Method and system for detecting an individual by means of passive infrared sensors

• US 8,514,280 B2
• Filed: 11/22/2006
• Issued: 08/20/2013
• Est. Priority Date: 12/19/2005
• Status: Active Grant

• Current Assignee: Joseph Zisa
• Original Assignee: Hymatom SA, Joseph Zisa
• Inventors: Taillade, Bernard, Zisa, Joseph
• Primary Examiner(s): Nguyen, Dustin
• Application Number:
  US12/093,616
• Publication Number:
  US 20090219388A1
• Time in Patent Office: 2,463 Days
• Field of Search: 340/426.26, 340/522, 340/572.1, 356/610, 396/51, 382/181, 382/224
• US Class Current: 348/143
• CPC Class Codes: G08B 13/19 using infrared-radiation detection systems G08B13/194 takes precedence
• 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

The invention relates to a method and a system for detecting an individual in a given observation zone by means of N passive infrared sensors (1) each consisting of an optical device (2) provided with a matrix of cells focusing the infrared energy (IR) received onto a single pyro-electric component (3) linked to a calculation unit (4) able to interpret the information received. The device according to the invention is characterized in that it consists, in order to detect an individual in the observation zone, in employing a limited number of N similar infrared sensors (1) centered on the same observation zone, each provided with 2^N−1 cells (2C), and hence beams (F), which for each of the latter are masked, according to a different combination in such a way as to provide the calculation unit with the information enabling the individual to be located in terms of position and displacement.

Claims

1. A method for detection of a person in a given observation zone, by coding the visual field, the method comprising:

arranging N passive infrared sensors including each a single pyro-electric component and an optical device including a matrix of cells, of lens or mirror type, defining 2^N distinct beams according to a well-defined horizontal and vertical distribution and focusing the received infrared energy, which is emitted by a person traversing the observation zone, onto the single pyro-electric component,

each matrix of 2^N cells being masked according to a different combination arranged in order to pick up corresponding beams of the observation zone,

each pyro-electric component transmitting, to a calculation unit, 2^N−

1 binary data of N bits each in order to locate the person in terms of position and movement.

2. A method according to claim 1 further including slightly angularly shifting the cells of the various optical devices in order to increase the accuracy of the localization of the person.

3. A method according to claim 1 further including coupling a fixed camera, focused on the observation zone, to the calculation unit, in order to confirm the position and the movement of the person by an analysis of the image in the one of the cells of the observation zone.

4. A method according to claim 1 further including the step, performed by the calculation unit of, of driving a mobile camera to the one of the cells of the observation zone, in order to confirm the position of the person.

5. A method according to claim 1 further including using optical devices, the masking of the cells of which being programmable.

6. A system for the implementation of the method according to claim 1, characterized in the optical devices are chosen from a Fresnel lens of injected plastic, a set of juxtaposed mirrors or a liquid crystal screen including a matrix of programmable cells.

7. A system according to claim 6 characterized in that the optical focus device is constituted by optical lenses specific and necessary to coverage zones of the N sensors and of which the surface of each lens is double in order to double the sensitivity.

8. A system according to claim 6 characterized in that it includes sensors, a fixed camera and/or a mobile camera equipped with a zoom and a calculation unit interpreting the data received from the sensors and controlling the cameras.

9. A method for detection of a person, the method comprising:

arranging N passive infrared sensors each including an optical device, each optical device including a matrix of cells, of the lens or mirror type, arranged in order to pick up a plurality of beams according to a well-defined horizontal distribution and distribution vertical,

the method further including the steps, performed by each infrared sensor, of;

receiving infrared energy of the person traversing an observation zone;

focusing the received infrared energy onto a single pyro-electric component, via the optical device; and

sending data from the single pyro-electric component to a calculation unit, the optical devices having vertical beams covering an angle up to 90 degrees,

the method further including the steps, performed in the calculation unit, of;

receiving the data sent by the infrared sensors;

processing the received data in order to locate the person to be in one of 2^N−

1 cells of the observation zone.

10. A method according to claim 9 further including the step, performed by the calculation unit of, of driving a mobile camera to the one of the cells of the observation zone, in order to confirm the position of the person.