Thermally sensitive array device for presence detection around automatic doors

• US 20060087430A1
• Filed: 07/20/2005
• Published: 04/27/2006
• Est. Priority Date: 07/22/2004
• Status: Active Grant

• Current Assignee: BEA (Halma PLC)
• Original Assignee: BEA SA PARC Scientifique Du Sart-Tilman
• Inventors: Zambon, Alain
• Granted Patent: US 7,362,224 B2
• Time in Patent Office: Days
• US Class Current: 340/567
• CPC Class Codes: E05F 15/608 for revolving wings
• CPC Class Codes: E05F 15/73 responsive to movement or presence of persons or objects
• CPC Class Codes: E05Y 2800/414 against high or low temperatures
• CPC Class Codes: E05Y 2900/132 Doors
• CPC Class Codes: G01J 5/14 Electrical features thereof
• CPC Class Codes: G01K 17/003 for measuring the power of light beams, e.g. laser beams

Abstract

The present invention relates to a thermally sensitive array device for detecting a presence of a target object in a surveillance area. The device comprises a plurality of at least two thermally sensitive sensors provided in an array arrangement, each thermally sensitive sensor being associated with one of a corresponding plurality of at least two surveillance spots comprised in the surveillance area. Each thermally sensitive sensor comprises a sensitive element adapted to absorb a portion of thermal infrared radiation emitted from one of said plurality of targets located inside the surveillance cone corresponding to the thermally sensitve sensor. Thermally sensitive sensor can be thermopiles, Bolometers or any other type. Electronic circuits in each thermally sensitive sensor are adapted to measure a signal generated in the thermally sensitive sensor as a consequence of the temperatures of the target. The device may further comprise electric multiplex measurement circuitry electrically coupled to the different sensors. The device is adapted to perform differential measurements between selectable pairs of thermopile sensors, of the temperatures prevailing in the corresponding surveillance cones.

Claims

1. A thermally sensitive array device (80) for detecting a presence of an object in a surveillance area (56), comprising:

a plurality of at least two thermally sensitive sensors (10-i) provided in an array arrangement, each thermally sensitive sensor (10-i) being associated with one of a corresponding plurality of at least two surveillance cones (50-i) comprised in the surveillance area (56), and

each thermally sensitive sensor is further adapted to absorb a portion of thermal infrared radiation emitted from the corresponding associated one of said plurality of surveillance cones (50-i), wherein each thermally sensitive sensor (10-i) further comprises an electronic circuit that is electrically coupled to the sensor for measuring a signal (V_t-i) generated in the thermally sensitive sensor (12-i) as a consequence of a target temperature.

2. The device of claim 1, characterized in that it comprises thermopile sensors or Bolometers sensors.

3. The device of claim 1, wherein the signal (Vt-i) is a voltage generated between first and second contacts (15-i, 19-i) of one of the at least two thermally sensitive sensors (10-i).

4. The device of claim 1, further comprising pre/amplifying circuitry adapted to measure the plurality of voltages (Vt-i) produced by the plurality of thermally sensitive sensors (10-i) and multiplex circuitry adapted to provide a plurality of varying electrical signals corresponding to each thermally sensitive sensor (10-i) and indicative of temperatures prevailing in the corresponding surveillance cones (50-i).

5. The device of claim 1, further comprising a package (42) adapted to accommodate therein said plurality of thermally sensitive sensors (10-i), a plurality of optical elements (44-i), each optical element (44-i) being adapted to image the portion of infrared radiation emitted from the corresponding surveillance spot (52-i) onto a first source element (14-i) of the corresponding thermally sensitive sensor (10-i).

6. The device of claim 5, wherein the optical elements (44-i) are lenses adapted to transmit thermal infrared radiation.

7. The device of claim 1, wherein the array arrangement is a linear array.

8. The device of claim 1, wherein the array arrangement is a two-dimensional array.

9. The device of claim 1, wherein at least one sensor element (18-i) is adapted to be put at a variably selectable reference temperature.

10. The device of claim 1, further comprising a plurality of heating elements (22-i) corresponding to the plurality of thermally sensitive sensors (10-i), each heating element (22-i) being provided near and adapted to heat a sensitive element (18-i) so as to attain a variably selectable reference temperature used for the monitoring of the sensor detection performances.

11. The device of claim 10, wherein the heating function can be performed by the sensor itself if a current is generated through the sensor.

12. The device of claim 1, further comprising a supplementary sensor adapted to detect the presence and/or the motion of a target object in a supplementary surveillance area (54-1, 54-2), the supplementary sensor being of a different type than the thermally sensitive sensor (10-i).

13. The device of claim 12, wherein the supplementary sensor is one of a microwave radar sensor, a microwave Doppler sensor, an active infrared sensor or a pyro-electric sensor.

14. The device of claim 1, wherein the plurality of thermally sensitive sensors (10-i) is fabricated on a common substrate (40).

15. The device of claim 14, wherein the substrate is a silicon substrate and the thermally sensitive sensors are fabricated using silicon integration technology, preferably CMOS integration technology.

16. A door sensor device adapted to detect the presence and/or motion of a target object in a surveillance area extending in and/or near a door threshold, wherein the door comprises at least one movable door element (64;

66;

68) adapted to open and close a door opening, the device comprising;

at least one thermally sensitive array device (80) according to claims claim 1 corresponding to the at least one door element (64;

66, 68),

wherein the plurality of surveillance cones (50-i) of the at least one thermally sensitive array device (80) are arranged in a linear array arrangement that extends substantially parallel to the corresponding door element (64;

66;

68).

17. The door sensor device of claim 16, wherein the surveillance cones extend on both sides of a corresponding moving door element (64, 66, 68).

18. The door sensor device of claim 16, wherein interactions of the surveillance cones (50-i) generate surveillance spots which are located on a ground or at any height above the ground.

19. The door sensor device according to claim 16, wherein when the door comprises a sliding door arrangement comprising one or more moving door elements (64-1, 64-2) adapted to slide in a plane that is substantially parallel to the door opening, the linear array arrangement of surveillance spots of the at least one thermally sensitive array sensor extend substantially across and along the moving door element or the threshold of the door.

20. The door sensor device according to claim 19 comprising two thermally sensitive array devices (80), wherein the linear array arrangements of surveillance spots (54-1i), (54-2i) corresponding to the two array device are located on opposite sides of the door threshold.

21. The door sensor device according to claim 16, wherein when the door comprises a swinging door arrangement comprising one or more swinging door elements (66), at least one thermally sensitive array device (80) is provided for each swinging door element (66), wherein the linear arrangements of surveillance spots corresponding to each thermally sensitive array device move with the corresponding swinging door element (66) such that they remain substantially parallel thereto.

22. The door sensor device according to claim 21, comprising two thermally sensitive array devices (80) associated with each swinging door element (66), the two corresponding linear array arrangement of surveillance spots (52-1i, 52-2i) being located on opposite sides of the swinging door element (66).

23. The door sensor device according to anyone of the claims claim 16, wherein when the door is a revolving door arrangement comprising plural revolving door elements (68-1, 68-2, 68-3, 68-4), at least one thermally sensitive array device (80) is provided for each revolving door element (68-1, 68-2, 68-3, 68-4), wherein the linear arrangements of the surveillance spots (52-i) move with the corresponding one of each revolving door elements (68-1, 68-2, 68-3, 68-4) such that they remain substantially parallel thereto.

24. The door sensor device according to claim 23, wherein the linear arrangements of surveillance spots are arranged on a side forward in the rotational revolving direction relative to the revolving door element (68-1, 68-2, 68-3, 68-4).

25. The door sensor device according to claim 23, comprising two thermally sensitive array devices (80) for each revolving door element (68-1, 68-2, 68-3, 68-4), the two corresponding linear array arrangements of surveillance spots (52-1i, 52-2i, 52-3i, 52-4i) of which are located on opposite sides of the corresponding one of each revolving door element (68-1, 68-2, 68-3, 68-4).

26. The door sensor device according to claim 16, further comprising at least one supplementary sensor adapted to detect the presence and/or motion of an object in at least one supplementary surveillance area (54-1, 54-2), the supplementary sensor being of a different type than a thermally sensitive sensor (10-i).

27. The device of claim 26, wherein the supplementary sensor is one of a microwave radar sensor, a microwave Doppler sensor, an active infrared or a pyro-electric sensor.