GUNSHOT DETECTION SYSTEM AND METHOD

• US 20110170798A1
• Filed: 07/22/2010
• Published: 07/14/2011
• Est. Priority Date: 01/23/2008
• Status: Abandoned Application

• Current Assignee: ELTA Systems Limited (Government of Israel)
• Original Assignee: ELTA Systems Limited (Government of Israel), Optigo Systems Ltd.
• Inventors: Tidhar, Gil
• Application Number:
  US12/841,289
• Publication Number:
  US 20110170798A1
• Time in Patent Office: Days
• US Class Current: 382/276
• CPC Class Codes: G01J 1/42 using electric radiation detectors optical or mechanical part G01J1/04; by comparison with a reference light or electric value G01J1/10
• CPC Class Codes: G01J 3/2803 using photoelectric array detector
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

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.

Claims

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.

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 μ

m and 1.65 μ

m.

69. The method of claim 66, the PDA having a sensitivity cut-off at a wavelength 1.65 μ

m and 1.8 μ

m.

70. The method of claim 66, the PDA having a sensitivity cut-off at a wavelength between 1.8 μ

m and 2.5 μ

m.

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.

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 μ

m (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 μ

m to 1.50 μ

m.

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 μ

m to 2.00 μ

m.

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 μ

m to 2.90 μ

m.

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<sup>−

3</sup> s.

93. The method of claim 1, an integration time of the sensing being between 5.0·

10<sup>−

3</sup> s and 2.0·

10<sup>−

3</sup> s.

94. The method of claim 1, an integration time of the sensing being between 2.0·

10<sup>−

3</sup> s and 5.0·

10<sup>−

4</sup> s.

3-62. -62. (canceled)

76-85. -85. (canceled)

95. The method of 1, an integration time of the sensing being between 5.0·

10<sup>−

4</sup> s and 10<sup>−

4</sup> 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.

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 μ

m and 1.65 μ

m.

170. The device of claim 168, the PDA having a sensitivity cut-off at a wavelength 1.65 μ

m and 1.8 μ

m.

171. The device of claim 168, the PDA having a sensitivity cut-off at a wavelength between 1.8 μ

m and 2.5 μ

m.

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.

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 μ

m (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 μ

m to 1.50 μ

m.

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 μ

m to 2.00 μ

m.

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 μ

m to 2.90 μ

m.

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<sup>−

3</sup> s.

194. The device of claim 97, an integration time of the PDA sensing being between 5.0·

10<sup>−

3</sup> s and 2.0·

10<sup>−

3</sup> s.

195. The device of claim 97, an integration time of the PDA sensing being between 2.0·

10<sup>−

3</sup> s and 5.0·

10<sup>−

4</sup> s.

196. The device of claim 97, an integration time of the PDA sensing being between 5.0·

10<sup>−

4</sup> s and 10<sup>−

4</sup> s.

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.

99-163. -163. (canceled)

177-186. -186. (canceled)

197. (canceled)

198. (canceled)

199. (canceled)

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. -209. (canceled)