JP2009216677A - Reflecting sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of elements while enabling to detect by each infrared ray spot light unit, in a reflecting sensor using an infrared ray. <P>SOLUTION: In the reflecting sensor, it is assumed that the number of infrared ray emitting elements 21 are m1 in a light emitting part 20 side, the dividing ratio of a first lens system 22 of the light emitting system side are n1, the number of infrared ray receiving elements 31 in a light receiving part 30 side are m2, and the dividing ratio of a second lens system 32 of the light receiving side are n2 (m1≠m2, n1≠n2), the relation between the number of the infrared ray emission elements 21 being m1 and the dividing ratio n1 of the first lens system 22 of the light emission side and the number of the infrared ray receiving element 31 being m2 andthe dividing ratio n2 of the second lens system 32 are made m1×n1=m2×n2. Where, if both the infrared ray emission elements 21 and the infrared ray receiving elements 31 are ≥2, and in the first lens system 22 and the second lens system 32, the compound eyes of ≥2 in the dividing ratio are used, each of infrared ray emission element 21 is alternatively scan driven in a prescribed order and the light receiving signal out putted from each infrared receiving element 32 is monitored individually. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a reflection type sensor using infrared rays, for example, attached to an invisible part or a ceiling part of an automatic door and using a floor near the entrance and exit as a monitoring area, and more specifically, an object existing in the monitoring area. The present invention relates to a technique for accurately detecting (person) including its position information.

  Automatic door sensors include the ultrasonic type, the pressure mat type that detects weight, and the optical type (reflective type). Each has advantages and disadvantages, but the monitoring area can be set clearly, and the product price is relatively low. In general, many reflective sensors using infrared rays are employed because of their low cost.

  FIG. 7 shows a first conventional example of a reflection type sensor for use as an automatic door, for example. The automatic door reflection sensor 1C includes a light emitting unit 20 having an infrared light emitting element 21 as a transmitting side and a light receiving unit 30 having an infrared light receiving element 31 as a receiving side, and transmits and receives via infrared rays. Is done.

  The light emitting unit 20 and the light receiving unit 30 are juxtaposed on a circuit board 11 in the casing 10 that is arranged in the vicinity of an unillustrated automatic door or near the ceiling (not shown). A first lens system 22 and a second lens system 32 corresponding to each of the light receiving unit 30 side are provided.

  In the first conventional example, monocular lenses 22a and 32a are used for the first lens system 22 on the light emitting side and the second lens system 32 on the light receiving side, respectively, and the infrared light emitting element 21 and the infrared light receiving element 31 are used. Both are four elements (infrared light emitting elements 21a to 21d, infrared receiving elements 31a to 31d). In addition, when it is not necessary to distinguish each infrared light emitting element 21a-21d, the reference code | symbol is set to 21, Similarly, when it is not necessary to distinguish each infrared light receiving element 31a-31d, the reference code | symbol is used. 31.

  The infrared light emitting elements 21a to 21d and the infrared light receiving elements 31a to 31d are mounted on the circuit board 11 in a horizontal row (horizontal direction in FIG. 7) at equal intervals, and the floor surface near the entrance / exit of the automatic door is used as the monitoring area A. The infrared spotlights SPa to SPd are irradiated in a line from the infrared light emitting elements 21a to 21d onto the monitoring area A through the first lens system 22. Reference numerals 23a to 23d are assigned to the optical axes of the infrared light emitting elements 21a to 21d shown by solid lines.

  On the other hand, the infrared light receiving elements 31a to 31d are arranged so that the optical axes 33a to 33d shown in chain lines coincide with the optical axes 23a to 23d of the infrared light emitting elements 21a to 21d on the monitoring area A. And / or the inclination of the second lens system 32 is adjusted.

  Thereby, each infrared spot light SPa-SPd by the infrared light emitting elements 21a-21d overlaps the spot-shaped light receiving areas RPa-RPd of the infrared light receiving elements 31a-31d, and the infrared light emitted from the infrared light emitting element 21a is received by infrared light. The light is received by the element 31a, and similarly, infrared rays are exchanged between 21b and 31b, 21c and 31c, and 21d and 31d.

  In the example shown in FIG. 7, for convenience of explanation, a set of only one row of the infrared light emitting elements 21 a to 21 d and the infrared light receiving elements 31 a to 31 d is shown, but in the actual monitoring area A, as shown in FIG. Multi-row monitoring areas A1 to A4 are set on the floor near the doorway of the automatic door (see, for example, Patent Document 1).

  In the monitoring area A, each infrared light receiving element 31a˜ is present depending on whether or not an object (a person, a small animal, etc. includes a loading platform, etc., but “person” is assumed in the following description) is present. Since the amount of light received at 31d changes, the control unit controls the opening and closing of the door by driving a door engine (both not shown) based on the change in the amount of received light.

  By the way, not only the presence / absence determination of a person in the monitoring area A, but recently, pixel-like information in the infrared spot light unit is obtained from the monitoring area A, for example, the position of the person in the monitoring area A is determined. Detecting, judging the approaching / leaving of a person with respect to an automatic door, and preventing malfunction due to various noises are performed.

  In order to obtain such pixel-like information, the control unit alternately scans and drives the infrared light emitting elements 21a to 21d according to a predetermined order, and receives all the light reception signals output from the infrared light receiving elements 31a to 31d. The light reception level of the light receiving unit 30 is monitored.

  Thereby, for example, when the light receiving level of the light receiving unit 30 exceeds a predetermined threshold when the infrared light emitting element 21b is turned on, it can be determined that there is a person at the position of the infrared spot light SPb.

  However, in the first conventional example, when the monitoring area A is to be expanded in the horizontal direction in FIG. 7, the number of elements must be increased on both the light emitting unit 20 side and the light receiving unit 30 side accordingly. There is a problem that the cost increases.

  As a method for reducing the number of elements, a method using a split lens (compound eye lens) in a lens system is known. FIG. 9 shows a reflective sensor 1D for use in an automatic door, for example, according to a second conventional example in which a split lens is used in the lens system. In the description of the second conventional example, the same reference numerals are used for components that are substantially the same as those in the first conventional example.

  In this automatic door reflection type sensor 1D, as an example, both the light emitting unit 20 and the light receiving unit 30 have two elements (infrared light emitting elements 21a and 21b; infrared light receiving elements 31a and 31b). For the lens system 22 and the second lens system 32 on the light receiving side, two-divided lenses 22b and 32b having a division ratio of “2” are used.

  According to this, in FIG. 9, each left lens portion of the two-divided lenses 22b and 32b is L, and each right lens portion is R, and the infrared rays emitted from one infrared light emitting element 21a in the light emitting unit 20 are divided into two divided lenses. The infrared light of the optical axis 23aL and the infrared light of the optical axis 23aR are divided by 22b, and two infrared spot lights SPaL and SPaR are irradiated to the monitoring area A from the infrared light emitting element 21a.

  Similarly, the infrared light emitted from the other infrared light emitting element 21b in the light emitting unit 20 is divided into infrared light having an optical axis 23bL and infrared light having an optical axis 23bR by the two-divided lens 22b, and the infrared light emitting element 21b. To the monitoring area A is irradiated with two infrared spot lights SPbL and SPbR.

  On the other hand, the optical axis (light receiving axis) of one infrared light receiving element 31a on the light receiving unit 30 side is divided into two optical axes 33aL and 33aR by the two-divided lens 32b, and these optical axes 33aL and 33aR are monitored. On the area A, adjustment is made so as to coincide with the optical axes 23aL and 23aR of the infrared light emitting element 21a. The position adjustment (position alignment) of each optical axis can be performed, for example, by tilting or moving the lens system.

  Accordingly, the infrared light receiving element 31a has two light receiving areas RPaL and RPaR, and these light receiving areas RPaL and RPaR are superimposed on the infrared spot light SPaL and SPaR by the infrared light emitting element 21a on the monitoring area A.

  Similarly, the optical axis of the other infrared light receiving element 31b on the light receiving unit 30 side is divided into two optical axes 33bL and 33bR by the two-divided lens 32b, and these optical axes 33bL and 33bR are infrared rays on the monitoring area A. Adjustment is made so as to coincide with the optical axes 23bL and 23bR of the light emitting element 21b.

  Thereby, the infrared light receiving element 31b has two light receiving areas RPbL and RPbR, and these light receiving areas RPbL and RPbR are superimposed on the infrared spot light SPbL and SPbR by the infrared light emitting element 21b on the monitoring area A.

  Thus, according to the reflective sensor 1D for automatic doors according to the second conventional example, the infrared light emitted from one infrared light emitting element 21a is divided into two infrared lights and irradiated to the monitoring area A, respectively. Reflected light is received by one of the infrared light receiving elements 31a.

  In addition, the infrared light emitted from the other infrared light emitting element 21b is divided into two infrared lights and irradiated to the monitoring area A, and each reflected light is received by the other infrared light receiving element 31b. As compared with the first conventional example, the monitoring area A having the same area as the first conventional example can be monitored with the same number of infrared spot lights as the first conventional example, that is, with the same reliability. .

  However, in the second conventional example, there is a problem that detection in units of each infrared spot light cannot be performed as in the first conventional example.

  That is, even if the infrared light emitting elements 21a and 21b are alternately turned on, two infrared spot lights SPaL and SPaR are simultaneously irradiated from the infrared light emitting element 21a, and two infrared rays are emitted from the infrared light emitting element 21b. Spot lights SPbL and SPbR are irradiated simultaneously.

  Therefore, for example, when the infrared light emitting element 21a is turned on, even if the light receiving level of the infrared light receiving element 31a paired with the infrared light emitting element 21a exceeds the threshold value for opening the door, whether or not a person has been detected by either the infrared spot light SPaL or SPaR I cannot judge until.

JP 2007-271537 A

  Accordingly, an object of the present invention is to enable the detection of each infrared spot light unit and reduce the number of elements in a reflective sensor using infrared rays.

  In order to solve the above problems, the present invention provides a light emitting unit including an infrared light emitting element, a light receiving unit including an infrared light receiving element, a drive signal to the infrared light emitting element, and a light receiving signal output from the infrared light receiving element. And a control unit that generates a control signal based on a predetermined floor surface as a monitoring area, and a plurality of infrared spot lights are transmitted to the monitoring area through the first lens system on the light emission side from the light emitting unit. In a reflective sensor that irradiates in an array and receives reflected light from the monitoring area of each infrared spot light by the light receiving unit through the second lens system on the light receiving side, the infrared light emitting element on the light emitting unit side The number is m1, the division ratio of the first lens system on the light emitting side is n1 (m1, n1 is a positive integer of 1 or more), and the number of the infrared light receiving elements on the light receiving side is m2. The division ratio of the second lens system on the light receiving side is n2 (m2, n2 are positive integers of 1 or more, provided that m1 ≠ m2, n1 ≠ n2), and the number m1 of the infrared light emitting elements and the first light emitting side first. The relationship between the division ratio n1 of the lens system and the number m2 of the infrared light receiving elements and the division ratio n2 of the second lens system on the light receiving side is expressed as m1 × n1 = m2 × n2 (where n1 / N1> n2) (where n2 / n1 <n2 where n2 / n1 <n2 is divisible, and n1 and n2 have a common divisor other than 1 even when each of the divided values is not divisible)) Yes.

  In the present invention, when a monocular lens having a division ratio of 1 is used for the first lens system on the light emitting side, the control unit alternately scans and drives the m1 infrared light emitting elements in a predetermined order, and the m2 The light reception signal output from each infrared light receiving element is monitored.

  In the present invention, when a monocular lens having a division ratio of 1 is used for the second lens system on the light receiving side, the control unit simultaneously drives the m1 infrared light emitting elements and outputs from the m2 infrared light receiving elements. Each received light signal is monitored.

  In the present invention, the number m1 of the infrared light emitting elements and the number m2 of the infrared light receiving elements are both 2 or more, and the split ratio is 2 for each of the first lens system on the light emitting side and the second lens system on the light receiving side. When the above compound eye lens is used, the control unit alternately scans and drives the m1 infrared light emitting elements in a predetermined order, and individually receives the light reception signals output from the m2 infrared light receiving elements. Monitor.

  According to the present invention, the number of infrared light emitting elements on the light emitting unit side is m1, the division ratio of the first lens system on the light emitting side is n1 (m1 and n1 are positive integers of 1 or more), and infrared light reception on the light receiving unit side. Assuming that the number of elements is m2 and the division ratio of the second lens system on the light receiving side is n2 (m2, n2 are positive integers of 1 or more, where m1 ≠ m2, n1 ≠ n2), the number of infrared light emitting elements m1 and light emission The relationship between the division ratio n1 of the first lens system on the side, the number m2 of infrared light receiving elements, and the division ratio n2 of the second lens system on the light reception side is expressed as m1 × n1 = m2 × n2 (where n1> n2 n1 / n2, n1 <n2 when each division value of n2 / n1 is divisible, and even when each division value is not divisible, there is a case where a common divisor other than 1 exists in n1, n2). Compared to the first conventional example, the light emitting part side Alternatively, the number of elements on the light receiving unit side can be reduced to half or less.

  When a monocular lens having a division ratio of 1 is used for the first lens system on the light emission side, m1 infrared light emitting elements are alternately scanned and driven in a predetermined order, and light received from the m2 infrared light receiving elements is received. By monitoring the signal, detection can be performed in units of each infrared spotlight as in the first conventional example.

  When a monocular lens having a division ratio of 1 is used for the second lens system on the light receiving side, m1 infrared light emitting elements are simultaneously driven and each light receiving signal output from the m2 infrared light receiving elements is monitored. As a result, as in the first conventional example, detection in units of each infrared spot light is possible.

  The number m1 of the infrared light emitting elements and the number m2 of the infrared light receiving elements are both 2 or more, and compound eye lenses having a division ratio of 2 or more are used for the first lens system on the light emitting side and the second lens system on the light receiving side, respectively. In this case, the m1 infrared light emitting elements are alternately scanned and driven in a predetermined order, and the light receiving signals output from the m2 infrared light receiving elements are individually monitored, whereby the first conventional technique described above. As in the example, detection can be performed in units of each infrared spot light.

  Next, several embodiments of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing a configuration of a reflective sensor according to the first embodiment of the present invention, FIG. 2 is a schematic diagram showing a control unit in the first embodiment, and FIG. 3 is a reflection according to the second embodiment of the present invention. FIG. 4 is a schematic diagram showing a control unit in the second embodiment. FIG. 5 is a schematic diagram showing the configuration of the light emitting unit side and the light receiving unit side of the reflective sensor according to the third embodiment of the present invention. FIG. 6 is a schematic diagram showing the configuration of the light emitting unit side and the light receiving unit side of the reflective sensor according to the fourth embodiment of the present invention.

  The reflective sensor according to the present invention can be used not only for automatic door opening / closing control, but also for detecting an entry / exit person (object) with respect to a specific building, room or place and counting the number of persons. However, in each of the embodiments described below, the application is used for automatic door opening / closing control. Further, in the description of this embodiment, the same reference numerals are used for constituent elements that are substantially the same as those of the conventional example described above with reference to FIGS.

  First, a reflective sensor 1A according to a first embodiment of the present invention will be described with reference to FIGS. This first embodiment corresponds to claims 1 and 2.

  In the automatic door reflection type sensor 1A, the number of infrared light receiving elements 31 is m2, the division ratio of the second lens system 32 on the light receiving side is n2, and the monocular lens 22a having a division ratio of 1 is set on the first lens system 22 on the light emitting side. , The number of infrared light emitting elements 21 is set to m2 × n2, and the control unit 12 alternately scans and drives m2 × n2 infrared light emitting elements 21 in a predetermined order, and receives m2 infrared light receiving elements. The light reception signal output from the element 31 is constantly monitored.

  In the example of FIG. 1, the infrared light emitting elements 21 of the light emitting unit 20 are four elements (infrared light emitting elements 21a to 21d), while the infrared light receiving elements 31 of the light receiving unit 30 are two elements (infrared light receiving elements 31a and 31b). ), A monocular lens 22a is used for the first lens system 22 on the light emitting side, and a two-divided lens (compound lens) 32b with a division ratio of “2” is used for the second lens system 32 on the light receiving side.

  The control unit 12 may be a CPU (Central Processing Unit) or a microcomputer. The control unit 12 outputs a drive signal to the infrared light emitting element 21 and compares the light reception signal output from the infrared light receiving element 31 with a predetermined threshold value to generate an automatic door opening / closing signal.

  Although not shown, the light reception signal output from the infrared light receiving element 31 is input to the control unit 12 via the A / D converter, and the drive signal for the infrared light emitting element 21 is sent to the light emitting driver circuit. Given.

  The infrared light emitting elements 21a to 21d and the infrared light receiving elements 31a and 31d are both mounted on the circuit board 11 in a horizontal row (in the left-right direction in FIG. 1) at a predetermined interval, and the first lens from the infrared light emitting elements 21a to 21d. Infrared spot lights SPa to SPd are irradiated in a line on the monitoring area A through the monocular lens 22a of the system 22. Reference numerals 23a to 23d are optical axes of the infrared light emitting elements 21a to 21d.

  On the other hand, the optical axis (light receiving axis) of one infrared light receiving element 31a on the light receiving unit 30 side is divided into two optical axes 33aL and 33aR by the two-divided lens 32b, and these optical axes 33aL and 33aR are monitored. On the area A, the infrared light emitting elements 21a and 21c are adjusted to coincide with the optical axes 23a and 23c. The position adjustment (position alignment) of each optical axis can be performed, for example, by tilting or moving the lens system.

  Thereby, the infrared light receiving element 31a has two light receiving areas RPaL and RPaR, and these light receiving areas RPaL and RPaR are infrared spot light SPc by the infrared light emitting element 21c and infrared light by the infrared light emitting element 21a on the monitoring area A, respectively. It is superimposed on the spot light SPa.

  Similarly, the optical axis of the other infrared light receiving element 31b on the light receiving unit 30 side is divided into two optical axes 33bL and 33bR by the two-divided lens 32b, and these optical axes 33bL and 33bR are infrared rays on the monitoring area A. Adjustment is made so as to coincide with the optical axes 23b and 23d of the light emitting elements 21b and 21d.

  Thereby, the infrared light receiving element 31b has two light receiving regions RPbL and RPbR, and these light receiving regions RPbL and RPbR are infrared spot light SPd by the infrared light emitting element 21d and infrared light by the infrared light emitting element 21b on the monitoring area A, respectively. Superposed with the spot light SPb.

  Thereby, both infrared light emitted from the infrared light emitting elements 21a and 21c is received by one infrared light receiving element 31a, and both infrared light emitted from the infrared light emitting elements 21b and 21d are received by the other infrared light receiving element. Light is received by the element 31b.

  As shown in FIG. 2, the control unit 12 outputs a drive signal to each of the infrared light emitting elements 21a to 21d, and sequentially drives each of the infrared light emitting elements 21a to 21d. Thereby, each infrared light emitting element 21a-21d lights cyclically like 21a-> 21b-> 21c-> 21d-> 21a ..., for example.

  Moreover, the control part 12 always monitors the light reception signal output from each infrared light receiving element 31a, 31b as a light reception signal of the whole light-receiving part 30, and compares it with the preset threshold value of the door opening.

  According to this, for example, when the light receiving level of the light receiving unit 30 exceeds the threshold value when the infrared light emitting element 21b is turned on, it is determined that a person has entered the position of the infrared spot light SPb by the infrared light emitting element 21b. it can.

  In the first embodiment, as described above, the number of the infrared light receiving elements 31 is m2, the division ratio of the second lens system 32 on the light receiving side is n2, and the number of the infrared light emitting elements 21 is determined to be m2 × n2. Therefore, for example, when there are three infrared light receiving elements 31 and a three-divided lens is used for the second lens system 32 on the light receiving side, the number of infrared light emitting elements 21 is nine.

  In other words, for example, if six infrared light emitting elements 21 are used, and if a two-divided lens is used for the second lens system 32 on the light receiving side, the number of infrared light receiving elements 31 may be three. If a three-division lens is used for the second lens system 32 on the side, the number of infrared light receiving elements 31 may be two.

  Next, referring to FIG. 3 and FIG. 4, the automatic door reflection type sensor 1B according to the second embodiment of the present invention will be described. This second embodiment corresponds to claims 1 and 3.

  In the automatic door reflective sensor 1B, the number of infrared light emitting elements 21 is m1, the division ratio of the first lens system 22 on the light emitting side is n1, and the monocular lens 32a having a division ratio of 1 is set on the second lens system 32 on the light receiving side. , The number of the infrared light receiving elements 31 is set to m1 × n1, and the control unit 12 simultaneously drives the m1 infrared light emitting elements 21 and outputs each of the m1 × n1 infrared light receiving elements 31. The received light signal is preferably scanned and monitored alternately in a predetermined order.

  In the example of FIG. 3, the infrared light emitting element 21 of the light emitting unit 20 has two elements (infrared light emitting elements 21 a and 21 b), and the infrared light receiving element 31 of the light receiving unit 30 has four elements (infrared light receiving elements 31 a to 31 d). ), The split lens 22b is used for the first lens system 22 on the light emitting side, and the monocular lens 32a is used for the second lens system 32 on the light receiving side.

  The infrared light emitting elements 21a and 21b and the infrared light receiving elements 31a to 31d are mounted on the circuit board 11 in a horizontal row (in the left-right direction in FIG. 1) at predetermined intervals, and one of the infrared light emitting elements in the light emitting unit 20 is mounted. The infrared light emitted from 21a is divided into infrared light having an optical axis 23aL and infrared light having an optical axis 23aR by a two-divided lens 22b, and two infrared spot lights SPaL and SPaR are emitted from the infrared light emitting element 21a to the monitoring area A. Irradiated.

  Similarly, the infrared light emitted from the other infrared light emitting element 21b in the light emitting unit 20 is divided into infrared light having an optical axis 23bL and infrared light having an optical axis 23bR by the two-divided lens 22b, and the infrared light emitting element 21b. To the monitoring area A is irradiated with two infrared spot lights SPbL and SPbR.

  In contrast, the infrared light receiving elements 31a to 31d have optical axes 23aR, 23bR, 23aL, and 23bL in which the optical axes 33a to 33d shown in chain lines are divided into two of the infrared light emitting elements 21a and 21b on the monitoring area A, respectively. And / or the inclination of the monocular lens 32a of the second lens system 32 and the like are adjusted.

  Thereby, each infrared spot light SPaR, SPbR, SPaL, SPbL by the infrared light emitting elements 21a, 21b overlaps with the spot-like light receiving areas RPa-RPd of the infrared light receiving elements 31a-31d, and emitted from the infrared light emitting element 21a. Infrared light is received by the infrared light receiving elements 31a and 31c, and infrared light emitted from the infrared light emitting element 21b is received by the infrared light receiving elements 31b and 31d.

  As shown in FIG. 4, in this automatic door reflection type sensor 1B, the control unit 12 simultaneously applies drive signals to the two infrared light emitting elements 21a and 21b, and lights the infrared light emitting elements 21a and 21b simultaneously.

  On the other hand, the light receiving signals output from the infrared light receiving elements 31 a to 31 d of the light receiving unit 30 are individually input to the control unit 12. The control unit 12 cyclically monitors and monitors the light reception signals individually input for each of the infrared light receiving elements 31a to 31d in a predetermined order, for example, 31a → 31b → 31c → 31d → 31a.

  According to this, for example, when the light receiving level exceeds the door opening threshold during scanning of the infrared light receiving element 31b, a person is placed at the position of the light receiving region RPb (corresponding to the infrared spot light SPbR) of the infrared light receiving element 31b. It can be determined that an intrusion has occurred.

  In addition, it is possible to monitor each received light signal output from the infrared light receiving elements 31a to 31d in units of infrared spot light by individually monitoring the light receiving signals without cyclic scanning monitoring as described above.

  In the second embodiment, as described above, the number of infrared light receiving elements 31 is determined to be m1 × n1, where m1 is the number of infrared light emitting elements 21 and n1 is the division ratio of the first lens system 22 on the light emitting side. Therefore, for example, when there are three infrared light emitting elements 21 and a three-division lens is used for the first lens system 22 on the light emitting side, the number of infrared light receiving elements 21 is nine.

  In other words, for example, when the number of the infrared light receiving elements 31 is six and the split lens is used for the first lens system 22 on the light emitting side, the number of the infrared light emitting elements 21 may be three, and If a three-divided lens is used for the second lens system 22 on the side, the number of infrared light emitting elements 21 may be two.

  Next, referring to FIGS. 5 and 6, a reflective sensor for an automatic door according to a third embodiment and a fourth embodiment of the present invention will be described. Both the third embodiment and the fourth embodiment correspond to claims 1 and 4. 5 and 6, for convenience, the light emitting unit 20 and the light receiving unit 30 are illustrated separately in FIGS. 5A and 5B. For convenience of drawing, the first and second embodiments are described. The casing, circuit board, control unit, and the like described in the embodiment are not shown.

  With reference to FIGS. 5A and 5B, in the third embodiment, the infrared light emitting element 21 of the light emitting section 20 is composed of two elements (infrared light emitting elements 21a and 21b), and the first lens system 22 on the light emitting side is provided. A three-division lens (compound eye lens) 22c having a division ratio of “3” is used. On the other hand, the infrared light receiving element 31 of the light receiving unit 30 is made of three elements (infrared light receiving elements 31a to 31c), and the second lens system on the light receiving side. A two-divided lens (compound eye lens) 32 b having a division ratio “2” is used as 32.

  As shown in FIG. 5A, the infrared light emitted from one infrared light emitting element 21a in the light emitting unit 20 is divided into three by a three-divided lens 22c, and three infrared spots by the infrared light emitting element 21a are formed in the monitoring area A. Light SPa is irradiated.

  Similarly, the infrared light emitted from the other infrared light emitting element 21b is also divided into three by the three-divided lens 22c, and the three infrared spot lights SPb from the infrared light emitting element 21b are irradiated to the monitoring area A.

  In this way, six infrared spot lights are irradiated to the monitoring area A by the two infrared light emitting elements 21a and 21b. In this case, preferably, the infrared spot light SPa and the infrared light emission by the infrared light emitting element 21a are emitted. Infrared spot light SPb by the element 21b is alternately arranged in the order of SPb → SPa from the left in FIG.

  On the other hand, as shown in FIG. 5 (b), the infrared light receiving element 31a in the light receiving unit 30 has its optical axis divided into two by the two-divided lens 32b. Will have.

  Similarly, since the optical axes of the infrared light receiving elements 31b and 31c are also divided into two by the two-divided lens 32b, the infrared light receiving element 31b has two light receiving regions RPb in the monitoring area A, and the infrared light receiving element 31c is also monitored. The area A has two light receiving regions RPc.

  In this way, six light receiving areas by the three infrared light receiving elements 31a to 31c are set in the monitoring area A. In FIG. 5B, the arrangement order of the infrared light receiving elements 31a to 31c is 31a → 31b from the left. In the case of 31c, the arrangement order of the light receiving regions is preferably RPc → RPb → RPa → RPc → RPb → RPa from the left so that the infrared spot light trains SPb → SPa → SPb → SPa → SPb → SPa overlap each other. To. The correspondence relationship between the infrared spot light and the light receiving area in the third embodiment is shown in Table 1 below.

  As can be seen, the infrared spot light SPa emitted from one infrared light emitting element 21a is applied to the light receiving regions RPb, RPc, and Rpa, and the reflected light is received by the infrared light receiving elements 31a to 31c.

  Similarly, the infrared spot light SPb emitted from the other infrared light emitting element 21b is also applied to the light receiving regions RPc, RPa, and Rpb, and the reflected light is received by the infrared light receiving elements 31a to 31c.

  However, since the same combination does not exist in the combination of the infrared spot light and the light receiving area shown in Table 1, the infrared light emitting elements 21a and 21b are driven alternately, and the light receiving signals output from the infrared light receiving elements 31a to 31c are individually set. By monitoring automatically, a person can be detected in each infrared spot light unit.

  As an example, when the infrared light emitting element 21a is turned on, for example, when the light reception signal of the infrared light receiving element 31c changes from a low level to a high level, in Table 1, the combination of SPa and RPc, that is, the monitoring area in FIG. In A, it can be determined that a person is present at the position of the fourth spot from the left.

  As another example, when the infrared light emitting element 21b is turned on, for example, when the light reception signal of the infrared light receiving element 31b changes from a low level to a high level, in Table 1, the combination of SPb and RPb, that is, in FIG. In the monitoring area A, it can be determined that a person is present at the fifth spot from the left.

  Next, referring to FIGS. 6A and 6B, in the fourth embodiment, the infrared light emitting element 21 of the light emitting unit 20 is composed of four elements (infrared light emitting elements 21a to 21d), and the first lens on the light emitting side. A three-division lens (compound eye lens) 22c having a division ratio of “3” is used for the system 22, and the infrared light receiving element 31 of the light receiving unit 30 is composed of three elements (infrared light receiving elements 31a to 31c). The two-lens system 32 uses a four-divided lens (compound lens) 32d having a division ratio of “4”.

  As shown in FIG. 6A, the infrared rays emitted from the infrared light emitting elements 21a to 21d in the light emitting unit 20 are each divided into three by a three-divided lens 22c. Three infrared spot light SPa by 21a, three infrared spot light SPb by infrared light emitting element 21b, three infrared spot light SPc by infrared light emitting element 21c, and three infrared spot light SPd by infrared light emitting element 21d are irradiated.

  Therefore, when the infrared light emitting elements 21a to 21d are simultaneously turned on, the 12 infrared spot lights are simultaneously irradiated to the monitoring area A. In FIG. 6A, the infrared light emitting elements 21a to 21d are irradiated. When the arrangement order is 21a → 21b → 21c → 21d from the left, the arrangement order of the infrared spot lights is preferably the repetition of SPd → SPc → SPb → SPa from the left.

  On the other hand, as shown in FIG. 6B, the infrared light receiving element 31a in the light receiving unit 30 is divided into four light receiving regions RPa in the monitoring area A because its optical axis is divided into four by a four-divided lens 32b. Will have.

  Similarly, since each optical axis of the infrared light receiving elements 31b and 31c is also divided into four by the four-divided lens 32d, the infrared light receiving element 31b has four light receiving regions RPb in the monitoring area A, and the infrared light receiving element 31c is also monitored. The area A has four light receiving regions RPc.

  In this way, 12 light receiving areas by the three infrared light receiving elements 31a to 31c are set in the monitoring area A. In FIG. 6B, the arrangement order of the infrared light receiving elements 31a to 31c from the left is 31a → In the case of 31b → 31c, the arrangement order of these light receiving areas is preferably repeated from the left from RPc → RPb → RPa so as to overlap with the repetition of the infrared spot light trains SPd → SPc → SPb → SPa. The correspondence relationship between the infrared spot light and the light receiving area in the fourth embodiment is shown in Table 2 below.

  As can be seen, the infrared spot light SPa emitted from the infrared light emitting element 21a is applied to the light receiving regions RPc, RPb, and Rpa, and the reflected light is received by the infrared light receiving elements 31a to 31c.

  Similarly, the infrared spot light SPb emitted from the infrared light emitting element 21b is incident on the light receiving areas RPa, RPc, Rpb, the infrared spot light SPc emitted from the infrared light emitting element 21c is incident on the light receiving areas RPb, RPa, Rpc, and The infrared spot light SPd emitted from the infrared light emitting element 21d is applied to the light receiving regions RPc, RPb, and Rpa, and each reflected light thereof is received by the infrared light receiving elements 31a to 31c.

  As described above, the infrared light emitted from the infrared light emitting elements 21a to 21d is received by the infrared light receiving elements 31a to 31c, respectively. However, in the combination of the infrared spot light and the light receiving area shown in Table 2, the same combination is used. Does not exist.

  Therefore, also in the fourth embodiment, the infrared light emitting elements 21a to 21d are alternately scanned and driven (scanning lighting), and the light receiving signals output from the infrared light receiving elements 31a to 31c are individually monitored, A person can be detected in units of infrared spot light.

  As an example, when the infrared light emitting element 21a is turned on, for example, when the light reception signal of the infrared light receiving element 31a changes from a low level to a high level, in Table 1, the combination of SPa and RPa, that is, the monitoring area in FIG. In A, it can be determined that a person is detected at the rightmost spot light position.

  As another example, when the infrared light emitting element 21b is turned on, for example, when the light reception signal of the infrared light receiving element 31c changes from a low level to a high level, in Table 1, the combination of SPb and RPc, that is, in FIG. In the monitoring area A, it can be determined that a person is present at the seventh spot from the left.

  As described above, according to the third and fourth embodiments, the number of elements can be further reduced as compared with the first and second embodiments while enabling detection in units of each infrared spot light.

The schematic diagram which shows the structure of the reflective sensor of the automatic door use which concerns on 1st Embodiment of this invention. The schematic diagram which shows the control part in the said 1st Embodiment. The schematic diagram which shows the structure of the reflection type sensor for the automatic door use which concerns on 2nd Embodiment of this invention. The schematic diagram which shows the control part in the said 2nd Embodiment. The schematic diagram which shows the structure by the side of (a) light emission part of the reflection type sensor which concerns on 3rd Embodiment of this invention, (b) The light reception part side. (A) The schematic diagram which shows the structure by the side of the light emission part of the reflective sensor which concerns on 4th Embodiment of this invention, (b) The schematic diagram which shows the structure by the side of a light-receiving part. The schematic diagram which shows the structure of the reflection type sensor for automatic doors which concerns on a 1st prior art example. The schematic diagram which shows the example which made the monitoring area multi-line arrangement. The schematic diagram which shows the structure of the reflection type sensor for automatic doors which concerns on a 2nd prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1A, 1B Reflective sensor for automatic doors 10 Housing | casing 11 Circuit board 12 Control part 20 Light emission part 21 (21a-21d) Infrared light emitting element 22 1st lens system 22a Monocular lens 22b Two-division lens 23c Three-division lens 30 Light-receiving part 31 (31a to 31d) Infrared light receiving element 32 Second lens system 32a Monocular lens 32b Two-division lens 32d Four-division lens A Monitoring area

Claims (4)

A light emitting unit including an infrared light emitting element, a light receiving unit including an infrared light receiving element, and a control unit that outputs a drive signal to the infrared light emitting element and generates a control signal based on the light reception signal output from the infrared light receiving element A plurality of infrared spot lights are irradiated in a predetermined arrangement to the monitoring area via the first lens system on the light emission side from the light emitting unit, with a predetermined floor surface as a monitoring area, In the reflective sensor that receives the reflected light from the monitoring area at the light receiving unit via the second lens system on the light receiving side,
The number of the infrared light emitting elements on the light emitting unit side is m1, the division ratio of the first lens system on the light emitting side is n1 (m1, n1 are positive integers of 1 or more), and the infrared light receiving element on the light receiving unit side. M2 and the division ratio of the second lens system on the light receiving side is n2 (m2, n2 are positive integers of 1 or more, where m1 ≠ m2, n1 ≠ n2),
The relationship between the number m1 of the infrared light emitting elements and the division ratio n1 of the first lens system on the light emitting side and the number m2 of the infrared light receiving elements and the division ratio n2 of the second lens system on the light receiving side is expressed as m1 × n1. = M2 × n2 (where n1 / n2, where n1> n2, and n2 / n1 where n1 <n2 is divisible, and even when each of the above divided values is not divisible, n1 and n2 are other than 1) A reflection type sensor characterized in that the number is not included).   When a monocular lens having a division ratio of 1 is used for the first lens system on the light emitting side, the control unit alternately scans and drives the m1 infrared light emitting elements in a predetermined order, and the m2 infrared light receiving elements. The reflection type sensor according to claim 1, wherein the light reception signal output from the element is monitored.   When a monocular lens having a division ratio of 1 is used for the second lens system on the light receiving side, the control unit simultaneously drives the m1 infrared light emitting elements and outputs each light received from the m2 infrared light receiving elements. The reflective sensor according to claim 1, wherein the signal is monitored.   A compound eye lens in which the number m1 of the infrared light emitting elements and the number m2 of the infrared light receiving elements are both 2 or more, and each of the first lens system on the light emitting side and the second lens system on the light receiving side has a division ratio of 2 or more. When the control unit is used, the control unit alternately scans and drives the m1 infrared light emitting elements in a predetermined order, and individually monitors the light reception signals output from the m2 infrared light receiving elements. The reflective sensor according to claim 1.

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