JP2005214851A - Object detector, and electronic equipment provided with same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive object detector of high reliability about a stable operation for a long period, and of low limitation in view point of use, and provide an electronic equipment provided therewith. <P>SOLUTION: Five LEDs (infrared ray emitting elements) 3-0 to 3-4 are arranged to define a plane in a view from emission directions of the five LEDs 3-0 to 3-4. The five LEDs 3-0 to 3-4 emit a near infrared ray I1. A reflected ray I1' generated by an inspection object H gets incident thereby on one photoreception face of a PSD 4 through a convergence lens 6. The PSD 4 outputs a signal expressing a distance up to the inspection object H in response to a position of the incident ray within the photoreception face. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an object detection device that detects whether or not an object is in a certain range and detects a distance to the object and a direction in which the object is present.

  Conventionally, as an object detection device for detecting a human body / object (hereinafter referred to as “detection target”) in a non-contact manner, there is one disclosed in Japanese Patent Laid-Open No. 2002-350555 (Patent Document 1). This object detection apparatus includes a pyroelectric sensor and an infrared distance measuring sensor. The pyroelectric sensor has a feature that it can recognize the presence of a detection target because it detects heat rays (far infrared rays) without detecting a stationary object. The pyroelectric sensor has a wide viewing angle of about ± 50 ° and a long detection distance (˜5 m), but cannot detect the distance and direction to the detection target. On the other hand, the infrared distance measuring sensor emits near infrared rays from a light emitting element and detects reflected light from a detection target with a PSD (position detecting element). This infrared type distance measuring sensor has a narrow viewing angle of ± several degrees, but can know the distance to the detection target and is not easily affected by the color of the detection target. Therefore, by using the pyroelectric sensor and the infrared distance measuring sensor, it is possible to detect the presence of the detection target and to know the distance and direction to the detection target.

  FIG. 9A schematically shows a conventional object detection device 101 of this type as viewed from above, and FIG. 9B shows the interior of the object detection device 101 as viewed from the front. Is schematically shown.

  As shown in FIG. 9B, the object detection apparatus 101 includes a pyroelectric sensor 107 for detecting the presence of a detection target and a plurality of pieces for knowing the distance to the detection target in the main body casing 150. Infrared distance measuring sensors 102-0, 102-1, 102-2, 102-3, and 102-4 (hereinafter collectively referred to as reference numeral 102). The distance measuring sensors 102 are configured independently of each other and have equivalent performance. Each of the distance measuring sensors 102 includes an LED (infrared light emitting element) 103, a PSD (position detecting element) 104, and an IC (integrated circuit) 109 in a housing 108. The LEDs 103 of the distance measuring sensor 102 are located on the same straight line. That is, the LEDs 103 of the distance measuring sensor 102 are aligned.

  As shown in FIG. 9A, condensing lenses 105 and 106 corresponding to the LEDs 103 and the PSDs 104 are provided on the front surface of the main body casing 150. There are five condensing lenses 105 and 106, respectively. Near-infrared rays emitted from the LEDs 103 reach the detection target H through the corresponding condensing lens 105, are reflected, and enter the light receiving surface of the corresponding PSD 104 through the corresponding condensing lens 106. The PSD 104 outputs a signal representing the distance to the detection target H in accordance with the position of incident light within the light receiving surface.

  The pyroelectric sensor 107 is assembled in a can-type package and shielded so that minute far infrared rays can be detected. The PSD 104 of each distance measuring sensor 102 is assembled on a lead frame and shielded to improve distance measuring accuracy.

  As shown in the electrical block diagram of FIG. 10, the pyroelectric sensor 107 includes a sensor unit 107a and a signal processing circuit 107b for processing an output from the sensor unit 107a. Although only the distance measuring sensor 102-0 is specifically shown, each distance measuring sensor 102 includes an LED driving circuit 103B for driving the LED 103, a signal processing circuit 104B for processing the output of the PSD 104, A resistor 104C for sensitivity adjustment is included (the LED drive circuit 103B, the signal processing circuit 104B, and the resistor 104C constitute the IC 109 in FIG. 9). In the main body casing 150, a constant voltage circuit 130 for supplying a constant voltage to each distance measuring sensor 102 and a control circuit 140 for controlling the operation of each distance measuring sensor 102 are provided.

  FIG. 11 schematically shows the inside of the object detection apparatus 101 as viewed from the side.

  The LEDs 103 are arranged by changing the emission direction of infrared rays (near infrared rays) so as to cover the detection range E (shown by hatching) of the pyroelectric sensor 107. Here, arrows a-0, a-1, a-2, a-3, and a-4 in the figure represent the infrared emission direction of the LED 103.

  According to the object detection apparatus 101 having the above configuration, the pyroelectric sensor 107 is always in an operating state. When the detection target H exists within a certain distance (detection range) from the pyroelectric sensor 107, the pyroelectric sensor 107 detects a far infrared ray emitted from the detection target H and outputs a detection signal. Based on the detection signal, each distance measuring sensor 102 starts a distance measuring operation under the control of the control circuit 140. Usually, the ranging operation is repeated intermittently in the order of the ranging sensors 102-0, 102-1, 102-2, 102-3, and 102-4. When a certain distance measuring sensor 102 detects the distance to the target during the distance measuring operation, the position of the detection target H with respect to the object detecting device 101 based on the distance measuring direction and distance information of the distance measuring sensor 102 Can be identified.

  By the way, the conventional object detection apparatus 101 mechanically drives the LED 103 to change the direction in which the LED 103 emits near infrared rays, and scans the detection range with the near infrared rays of the LED 103. In such mechanical scanning, mechanical noise is generated when the LED 103 is driven, the response of the LED 103 is limited, or the driving portion of the LED 103 is worn. Therefore, the object detection apparatus 101 has a problem that it needs maintenance and has low reliability for long-term stable operation.

Further, in the method using a plurality of distance measuring sensors 102 each having a casing 108 and configured independently from each other, the size of the apparatus (main body 150) is increased as a whole. For this reason, for example, there is a limitation in use such that it cannot be mounted on a small device. In addition, since the number of parts is large, there is a problem that the cost is high.
JP 2002-350555 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an object detection apparatus that is highly reliable with respect to long-term stable operation, has a small limitation in terms of application, and is inexpensive, and an electronic apparatus including the same.

In order to solve the above-mentioned problem, an object detection device according to a first invention is
A plurality of light emitting elements that emit detection light toward a detection target;
A position detection element that has one light receiving surface on which the detection light reflected by the detection target is incident, and that outputs a signal representing a distance to the detection target in accordance with the position of the incident light within the light receiving surface; With
The plurality of light emitting elements are arranged so as to define a plane when viewed from the emission direction of the plurality of light emitting elements.

  According to the object detection apparatus having the above configuration, for example, detection light (typically infrared rays) is sequentially emitted from the plurality of light emitting elements at different times. This detection light is reflected by the detection target and enters the light receiving surface of the position detection element. Therefore, the direction in which the detection target exists is known according to the emission direction of the detection light. The position detection element outputs a signal representing the distance from the object detection device to the detection target in accordance with the position of incident light within its light receiving surface (triangulation method). In this way, the direction and distance from the object detection device to the detection target can be known.

  Further, since the plurality of light emitting elements are arranged so as to define the plane when viewed from the emission direction of the plurality of light emitting elements, the plurality of detection lights emitted from the plurality of light emitting elements do not exist on the same plane. As a result, a two-dimensional region can be scanned with the plurality of light emitting elements without mechanically driving the plurality of light emitting elements.

  In addition, since mechanical driving of the plurality of light emitting elements is not required, noise is not generated and the noise is excellent. Moreover, there is no limitation of the responsiveness by the mechanical drive. Further, since the mechanical drive does not cause wear, there is no need for maintenance. Therefore, long-term stable operation is possible. In other words, the reliability of long-term stable operation is high.

  In addition, since the position detection element has one light receiving surface on which detection light reflected by the detection target is incident, a diagram including a plurality of position detection elements (that is, a plurality of light receiving surfaces). Compared to the conventional example of 9, the size of the apparatus can be reduced. Therefore, the limitation in use can be reduced, and the number of parts is small, so that the cost is reduced.

  In the object detection device of one embodiment, the plurality of light emitting elements are included in one chip.

  According to the object detection device of the above embodiment, since the plurality of light emitting elements are included in one chip, the size of the device can be further reduced.

  The object detection apparatus according to an embodiment includes a pyroelectric sensor that senses heat generated by the detection target.

  According to the object detection device of the above embodiment, since the pyroelectric sensor senses the heat generated by the detection target, for example, the presence of a human body or the like can be detected.

  In the object detection device according to an embodiment, the detection light passes through a pyroelectric sensor sensing region where the pyroelectric sensor can sense the presence of the detection target.

  According to the object detection device of the above embodiment, since the detection light passes through the pyroelectric sensor sensing area where the presence of the detection target can be sensed by the pyroelectric sensor, the direction of the detection target detected by the pyroelectric sensor is determined. And distance information can be obtained. That is, it is possible to measure the distance from the object detection device to the detection target, and to grasp in which direction the detection target exists as viewed from the object detection device.

  In the object detection apparatus according to an embodiment, the detection light forms a plurality of beam spots arranged in a lattice pattern.

  According to the object detection device of the above embodiment, since the plurality of beam spots by the detection light are arranged in a lattice shape, the area that can be scanned by the plurality of light emitting elements can be further expanded.

  In the object detection device according to one embodiment, the plurality of light emitting elements are arranged in a grid pattern.

  According to the object detection apparatus of the above embodiment, since the plurality of light emitting elements are arranged in a lattice shape, the area that can be scanned with the plurality of light emitting elements can be further expanded.

  The object detection apparatus according to an embodiment includes a signal processing circuit that is formed integrally with the position detection element and that receives a signal from the position detection element.

  According to the object detection device of the above embodiment, since the position detection element and the signal processing circuit are integrally formed, the size of the device can be further reduced.

  According to a second aspect of the present invention, there is provided an electronic apparatus including the first object detection apparatus.

  In this specification, an electronic device broadly refers to a device that performs electrical processing using the output of an object detection device.

  According to the electronic apparatus having the above configuration, since the first object detection device is provided, an appropriate operation corresponding to the position of the detection target is performed based on the signal by receiving a signal output from the object detection device. Yes.

  Since the object detection device of the first invention emits detection light from a plurality of light emitting elements toward the detection target and receives the detection light reflected by the detection target on the light receiving surface of the position detection element, the object detection device The distance to the detection target can be detected.

  Further, by arranging a plurality of light emitting elements so as to define a plane as viewed from the emission direction of the plurality of light emitting elements, a plurality of detection lights emitted from the plurality of light emitting elements do not exist on the same plane, A two-dimensional region can be scanned with a plurality of light emitting elements without mechanically driving the plurality of light emitting elements.

  In addition, since mechanical driving of the plurality of light emitting elements is not required, noise is not generated and the noise is excellent. Moreover, there is no limitation of the responsiveness by the mechanical drive. Further, since the mechanical drive does not cause wear, there is no need for maintenance. Therefore, long-term stable operation is possible. In other words, the reliability of long-term stable operation is high.

  In addition, since the position detection element has one light receiving surface on which detection light reflected by the detection target is incident, a diagram including a plurality of position detection elements (that is, a plurality of light receiving surfaces). Compared to the conventional example of 9, the size of the apparatus can be reduced. Therefore, the limitation in use can be reduced, and the number of parts is small, so that the cost is reduced.

  Since the electronic apparatus according to the second aspect of the present invention includes the first object detection device, an appropriate operation can be performed based on a signal output from the object detection device.

  Hereinafter, the object detection apparatus of the present invention will be described in detail with reference to the illustrated embodiments.

  FIG. 1A schematically shows an object detection device 1 according to an embodiment of the present invention as viewed from above, and FIG. 1B shows the interior of the object detection device 1 from the front. The appearance is shown schematically.

  As shown in FIG. 1B, the object detection device 1 includes a pyroelectric sensor 7 that senses heat generated by a detection target (such as a human body or an object) in a main body casing 50, and a self-detection target. And an infrared distance measuring sensor 2 for knowing the distance.

  The distance measuring sensor 2 includes five LEDs (infrared light emitting elements) 3-0, 3-1, 3-2, 3-3, which are examples of a plurality of light emitting elements, in an integrated housing 20. 3-4, one PSD (position detecting element) 4, and an IC (integrated circuit) 9. The LEDs 3-0, 3-1, 3-2, 3-3, 3-4 are included in one chip. The LEDs 3-0 to 3-4 are positioned on the same V-shaped line. That is, the LEDs 3-0 to 3-4 are arranged in a V shape without being aligned. More specifically, the LEDs 3-0 to 3-4 are arranged in a V shape on the same plane. Thereby, the near infrared rays emitted from the LEDs 3-0 to 3-4 are not present on the same plane.

  Although not shown, the pyroelectric sensor 7 includes a sensor unit and a signal processing circuit that processes the output of the sensor unit, like the conventional object detection device 101. The distance measuring sensor 2 includes an LED driving circuit for individually driving the LEDs 3-0 to 3-4, a signal processing circuit for processing the output of the PSD 4, and a resistance for adjusting sensitivity. Is included. Although this LED drive circuit and resistor are not shown, the signal processing circuit constitutes the IC 9. In the main body casing 50, a constant voltage circuit that supplies a constant voltage to the distance measuring sensor 2 and a control circuit that controls the operation of the distance measuring sensor 2 are provided.

  As shown in FIG. 1A, a condensing lens 5 is provided on the front surface of the main body casing 50 in correspondence with the LEDs 3-0 to 3-4, and in correspondence with PSD4. A condensing lens 6 is provided. Each of the LEDs 3-0 to 3-4 emits a near infrared ray I1 as an example of detection light. This near infrared ray I1 reaches the detection target H through the corresponding condensing lens 5, and the reflected light I1 'from the detection target H passes through the condensing lens 6 and enters one light receiving surface of the PSD 4. In the present embodiment, the condensing lens 9 is a toroidal lens in order to properly collect the reflected light from multiple directions onto the PSD 4. The PSD 4 has one light receiving surface and is included in one chip. The PSD 4 outputs a signal representing the distance to the detection target H according to the position of the incident light within the one light receiving surface. The PSD 4 is formed integrally with a signal processing circuit that processes the output of the PSD 4. The pyroelectric sensor 7 detects a heat ray (far infrared ray) I0 emitted from the detection target H.

  FIG. 2 schematically shows a light-emitting side beam state of the object detection apparatus 1.

  As shown in FIG. 2, a lens 8 is disposed in front of the condensing lens 5 in FIG. 1 (a) (in FIG. 2, illustration of the peripheral effect lens is omitted). Near-infrared rays i0,..., I4 emitted from the LEDs 3-0,. That is, the near infrared rays i0 to i4 pass through the condenser lens 5 and reach the lens 8. Then, the near infrared rays i0 to i4 that have passed through the lens 8 become parallel light and travel toward the detection target H. At this time, the viewing angle of the sensor is determined by the emission angles of the near infrared rays i0 to i4 with respect to the lens 8. This viewing angle is determined by the distance between the LEDs 3-0 to 3-4 and the distance from the LEDs 3-0 to 3-4 to the lens 8 (lens focal length).

  According to the object detection device 1 configured as described above, the LEDs 3-0,..., 3-4 are not arranged on the same straight line, so the beam spots by the LEDs 3-0,. The beam spot exists two-dimensionally. As a result, even if the LEDs 3-0,..., 3-4 are not mechanically driven, the distance measurement possible area by the LEDs 3-0,. That is, two-dimensional scanning can be performed with the LEDs 3-0 to 3-4 without mechanically driving the LEDs 3-0 to 3-4. Therefore, the distance from the object detection device 1 to the detection target H can be detected efficiently.

  Hereinafter, the case where the object detection device 1 is attached to an indoor unit 60 of an air conditioner as an example of an electronic device will be described with reference to FIGS. 3A is a schematic view of the room in which the indoor unit 60 is installed as viewed from above, FIG. 3B is a schematic view of the room as viewed from the side, and FIG. It is the schematic diagram which looked at the said room from the front.

  The near infrared rays i0 to i4 from the object detection device 1 are not on the same plane, and the near infrared rays i0, i1 and i2 hit all of the detection targets H1, H2 and H3. Thereby, the object detection apparatus 1 can detect all the detection targets H1, H2, and H3 in the room without mechanically driving the LEDs 3-0 to 3-4. Therefore, the indoor unit 60 can select an appropriate operation based on the detection result of the object detection device 1 without mechanically driving the LEDs 3-0 to 3-4. For example, the indoor unit 60 can appropriately select the temperature, wind direction, intensity, and the like of the air supplied to the room according to the position information of the person in the room. That is, the object detection device 1 can improve the operation efficiency of the indoor unit 60.

  FIG. 4A shows a schematic view of a room in which a conventional air conditioner indoor unit 160 is installed as seen from above, and FIG. 4B shows a schematic view of the room seen from the side, and FIG. ) Shows a schematic view of the room as seen from the front. A conventional object detection device 101 is assembled to the indoor unit 160.

  The near-infrared rays i100,..., I104 from the conventional object detection apparatus 101 are on the same plane, and the near-infrared ray i102 strikes only the detection target H3 among the detection targets H1, H2, and H3. Thus, the conventional object detection device 101 can detect only the detection target H3 among the detection targets H1, H2, and H3 in the room when the LED 103 is not mechanically driven (in the figure, the detectable detection target H3). Is shaded, while the detection target H that cannot be detected is not shaded.). Therefore, unless the LED 103 is mechanically driven, the indoor unit 160 cannot perform an appropriate operation.

  FIG. 5 is a schematic view of a self-propelled cleaner 70 as an example of an electronic device as viewed obliquely from above. The object detection device 1 is assembled to the self-propelled cleaner 70.

  The beams B1, B2, and B3 from the object detection apparatus 1 are not on the same plane, and the beams B2 and B3 hit a step. Thereby, the said object detection apparatus 1 can detect the level | step difference in front of the self-propelled cleaner 70, without driving LED3-0, ..., 3-4 mechanically. Therefore, the self-propelled cleaner 70 can avoid a step on the basis of the detection result of the object detection device 1 without mechanically driving the LEDs 3-0 to 3-4. Therefore, the self-propelled cleaner 70 can travel efficiently while avoiding obstacles.

  FIG. 6A shows a schematic view of an infrared distance measuring sensor 202 provided in an object detection apparatus according to another embodiment of the present invention as viewed from the front, and FIG. 6B shows the distance measuring sensor 202 side. FIG. 6C shows a schematic view of the distance measuring sensor 202 as viewed from above, and FIG. 6D illustrates the formation state of the beam spot BS by the distance measuring sensor 202. FIG. The schematic diagram for doing is shown.

  As shown in FIG. 6A, the distance sensor 202 includes 25 LEDs (infrared light emitting elements) 203 as an example of a plurality of light emitting elements and one PSD (position detecting element). 204). The LEDs (infrared light emitting elements) 203 are arranged in a grid pattern. As a result, the near-infrared rays I2 emitted from the LED 203 spread in the vertical direction as shown in FIG. 6B, and spread in the horizontal direction as shown in FIG. 6C. As a result, the near-infrared rays I2 form beam spots BS arranged in a lattice pattern on the surface of the detection target, as shown in FIG. 6 (d).

  According to the distance sensor 202, the reflected light from the object A is incident on the point a on the light receiving surface of the PSD 204 and reflected from the object B, as shown in FIGS. Enters the point b on the light receiving surface of the PSD 204.

  8A to 8D, the reflected light from the object A is incident on the point a on the light receiving surface of the PSD 204, and the reflected light from the object B is incident on the point b on the light receiving surface of the PSD 204. The reflected light from the object C enters the point c on the light receiving surface of the PSD 204, and the reflected light from the object D enters the point d on the light receiving surface of the PSD 204.

  Thus, the incident position of the reflected light with respect to the light receiving surface of the PSD 204 varies depending on the positions of the objects A, B, C, and D. Therefore, since the signal output from the PSD also varies depending on the positions of the objects A, B, C, and D, the position of the object A can be obtained based on the signals. That is, a two-dimensional distance measurement area can be obtained without mechanically driving the LED 203.

  As described above, the object detection apparatus is a small object detection apparatus in which a multi-beam infrared sensor is combined with a pyroelectric sensor.

  In the above embodiment, the object detection device is mounted on an air conditioner or a self-propelled cleaner, but the object detection device may be mounted on various home appliances or robots.

  In the above embodiment, five LEDs are arranged in a V shape when viewed from the emission direction of the five LEDs. However, for example, five LEDs are arranged in a W shape when viewed from the emission direction of the five LEDs. You may arrange | position LED. That is, for example, when the object detection apparatus includes n (n: a natural number of 3 or more) LEDs, the n LEDs may be arranged so as to define a plane when viewed from the emission direction of the n LEDs. .

  For example, when the object detection device includes n (n: a natural number of 3 or more) LEDs, two near infrared rays are present on the same plane among n near infrared rays emitted by the LEDs. The other near infrared rays may be present on a plane other than the plane.

1A and 1B are schematic views of an object detection apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing a light emission side beam state of the object detection apparatus of FIG. FIGS. 3A to 3C are schematic views of a room with an indoor unit of an air conditioner on which the object detection device of FIG. 1 is mounted. 4A to 4C are schematic views of a room having an indoor unit of an air conditioner equipped with a conventional object detection device. FIG. 5 is a schematic view of a self-propelled cleaner equipped with the object detection device of FIG. 1 as viewed obliquely from above. FIGS. 6A to 6C are schematic views of an infrared range sensor provided in an object detection apparatus according to another embodiment of the present invention. FIG. 6D is a diagram of a beam spot by the range sensor. It is a schematic diagram. FIG. 7 is a schematic diagram for explaining distance measurement by the distance measuring sensor of FIG. FIG. 8 is a schematic diagram for explaining distance measurement by the distance measuring sensor of FIG. 9A and 9B are schematic views of a conventional object detection apparatus. FIG. 10 is an electrical block diagram of the conventional object detection apparatus. FIG. 11 is a schematic view of the inside of the conventional object detection apparatus as viewed from the side.

Explanation of symbols

3-0, 3-1, 3-2, 3-3, 3-4, 203 LED
4,204 PSD
7 Pyroelectric sensor 9 IC
60 Air conditioner indoor unit 70 Self-propelled vacuum cleaner BS Beam spot H, H1, H2, H3 Detection target I1, i0, i1, i2, i3, i4 Near infrared

Claims (8)

A plurality of light emitting elements that emit detection light toward a detection target;
A position detection element that has one light receiving surface on which the detection light reflected by the detection target is incident, and that outputs a signal representing a distance to the detection target in accordance with the position of the incident light within the light receiving surface; With
The object detecting device, wherein the plurality of light emitting elements are arranged so as to define a plane when viewed from an emission direction of the plurality of light emitting elements. The object detection apparatus according to claim 1,
The object detection apparatus, wherein the plurality of light emitting elements are included in one chip. The object detection apparatus according to claim 1,
An object detection apparatus comprising a pyroelectric sensor that senses heat generated by the detection target. The object detection device according to claim 3,
The object detection apparatus according to claim 1, wherein the detection light passes through a pyroelectric sensor sensing region where the presence of the detection target can be sensed by the pyroelectric sensor. The object detection apparatus according to claim 1,
The object detection apparatus, wherein the detection light forms a plurality of beam spots arranged in a lattice shape. The object detection device according to claim 2,
The object detection apparatus, wherein the plurality of light emitting elements are arranged in a grid pattern. The object detection apparatus according to claim 1,
An object detection apparatus comprising a signal processing circuit formed integrally with the position detection element and receiving a signal from the position detection element.   An electronic apparatus comprising the object detection device according to claim 1.

Images