JP2018091688A - Object detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance detection performance of an object detection device that does not depend on an installation environment of a primary luminance distribution detection device when grasping the presence or absence, a position or an action state of an object and to make a monitoring object space freely divided when grasping the presence or absence, the position or the action state of the object.SOLUTION: An object detection device includes: determination means 7 for determining the presence or absence of an object, a position and an action state in a monitoring object space based on a light intensity signal from each light receiving element of a line sensor 1; and display means 12 for reporting a determination result. The determination means 7 includes: a background value storage means 8 for storing a background value signal; actual measurement value storage means 9 for storing the light intensity signal detected by each light receiving element of the line sensor 1 for each predetermined time as time-series data; and display control means 11 for transmitting display control information to the display means 12 based on a CPU 10 for creating report information by determining the presence or absence, the position and the action state of the object by the inter-frame differential method or the background differential method and the report information.SELECTED DRAWING: Figure 9

Description

  The present invention accurately grasps the presence, position, or operation state of a target person or target object (hereinafter referred to as “target object” together) in a monitoring target space using a one-dimensional luminance distribution detection device. It is related with the target object detection apparatus which can do.

To grasp the presence, position, or operating state of an object in the monitoring target space, a two-dimensional image using a normal camera is used. However, its use in homes is restricted in terms of privacy protection. Yes.
Therefore, prior to the present invention, the present inventors installed a rod lens, a slit, and a line sensor for the purpose of grasping the presence / absence, position, or operation state of an object in the monitoring target space without using a two-dimensional image. A one-dimensional luminance distribution detection device was proposed.
Patent Document 1 (Japanese Patent Application Laid-Open No. 2015-163868) is one of those proposals. The line sensor (1) is installed at a position facing the monitoring target space (3), and the line sensor (1 ) And a slit (2) intersecting with the extension plane (5) extending to the monitoring target space side, and based on light intensity signals from a plurality of light receiving elements arranged in the longitudinal direction of the line sensor (1) The presence / absence of an object in the monitoring target space (3) or the position of the object in the direction along the longitudinal direction of the line sensor (1) is determined (particularly, see FIG. 1).
The presence / absence and position of the object are determined by a method of verifying the difference between the ADU value when there is no object in the monitoring target space (3) and the ADU value when the object exists, that is, the background This is done by the difference method (see in particular paragraphs 0028-0032 and FIGS. 3-6).
Therefore, depending on the installation environment of the line sensor, the brightness distribution of the background may change due to changes in the brightness of the background or ambient light, and the target object may not be detected accurately.

  In addition, as described in Patent Document 2 (Japanese Patent No. 3625440), when an object is detected from an image captured by a camera, the background difference method and the interframe difference method are used, the background difference method and the frame The inter-difference method has advantages and disadvantages. For example, it is conventionally known that the intruding object detection performance can be improved by applying the inter-frame difference method in front of the camera screen and the background difference method in the back of the screen. (See especially paragraphs 0002, 0009 and 0017).

Japanese Patent Laying-Open No. 2015-163868 Japanese Patent No. 3625440

However, when the presence / absence, position, or operation state of an object is grasped by a one-dimensional luminance distribution detection device using a slit or rod lens and a line sensor, the background difference method and the interframe difference method are used together or separately. That hasn't been done so far.
Further, as described in Patent Document 2, even if an inter-frame difference method is applied in front of the screen and a background difference method is applied in the back of the screen, the one-dimensional luminance distribution detection device described in Patent Document 1 moves horizontally. As shown in FIG. 1 (same as FIG. 1 of Patent Document 1), the line sensor (1) is disposed horizontally when grasping the operation state of the target object to be observed, and extends along the top and bottom of the monitoring target space (3). All the light from the lines (for example, R1-R2-R3 lines) is incident on one light receiving element, and the monitored space (3) cannot be divided and processed in the vertical direction.
Furthermore, even when trying to process using a plurality of one-dimensional luminance distribution detection devices, the detection range in the vertical direction of the one-dimensional luminance distribution detection device is the length of the line sensor (1) and slit (2) and the line sensor (1 ) And the slit (2), the monitored space (3) cannot be freely divided vertically.

  The first object of the present invention is to improve the detection performance of the object detection device regardless of the installation environment of the one-dimensional luminance distribution detection device when grasping the presence / absence, position, or operation state of the object. In order to grasp the presence / absence, position, or operation state of an object using a plurality of one-dimensional luminance distribution detection devices, a second object is to allow a space to be monitored to be freely divided. Is.

The invention according to claim 1 is an object detection apparatus for monitoring presence / absence, position, or operation state of an object in a monitoring object space using a one-dimensional luminance distribution detection apparatus having a slit or rod lens and a line sensor. And
When there is no object in the monitoring target space, background value storage means for acquiring and storing the light intensity detected by each light receiving element of the one-dimensional luminance distribution detection device;
Actual value storage means for acquiring and storing light intensity detected by each of the light receiving elements at least at the present time and a predetermined time before the present time;
An inter-frame difference determination that determines an operation state of an object in the monitoring target space and outputs inter-frame difference determination result information based on the current time stored in the actual measurement value storage means and the light intensity at a predetermined time before the current time. Means,
Based on the background light intensity stored in the background value storage means and the current light intensity stored in the measured value storage means, the presence / absence, position or operating state of the object in the monitoring target space is determined, and a background difference Background difference discrimination means for outputting discrimination result information;
Presence / absence of an object in the monitoring target space based on one or both of the inter-frame difference determination result information output from the inter-frame difference determination means and the background difference determination result information output from the background difference determination means The object monitoring information notifying means for notifying the position or the operation state is provided.

The invention according to claim 2 is the object detection apparatus according to claim 1, wherein the object monitoring information notification means includes:
When the inter-frame difference determination result information output from the inter-frame difference determination means includes information indicating the motion of the target, the target in the monitoring target space is based on the inter-frame difference determination result information. Inform the operating status of
When the inter-frame difference determination result information output from the inter-frame difference determination means does not include information indicating the motion of the object, based on the background difference determination result information output from the background difference determination means, The presence / absence, position, or operation state of an object in the monitoring target space is notified.

The invention according to claim 3 is the object detection device according to claim 1, wherein the one-dimensional luminance distribution detection device includes a first one-dimensional luminance distribution detection device and a second one-dimensional luminance distribution detection device. And
The inter-frame difference discriminating means discriminates the operation state of the object in the monitoring target space based on the light intensity detected by each light receiving element of the first one-dimensional luminance distribution detecting device, and the inter-frame difference discriminating result information Output
The background difference determination means determines the presence / absence, position, or operating state of an object in the monitoring target space based on the light intensity detected by each light receiving element of the second one-dimensional luminance distribution detector, and determines the background difference. Output result information,
The object monitoring information notification unit is configured to detect an object in the monitoring target space based on the inter-frame difference determination result information output from the inter-frame difference determination unit and the background difference determination result information output from the background difference determination unit. The presence / absence, position, or operating state of an object is reported.

  The invention according to claim 4 is the object detection device according to claim 3, wherein at least one of the first one-dimensional luminance distribution detection device and the second one-dimensional luminance distribution detection device is the slit or the rod lens. The light receiving range control means for controlling the light receiving range is provided.

  According to the object detection apparatus of the first aspect of the invention, the operation state of the object in the monitoring target space is determined based on the current time and the light intensity at a predetermined time before the current time, and the interframe difference determination result information is output. Combined use of inter-frame difference determination means and background difference determination means for determining the presence / absence, position or operating state of an object in the monitoring target space based on the background light intensity and the current light intensity, and outputting background difference determination result information The object monitoring information notification means notifies the presence / absence, position, or operation state of the object in the monitoring target space based on one or both of the inter-frame difference determination result information and the background difference determination result information. The detection performance of the object can be improved regardless of the installation environment of the original luminance distribution detection device.

In the object detection device according to the second aspect of the invention, the object monitoring information notification means includes a case where the interframe difference determination result information output from the interframe difference determination means includes information indicating the operation of the object. Is based on the inter-frame difference determination result information, informs the operation state of the object in the monitoring target space, and the inter-frame difference determination result information output from the inter-frame difference determination means includes information indicating the operation of the object. If not, the presence / absence, position, or operation state of the object in the monitoring target space is notified based on the background difference determination result information output from the background difference determination means.
That is, according to the object detection device of the invention of claim 2, in addition to the effect of the invention of claim 1, notification based on inter-frame difference determination result information that is not easily affected by changes in background brightness or ambient light Therefore, even when the installation environment of the one-dimensional luminance distribution detection device is an environment in which the background value is likely to change, it is possible to accurately detect the operation state of the object.

In the object detection device of the invention according to claim 3, the one-dimensional luminance distribution detection device has a first one-dimensional luminance distribution detection device and a second one-dimensional luminance distribution detection device, and the inter-frame difference determination means is Based on the light intensity detected by each light receiving element of the first one-dimensional luminance distribution detection device, the operation state of the object in the monitoring target space is determined, and the background difference determination means is provided for the second one-dimensional luminance distribution detection device. Based on the light intensity detected by each light receiving element, the presence / absence, position, or operation state of the object in the monitoring target space is determined, and the object monitoring information notification unit includes the inter-frame difference determination result information and the background difference determination result information. Based on this, the presence / absence, position, or operation state of the object in the monitoring target space is notified.
That is, according to the object detection apparatus of the invention according to claim 3, in addition to the effect of the invention according to claim 1, the first object for the monitoring target space that is easily affected by changes in the brightness of the background and the disturbance light. For a monitoring target space that is less susceptible to changes in background brightness and ambient light using a one-dimensional luminance distribution detection device, the second one-dimensional luminance distribution detection device is used to determine whether there is an object in the monitoring target space, Since the notification is performed by detecting the position or the operation state, the detection performance of the object detection device can be further improved.

  According to the object detection device of the invention of claim 4, in addition to the effect of the invention of claim 3, at least one of the first one-dimensional luminance distribution detection device and the second one-dimensional luminance distribution detection device is a slit or Since the light receiving range control means for controlling the light receiving range of the rod lens is provided, when the presence / absence, position or operation state of the target object is grasped using two one-dimensional luminance distribution detection devices, the monitoring target space is accurately determined. Can be divided.

The figure which shows the relationship of the light which injects into the line sensor 1 from the line sensor 1, the slit 2, and the monitoring object space 3 of the target object detection apparatus which concerns on Example 1. FIG. FIG. 3 is a horizontal sectional view of the line sensor 1, the slit 2, and the monitoring target space 3 according to the first embodiment. The graph which shows the light intensity detected by each light receiving element of the line sensor 1 which concerns on Example 1, when the target object does not exist in the monitoring object space 3. FIG. The graph which shows the light intensity detected by each light receiving element of the line sensor 1 which concerns on Example 1, when a target object is located in the right side of the monitoring object space 3. FIG. 6 is a graph showing the light intensity detected by each light receiving element of the line sensor 1 according to the first embodiment when the object is located in the center of the monitoring target space 3. The graph which shows the light intensity detected by each light receiving element of the line sensor 1 which concerns on Example 1 when a target object is located in the left side of the monitoring object space 3. FIG. 6 is a graph showing the inter-frame difference value of the light intensity when the object moves from the position of FIG. 4 to the position of FIG. 5. The graph which shows the inter-frame difference value of light intensity when a target object moves to the position of FIG. 6 from the position of FIG. 1 is a diagram illustrating an overall configuration of an object detection device according to Embodiment 1. FIG. The figure which shows the relationship of the light which injects into the line sensors 1a and 1b from the line sensors 1a and 1b, the slits 2a and 2b, and the monitoring object space 3 of the target object detection apparatus concerning Example 2. FIG. FIG. 6 is a diagram illustrating an overall configuration of an object detection device according to a second embodiment.

  Embodiments of the present invention will be described below with reference to Examples 1 and 2.

FIG. 1 shows a relationship between light incident on the line sensor 1 from the line sensor 1, the slit 2, and the monitoring target space 3 of the object detection apparatus according to the first embodiment.
The line sensor 1 has a length of 28.5 mm and 2068 light receiving elements arranged in the longitudinal direction, and is installed almost horizontally.
The slit 2 is formed by forming an elongated hole having a length of 11 mm and a width of 1 mm parallel to the side of the flat plate having a width of 40 mm, a height of 25 mm, and a thickness of 1 mm, and extending in the longitudinal direction of the line sensor 1. 4 and intersects the extension plane 5 extending horizontally toward the monitoring target space 3 perpendicularly. That is, the slit 2 is arranged in the vertical direction.
Further, the extension plane 5 and the slit 2 intersect at the center of the slit 2.

  As shown in FIG. 1, when it is assumed that the back surface of the monitoring target space 3 is a flat wall 6, the monitoring target space 3 whose luminance can be measured by the line sensor 1 is the left end of the line sensor 1 and the lower end of the slit 2. A straight line passing through the wall 6, a point L1 where the straight line passing through the right end of the line sensor 1 and the lower end of the slit 2 intersects the wall 6, and a straight line passing through the left end of the line sensor 1 and the upper end of the slit 2 And a straight line passing through the right end of the line sensor 1 and the upper end of the slit 2, a point L 3 intersecting the wall 6, a space surrounded by six points, the lower end of the slit 2 and the upper end of the slit 2.

As shown in FIG. 2, the width X and height Y of the wall 6 of the monitoring target space 3 are set such that the length of the line sensor 1 is x, the length of the slit 2 is y, the distance between the line sensor 1 and the slit 2 is d, When the distance between the slit 2 and the wall 6 is D and the width s of the slit 2 is ignored, it is expressed by the following equation.
X = x × D / d
Y = y × D / d

Note that the detectable width X is also related to the width s of the slit 2 and the thickness t of the flat plate. If the detectable angle is θ (deg), θ and X can be obtained by the following equations.
θ = arctan {d / (x / 2 + s / 2)}
However, the lower limit is arctan (t / s)
X = 2 × D × tan (90 ° −θ)
Here, in Example 1, since d = 15.47 mm, t = 1 mm, and x = 28.5 mm, when these values are substituted into the above equation and s = 0, θ = 47 °. Become.
Since s at which arctan (1 / s) is 47 ° is calculated as 0.92 mm, the detection angle θ does not reach the lower limit if s is 0.92 mm or more. Therefore, in Example 1, the slit width is set to 1 mm.

  When there is no object in the monitoring target space 3, the light intensity incident on the light receiving element S1 at the left end of the line sensor 1 is reflected by the wall on the line from R1 through R2 to R3 as shown in FIG. The intensity of light incident on the light receiving element S2 in the center of the line sensor 1 is the intensity of light reflected by the wall on the line from C1 to C2 in FIG. Similarly, the light intensity incident on the light receiving element S3 at the right end of the line sensor 1 is the sum of the intensities of the light reflected by the wall on the line from L1 to L2 to L3 in FIG.

FIG. 3 is a graph of ADU values corresponding to the amount of charge generated in each light receiving element when there is no object in the monitoring target space 3. The horizontal axis indicates the number of the light receiving element from the left side, and the unit of the vertical axis is ADU.
Since the amount of charge generated in the light receiving element varies depending on the intensity of incident light, FIG. 3 can be said to be a graph showing the light intensity detected by each light receiving element.

FIG. 4 is a graph similar to FIG. 3 when an object is present on the right side of the monitoring target space 3.
Usually, since the reflectance of the object is lower than that of the wall, as can be seen from FIG. 1, when the object is present on the right side of the monitoring target space 3, the line sensor corresponding to the position where the object is present. The light intensity detected by the light receiving element on the left side of 1 will be lowered.
Therefore, the ADU value is lower than the graph of FIG. 3 indicated by a dotted line in a part on the left side of the graph.

FIG. 5 is a graph similar to FIG. 3 when an object exists in the center of the monitoring target space 3.
In this case, the ADU value is lower than the graph of FIG. 3 indicated by a dotted line in the center of the graph.

FIG. 6 is a graph similar to FIG. 3 when an object is present on the left side of the monitoring target space 3.
In this case, the ADU value is lower than the graph of FIG. 3 indicated by a dotted line in a part on the right side of the graph.

4 to 6, depending on where the object is present in the left-right direction of the monitoring target space 3, the ADU value of the portion corresponding to the position is lowered, but the object emits light or If the reflectance is high, the ADU value may be higher than the graph of FIG.
However, in any case, if there is an object, some variation occurs in the graph of FIG. 3, so the ADU value (background value) and the measured ADU value (actual value) in the graph of FIG. ), The location of the object in the left-right direction of the monitoring target space 3 can be determined.
In the first embodiment, since the sum of the light intensity in the vertical direction of the monitoring target space 3 is detected by each light receiving element, when the standing object falls down and lies down, the horizontal direction is limited. From the state where the ADU value of the position is very low, the ADU value of the position where the object in the left-right direction is tilted changes to a slightly low state. And by grasping | ascertaining such a change of ADU value, it can also be discriminate | determined that the target object changed from the standing state to the lying state.

  The above description is about the background difference method for verifying the difference between the background value and the actual measurement value. However, when the background value is easy to change, the actual measurement value is stored in time series. The operation state of the object can be detected more accurately by using the inter-frame difference method for verifying the inter-frame difference value between the current ADU value and the ADU value measured immediately before.

For example, when the object moves from the right side to the left side in the monitoring target space 3 in FIG. 1, the ADU value changes in the order of FIG. 4, FIG. 5, and FIG. 4 and the ADU value in FIG. 4 are obtained as a graph of the inter-frame difference value shown in FIG. 7. FIG. 6 is the current graph, FIG. 5 is immediately before, and the ADU value in FIG. 6 and the ADU value in FIG. If a difference is taken, it will become a graph of the difference value between frames shown in FIG.
In this example, the position where the inter-frame difference value is negative corresponds to the position immediately before the object, and the position where it is positive corresponds to the current position of the object.
That is, it can be seen from FIG. 7 that the object has moved from the right position toward the center and from FIG. 8, the object has moved from the center position to the left position.

However, in the inter-frame difference method, when the object is stationary, the difference between the current ADU value and the ADU value measured immediately before is 0, so that the object cannot be detected.
Therefore, in such a case, switching is performed so that the presence / absence or position of the object is verified using the background difference method.
In addition, when the position immediately before the object is stationary can be identified by the interframe difference method, when switching to verify the presence or position of the object by the background difference method is significant other than the identified position If a background difference value has occurred, it can be considered that the background luminance has changed. Therefore, if the ADU value is corrected when there is no object in the monitoring target space 3 shown in FIG. Can reduce the effects of

FIG. 9 is a diagram illustrating an overall configuration of the object detection device according to the first embodiment.
The object detection apparatus according to the first embodiment includes a slit 2 that narrows down light from the monitoring target space 3, a line sensor 1 that detects the intensity of light that has passed through the slit 2, and an amount of light received by each light receiving element of the line sensor 1. And a discriminating means 7 for discriminating the presence / absence, position and operating state of the object in the monitoring target space 3 and transmitting information for notification thereof.

  The discrimination means 7 includes a background value storage means 8 for storing a light intensity signal (hereinafter referred to as “background value signal”) detected by each light receiving element of the line sensor 1 when there is no object in the monitoring target space, and a predetermined time. Measured value storage means 9 for storing a light intensity signal (hereinafter referred to as “actually measured value signal”) detected by each light receiving element of the line sensor 1 as time series data for each light receiving element, and time series data for each light receiving element. Whether the object's operation state is determined by the inter-frame difference method, or the presence / absence, position, and operation state of the object are determined by the background difference method based on the background value signal and the measured value signal at the temporary point. The CPU 10 generates notification information based on the determination results, and the display control unit 11 transmits display control information to the display unit 12 based on the notification information from the CPU 10.

The display unit 12 receives display control information from the display control unit 11 and displays information about the presence / absence, position, and operation state of the object, and may be provided together with the object detection device, You may provide in the position away from the target object detection apparatus.
The display device 12 displays the presence / absence, position, and operation state of the object, and the display mode includes (1) display with characters and symbols, and (2) area display indicating the monitoring target space 3, The area display includes a visual display for displaying an image according to the presence or absence and position of an object, and (3) a display in which a light intensity signal is graphed.
Then, one or a plurality of displays may be appropriately selected from these display modes according to the needs of the user and displayed.

Further, since the discriminating means 7 has an actual value storage means 9, by adding an instruction input means for the discriminating apparatus 7, information on the presence / absence, position, and operating state of the object at a past designated time can be obtained. It can also be displayed on the display means 12.
Furthermore, the operation state of the object can be traced by continuously displaying the presence / absence and position of the object at a predetermined time before or after the specified time.
In such a case, if the predetermined time is long, the operation state of the object over a long time can be tracked in a short time, and conversely, if the predetermined time is short, the details of the operation state of the object at the time when the user particularly wants to watch. Tracking can be performed.

FIG. 10 shows the relationship between the line sensors 1a and 1b, the slits 2a and 2b, and the light incident on the line sensors 1a and 1b from the monitoring target space 3 in the object detection apparatus according to the second embodiment.
The object detection apparatus according to the second embodiment has a one-dimensional luminance distribution detection apparatus arranged one above the other. The upper one-dimensional luminance distribution detection apparatus includes a line sensor 1a and a slit 2a, and the luminance distribution of the background is the same. The lower one-dimensional luminance distribution detection device is arranged toward a space that easily changes, and has a line sensor 1b and a slit 2b, and is arranged toward a space where the luminance distribution of the background is difficult to change.
The slits 2a and 2b divide the monitoring target space 3 appropriately in the vertical direction so that the line sensors 1a and 1b can receive light only from a desired space (the upper end and / or the lower end). Can be adjusted.
Each one-dimensional luminance distribution detection device has a groove on the lower edge surface and a protrusion on the upper edge surface so that they can be combined vertically.
Other configurations are the same as those of the object detection apparatus according to the first embodiment shown in FIG.

FIG. 11 is a diagram illustrating the overall configuration of the object detection device according to the second embodiment.
In addition, since it is the structure similar to the target object detection apparatus which concerns on Example 1 except having two slits and a line sensor, the same number is used except a slit and a line sensor.
The object detection apparatus according to the second embodiment includes a slit 2a that narrows down light from the monitoring target space 3 whose luminance distribution is likely to change, a line sensor 1a that detects the intensity of light that has passed through the slit 2a, and the luminance distribution changes. The slit 2b for narrowing the light from the monitoring target space 3 that is difficult to perform, the line sensor 1b for detecting the intensity of the light that has passed through the slit 2b, and the light intensity signal corresponding to the amount of light received by each light receiving element of the line sensors 1a and 1b Further, a determination unit 7 is provided for determining the presence / absence, position, and operation state of an object in the monitoring target space 3 and transmitting information for performing the notification.

  The discriminating means 7 includes a background value storage means 8 for storing light intensity signals (background value signals) detected by the light receiving elements of the line sensors 1a and 1b when there is no object in the monitoring target space, and a line for each predetermined time. Actual value storage means 9 for storing light intensity signals (actual value signals) detected by the light receiving elements of the sensors 1a and 1b as time series data for each light receiving element, and inter-frame differences based on the time series data for each light receiving element The operation state of the object is determined by the method, or the presence / absence, position and operation state of the object are determined by the background difference method based on the background value signal and the measured value signal at the temporary point. CPU 10 that creates notification information based thereon, and display control means 11 that transmits display control information to display means 12 based on the notification information from CPU 10.

In the second embodiment, since the upper one-dimensional luminance distribution detection device is arranged toward a space where the luminance distribution of the background is likely to change, the object discrimination based on the light intensity signal detected by the line sensor 1a is performed. In the normal difference method between frames, when the motion state of the object cannot be determined by the inter-frame difference method or when it cannot be determined, the background difference method is switched to determine the presence / absence, position and motion state of the object.
In addition, since the lower one-dimensional luminance distribution detection device is arranged toward a space where the luminance distribution of the background is difficult to change, the background subtraction method is used in the determination of the object based on the light intensity signal detected by the line sensor 1b. Is used to determine the presence / absence, position, and operation state of the object.
The display control means 11, the display device 12, and the display mode on the display device 12 are the same as those of the object detection device according to the first embodiment.

The modification regarding the target object detection apparatus of Example 1 and 2 is listed.
(1) In the first and second embodiments, the one-dimensional luminance distribution detection device having the slit 2 (in the second embodiment, the slits 2a and 2b) is used. However, instead of the slit, a rod lens may be used. A slit and a rod lens may be selected accordingly.
When the slit and the rod lens can be selected, a mounting member is provided on the back side of the slit so that the rod lens and the cover body that can transmit only visible light or only infrared light can be detachably held. Alternatively, a rod lens may be provided adjacent to the slit and either one may be shielded.

(2) In the first and second embodiments, the line sensor 1 (line sensors 1a and 1b in the second embodiment) is arranged in the horizontal direction, and the slit 2 (slits 2a and 2b in the second embodiment) is arranged in the vertical direction. However, depending on the use environment (for example, when the object moves up and down), the line sensor may be arranged in the vertical direction and the slit may be arranged in the horizontal direction.
(3) In the first and second embodiments, the line sensor 1 (line sensors 1a and 1b in the second embodiment) and the slit 2 (slits 2a and 2b in the second embodiment) are arranged independently. A support member may be provided to support the device so that a predetermined positional relationship is maintained.
In such a case, the line sensor and the slit can be easily placed in an appropriate positional relationship by arranging the support member at an appropriate position.
In particular, in the second embodiment, it is better to provide an adjustment member that can adjust the positional relationship between the line sensor and the slit so that the line sensors 1a and 1b can receive light only from a desired space.

(4) The actual measurement value storage means 9 of the first and second embodiments sequentially applies the actual measurement value signals detected by the respective light receiving elements of the line sensor 1 (in the second embodiment, the line sensors 1a and 1b) at predetermined time intervals. However, it is sufficient if it can store at least the current value and the measured value signal for a predetermined time before the current time for each light receiving element.
In addition, when the time series data exceeds the capacity of the actual value storage means 9, new data can be stored by deleting old data or thinning out time series data after a certain period of time. .
(5) In the first and second embodiments, the presence / absence, position, and operation state of the object are reported by the display unit 12, but a speaker may be provided instead of or in addition to the display unit 12.
In such a case, sound notification can be performed instead of or in addition to display notification.

(6) In the second embodiment, it is assumed that there is a space where the luminance distribution of the background is likely to change above the monitoring target space 3, and there is a space where the luminance distribution of the background is difficult to change below the monitoring target space 3. Two one-dimensional luminance distribution detection devices are arranged on the upper and lower sides, and in the discrimination of an object based on the light intensity signal detected by the line sensor 1a, the interframe difference method is normally used, and based on the light intensity signal detected by the line sensor 1b. Although the background subtraction method was used in the discrimination of the object, the two one-dimensional luminance distribution detection devices may be arranged on the left and right according to the situation of the monitoring target space 3, and each of the intersecting surfaces You may arrange | position so as to oppose.
Further, three or more one-dimensional luminance distribution detection devices may be arranged.

(7) In the second embodiment, the lengths (height of the upper end and / or the lower end) of the slits 2a and 2b of the one-dimensional luminance distribution detector can be adjusted. However, the length may not be adjustable. .
If the lengths of the slits 2a and 2b cannot be adjusted, the distance between the slit 2a and the line sensor 1a or the slit 2b and the line sensor 1b is adjusted to appropriately divide the monitoring target space 3 in the vertical direction. You can do that.
(8) In the one-dimensional luminance distribution detection device of Example 2, grooves are formed on the lower edge surface and protrusions are formed on the upper edge surface so as to be combined vertically, but grooves and protrusions are formed. However, other connecting means may be used in place of the groove or the protrusion.
Further, when other connecting means are used, it is better that the positional relationship between the two one-dimensional luminance distribution detection devices can be changed as appropriate.

DESCRIPTION OF SYMBOLS 1, 1a, 1b Line sensor 2, 2a, 2b Slit 3 Monitoring object space 4, 4a, 4b The straight line 5, 5a, 5b extended in the longitudinal direction of a line sensor The extension plane 6, 6a extended horizontally toward the monitoring object space 3 6b Wall 7 Discriminating means 8 Background value storage means 9 Actual value storage means 10 CPU 11 Display control means 12 Display means d Distance between the line sensor 1 and the slit 2 D Distance between the slit 2 and the wall 6 s Width of the slit 2 x Line sensor 1 length X width of wall 6

Claims (4)

An object detection device for monitoring presence / absence, position, or operation state of an object in a monitoring target space using a one-dimensional luminance distribution detection device having a slit or rod lens and a line sensor,
When there is no object in the monitoring target space, background value storage means for acquiring and storing the light intensity detected by each light receiving element of the one-dimensional luminance distribution detection device;
Actual value storage means for acquiring and storing light intensity detected by each of the light receiving elements at least at the present time and a predetermined time before the present time;
An inter-frame difference determination that determines an operation state of an object in the monitoring target space and outputs inter-frame difference determination result information based on the current time stored in the actual measurement value storage means and the light intensity at a predetermined time before the current time. Means,
Based on the background light intensity stored in the background value storage means and the current light intensity stored in the measured value storage means, the presence / absence, position or operating state of the object in the monitoring target space is determined, and a background difference Background difference discrimination means for outputting discrimination result information;
Presence / absence of an object in the monitoring target space based on one or both of the inter-frame difference determination result information output from the inter-frame difference determination means and the background difference determination result information output from the background difference determination means An object detection apparatus comprising object monitoring information notifying means for notifying a position or an operating state. The object monitoring information notification means includes:
When the inter-frame difference determination result information output from the inter-frame difference determination means includes information indicating the motion of the target, the target in the monitoring target space is based on the inter-frame difference determination result information. Inform the operating status of
When the inter-frame difference determination result information output from the inter-frame difference determination means does not include information indicating the motion of the object, based on the background difference determination result information output from the background difference determination means, The object detection apparatus according to claim 1, wherein the presence / absence, position, or operation state of an object in the monitoring object space is notified. The one-dimensional luminance distribution detection device has a first one-dimensional luminance distribution detection device and a second one-dimensional luminance distribution detection device,
The inter-frame difference discriminating means discriminates the operation state of the object in the monitoring target space based on the light intensity detected by each light receiving element of the first one-dimensional luminance distribution detecting device, and the inter-frame difference discriminating result information Output
The background difference determination means determines the presence / absence, position, or operating state of an object in the monitoring target space based on the light intensity detected by each light receiving element of the second one-dimensional luminance distribution detector, and determines the background difference. Output the result information,
The object monitoring information notification unit is configured to detect an object in the monitoring target space based on the inter-frame difference determination result information output from the inter-frame difference determination unit and the background difference determination result information output from the background difference determination unit. The object detection apparatus according to claim 1, wherein the presence / absence, position, or operation state of an object is reported. At least one of the first one-dimensional luminance distribution detection device and the second one-dimensional luminance distribution detection device includes a light receiving range control unit that controls a light receiving range of the slit or the rod lens. Item 4. The object detection device according to Item 3.

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