taught by Schulz. This would be applying the known technique of weighted averaging among a plurality of measured values, in to a method ready for improvement to yield the predictable result of determining a measured distance. See MPEP 2141.III KSR Rationale D.
This combination of Zhuang and Schultz still does not teach that in the determination of the second measured distance value of the internal signal link, the emission power of the preamble optical signal is less than emission power of the ranging laser signal.
However, Jarosinski teaches a laser ranging method that uses an internal reference path (Fig. 4, beam 422), and wherein the emission power of the preamble optical signal is less than an emission of the ranging laser signal ([0048] a “small fraction of a transmitted beam 412” is split as a reference beam, while the rest is directed to the environment). Since only a small fraction of the transmitted beam is used as the reference beam and the rest is used as the measurement beam, the power of the reference signal is less than the power of the measurement signal.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, to modify the pulse emission taught by Zhuang and Schultz, such that the reference pulse has less power than the pulse directed to the environment, as taught by Jarosinski. This is simply another design option for determining how much power a reference and ranging beam should have, and “Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art” (MPEP 2141.III KSR Rationale F).
This combination of Zhuang, Schultz, and Jarosinski, also does not disclose that determining the second measured distance value of the internal signal link comprises: generating a second reference electrical signal; determining transmission duration of the second reference electrical signal in the internal signal link; and determining the second measured distance value of the internal signal link based on the transmission duration, wherein the second reference electrical signal is sent based on a preset period. However, this limitation is listed in the alternative as one of the ways for determining the second measured distance value of the internal signal link. Claim mapping for this alternative limitation in claim 1 can be found later in this office action.
Regarding Claim 3: Zhuang, in view of Schultz and Jarosinski, teaches the laser ranging method according to claim 1.
Zhuang further discloses: wherein the obtaining the actual distance value of the target object based on the first measured distance value and the second measured distance value comprises:
calculating the actual distance value of the target object according to the following formula:
1
2
×
(
c
×
T
1
-
c
×
T
2
)
wherein c represents a speed of light, T1 represents the time difference between the emitting time of the ranging laser signal and the receiving time of the reflected laser signal, and T2 represents the time difference between the emitting time of the preamble optical signal and the receiving time of the echo optical signal ([0028] “the distance to the object 50 may be determined based on the difference between the time a signal representing detection of the return portion 34 of the optical pulse 30 is received by the readout circuitry 26, and the time a signal representing detection of the reference portion 32 is received by the readout circuitry 26”). Zhuang discloses a direct time of flight system that determines distance using the flight time of a pulse, as opposed to a system that determines distance by measuring a phase difference or beat frequency for example. A person of ordinary skill in the art would readily conclude that since the distance is measured based on a time difference between a pulse reflected off an object and a pulse traveling an internal reference path, that Zhuang employs this same, commonly used, equation where distance is equal to half of the time difference multiplied by the speed of light.
Regarding Claim 4: Zhuang, in view of Schultz and Jarosinski, teaches the laser ranging method according to claim 1. Zhuang further discloses wherein the preamble optical signal and the ranging laser signal are sent at the same time ([0020], [0028] and Fig. 1, the reference and measurement signals are emitted simultaneously since they are controlled by the same driver and the distance to the object is represented by the time difference between (1) the time an echo pulse is received and (2) the time the reference signal is received).
Regarding Claim 6: Zhuang, in view of Schultz and Jarosinski, teaches the laser ranging method according to claim 1. Zhuang further discloses wherein the preamble optical signal is sent when a power-on instruction is detected ([0031] the output optical pulse 30, part of which is reference pulse 32, is sent when the driver 36 receives a signal to drive the light emitting device 12 to emit the pulse. Driver 36 receives this signal from the controller 28. This digital signal is the ‘power-on’ instruction that results in the pulse being emitted).
Regarding Claim 13: Zhuang, in view of Schultz and Jarosinski, teaches the laser ranging method according to claim 1. Zhuang further discloses wherein the internal signal link comprises an internal emission link and an internal receiving link (Fig. 1, inside the imaging device is a light emitting diode 12 and SPAD arrays 16 and 14 for detecting reference and measurement pulses respectively);
wherein the internal emission link comprises a control unit, a drive unit, and a laser device (Fig. 1, controller 28, VCSEL driver 36, and light emitting device 12), and
wherein the internal receiving link comprises a photoelectric receiving device, and the control unit (Fig. 1, SPAD arrays 14 and 16 and control unit 28 are connected to readout circuitry 26).
This combination of Zhuang, Schultz, and Jarosinski, does not expressly teach the use of an analog to digital converter.
However, Jarosinski further teaches the use of an ADC for determining time measurements (Fig. 4, ADC 470 is used to determine detection time of light incident on the sensor 460).
It would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the readout circuitry in the system taught by Zhuang, Schultz, and Jarosinski, such that an ADC is used for processing detection signals as taught by Jarosinski. This would be a simple substitution of one type of readout circuitry for another type of readout circuitry that would yield the predictable result of determining the time at which the optical signal was incident on the detector. See MPEP 2141.III KSR Rationale B.
Regarding Claim 15: Zhuang discloses a laser ranging apparatus (Fig. 1, imaging device 10) wherein the apparatus comprises:
an emission unit, configured to emit a ranging laser signal (Fig. 1, light emitting device 12 that emits pulse 30, part of which is measurement pulse 34);
a receiving unit, configured to receive a reflected laser signal, wherein the reflected laser signal is formed after the ranging laser signal is reflected by a target object (Fig. 1, return SPAD array 14, which receives measurement pulse 34 which has been reflected off object 50); and
a control unit, configured to determine a first measured distance value based on a time difference between an emitting time of the laser ranging signal and a receiving time of the reflected laser signal (Fig. 1, controller 28 and readout circuitry 26; [0026] an estimated distance to the object can be determined based on the time between the transmission of the optical pulse 30 and the detection of measurement pulse 34);
wherein the control unit is further configured to determine a second measured distance value of an internal signal link (Fig. 1 and [0027]-[0028] a reference portion 32 of the pulse 30 is detected at reference SPAD array 16 and this is to account for delays through the imaging device circuitry); and
wherein the control unit is further configured to obtain an actual distance value of the target object based on the first measured distance value and the second measured distance value ([0028] the distance to the object is determined based on the difference between the distance represented by the time of flight of the measurement signal and the distance represented by the time of flight of the reference signal),
wherein to determine the second measured distance value of the internal signal link, the control unit is configured to:
generate a first reference electrical signal ([0031] controller 28 generates a control signal in the form of a digital pulse);
perform electro-optical conversion on the first reference electrical signal to obtain a preamble optical signal, and emit the preamble optical signal ([0031] and Fig. 1, the digital pulse is sent to the driver 36 which provides a driving signal to the light emitting device 12 which emits the output optical pulse 30, part of which is the reference pulse 32);
receive an echo optical signal corresponding to the preamble optical signal wherein the echo optical signal is formed when the preamble optical signal reaches a light receiving device (Fig. 1, reference SPAD array 16 receives the reference pulse 32); and
determine the second measured distance value of the internal signal link based on a time difference between an emitting time of the preamble optical signal and a receiving time of the echo optical signal ([0028] the time the reference signal is received is the time of flight of the reference pulse, which yields distance); OR wherein to determine the second measured distance value of the internal signal link, the control unit is configured to: generate a second reference electrical signal; determine transmission duration of the second reference electrical signal in the internal signal link; determine the second measured distance value of the internal signal link based on the transmission duration, wherein the second reference electrical signal is sent based on a preset period.
Zhuang does not disclose the second measured distance value is obtained by performing weighted averaging on a plurality of measured distance values of the internal signal link from repeated measurements; … wherein emission power of the preamble optical signal is less than emission power of the ranging lase signal.
Schultz teaches the use of weighted averaging of measured distances to obtain a distance measurement ([0027] averaging the dynamic possibilities of the distance measurement and applying more weight to measurements that are more probably than others, and making a determination based on a weighted average).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the distance determination disclosed by Zhuang, such that a weighted averaging is used to determine the second distance, where measurements that are more probably than others receive a higher weight, as taught by Schulz. This would be applying the known technique of weighted averaging among a plurality of measured values, in to a method ready for improvement to yield the predictable result of determining a measured distance. See MPEP 2141.III KSR Rationale D.
This combination of Zhuang and Schultz still does not teach that in the determination of the second measured distance value of the internal signal link, the emission power of the preamble optical signal is less than emission power of the ranging laser signal.
However, Jarosinski teaches a laser ranging method that uses an internal reference path (Fig. 4, beam 422), and wherein the emission power of the preamble optical signal is less than an emission of the ranging laser signal ([0048] a “small fraction of a transmitted beam 412” is split as a reference beam, while the rest is directed to the environment). Since only a small fraction of the transmitted beam is used as the reference beam and the rest is used as the measurement beam, the power of the reference signal is less than the power of the measurement signal.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, to modify the pulse emission taught by Zhuang and Schultz, such that the reference pulse has less power than the pulse directed to the environment, as taught by Jarosinski. This is simply another design option for determining how much power a reference and ranging beam should have, and “Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art” (MPEP 2141.III KSR Rationale F).
Regarding Claim 16: Zhuang discloses a LiDAR, comprising a processor and a memory (Fig. 5 and [0055] where electronic device 400 has the imaging processor described in the disclosure, with microprocessor 402 and memory 406) wherein the memory stores a computer program, and the computer program is capable of being loaded by the processor to perform a method which further comprises ([0055] the microprocessor is coupled to the imaging device 100 and send and receives signals to the controller 28 which controls the imaging device):
emitting a ranging laser signal (Fig. 2, imaging device 100 has light emitting device 12 that emits pulse 30);
receiving a reflected laser signal, wherein the reflected laser signal is formed after the ranging laser signal is reflected by a target object (Fig. 2, return SPAD array 14 receiving light 34 that reflected off object 50);
determining a first measured distance value based on a time difference between an emitting time of the ranging laser signal and a receiving time of the reflected laser signal ([0040] the imaging device 100 is similar to imaging device 10 of Fig. 1; [0026] the distance to the object 50 can be estimated by measuring time delay between emission of pulse 30 and detection of pulse at SPAD array 14);
determining a second measured distance value of an internal signal link (Fig. 2, [0041]-[0042] an internal digital signal is routed from the VCSEL driver 36 to the reference front end circuitry 20 to yield a reference time); and
obtaining an actual distance value of the target object based on the first measured distance value and the second measured distance value ([0042] the distance to the object is determined based on the time difference between the time of flight of the measurement pulse and the reference time of the digital signal that has been routed through the reference front end circuitry 20 and reference routing channel 24)
wherein the determining the second measured distance value of the internal signal link comprises
generating a first reference electrical signal ([0031] controller 28 generates a control signal in the form of a digital pulse);
performing electro-optical conversion on the first reference electrical signal to obtain a preamble optical signal, and emitting the preamble optical signal ([0031] and Fig. 1, the digital pulse is sent to the driver 36 which provides a driving signal to the light emitting device 12 which emits the output optical pulse 30, part of which is the reference pulse 32);
receiving an echo optical signal corresponding to the preamble optical signal wherein the echo optical signal is formed when the preamble optical signal reaches a light receiving device (Fig. 1, reference SPAD array 16 receives the reference pulse 32); and
determining the second measured distance value of the internal signal link based on a time difference between an emitting time of the preamble optical signal and a receiving time of the echo optical signal ([0028] the time the reference signal is received is the time of flight of the reference pulse, which yields distance); OR determining the second measured distance value of the internal signal link comprises: generating a second reference electrical signal; determining transmission duration of the second reference electrical signal in the internal signal link; and determining the second measured distance value of the internal signal link based on the transmission duration, wherein the second reference electrical signal is sent based on a preset period.
Zhuang does not disclose the second measured distance value is obtained by performing weighted averaging on a plurality of measured distance values of the internal signal link from repeated measurements; … wherein emission power of the preamble optical signal is less than emission power of the ranging lase signal.
Schultz teaches the use of weighted averaging of measured distances to obtain a distance measurement ([0027] averaging the dynamic possibilities of the distance measurement and applying more weight to measurements that are more probably than others, and making a determination based on a weighted average).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the distance determination disclosed by Zhuang, such that a weighted averaging is used to determine the second distance, where measurements that are more probably than others receive a higher weight, as taught by Schulz. This would be applying the known technique of weighted averaging among a plurality of measured values, in to a method ready for improvement to yield the predictable result of determining a measured distance. See MPEP 2141.III KSR Rationale D.
This combination of Zhuang and Schultz still does not teach that in the determination of the second measured distance value of the internal signal link, the emission power of the preamble optical signal is less than emission power of the ranging laser signal.
However, Jarosinski teaches a laser ranging method that uses an internal reference path (Fig. 4, beam 422), and wherein the emission power of the preamble optical signal is less than an emission of the ranging laser signal ([0048] a “small fraction of a transmitted beam 412” is split as a reference beam, while the rest is directed to the environment). Since only a small fraction of the transmitted beam is used as the reference beam and the rest is used as the measurement beam, the power of the reference signal is less than the power of the measurement signal.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, to modify the pulse emission taught by Zhuang and Schultz, such that the reference pulse has less power than the pulse directed to the environment, as taught by Jarosinski. This is simply another design option for determining how much power a reference and ranging beam should have, and “Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art” (MPEP 2141.III KSR Rationale F).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Zhuang (US 20180038945 A1), in view of Schultz (US 20200103518 A1), further in view of Jarosinski (US 20180045816 A1), further in view of Osborn (US 20220155456 A1).
Zhuang, in view of Schultz and Jarosinski, teaches the laser ranging method according to claim 1. They do not expressly disclose that the preamble optical signal is sent based on a preset period.
However, Osborne teaches a laser ranging method that utilizes an internal optical reference path to obtain a reference time for more accurately determining distance to an object (Fig. 6, method 600) where the preamble optical signal is sent based on a preset period ([0091] there is a predetermined light pulse schedule for emitting pulses, where a plurality of pulses are emitted after respective time delays).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, to modify the pulse emission in the system taught by Zhuang, Schultz, and Jarosinski, such that there is a predetermined light pulse schedule for emitting pulses as taught by Osborne. Since the apparatus disclosed by Zhuang is configured such that the same signal that is used to emit pulses is also used to generate a reference signal, having scheduled pulse emission times would result in the reference optical signal also being emitted at the same pulse emission times. This would mean the reference signal is sent based on a preset period. The use of a predetermined schedule for emitting pulses would be applying a known technique to a known device ready for improvement to yield the predictable result of emitting a series of pulses to obtain a series of distance measurements. See MPEP 2141.III KSR Rationale D.
Claims 1, 9-10, and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Zhuang (US 20180038945 A1), in view of Schultz (US 20200103518 A1), further in view of a second embodiment of Zhuang, further in view of Osborn (US 20220155456 A1).
Regarding Claim 1: Zhuang discloses a laser ranging method (Fig. 1, imaging device 10 for measuring distance to object 50) comprising:
emitting a ranging laser signal (Fig. 1, light emitting device 12 emits optical pulse 30 which has measurement portion 34);
receiving a reflected laser signal, wherein the reflected laser signal is formed after the ranging laser signal is reflected by a target object (Fig. 1, return SPAD array 14 receives measurement/return pulse 34 after it has been reflected off object 50 in the scene);
determining a first measured distance value based on a time difference between an emitting time of the ranging laser signal and a receiving time of the reflected laser signal ([0026] the readout circuitry 26 determines the time of flight as the time between the emission of the optical pulse 30 and the arrival time of the returned pulse 34);
determining a second measured distance value of an internal signal link ([0028] and Fig. 1, reference portion 32 of the emitted pulse 30 is directed towards reference SPAD array and a time signal representing the time of flight of the reference pulse is determined); and
obtaining an actual distance value of the target object based on the first measured distance value and the second measured distance value ([0028] the distance to the object is determined based on the difference between the distance represented by the time of flight of the measurement signal and the distance represented by the time of flight of the reference signal).
This current embodiment of Zhuang does not disclose: the second measured distance value is obtained by performing weighted averaging on a plurality of measured distance values of the internal signal link from repeated measurements; or wherein the determining the second measured distance value of the internal signal link comprises: generating a second reference electrical signal; determining a transmission duration of the second reference electrical signal in the internal signal link; and determining the second measured distance value of the internal signal link based on the transmission duration, wherein the second reference electrical signal is sent based on a preset period.
Schultz teaches the use of weighted averaging of measured distances to obtain a distance measurement ([0027] averaging the dynamic possibilities of the distance measurement and applying more weight to measurements that are more probably than others, and making a determination based on a weighted average).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the distance determination disclosed by Zhuang, such that a weighted averaging is used to determine the second distance, where measurements that are more probably than others receive a higher weight, as taught by Schulz. This would be applying the known technique of weighted averaging among a plurality of measured values, in to a method ready for improvement to yield the predictable result of determining a measured distance. See MPEP 2141.III KSR Rationale D.
This combination of Zhuang and Schultz still does not teach wherein the determining the second measured distance value of the internal signal link comprises: generating a second reference electrical signal; determining a transmission duration of the second reference electrical signal in the internal signal link; and determining the second measured distance value of the internal signal link based on the transmission duration, wherein the second reference electrical signal is sent based on a preset period.
However, a further embodiment of Zhuang teaches wherein the determining the second measured distance value of the internal signal link further comprises:
generating a second reference electrical signal; determining transmission duration of the second reference electrical signal in the internal signal link ([0041]-[0042] and Figs. 1 and 2, the electrical reference path receives the driving signal that is also applied to the light emitting device 12, and it is routed through the reference front end circuitry 20 and routing channel 24 to yield a reference time. In Fig. 1, it would take the path that bypasses the reference SPAD array 16); and
determining the second measured distance value of the internal signal link based on the transmission duration ([0042] “the reference signal that is directed to reference front end circuitry and eventually towards the readout circuitry serves as a reference time that is used in determining a more accurate distance measurement to object.” [0045] the distance can be determined based on a difference between the time of flight of the measurement signal and the time corresponding to the digital reference signal).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, to modify the determination of a second distance in the method taught by Zhuang and Schultz, such that the second distance that is measured is an electronic path as taught by a further embodiment of Zhuang. This could be easily accomplished because the imaging device 10 of Fig. 1 already has this electronic reference path that bypasses the reference SPAD array 16, and the switching element 38 can be used to selectively couple between which reference path is to be used, as described in paragraph [0045]. Making this modification, to use the electronic reference path rather than the optical one, would be beneficial because it can reduce power consumption in applications that do not need absolute range accuracy (Zhuang, [0045]).
However, this combination does not teach that the second reference electrical signal is sent based on a preset period.
Osborne teaches a laser ranging method that utilizes an internal reference path to obtain a reference time for more accurately determining distance to an object (Fig. 6, method 600) where the reference signal is sent based on a preset period ([0091] there is a predetermined light pulse schedule for emitting pulses, where a plurality of pulses are emitted after respective time delays).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, to modify the pulse emission in the system taught by Zhuang, Schultz, and the second embodiment of Zhuang, such that there is a predetermined light pulse schedule for emitting pulses as taught by Osborne. Since the apparatus disclosed by Zhuang is configured such that the same driving signal that is used to emit pulses is also used to as an electronic reference signal, having scheduled pulse emission times would result in the reference signal also being emitted at the same pulse emission times. This would mean the reference signal is sent based on a preset period. The use of a predetermined schedule for emitting pulses would be applying a known technique to a known device ready for improvement to yield the predictable result of emitting a series of pulses to obtain a series of distance measurements. See MPEP 2141.III KSR Rationale D.
This combination does not teach the alternative limitation: wherein the determining the second measured distance value of the internal signal link comprises: generating a first reference electrical signal; performing electro-optical conversion on the first reference electrical signal to obtian a preamble optical signal, and emitting the preamble optical signal; receiving an echo optical signal corresponding to the preamble optical signal, wherein the echo optical signal is formed when the preamble optical signal reaches a light receiving device; and determining the second measured distance value of the internal signal link based on a time difference between an emitting time of the preamble optical signal and a receiving time of the preamble optical signal, wherein emission power of the preamble optical signal is less than emission power of the ranging laser signal. However, this limitation is listed in the alternative as one of the ways for determining the second measured distance value of the internal signal link. Claim mapping for this alternative limitation in claim 1 can be found earlier in this office action.
Regarding Claim 9: Zhuang, in view of Schultz, a further embodiment of Zhuang, and Osborn, teaches the laser ranging method according to claim 1. This second embodiment of Zhuang further teaches: wherein the obtaining the actual distance value of the target object based on the first measured distance value and the second measured distance value comprises:
calculating the actual distance value of the target object according to the following formula:
1
2
×
(
c
×
T
1
-
c
×
T
2
)
wherein c represents a speed of light, T1 represents the time difference between the emitting time of the ranging laser signal and the receiving time of the reflected laser signal, and T2 represents the transmission duration of the second reference electrical signal in the internal signal link ([0042] the reference signal mimics the function of the reference optical signal in the previous embodiment. The reference time that represents the time between the driving signal being sent to the light emitting device 12 and the detection of the signal at the front end circuitry).
Regarding Claim 10: Zhuang, in view of Schultz, a further embodiment of Zhuang, and Osborn, teaches the laser ranging method according to claim 1. This second embodiment of Zhuang further teaches: wherein the second reference electrical signal and the ranging laser signal are sent at the same time ([0041]-[0042] the same driving signal that is sent from the driver 36 to the light emitting device 12 is also sent, as a reference signal, to the reference front end circuitry 20).
Regarding Claim 12: Zhuang, in view of Schultz, a further embodiment of Zhuang, and Osborn, teaches the laser ranging method according to claim 1. This second embodiment of Zhuang further teaches: wherein the second reference electrical signal is sent when a power on instruction is detected ([0040]-[0041] like in the embodiment illustrated in Fig. 1, the controller also sends a signal to the driver 36 to emit a driving signal, which is used both to drive the light emitting device 12 and to provide a reference signal to the reference front end circuitry. This digital signal is the ‘power-on’ instruction that results in the driver sending the driving signal).
Conclusion
THIS ACTION IS MADE FINAL. 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 ISABELLE LIN BOEGHOLM whose telephone number is (571)270-0570. The examiner can normally be reached Monday-Thursday 7:30am-5pm, Fridays 8am-12pm.
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, Yuqing Xiao can be reached at (571) 270-3603. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ISABELLE LIN BOEGHOLM/ Examiner, Art Unit 3645
/YUQING XIAO/ Supervisory Patent Examiner, Art Unit 3645
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