GUNSHOT DETECTION SYSTEM AND METHOD
A device and a method for use in detection of a muzzle flash event is described. The device can include a Photo Detector Array (PDA), sensitive in at least a portion of the NIR and SWIR spectrum, and a filter of electromagnetic radiation selectively passing in this portion a spectral range of low atmospheric transmission, the PDA has an integration time shorter than a duration of the muzzle flash event.
1 . A method for use in detection of a muzzle flash event, the method comprising sensing electromagnetic radiation by a Photo Detector Array (PDA), sensitive in at least a portion of the NIR and SWIR spectrum, wherein said electromagnetic radiation passed through a filter of electromagnetic radiation configured and operable for selectively passing, in said at least portion of the NIR and SWIR spectrum, a spectral range of low atmospheric transmission, said sensing having an integration time shorter than a duration of the muzzle flash event.
2 . The method of claim 1 , wherein said time is shorter than 10 −2 s.
3 - 62 . (canceled)
63 . The method of claim 1 , the utilized sensing at least for a part being performed within the NIR spectrum.
64 . The method of claim 1 , the utilized sensing at least for a part being performed within the SWIR spectrum.
65 . The method of claim 1 , the PDA having a sensitivity maximum at a wavelength longer than 3 microns and a sensitivity cut-off at a wavelength shorter than 5 microns.
66 . The method of claim 1 , the PDA having a sensitivity maximum at a wavelength shorter than 3 microns.
67 . The method of claim 66 , the PDA having a sensitivity cut-off at a wavelength shorter than 5 microns.
68 . The method of claim 66 , the PDA having a sensitivity cut-off at a wavelength between 1.4 μm and 1.65 μm.
69 . The method of claim 66 , the PDA having a sensitivity cut-off at a wavelength 1.65 μm and 1.8 μm.
70 . The method of claim 66 , the PDA having a sensitivity cut-off at a wavelength between 1.8 μm and 2.5 μm.
71 . The method of claim 1 , the PDA having a sensitivity maximum at a wavelength longer than 0.75 microns.
72 . The method of claim 1 , the PDA having a region of a predominant sensitivity fully within the NIR/SWIR range, said region being a region where the sensitivity is higher than 20% of a maximum PDA's sensitivity.
73 . The method of claim 72 , wherein the predominant sensitivity is higher than 35% of a maximum PDA's sensitivity.
74 . The method of claim 72 , wherein the predominant sensitivity is higher than 50% of the maximum PDA's sensitivity.
75 . The method of claim 72 , wherein the predominant sensitivity is higher than 70% of a maximum PDA's sensitivity.
76 - 85 . (canceled)
86 . The method of claim 1 , the sensing being substantially within a range of low atmospheric light transmission at least partially including the trough situated around 1.15 μm (micron).
87 . The method of claim 1 , the sensing being substantially within a range of low atmospheric light transmission at least partially including a trough extending from 1.34 μm to 1.50 μm.
88 . The method of claim 1 , the sensing being substantially within a range of low atmospheric light transmission at least partially including a trough extending from 1.80 μm to 2.00 μm.
89 . The method of claim 1 , the sensing being substantially within a range of low atmospheric light transmission at least partially including a trough extending from 2.50 μm to 2.90 μm.
90 . The method of claim 1 , the PDA being a CMOS PDA.
91 . The method of claim 1 , the PDA being an intracavity PDA.
92 . The method of claim 1 , an integration time of the sensing being between 10 −2 s and 5.0·10 −3 s.
93 . The method of claim 1 , an integration time of the sensing being between 5.0·10 −3 s and 2.0·10 −3 s.
94 . The method of claim 1 , an integration time of the sensing being between 2.0·10 −3 s and 5.0·10 −4 s.
95 . The method of 1 , an integration time of the sensing being between 5.0·10 −4 s and 10 −4 s.
96 . (canceled)
97 . A device for use in detection of a muzzle flash event, the device comprising a Photo Detector Array (PDA), sensitive in at least a portion of the NIR and SWIR spectrum, and a filter of electromagnetic radiation selectively passing in said portion a spectral range of low atmospheric transmission, the PDA having an integration time shorter than a duration of the muzzle flash event.
98 . The of claim 7 , wherein said integration time is shorter than 10 −2 s.
99 - 163 . (canceled)
164 . The device of claim 97 , the PDA at least partially being sensitive within the NIR spectrum.
165 . The device of any one of claim 97 , the PDA at least partially being sensitive within the SWIR spectrum.
166 . The device of any one of claim 97 , the PDA having a sensitivity maximum at a wavelength longer than 3 microns and a sensitivity cut-off at a wavelength shorter than 5 microns.
167 . The device of claim 97 , the PDA having a sensitivity maximum at a wavelength shorter than 3 microns.
168 . The device of claim 167 , the PDA having a sensitivity cut-off at a wavelength shorter than 5 microns.
169 . The device of claim 168 , the PDA having a sensitivity cut-off at a wavelength between 1.4 μm and 1.65 μm.
170 . The device of claim 168 , the PDA having a sensitivity cut-off at a wavelength 1.65 μm and 1.8 μm.
171 . The device of claim 168 , the PDA having a sensitivity cut-off at a wavelength between 1.8 μm and 2.5 μm.
172 . The device of any one of claim 97 , the PDA having a sensitivity maximum at a wavelength longer than 0.75 microns.
173 . The device of claim 97 , the PDA having a region of a predominant sensitivity fully within the NIR/SWIR range, said region being a region where the sensitivity is higher than 20% of a maximum PDA's sensitivity.
174 . The device of claim 173 , wherein the predominant sensitivity is higher than 35% of a maximum PDA's sensitivity.
175 . The device of claim 173 , wherein the predominant sensitivity is higher than 50% of the maximum PDA's sensitivity.
176 . The device of claim 173 , wherein the predominant sensitivity is higher than 70% of a maximum PDA's sensitivity.
177 - 186 . (canceled)
187 . The device of claim 97 , the device adapted to sense electromagnetic radiation substantially within a range of low atmospheric light transmission at least partially including the trough situated around 1.15 μm (micron).
188 . The device of claim 97 , the device adapted to sense electromagnetic radiation substantially within a range of low atmospheric light transmission at least partially including a trough extending from 1.34 μm to 1.50 μm.
189 . The device of claim 97 , the device adapted to sense electromagnetic radiation substantially within a range of low atmospheric light transmission at least partially including a trough extending from 1.80 μm to 2.00 μm.
190 . The device of claim 97 , the device adapted to sense electromagnetic radiation substantially within a range of low atmospheric light transmission at least partially including a trough extending from 2.50 μm to 2.90 μm.
191 . The device of claim 97 , the PDA being a CMOS PDA.
192 . The device of claim 97 , the PDA being an intracavity PDA.
193 . The device of claim 97 , an integration time of the PDA sensing being between 10 −2 s and 5.0·10 −3 s.
194 . The device of claim 97 , an integration time of the PDA sensing being between 5.0·10 −3 s and 2.0·10 −3 s.
195 . The device of claim 97 , an integration time of the PDA sensing being between 2.0·10 −3 s and 5.0·10 −4 s.
196 . The device of claim 97 , an integration time of the PDA sensing being between 5.0·10 −4 s and 10 −4 s.
197 . (canceled)
198 . (canceled)
199 . (canceled)
200 . The device of claim 97 , wherein said filter passes less than 50% of energy of wavelengths being outside said spectral range of low atmospheric transmission and sensed by the PDA.
201 . The device of claim 97 , wherein said filter passes less than 25% of energy of wavelengths being outside said spectral range of low atmospheric transmission and sensed by the PDA.
202 . The device of claim 97 , wherein said filter passes less than 10% of energy of wavelengths being outside said spectral range of low atmospheric transmission and sensed by the PDA.
203 . The device of claim 97 , wherein said filter passes less than 2% of energy of wavelengths being outside said spectral range of low atmospheric transmission and sensed by the PDA.
204 . The device of claim 200 having for at least one wavelength of said spectral range a sensitivity between 50% and 75% of the sensitivity of the PDA.
205 . The device of claim 200 having for at least one wavelength of said spectral range a sensitivity larger than 75% of the sensitivity of the PDA.
206 . A processing unit for use in detection of a muzzle flash event, said processing unit being adapted to process pixel signals originating from a PDA and to generate substantially likelihoods of muzzle flash detection for pixels of the PDA, the processing unit comprising a multiplexer dividing the pixel signals between at least two branches.
207 - 209 . (canceled)