WO2013060859A1 - Infrared presence detector for detecting a presence of an object in a surveillance area - Google Patents
Infrared presence detector for detecting a presence of an object in a surveillance area Download PDFInfo
- Publication number
- WO2013060859A1 WO2013060859A1 PCT/EP2012/071284 EP2012071284W WO2013060859A1 WO 2013060859 A1 WO2013060859 A1 WO 2013060859A1 EP 2012071284 W EP2012071284 W EP 2012071284W WO 2013060859 A1 WO2013060859 A1 WO 2013060859A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- value
- contrast
- sensor signal
- infrared radiation
- sensor
- Prior art date
Links
- 230000005855 radiation Effects 0.000 claims abstract description 61
- 238000001514 detection method Methods 0.000 claims abstract description 59
- 238000000034 method Methods 0.000 claims abstract description 36
- 238000012545 processing Methods 0.000 claims abstract description 32
- 238000012937 correction Methods 0.000 claims description 8
- 238000009529 body temperature measurement Methods 0.000 claims description 6
- 238000004891 communication Methods 0.000 claims description 4
- 230000008901 benefit Effects 0.000 description 17
- 230000004044 response Effects 0.000 description 10
- 230000006870 function Effects 0.000 description 9
- 238000005070 sampling Methods 0.000 description 8
- 230000033001 locomotion Effects 0.000 description 6
- 241000282412 Homo Species 0.000 description 5
- 239000004020 conductor Substances 0.000 description 5
- 230000035945 sensitivity Effects 0.000 description 4
- 230000003068 static effect Effects 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 230000001960 triggered effect Effects 0.000 description 3
- 238000003491 array Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000013598 vector Substances 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 230000005678 Seebeck effect Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000006399 behavior Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000012888 cubic function Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 238000012806 monitoring device Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- -1 polyethylene Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/0022—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiation of moving bodies
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/0022—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiation of moving bodies
- G01J5/0025—Living bodies
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/025—Interfacing a pyrometer to an external device or network; User interface
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/026—Control of working procedures of a pyrometer, other than calibration; Bandwidth calculation; Gain control
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/08—Optical arrangements
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/08—Optical arrangements
- G01J5/0806—Focusing or collimating elements, e.g. lenses or concave mirrors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/08—Optical arrangements
- G01J5/0846—Optical arrangements having multiple detectors for performing different types of detection, e.g. using radiometry and reflectometry channels
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/10—Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors
- G01J5/12—Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using thermoelectric elements, e.g. thermocouples
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/10—Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors
- G01J5/20—Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices
- G01J5/22—Electrical features thereof
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
- G08B13/189—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems
- G08B13/19—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using infrared-radiation detection systems
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
- G08B13/189—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems
- G08B13/194—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using image scanning and comparing systems
Definitions
- the present invention relates to the field of presence detection. More specifically it relates to the determination of the presence of objects in a region of interest by using a thermal radiation sensor.
- Presence or occupancy detection is used in systems that automatically take action when an object of interest, e.g. a person, is present in a region of interest, e.g. a surveillance area.
- a door e.g. a sliding door
- lights may be switched on when a person enters a room or is in the vicinity of the lights, lights may be switched off when no-one is in a room, or an alarm may be triggered when an intrusion is detected.
- detection may involve sensors for detecting infrared radiation emitted by these objects.
- Infrared detection may be carried out using compact and affordable technology, and has the advantage over other techniques, such as visual image recognition, acoustic sensing or ultrasonic detection, that warm-blooded living beings, such as humans, emit thermal radiation having a characteristic spectral distribution, e.g. a peak around 9.5 ⁇ for humans, and having considerable power, e.g. around 100 W for humans. Since infrared radiation is emitted by these warm-blooded living beings, detection does not require external lighting. Furthermore, many materials which are opaque or only allow limited transmission of light in the visual spectrum are transparent for infrared radiation.
- PIR sensors are commonly used to detect moving heat generating objects in a surveillance area.
- Such a PIR sensor transforms infrared energy, e.g. heat radiation, into an electrical signal, e.g. a voltage.
- the term passive in this instance means that the PIR sensor does not emit an infrared beam but merely passively accepts incoming infrared radiation.
- PIR sensors for detecting persons may have a wavelength sensitivity peak tuned to around 10 ⁇ , e.g. close to the 9.5 ⁇ , the peak wavelength of infrared radiation emitted by humans.
- Such a PIR sensor device for occupancy detection is disclosed in US 4,318,089.
- a prior art PIR sensor device for presence detection may comprise a pair of spaced apart infrared radiation sensing elements in an enclosure, such as a three-pin metal header package for semiconductor devices, e.g. a TO-5 package.
- the enclosure may further feature a transparent window in order to limit the radiation transmitted through the window into the enclosure to a suitable wavelength range, e.g. between 5 ⁇ and 15 ⁇ or between 7 ⁇ and 14 ⁇ .
- a transparent window may for example be manufactured from an appropriate material such as germanium, silicon or polyethylene.
- the pair of infrared radiation sensing elements may be pyroelectric elements, connected in a voltage bucking configuration, for example connected in anti-phase series, e.g. by an electrically connected pair of matched poles of both elements.
- Pyroelectric elements have a differential response; a temperature change induces a temporary voltage change over the element which will dissipate due to leakage current at constant temperature.
- a differential readout arrangement over two elements may additionally cancel out signals caused by vibration, ambient temperature changes or field- wide illumination, e.g. by sunlight.
- the enclosure comprising the pyroelectric elements may further comprise a sensitive field-effect transistor (FET) in order to read out the voltage over the pair of sensitive elements.
- the two sensitive elements in anti-phase series may for example be grounded on one terminal, and on the other terminal be connected to the gate of the FET and connected to a pull-down resistor.
- Fresnel lens or a multi-faceted parabolic mirror in order to project infrared radiation emitted by an object that generates heat, e.g. a person, onto the sensing elements.
- This focusing element is designed such that radiation emitted by a heat-generating object moving across the surveillance area, e.g. crossing the field of view of the detection device, is projected onto the sensing elements in an alternating manner, i.e. the element on which this radiation is concentrated switches repeatedly.
- an alternating current is generated on the output of the FET, which may be further amplified.
- the advantage of coupling the elements in a voltage bucking configuration, e.g. in anti-phase series, is that the sensor device becomes insensitive to the environment temperature.
- further filtering may condition the signal, e.g. to reduce aliasing, before sampling it with an analog-to-digital converter (ADC), usually at a low sampling rate, for example less than 10 Hz, e.g. 5 Hz.
- ADC analog-to-digital converter
- the sampling rate is typically quite low due to a low signal-to-noise ratio (SNR), e.g.
- the peaks of the filtered signal may be detected, which will trigger an event for a preset duration if it reached a certain level, for example a peak may trigger the switching on of a light or the opening of a door and the restarting of a timer which will switch off the light or close the door after a preset delay, which is usually user-controllable.
- PIR-based detection method may have disadvantages caused by the inherent differentiating behavior of the design.
- Such devices only get triggered when moving objects are detected in the surveillance area. For example, when persons stay longer motionless than a timer in a PIR-based sensor device for light switching allows, they might be surprised by the switching off of the light.
- PIR devices as known in the art often require a complex design, e.g. carefully designed Fresnel lenses, to be able to provide an indication of direction of movement of a detected object, e.g. direction of walking of a person.
- Automatic sliding doors that use PIR sensors to detect persons are therefore typically not arranged at the side-walls of hallways because of the many false alarms that may be triggered by people just passing by.
- a PIR-based device that is capable of providing an indication of the number of detected objects in a surveillance area, e.g. how many persons are present in a scene, poses further complications.
- the present invention provides a detection device for detecting a presence of an object in a surveillance area.
- the device comprises at least one infrared radiation sensing element adapted for generating a sensor signal related to a quantity of infrared radiation received from within the surveillance area; a processing unit adapted for obtaining said sensor signal, generating a contrast value by comparing the obtained sensor signal to a reference value, and determining the presence of the object by evaluating a condition on said contrast value; and an output means for outputting the determined presence of the object and/or a property derived therefrom.
- the processing unit is further adapted for adjusting the reference value such that negative feedback is applied to the contrast value.
- a device may detect objects which emit radiant heat, both when these objects remain static and when these objects are moving.
- a device may not be sensitive to immobile heat-emitting objects, such as heaters, while remaining sensitive to mobile heat-emitting objects, even when such objects remain immobile for a while.
- a device is provided that may replace conventional PIR-based detector devices in a detection system without requiring extensive redesign.
- a device that does not require a timer. It is an advantage of embodiments of the present invention that a device is provided that may be used in a wide range of settings without requiring adjustments of user- controllable parameters, such as sensitivity or timer settings.
- the processing unit may be adapted for generating a contrast value by subtracting a reference value from the sensor signal; determining the object as being present when said contrast value exceeds a predetermined first level; and adjusting the reference value such that negative feedback is applied to the contrast value by adding a predetermined fraction of the contrast value thereto when said contrast value is below a predetermined second level.
- a device is provided that is robust to nuisance objects, such as heaters or windows, while remaining sensitive to targeted heat-emitting objects such as people.
- a device may adapt to the presence of such nuisance objects in a dynamic and efficient manner, e.g. without requiring a calibration without targeted heat-emitting objects such as people present.
- the at least one infrared radiation sensing element may comprise at least one thermopile sensor.
- a device may detect both immobile and mobile objects which emit radiant heat.
- a detection device may further comprise an ambient temperature sensor.
- the processing unit may be further adapted for receiving a temperature signal from said ambient temperature sensor and for applying a temperature correction to said sensor signal or to said reference value taking into account the temperature signal.
- a detection device may be controlled by few parameters which are little sensitive to environmental conditions, e.g. that may not require tuning for use in a specific surveillance area.
- the at least one infrared radiation sensing element may comprise an array of infrared radiation sensing elements
- the processing unit may be adapted for receiving a plurality of sensor signals, each sensor signal being received from a corresponding infrared radiation sensing element of said array; providing a plurality of contrast values by element-by-element comparing the plurality of sensor signals to a plurality of reference values; determining the presence of the object by evaluating said condition on said plurality of contrast values; and adjusting the plurality of reference values element-by-element such that negative feedback is applied to the plurality of contrast values.
- a device may determine the direction of movement of one or multiple objects in a surveillance area, e.g. in order to improve efficiency when used in a control system for the opening of sliding doors.
- each infrared radiation sensing element of said array may be adapted for generating a sensor signal related to a quantity of infrared radiation received from within a corresponding sub- region of the surveillance area, and said output means may be adapted for outputting a count of contrast values in the plurality of contrast values which satisfy said condition and/or a property derived therefrom. It is an advantage of such embodiments of the present invention that a device may be provided that can perform counting, e.g. of persons in a room.
- a detection device may furthermore comprise at least one wireless communication module for transmitting information between said at least one infrared radiation sensing element, said processing unit, and/or said output means. It is an advantage of embodiments of the present invention that a device may be provided that may be easy to install, i.e. that requires few wired connections.
- the present invention provides a method for detecting a presence of an object in a surveillance area.
- the method comprises obtaining at least one sensor signal value related to a quantity of infrared radiation received from within the surveillance area; generating at least one contrast value by comparing the at least one sensor signal value to at least one reference value; and determining the presence of the object by evaluating a condition on said at least one contrast value.
- the method according to embodiments of the present invention furthermore comprises adjusting the at least one reference value such that negative feedback is applied to said at least one contrast value.
- said providing a contrast value may comprise subtracting the reference value from the sensor signal value, and determining the presence of the object may comprise evaluating whether said contrast value exceeds a predetermined first level.
- Said adjusting of the reference value may comprise adding a predetermined fraction of the contrast value thereto. Said adjusting of the reference value may be executed when a further condition on said contrast value is met.
- evaluating whether a further condition on said contrast value is met may comprise evaluating whether said contrast value is below a predetermined second level.
- a method according to embodiments of the present invention may furthermore comprise applying a temperature correction to said sensor signal value or to said reference value taking into account an ambient temperature measurement.
- FIG. 1 schematically shows a first embodiment of a detection device according to a first aspect of the present invention.
- FIG. 2 schematically illustrates an architecture of a thermopile sensor system according to embodiments of the present invention.
- FIG. 3 schematically shows a second embodiment of a detection device according to the first aspect of the present invention.
- FIG. 4 illustrates detection of an object by means of a detection device according to the second embodiment of the first aspect of the present invention.
- FIG. 5 illustrates exemplary method steps of a method according to a second aspect of the present invention.
- FIG. 6 illustrates skin temperature in relation to the warmth of the environment.
- FIG. 7 shows an exemplary response signal as function of time for a prior art detection device.
- FIG. 8 shows an exemplary response signal for a detection device according to embodiments of the present invention when one object of interest is present.
- FIG. 9 shows an exemplary response signal for a detection device according to embodiments of the present invention when no object of interest is present.
- thermopile refers to an electronic element for converting thermal energy into electrical energy, e.g. for generating a voltage difference indicative of a local temperature difference, e.g. substantially proportional to such temperature difference.
- a thermopile comprises a plurality of interconnected thermocouples, usually connected in series, which may for example each be obtained by stacking a number of layers of at least two different conductive materials such as metal alloys.
- a thermocouple if a temperature difference is applied to two junctions of two dissimilar conductors, a voltage which may be proportional to the temperature difference is generated by the Seebeck-effect.
- thermopile By combining multiple thermocouples in a series connection, a thermopile is obtained that amplifies the rather small voltage drop generated over a single thermocouple.
- a thermopile for infrared radiation detection may be formed on a semiconductor, e.g. silicon, chip. For example, an area of this chip may be etched away, leaving only a thin membrane, on which alternating layers of two different conductive materials may be deposited. Both types of conductors may have alternating junctions in the centre of the membrane and on the bulk of the semiconductor substrate. The central junctions, or hot junctions, at the centre of the membrane may then be covered by a suitable infrared absorbing layer. The junctions at the other extremities of the conductors form the cold junctions.
- the thermopile may be mounted on a TO or SMD header with a suitable filter cap, i.e. transparent for an infrared wavelength window of interest.
- the present invention relates to a detection device 10 for detecting presence or absence of an object 9 in a surveillance area 8.
- FIG. 1 shows an illustrative embodiment of a detection device 10 according to this first aspect.
- This detection device 10 comprises at least one infrared radiation sensing element 11, in the form of a thermopile sensor.
- This infrared radiation sensing element 11 is adapted for generating a sensor signal, i.e. an electrical output signal such as for example an output voltage, indicative of infrared radiation received from within the surveillance area 8.
- the detection device 10 may comprise a focusing element 7, e.g. a lens, for example a silicon lens, for focusing onto the sensing element 11 infrared radiation from within the surveillance area 8, e.g. from within a cone which projects onto the infrared radiation sensing element 11 through the focusing element 7.
- a focusing element 7 e.g. a lens, for example a silicon lens, for focusing onto the sensing element 11 infrared radiation from within the surveillance area 8, e.g. from within a cone which projects onto the infrared radiation sensing element 11 through the focusing element 7.
- the detection device 10 further comprises a processing unit 12, which is adapted for receiving the sensor signal from the sensing element 11.
- the sensor signal may be transferred over a signal wire as an analog electric signal from the infrared radiation sensing element 11 to the processing unit 12.
- the processing unit 12 may comprise an analog-to- digital (ADC) converter and a microprocessor or a digital computing device for carrying out the logical and arithmetic operations set forth further herein.
- ADC analog-to- digital
- the processing unit 12 may be adapted for analog signal processing, and as such in fact may carry out the described operations without an analog-to- digital conversion.
- the sensor signal may be transferred from the sensing element 11 to the processing unit 12 in a digital form, e.g. the signal may be converted into a digital signal by the sensing device and then transmitted, for example, over a bus such as an l 2 C bus.
- Such digitized signal may also be transmitted through wireless communication modules.
- the processing unit 12 is furthermore adapted for providing a contrast value by comparing the received sensor signal to a reference value.
- This contrast value may be a difference calculated by subtracting the reference value from the sensor signal, or may include a function, e.g. a cubic function, applied to this difference.
- the sensor signal may be represented by a digital sample, e.g. sampled by an ADC component at a sampling rate of, for example, less than 20 Hz, e.g.
- the pre-set default value B 0 may correspond to a sensor signal value which would be obtained for a sufficiently high temperature of the surveillance area 8, e.g. substantially higher than room temperature, for example 40 °C.
- the processing unit 12 is furthermore adapted for determining the presence or absence of the object 9 by evaluating a condition on the contrast value.
- This object 9 may for example be determined to be present when the contrast value exceeds a predetermined first level.
- a heat-emitting object 9 may be assumed to have a surface temperature higher than its environment, e.g. a person may have a surface temperature approximately between27°C and 33°C, for a room with ambient temperature between 15°C and 30°C.
- the reference value 6 U may be interpreted as an evolving background temperature correction, e.g. will be adjusted in the way discussed further below in order to follow changes in the observed sensor signal /, due to temperature changes of the environment and of nuisance objects in the field of view of the sensing element 11, i.e.
- the presence may be determined by checking whether the contrast value C, exceeds a predetermined first level Li (which optionally can be a function of the room temperature), for example a value corresponding to a difference in sensor signal value obtained for an observed temperature difference between 0.5°C and 10°C, e.g. 2°C.
- a predetermined first level Li which optionally can be a function of the room temperature
- This condition on the contrast value reflects an underlying assumption about the object 9 to be detected, e.g. a human presence is typically hotter than the room-temperature as seen in FIG. 6, taken from "Skin Temperature in Relation to the Warmth of the Environment", T. Bedford, The Journal of Hygiene, Vol. 35, No. 3, pp. 307— 317, Aug. 1935.
- this is a feature of the object to be detected and its environment, and may therefore be more robust than, for example, a timer and/or sensitivity setting of a state of the art PIR sensor.
- the detection device 10 comprises an output means 13 for outputting the determined presence of the object 9 and/or a property derived therefrom.
- the output means 13 may comprise a signal wire output, a digital bus interface, a wired or wireless network interface or other means of electronic communication.
- the output means 13 may also comprise a power output for driving a device connected thereto, for example an actuator, such as an actuator for opening and closing a door, an alarm or a light.
- the device 10 may communicate through the output means 13 a derived property, i.e. a signal different from the present status of object presence, but related thereto.
- a derived property may for example be a statistic, e.g. number of objects detected in a time window, or the elapsed time since a last detection.
- the processing unit 12 is furthermore adapted for adjusting the reference value such that negative feedback is applied to the contrast value.
- negative feedback may be provided by adding a predetermined fraction of the contrast value to the reference value.
- this negative feedback may be conditional, such that the negative feedback is only applied when the contrast value is below a predetermined second level.
- This negative feedback regime may adjust the contrast value C, over time in order to compensate for changes, e.g. a radiator in the field of view that is slowly heating up.
- a new reference value 6, may be provided by 6, ⁇ . ⁇ .
- the proportionality ratio ⁇ may reflect a learning rate, e.g. in a convex filter approach, and may, for example, have a value between 0.01 and 0.10, e.g. 0.05, for a sampling rate of 1 Hz. This adjustment ma be carried out conditionally, e.g.
- the predetermined second level ⁇ may have a value smaller than the predetermined first level, e.g. a value corresponding to a sensor signal value which would be obtained for a temperature difference of between 0.1 and 2°C/s, e.g. below 1 °C/s, for example 0.2 °C/s.
- the detection device 10 may comprise an ambient temperature sensor 15.
- the processing unit 12 may be adapted for receiving a temperature signal from this ambient temperature sensor 15 and for applying a temperature correction to the sensor signal /, or to the pre-determined reference value 6, taking into account the temperature signal.
- the sensor signal /, the contrast value C, and the reference value 6, may all be normalized to a temperature scale, e.g. in °C, using the ambient temperature sensor reading T;.
- the processing unit 12 may perform following operations repeatedly:
- the contrast value in this example is calculated by a signed function, in order to generate a presence signal for objects which are hotter by a predetermined margin L than a background level.
- the second threshold ⁇ which may typically be smaller than L, adjusts a background reference level when a signal colder than the background is observed, or a signal which is hotter, but does not exceed the second threshold ⁇ .
- the ambient temperature measurements may be used to further calibrate the background signal through time in varying circumstances, thus providing normalized contrast values. This may increase robustness, i.e. the condition for presence determination and the condition for conditional negative feedback correction may be defined in units which are less sensitive to environmental conditions.
- FIG. 2 schematically illustrates the architecture of a thermopile sensor system 10 according to embodiments of the present invention, comprising at least one I radiation sensing element 11, e.g. a thermopile array.
- the signals of the radiation sensing element 11 are amplified in an amplifier 28 and sent as sensor signals I to a background subtraction unit 29 together with temperature information T from the room temperature.
- the background subtraction unit 29 updates the background signal BG and reports an event E when the sensor system 10 detects presence of a living being.
- the background subtraction unit 29 implements a background/trend subtraction function, taking into account the knowledge that has been obtained about both the detected object 9 and the environment:
- the at least one infrared radiation sensing element 11 may comprise at least two infrared radiation sensing elements 11.
- the at least one infrared radiation sensing element 11 may comprise an array 18 of infrared radiation sensing elements, e.g. infrared radiation sensing elements in a regularly interspaced array, for example a one-dimensional array, e.g. an array of 8x1 elements, or a two-dimensional array, e.g. an array of 8x8 elements.
- Each infrared radiation sensing element 11 of the array 18 may be adapted for generating a sensor signal related to a quantity of infrared radiation received from within a corresponding sub-region 17 of the surveillance area 8.Thus the surveillance area 8 may be covered by a plurality of sub-regions 17, e.g. cones, from which infrared light is projected onto the respective sensing elements 11.
- the array 18 may be a thermopile sensor array, such as a thermopile sensor array on an integrated circuit.
- a thermopile sensor array may comprise a set of remote temperature sensing elements, covering a joint viewing angle. Next to the temperature sensing elements, they may also have an accurate on-board means for temperature measurement of the sensor itself, e.g. a thermistor.
- Thermopile arrays may detect living beings, e.g. people, not only in motion, but also when they are static. Also, such arrays may be used to determine in which direction living beings are moving.
- a sensor system 10 also comprises a processing unit 12.
- the processing unit 12 may further be adapted for determining the presence of the object 9 by evaluating the condition on the plurality of contrast values: vector components associated with the
- Li can be a function of the room temperature measurement.
- the I, BG and E signals as introduced with reference to FIG. 2 in this embodiment are implemented as vectors, with the elements connected to the elements of the thermopile array sensor 11. In this way the presence of a living being can be deducted relative to the angle of the sensor, as shown in FIG. 4.
- the samples I and T are sampled in a repetitive way, for example once per second.
- the output means 13 may then communicate a presence, e.g. E to a connected device or a user.
- the output means may also provide a related property, such as a count of persons present in a room, for example by counting the number of peaks in C ; .
- the output means 13 may for example provide an indication of the direction in which objects are moving, for example by comparing a stored value Ej_i or Cj_i to the current value Ej or Cj.
- the processing unit 12 may further be adapted for adjusting the plurality of reference values element-by-element such that ne ative feedback is applied to the plurality of contrast values.
- B. .
- an actuator may be driven, such as an actuator for opening or closing a door, or actuating an alarm or a light.
- This may for example be used in hospitals or elderly care, where, if one or more dedicated sensing elements (e.g. the middle sensor element in FIG. 3) deliver a presence signal, this means a patient is in a particular position, e.g. in bed or in the sofa, while if other sensing elements (e.g. the sensor elements left or right from the middle sensor element in FIG. 3) deliver a presence signal, this means the patient may have fallen or is walking around.
- Such detection by the "other" sensing elements might trigger an alarm.
- the present invention provides in a method 20 for detecting a presence of an object 9 in a surveillance area 8.
- a method 20 is illustrated in FIG. 5.
- a method 20 according to the second aspect of the present invention may be carried out by a device according the first aspect of the present invention described hereinabove.
- the method 20 may be implemented in software, e.g. for executing on a microprocessor, such as a microprocessor forming part of the processing unit 12.
- the method 20 may be implemented through hardware design, or may be implemented as a combination of hard- and software.
- This method 20 comprises obtaining 21 a sensor signal value related to a quantity of infrared radiation received from within the surveillance area 8, for example a sensor signal value represented by at least one sensor signal generated by at least one infrared radiation sensing element 11.
- the method 20 further comprises generating 22 at least one contrast value by comparing the obtained at least one sensor signal values to at least one reference value. This may comprise subtracting the at least one reference value from the at least one sensor signal value.
- the method 20 further comprises determining 23 the presence of the object 9 by evaluating a condition on said generated at least one contrast value.
- This determining 23 may comprise evaluating whether the generated at least one contrast value exceeds a predetermined first level.
- the method 20 furthermore comprises adjusting 24 the reference value such that negative feedback is applied to said contrast value.
- This adjusting 24 may comprise adding a predetermined fraction of the generated at least one contrast value thereto.
- this adjusting 24 may be executed when a further condition on the contrast value is met, for example when the contrast value is below a predetermined second level.
- the method 20 may comprise applying 25 a temperature correction to the at least one sensor signal value or to the reference value, taking into account an ambient temperature measurement.
- At least one sensor signal value in particular embodiments may comprise obtaining a plurality of sensor signal values, each sensor signal value being related to a quantity of infrared radiation received from within a corresponding sub-region 17 of the surveillance area 8.
- Providing a contrast value 22 may comprises providing a plurality of contrast values by element-by-element comparing the plurality of sensor signal values to a plurality of reference values.
- Determining 23 the presence of the object 9 may comprise evaluating the condition on the plurality of contrast values.
- Adjusting 24 the reference value may comprise adjusting the plurality of reference values element-by-element such that negative feedback is applied to each of the plurality of contrast values.
- Embodiments of the present invention may provide accurate and efficient means and methods for the detection of living beings such as humans in a typical room-temperature environment.
- the present invention not being limited in any way thereby, principles of detection of heat-generating objects, such as human subjects, according to embodiments of the present invention may be explained by the following considerations.
- a background subtraction i.e. a trend removal, may be performed in accordance with embodiments of the present invention on sensor data by taking into account specific knowledge of the object to be detected and the environment.
- FIG. 7 a response curve is shown which was obtained from a PIR sensor with Fresnel lens as known in the art.
- the response curve shows the PIR response voltage as function of time.
- the conventional PIR sensor was directed towards a space with a chair. A person entered the space at a first time instance 71, sat on the chair over an extended time interval 73, and left again at a second time instance 72.
- the PIR sensor reacts in a differential manner, showing heavy fluctuations on its output when it detects a moving person, e.g. near the first 71 and second 72 time instance, but not when the person is sitting down quietly, e.g. over the time interval 73.
- An exemplary threshold level 74 is indicated on FIG. 7, which would be suitable for indicating the presence of the moving person.
- detecting the static person is not possible using a similar threshold level due to the differential nature of the PIR sensor.
- a detection device comprising eight thermopile sensor elements, can detect the static person as shown in FIG. 8, in which the output value per sensor element is shown graphically and numerically.
- FIG. 8 shows the response obtained by the detection device according to embodiments of the present invention at a moment during the time interval 73 as shown in FIG. 7.
- the high intensity response of one pixel 81 corresponds with the person sitting down.
- FIG. 9 shows the response obtained by the same device at a moment prior to the first time instance 71, thus before the person entered the room.
- the absence of the person corresponds to the absence of elevated pixel values.
- this detection device can just as well detect moving persons in the space.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Engineering & Computer Science (AREA)
- Human Computer Interaction (AREA)
- Geophysics And Detection Of Objects (AREA)
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
- Radiation Pyrometers (AREA)
- Burglar Alarm Systems (AREA)
Abstract
Description
Claims
Priority Applications (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ES12775721.9T ES2572680T3 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector to detect the presence of an object in a surveillance area |
EP12775721.9A EP2776802B1 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector for detecting a presence of an object in a surveillance area |
KR1020147010899A KR101947214B1 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector for detecting a presence of an object in a surveillance area |
RU2014121490A RU2616569C2 (en) | 2011-10-28 | 2012-10-26 | Infrared detector for object presence in surveillance zone detecting |
JP2014537636A JP6077553B2 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector for detecting the presence of an object in a surveillance area |
DK12775721.9T DK2776802T3 (en) | 2011-10-28 | 2012-10-26 | Infrared presence sensor for detection of existence of an object in a monitoring area |
US14/350,686 US9140609B2 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector for detecting a presence of an object in a surveillance area |
CN201280053140.4A CN104040310B (en) | 2011-10-28 | 2012-10-26 | For detecting the infrared Detection of Existence device of object existence in monitor area |
SI201230601A SI2776802T1 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector for detecting a presence of an object in a surveillance area |
HRP20160690TT HRP20160690T1 (en) | 2011-10-28 | 2016-06-16 | Infrared presence detector for detecting a presence of an object in a surveillance area |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP11187208 | 2011-10-28 | ||
EP11187208.1 | 2011-10-28 | ||
US201161553457P | 2011-10-31 | 2011-10-31 | |
US61/553,457 | 2011-10-31 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2013060859A1 true WO2013060859A1 (en) | 2013-05-02 |
Family
ID=48167156
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2012/071284 WO2013060859A1 (en) | 2011-10-28 | 2012-10-26 | Infrared presence detector for detecting a presence of an object in a surveillance area |
Country Status (14)
Country | Link |
---|---|
US (1) | US9140609B2 (en) |
EP (1) | EP2776802B1 (en) |
JP (1) | JP6077553B2 (en) |
KR (1) | KR101947214B1 (en) |
CN (1) | CN104040310B (en) |
CY (1) | CY1117422T1 (en) |
DK (1) | DK2776802T3 (en) |
ES (1) | ES2572680T3 (en) |
HR (1) | HRP20160690T1 (en) |
HU (1) | HUE028354T2 (en) |
PL (1) | PL2776802T3 (en) |
RU (1) | RU2616569C2 (en) |
SI (1) | SI2776802T1 (en) |
WO (1) | WO2013060859A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103815912A (en) * | 2014-01-26 | 2014-05-28 | 大连大学 | Real-time monitoring method for falling behaviors of old people living alone on basis of thermal infrared sensor array |
US9140794B2 (en) | 2013-09-11 | 2015-09-22 | Google Technology Holdings LLC | Electronic device and method for detecting presence |
CN112005242A (en) * | 2018-05-18 | 2020-11-27 | 易希提卫生与保健公司 | Presence and absence detection |
WO2021130034A1 (en) * | 2019-12-26 | 2021-07-01 | Signify Holding B.V. | Systems and methods for fusing data from single pixel thermopiles and passive infrared sensors for counting occupants in open offices |
US11250683B2 (en) | 2016-04-22 | 2022-02-15 | Maricare Oy | Sensor and system for monitoring |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10015453B2 (en) * | 2015-08-03 | 2018-07-03 | Michael T. Hobbs | Tunnel camera system |
EP3417432B1 (en) * | 2016-02-17 | 2021-05-26 | Carrier Corporation | Pyroelectric presence identification system |
US11079318B2 (en) * | 2016-03-10 | 2021-08-03 | Todos Technologies Ltd. | Gas sensing device and a method for sensing gas |
CN107230317A (en) * | 2016-03-25 | 2017-10-03 | 深圳富泰宏精密工业有限公司 | Abnormal behaviour monitoring system and method |
CN107340062A (en) * | 2016-05-03 | 2017-11-10 | 众智光电科技股份有限公司 | Temperature-sensing device and air-conditioning system |
CN107588857A (en) * | 2016-07-06 | 2018-01-16 | 众智光电科技股份有限公司 | Infrared ray position sensing apparatus |
CN106441596B (en) * | 2016-08-04 | 2019-03-26 | 深圳通感微电子有限公司 | Array infrared thermopile sensing device and method for sensing |
CN106524393A (en) * | 2016-09-29 | 2017-03-22 | 杭州鸿雁电器有限公司 | Human body temperature induction control system and controller |
GB2558608B (en) * | 2017-01-10 | 2020-05-06 | Workplace Fabric Ltd | Determining presence and absence |
JP2019015671A (en) * | 2017-07-10 | 2019-01-31 | 旭化成エレクトロニクス株式会社 | Program, computer-readable medium, terminal device, and estimating device |
JP7266274B2 (en) * | 2018-09-12 | 2023-04-28 | オプテックス株式会社 | Security sensor device |
KR102388782B1 (en) | 2019-12-05 | 2022-04-20 | 부산대학교 산학협력단 | System and Method for Deep Learning Based Object Detection Using PIR Sensor |
SE544639C2 (en) * | 2020-04-14 | 2022-10-04 | Jondetech Sensors Ab Publ | Method and system for determining the presence of a person to wake up a device |
CN111857154B (en) * | 2020-08-02 | 2022-03-04 | 珠海一微半导体股份有限公司 | Robot calibration detection method, chip and robot |
KR20230124389A (en) | 2022-02-18 | 2023-08-25 | 주식회사 호서텔넷 | Device for monitoring absence of human body using sensors, and method thereof |
CN115063940B (en) * | 2022-06-06 | 2024-02-09 | 中国银行股份有限公司 | Risk monitoring method and device, storage medium and electronic equipment |
CN117649734B (en) * | 2024-01-29 | 2024-04-12 | 湖南力研光电科技有限公司 | Intelligent security monitoring method and system based on multidimensional sensor |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4318089A (en) | 1980-03-24 | 1982-03-02 | David Frankel | Infrared detector system |
US4849737A (en) | 1986-11-26 | 1989-07-18 | Matsushita Electric Works, Ltd. | Person-number detecting system |
USRE34789E (en) * | 1985-04-17 | 1994-11-15 | Thermoscan Inc. | Infrared electronic thermometer and method for measuring temperature |
US5555512A (en) * | 1993-08-19 | 1996-09-10 | Matsushita Electric Industrial Co., Ltd. | Picture processing apparatus for processing infrared pictures obtained with an infrared ray sensor and applied apparatus utilizing the picture processing apparatus |
WO1998047118A1 (en) * | 1997-04-14 | 1998-10-22 | Koninklijke Philips Electronics N.V. | Video motion detector with global insensitivity |
US20070110181A1 (en) * | 2005-11-16 | 2007-05-17 | Honeywell International, Inc. | Multi-frequency wireless transmitter |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0663851B2 (en) * | 1985-04-17 | 1994-08-22 | サーモスキャン インコーポレーテッド | Infrared thermometer |
JPH06100660B2 (en) * | 1986-11-26 | 1994-12-12 | 松下電工株式会社 | People detection device |
JPH06100661B2 (en) * | 1986-11-26 | 1994-12-12 | 松下電工株式会社 | People detection device |
JPH0727551B2 (en) * | 1987-04-24 | 1995-03-29 | 松下電工株式会社 | People detection device |
JP2552270B2 (en) * | 1986-11-26 | 1996-11-06 | 松下電工株式会社 | Person detection device |
JPS63188772U (en) * | 1987-05-26 | 1988-12-05 | ||
JP2978374B2 (en) * | 1992-08-21 | 1999-11-15 | 松下電器産業株式会社 | Image processing device, image processing method, and control device for air conditioner |
JP3403246B2 (en) * | 1994-06-10 | 2003-05-06 | キング通信工業株式会社 | Passive infrared detector |
JPH08178750A (en) * | 1994-12-26 | 1996-07-12 | Murata Mfg Co Ltd | Infrared array sensor |
KR0166870B1 (en) * | 1995-07-13 | 1999-03-20 | 구자홍 | Decision apparatus of human's displacement by using ray sensor |
US20030027774A1 (en) | 1999-03-18 | 2003-02-06 | Ronald C. Hendrickson | Tuberculosis antigens and methods of use therefor |
WO2005024746A1 (en) * | 2003-09-08 | 2005-03-17 | Optex Co., Ltd. | Sensor-camera-ganged intrusion detecting apparatus |
RU2321068C1 (en) * | 2007-02-06 | 2008-03-27 | Общество с ограниченной ответственностью "АЛЬТОНИКА" (ООО "АЛЬТОНИКА") | Method for video control and access management |
-
2012
- 2012-10-26 CN CN201280053140.4A patent/CN104040310B/en not_active Expired - Fee Related
- 2012-10-26 RU RU2014121490A patent/RU2616569C2/en not_active IP Right Cessation
- 2012-10-26 SI SI201230601A patent/SI2776802T1/en unknown
- 2012-10-26 HU HUE12775721A patent/HUE028354T2/en unknown
- 2012-10-26 US US14/350,686 patent/US9140609B2/en not_active Expired - Fee Related
- 2012-10-26 KR KR1020147010899A patent/KR101947214B1/en active IP Right Grant
- 2012-10-26 DK DK12775721.9T patent/DK2776802T3/en active
- 2012-10-26 WO PCT/EP2012/071284 patent/WO2013060859A1/en active Application Filing
- 2012-10-26 ES ES12775721.9T patent/ES2572680T3/en active Active
- 2012-10-26 JP JP2014537636A patent/JP6077553B2/en not_active Expired - Fee Related
- 2012-10-26 PL PL12775721.9T patent/PL2776802T3/en unknown
- 2012-10-26 EP EP12775721.9A patent/EP2776802B1/en active Active
-
2016
- 2016-04-26 CY CY20161100349T patent/CY1117422T1/en unknown
- 2016-06-16 HR HRP20160690TT patent/HRP20160690T1/en unknown
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4318089A (en) | 1980-03-24 | 1982-03-02 | David Frankel | Infrared detector system |
USRE34789E (en) * | 1985-04-17 | 1994-11-15 | Thermoscan Inc. | Infrared electronic thermometer and method for measuring temperature |
US4849737A (en) | 1986-11-26 | 1989-07-18 | Matsushita Electric Works, Ltd. | Person-number detecting system |
US5555512A (en) * | 1993-08-19 | 1996-09-10 | Matsushita Electric Industrial Co., Ltd. | Picture processing apparatus for processing infrared pictures obtained with an infrared ray sensor and applied apparatus utilizing the picture processing apparatus |
WO1998047118A1 (en) * | 1997-04-14 | 1998-10-22 | Koninklijke Philips Electronics N.V. | Video motion detector with global insensitivity |
US20070110181A1 (en) * | 2005-11-16 | 2007-05-17 | Honeywell International, Inc. | Multi-frequency wireless transmitter |
Non-Patent Citations (1)
Title |
---|
T. BEDFORD: "Skin Temperature in Relation to the Warmth of the Environment", THE JOURNAL OF HYGIENE, vol. 35, no. 3, August 1935 (1935-08-01), pages 307 - 317 |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9140794B2 (en) | 2013-09-11 | 2015-09-22 | Google Technology Holdings LLC | Electronic device and method for detecting presence |
US9213102B2 (en) | 2013-09-11 | 2015-12-15 | Google Technology Holdings LLC | Electronic device with gesture detection system and methods for using the gesture detection system |
US9316736B2 (en) | 2013-09-11 | 2016-04-19 | Google Technology Holdings LLC | Electronic device and method for detecting presence and motion |
CN103815912A (en) * | 2014-01-26 | 2014-05-28 | 大连大学 | Real-time monitoring method for falling behaviors of old people living alone on basis of thermal infrared sensor array |
US11250683B2 (en) | 2016-04-22 | 2022-02-15 | Maricare Oy | Sensor and system for monitoring |
CN112005242A (en) * | 2018-05-18 | 2020-11-27 | 易希提卫生与保健公司 | Presence and absence detection |
WO2021130034A1 (en) * | 2019-12-26 | 2021-07-01 | Signify Holding B.V. | Systems and methods for fusing data from single pixel thermopiles and passive infrared sensors for counting occupants in open offices |
Also Published As
Publication number | Publication date |
---|---|
CN104040310B (en) | 2016-11-09 |
EP2776802B1 (en) | 2016-03-16 |
KR101947214B1 (en) | 2019-02-12 |
HRP20160690T1 (en) | 2016-07-15 |
RU2616569C2 (en) | 2017-04-17 |
CY1117422T1 (en) | 2017-04-26 |
US9140609B2 (en) | 2015-09-22 |
EP2776802A1 (en) | 2014-09-17 |
CN104040310A (en) | 2014-09-10 |
PL2776802T3 (en) | 2016-09-30 |
KR20140082726A (en) | 2014-07-02 |
JP6077553B2 (en) | 2017-02-08 |
ES2572680T3 (en) | 2016-06-01 |
HUE028354T2 (en) | 2016-12-28 |
JP2014534435A (en) | 2014-12-18 |
RU2014121490A (en) | 2015-12-10 |
SI2776802T1 (en) | 2016-07-29 |
DK2776802T3 (en) | 2016-06-27 |
US20140264035A1 (en) | 2014-09-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2776802B1 (en) | Infrared presence detector for detecting a presence of an object in a surveillance area | |
AU2007332785B2 (en) | Temperature detecting system and method | |
US10018510B2 (en) | Motion and presence detector | |
EP2974046B1 (en) | Portable device with temperature sensing | |
TWI776798B (en) | Motion and presence detector | |
JP6420877B2 (en) | Infrared presence detection by modeled background difference | |
US10739190B2 (en) | Motion sensor using linear array of infrared detectors | |
US11280500B2 (en) | Auto detection system based on thermal signals | |
EP3417432B1 (en) | Pyroelectric presence identification system | |
KR100404743B1 (en) | Apparatus for detecting minute movement using infrared sensor and spatial filter | |
US20140319320A1 (en) | Occupancy sensor device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 12775721 Country of ref document: EP Kind code of ref document: A1 |
|
DPE1 | Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 14350686 Country of ref document: US |
|
ENP | Entry into the national phase |
Ref document number: 20147010899 Country of ref document: KR Kind code of ref document: A |
|
ENP | Entry into the national phase |
Ref document number: 2014537636 Country of ref document: JP Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2012775721 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 2014121490 Country of ref document: RU Kind code of ref document: A |