JP2001304815A - Position measuring system and position measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position measuring system and a position measuring method capable of measuring the position of a light source by image processing in synchronization with a light emitting timing without transmitting a synchronous signal to the light source. SOLUTION: This position measuring system is provided with a light emitting part including one light source for emitting light in light emitting timing having a designated light emitting cycle and a designated light emitting phase, a photo detecting part for detecting light from the light source and forming an image signal to at least one image frame, and an image processing part for processing the image signal in the processing timing having a designated processing cycle and a designated processing phase to form the position information non the position of the light source, whereby while plural light sources are recognized, image processing time can be shortened to provide a more simple position measuring system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position measuring system for detecting a position of a light source based on image information obtained by receiving pulsed light from at least one light source in synchronization with the pulse light.

[0002]

2. Description of the Related Art Heretofore, as a basic technique for recognizing the position and movement of a person to be measured (object), light from a light source attached to the person to be measured is emitted while being controlled synchronously. Some position measurement systems for receiving light have been proposed. Here, with reference to FIG. 15, a conventional position recognition device 1 disclosed in Japanese Patent Application Laid-Open No. 9-68409 will be described.
01 will be described. As shown in FIG. 15, this position measurement system generally includes three infrared LED light sources 102a, 102b attached to the head and both hands of a measurement subject.
102c, a moving image camera 103 including a CCD sensor (not shown), a microcomputer 104 for calculating two-dimensional position coordinates of an image, and a PC (personal computer) 105 for calculating two-dimensional position coordinates of real space. Have been. The microcomputer 104
Is connected to the light sources 102a, 102b, 102c and the moving image camera 103 by wire.

Next, the circuit configuration and operation of the position recognition device 101 will be described with reference to the block diagram of FIG. The CCD sensor 106 receives light from the light sources 102a, 102b, 102c formed of infrared LED lamps and forms an image signal. CCD sensor 106
Are connected to the microcomputer 104. The microcomputer 104 includes an image memory 107 that temporarily stores an image signal from the CCD sensor 106, an image two-dimensional position coordinate calculator 108 that performs image processing on the image signal to calculate an image two-dimensional position coordinate, and a light emitting area of each light source. Light-emitting area calculation unit 109 that calculates
2b and 102c and a synchronization control unit 110 that supplies a synchronization signal to the image two-dimensional position coordinate calculation unit 108. And
The PC 105 determines the light emitting unit 1 based on the image two-dimensional position coordinates and the position-related data regarding the light emitting area calculated by the image two-dimensional position coordinate calculating unit 108 and the light emitting area calculating unit 109.
Distance calculation unit 1 that calculates the distance between the light receiving unit 103 and the light receiving unit 103
11 and a real space two-dimensional position coordinate calculation unit 112 for calculating real space two-dimensional position coordinates for each of the light sources 102a, 102b, and 102c.

The microcomputer 104 first supplies a synchronization control signal generated by the synchronization control unit 110 to the light sources 102a, 102b, 102c and the image two-dimensional position coordinate calculation unit 108. Then, the light sources 102a, 102
b and 102c are alternately (with different phases) at a constant cycle
It is controlled to emit light. The CCD sensor 106 receives light from the light sources 102a, 102b, 102c,
When the frame rate is 60 Hz, 6
An image signal of zero image frames is formed. The image memory 107 temporarily stores an image signal for each of these image frames. On the other hand, the image two-dimensional position coordinate calculator 108 to which the synchronization signal is supplied is configured to process the image signal of the image frame at the timing when the light source emits light. For example, three light sources 102a, 102b, 1
So that 02c emits light shifted by 1/3 second per second,
When the control is performed using the synchronization signal, the image two-dimensional position coordinate calculation unit 108 performs one-second intervals (the same cycle as the light source).
The image processing is performed only on the image signal formed when the light source is shifted by 1/3 second (the same phase as each light source). In other words, the synchronization control unit 110 controls the light sources 102a, 102b, 1
02c light emission timing (cycle and phase) and image 2
The light sources 102a and 102a are synchronized so that the processing timing (period and phase) of image processing by the dimensional position coordinate calculation unit 108 is synchronized.
02b and 102c and the image two-dimensional position coordinate calculation unit 108 are controlled synchronously. The image two-dimensional position coordinate calculation unit 108 and the light emission area calculation unit 109 that have been synchronized and controlled in this way.
Calculates the image two-dimensional position coordinates and the light emission area as position-related data. Further, the PC 105 calculates a real space distance between the light emitting unit 102 and the light receiving unit 103 from the image-related two-dimensional position coordinates and the position-related data regarding the light emitting area, and calculates a real space two-dimensional position for each of the light sources 102a, 102b, and 102c. Calculate the coordinates.

[0005] The position recognition device 101 configured as described above.
Is associated with the emission phase of light emission and the processing phase of image processing even if there are a plurality of light sources 102, so that the light sources 102a, 102b, 102c for each image two-dimensional position coordinate
Can be specified (recognized). In addition, the image two-dimensional position coordinate calculation unit 108 can recognize the movement of the light source by tracking the temporal change of the image two-dimensional position with respect to the specific light source. Therefore, in order for the position recognition device 101 to recognize the movement of the light source, it is necessary to always be able to cope with the light source from which light source the image signal to be subjected to image processing is formed.

By the way, even when there is only one light source, the light emission timing of the light source 102 and the processing timing of the image two-dimensional position coordinate calculation unit 108 are controlled by synchronizing them so that Other effects can be enjoyed. That is, the image two-dimensional position coordinate calculation unit 108 only needs to perform image processing on the image signal in the minimum necessary time (the number of image frames).
Image processing time can be reduced. In turn,
Image two-dimensional position coordinate calculator 108 and related PC1
The processing time of the image processing circuit such as 05 is also reduced. Furthermore, power consumption of peripheral image processing circuits including the image two-dimensional position coordinate calculation unit 108 can be minimized. Therefore, this type of position recognition system 101
Even when the light emitting unit 102 has one light source, the light sources 102a and 102
It is extremely preferable to perform image processing at a processing timing synchronized with the light emission timings of b and 102c.

[0007]

However, in order for the light source to emit light using the synchronization signal, it is necessary to transmit the synchronization signal from the position recognition device 101 to the light source 102 by wire or wirelessly. When transmitting the synchronization signal to the light source 102 by wire, for example, the measurement target person
It is necessary to always carry the light source 102 connected to the camera. This significantly inhibits the behavior of the person to be measured and gives a sense of restraint. When a synchronization signal is wirelessly given to the light source 102, the light source 102 receives a wireless signal from the position recognition device 101 and needs an electric circuit (not shown) for driving the light source 102 based on the wireless signal. Such an electric circuit is complicated, expensive and bulky compared to a light source,
Not suitable for mobile phones and bothersome.

Accordingly, it is an object of the present invention to provide a position measurement system that measures the position of a light source by performing image processing in synchronization with a light emission timing without transmitting a synchronization signal to the light source.

[0009]

According to the first aspect of the present invention, a light emitting section including one light source which emits light at a light emission timing having a predetermined light emission cycle and a predetermined light emission phase, A light receiving unit for receiving light and forming an image signal for at least one image frame; and processing the image signal at a processing timing having a predetermined processing cycle and a predetermined processing phase to obtain position information on the position of the light source. And an image processing unit that forms the image data. Thereby, the image processing time can be shortened, and a more simple position measurement system can be provided.

According to the second aspect of the present invention, one light-emitting section including a plurality of (k) light sources that emit light at a predetermined light-emission cycle and light-emission timings having different light-emission phases, and light from the light source is provided. A light receiving unit that receives light and forms an image signal for at least one image frame for each light source; and processes the image signal at a processing timing having a predetermined processing cycle and a plurality of processing phases. An image processing unit that forms position information on the position of the light source can be provided. This makes it possible to shorten the image processing time while recognizing a plurality of light sources, thereby providing a simpler position measurement system.

According to the third aspect of the present invention, a plurality of (k) light-emitting portions including one light source that emits light at a light emission timing having a predetermined light emission cycle and a predetermined light emission phase, and light from the light source And a light receiving unit that forms an image signal for at least one image frame with respect to each light source, and superimposes the image signal with a plurality of element processing timings having a predetermined processing cycle and a predetermined processing phase. And an image processing unit that forms the position information on the position of each light source by performing the processing at the processing timing described above. This makes it possible to shorten the image processing time while recognizing a plurality of light sources, thereby providing a simpler position measurement system.

According to the present invention, the image processing unit divides the processing cycle into a plurality of (n; k ≦ n) phase block periods, and each light receiving phase is included in one phase block period. As a result, the position measurement system can easily recognize a plurality of light sources.

According to the fifth aspect of the present invention, the image processing unit is configured to have the phase block allocating unit that allocates each light receiving phase to an arbitrary phase block period. The position measurement system can arbitrarily specify a light source having a light emission phase.

According to the present invention, since each light receiving phase is located at the center of one phase block period, a position measuring system capable of receiving light with high accuracy can be provided.

According to the seventh aspect of the present invention, the light emission period and the processing period are the same, and the light emitting unit can adjust each light emission phase so that each light emission phase is synchronized with the processing phase. Since it is configured to have the adjustment unit, it is possible to provide a simple position measurement system in which the user can adjust each light emission phase.

According to the present invention, the light emitting cycle and the processing cycle are the same, and the image processing unit can adjust the light receiving phase so that the processing phase is synchronized with each light emitting phase. Since it is configured to have the adjustment unit, it is possible to provide a simple position measurement system in which the user can adjust the processing phase.

According to the ninth aspect of the present invention, the image processing section has the cycle synchronization display section for informing the user whether the light emission cycle and the processing cycle are synchronized, and the light emission section has the light emission cycle. Since the light emitting cycle adjusting unit that can adjust the light emitting cycle is provided so as to be synchronized with the processing cycle, a simple position measurement system that allows the user to adjust the light emitting cycle can be provided.

According to the tenth aspect of the present invention, the image processing section has a cycle synchronization display section for informing the user whether or not the light emission cycle and the processing cycle are synchronized. Is configured to have a light receiving cycle adjustment unit that can adjust the processing cycle so as to synchronize with the light emission cycle. Therefore, a simple position measurement system that allows the user to adjust the processing cycle can be provided.

According to the eleventh aspect of the present invention, the image processing section controls the light emitting cycle and the processing cycle so as to synchronize with each other.
Since the automatic light receiving cycle adjusting unit that automatically adjusts the processing cycle is provided, a simple position measurement system that automatically adjusts the processing cycle can be provided.

According to the twelfth aspect of the present invention, the light emitting section has the light emitting cycle display section for notifying the user of the light emitting cycle value, and the light emitting section has the light emitting cycle adjusting section capable of adjusting the light emitting cycle. , A simple position measurement system that allows the user to adjust the light emission cycle can be provided.

According to the present invention, the image processing section has a processing cycle display section for notifying a user of the processing cycle value, and the image processing section has a processing cycle adjusting section capable of adjusting the processing cycle. With this configuration, it is possible to provide a simple position measurement system that allows the user to adjust the light emission cycle.

According to the fourteenth aspect of the present invention, the image processing section has the phase synchronization display section for informing the user whether or not each light emission phase and the processing phase are synchronized. Since the light emitting phase adjusting section is provided so as to adjust each light emitting phase so that the phase is synchronized with the processing phase, a simple position measuring system in which the user can adjust the light emitting phase can be provided.

According to the fifteenth aspect of the present invention, the image processing section has a phase synchronization display section for informing the user whether or not each light emission phase and the processing phase are synchronized. Since the light receiving phase adjuster is provided so that the processing phase can be adjusted by the user so that the phase is synchronized with each light emission phase, a simple position measurement system that allows the user to adjust the processing phase can be provided.

According to the sixteenth aspect of the present invention, the image processing unit controls the light emission phase and the processing phase so that they are synchronized.
Since the apparatus is configured to have the automatic light receiving phase adjustment unit that automatically adjusts the processing phase, a position measurement system that can automatically adjust the processing phase can be provided.

According to the seventeenth aspect of the present invention, the light emitting section has the light emitting phase display section for notifying the user of the light emitting phase value, and the light emitting section has the light emitting phase adjusting section capable of adjusting the light emitting phase. , A simple position measurement system that allows the user to adjust the light emission phase can be provided.

According to the present invention, the image processing section has a processing phase display section for notifying a user of the processing phase value, and the image processing section has a processing phase adjustment section capable of adjusting the processing phase. With this configuration, it is possible to provide a simple position measurement system that allows the user to adjust the processing phase.

According to the nineteenth aspect of the present invention, since the image processing unit is configured to include the image frame adjusting unit that can adjust the number of image frames corresponding to the image signal to be processed, the user can select the image frame. By adjusting the number, a simple position measurement system capable of adjusting the image processing accuracy can be provided.

According to the twentieth aspect of the present invention, when an image processing unit receives light from a plurality of light sources in one image frame, the image processing unit can specify the light source corresponding to each position information. Because it was configured to have the part 45,
For example, even when image processing is performed on light from a plurality of light sources in the same image frame, the position measurement system can specify a light source.

According to the twenty-first aspect of the present invention, a step of causing one light source to emit light at a light emission timing having a predetermined light emission cycle and a predetermined light emission phase; Forming an image signal for one image frame;
Forming a position information relating to the position of the light source by performing processing at a processing timing having a predetermined processing period and a predetermined processing phase. Thereby, image processing time can be shortened.
It is possible to provide a simpler position measurement method.

According to the twenty-second aspect of the present invention, the step of causing the plurality of (k) light sources to emit light at a light emission timing having a predetermined light emission cycle and a different light emission phase, and receiving light from the light source Forming, for each light source, an image signal for at least one image frame; and processing the image signal at a processing timing having a predetermined processing cycle and a plurality of processing phases to determine a position of each light source. Forming position information, respectively. Accordingly, it is possible to provide a simpler position measurement method that can reduce the image processing time while recognizing a plurality of light sources.

According to the twenty-third aspect of the present invention, the sub-step of causing one light source to emit light at a light emission timing having a predetermined light emission cycle and a predetermined light emission phase comprises a plurality of steps having different light emission periods and light emission phases. For the light sources, simultaneously receiving light from the light sources, forming an image signal for at least one image frame for each light source, A position measurement method comprising: processing a plurality of element processing timings having a predetermined processing phase at a processing timing obtained by superimposing a plurality of processing timings; and forming position information on the position of each light source. As a result, while recognizing multiple light sources,
It is possible to provide a simpler position measurement method capable of shortening the image processing time.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Embodiment 1 of a position measurement system 1 according to the present invention will be described with reference to FIGS. FIG. 1 is a configuration diagram schematically showing a position measurement system 1 according to Embodiment 1 of the present invention. Referring to FIG. 1, the position measurement system 1 generally includes a light emitting unit 10 attached to a measurement subject, a light receiving unit 20 including a moving image camera independent of the light emitting unit 10, and an electrical connection with the light receiving unit 20. And an image processing unit 30 connected to the image processing unit. Further, the position measurement system 1 may include a PC (personal computer) 50 connected to the image processing unit 50.

Here, with reference to FIGS. 2 to 4, light emitting unit 1 of position measuring system 1 according to the first embodiment of the present invention.
0, the light receiving unit 20, the image processing unit 30, and the system circuit configuration of the PC 50 will be described. FIG. 2 is a block diagram illustrating a system circuit configuration of the position measurement system 1.

As shown in FIG. 2, the light emitting section 10 has one light source 12 (for example, an infrared LED lamp) that emits a pulse with a predetermined light emission cycle and a predetermined light emission phase, and a light emission adjustment display panel (box) 13. . As shown in FIG. 3, the light emission adjustment display panel (box) 13 includes a manual light emission cycle adjustment unit 14 and a manual light emission phase adjustment unit 15 (for example, a vertical movement adjustment) that allow a user to adjust the light emission cycle and light emission phase of the light source 12. Switch, see FIG. 3).

As shown in FIG. 2, the light receiving section 20 has a condenser lens (not shown) and a CCD sensor 22 which receives light from a light source and forms an image signal in image frame units. At this time, for example, the CCD sensor 22
It has a frame rate of Hz and can detect an image signal of 60 frames per second.

The image processing section 30 incorporates a microcomputer 40 as shown in FIG. The microcomputer 40 includes an image memory 41 for temporarily storing an image signal from the CCD sensor 22 and an image signal in a predetermined processing phase (image frame) at a predetermined processing cycle in conjunction with a frame rate of the CCD sensor 22. An image two-dimensional position coordinate calculator 42 for image processing and a light emitting area calculator 44 for calculating the light emitting area of the light source 12 are built in, and the image two-dimensional position coordinates and the light emitting area of the light source 12 are calculated. Further, the microcomputer 40 includes an automatic processing cycle adjusting unit 47 and an automatic processing phase adjusting unit 4 for automatically adjusting the processing cycle and the processing phase as described later.
8 is built in.

The image processing section 30 has a processing adjustment display panel 31 connected to a microcomputer 40, as shown in FIG. The image processing unit 30 has the following components on the processing adjustment display panel 31. That is, the image processing unit 30 provides the cycle synchronization display unit 32 with which the user is notified whether the light emission cycle and the light emission phase of the light source 12 are synchronized with the processing cycle and the processing phase of the image two-dimensional position coordinate calculation unit 42, respectively. 4, a phase synchronization display section 33 (for example, an LED indicator, see FIG. 4), a light emission cycle display section 34 for displaying a light emission frequency (period) and a processing frequency (period), and a processing cycle display section 35 (for example, a liquid crystal panel, FIG. ), A manual processing cycle adjustment unit 36 and a manual processing phase adjustment unit 37 (for example, an up / down adjustment switch, see FIG. 4) that allow the user to adjust the processing cycle and the processing phase.
A phase block allocating unit 38 (for example, an up / down adjustment switch, see FIG. 4) for selectively allocating a processing phase to be described later to a phase block period, and an image frame adjusting unit 39 that allows a user to adjust the number of image frames to be subjected to image processing.
(For example, a lifting / lowering adjustment switch, see FIG. 4).

Referring again to FIG. 2, the PC 50 calculates the two-dimensional position coordinates of the image calculated by the two-dimensional image position coordinate calculation unit 42 and the position-related data including the light emission area calculated by the area calculation unit 44. It has a real space two-dimensional position coordinate calculation unit 52 for calculating real space two-dimensional position coordinates, and a distance calculation unit 54 for calculating the distance to the light source.

Next, the basic operation of the position measuring system 1 according to the first embodiment of the present invention will be described with reference to the timing chart of FIG. As shown in the upper timing chart of FIG. 5, the light source 12 emits pulse light at a light emission timing having a predetermined light emission cycle (Te: one cycle interval) and a predetermined light emission phase (light emission time point). At this time, the time (de) of the pulse emission may be adjusted.

The CCD sensor 22 is a light source 1 of the light emitting unit 10.
2 to form an image signal for each image frame. That is, when the frame rate of the CCD sensor 22 is 60 Hz, image signals for 60 image frames are formed per second.

On the other hand, the microcomputer 40 calculates the two-dimensional position coordinates of the image with respect to the position of the light source by performing image processing on this image signal. The image signal extracted and extracted is processed. Specifically, as shown in the lower timing chart of FIG. 5, the microcomputer 40 performs a predetermined processing cycle (Tr:
An image signal from the CCD sensor 22 is processed at a processing timing having one cycle interval) and a predetermined processing phase (processing time). At this time, the processing time (dr) in the processing timing chart depends on the number of image frames for the extracted image signal.

As described above, the microcomputer 40
Does not image-process the image signals for all the image frames, but processes the image signals for the image frames extracted by periodically decimating, so that the power consumption of the microcomputer 40 is minimized and the PC
The peripheral arithmetic processing circuits such as 50 can be greatly simplified.

Further, as shown in FIG. 6 which is a partially enlarged view of the timing chart of FIG. 5, the time interval (processing time (dr)) at which the microcomputer 40 performs image processing, that is, the number of image frames is adjusted by processing adjustment. It is preferable that the user can make adjustments using the image frame adjustment unit 39 on the display panel 31. If the number of image frames is large, the two-dimensional position coordinates of the image are formed based on many image signals, so that the accuracy or reliability is improved. However, on the other hand, if the number of image frames is small, the image processing time of the microcomputer 40 is shortened, and power consumption can be further reduced.

Next, a more detailed operation of the microcomputer 40 when the light emission timing and the processing timing are synchronized in their cycle and phase as shown in the timing chart of FIG. 5 will be described. When the microcomputer 40 receives the image signal from the CCD sensor 22, the image signal for at least one image frame is temporarily stored in the image memory 41 and then transmitted to the image two-dimensional position coordinate calculator 42. At this time, image 2
The two-dimensional position coordinate calculation unit 42 calculates two-dimensional image position coordinates of the light source 12 in each image frame in synchronization with the frame rate of the CCD sensor 22. Similarly, the light emission area calculation unit 44 built in the microcomputer 40
The light emission area of the light source 12 in each image frame is calculated in synchronization with the frame rate of the D sensor 22. Therefore, for example, if the frame rate is 60 Hz and the processing time (dr) is 5/60 seconds, the image two-dimensional position coordinate calculation unit 42 and the light emission area calculation unit 44 determine the image 2 for the light source 12 in five image frames. The dimensional position coordinates and the light emitting area are calculated. Even if there is some noise in the image signal in the image frame, the light source 1 can be subjected to smoothing processing or excluding the noisy image frame.
It is possible to calculate the two-dimensional position coordinates and the light emitting area of the image with respect to 2 with high accuracy.

Further, the information on the calculated two-dimensional position coordinates and the light emission area of the image is transmitted to the PC 50 as position-related data. The distance calculation unit 54 has light emitting area-distance table data in which the relationship between the light emitting area and the distance from the light source 12 to the CCD sensor 22 is associated in advance, and using this data, the distance from the light source to the CCD sensor 22 Is calculated. The real space two-dimensional position coordinate detection unit 52 calculates a real space two-dimensional position coordinate from the real space distance data and the position-related data of the image two-dimensional position coordinate.

Although not shown here, as described above, instead of calculating the real space distance from the light source to the CCD sensor 22 based on the light emitting area, a plurality of light receiving units 2 are used.
By arranging two 0s (receiving stereo light) and simultaneously performing image processing on image signals obtained from two different points, the real space distance can be calculated. Also, to add,
The real space two-dimensional position coordinate detection unit 52 and the distance calculation unit 54 incorporated in the PC 50 are incorporated in the microcomputer 40, and the PC 50 can be omitted.

As described above, the position measuring system 1 of the present invention
According to the method, since no synchronization control means for synchronizing the light emission timing and the image processing timing is provided, the configuration can be extremely simplified, the time required for processing the image is reduced, the power consumption is minimized, and the image signal is reduced. And peripheral circuit devices (for example, the microcomputer 40 and the PC 50) for arithmetically processing the position signal can be greatly simplified.

By the way, in the position measuring system 1 of the present invention, the light emitting unit 10 and the light receiving unit 20 are designed except that the light emitting period (Te) and the light emitting period (Tr) are designed to be the same period. , The light emission cycle (T
Since e) and the light emission period (Tr) are not synchronized, these periods are usually independent of each other. In addition, the light emission phase (the light emission start point at which the light source 12 starts to emit light) and the processing phase (the processing start point at which the image processing unit 30 starts processing an image frame) are also not synchronized, and are independent of each other. I have. Therefore, in the position measuring system 1 of the present invention, a simple and portable suitable suitable for synchronizing the light emission timing (light emission cycle and / or light emission phase) with the image processing timing (processing cycle and / or processing phase). It is preferable to have means and methods.

Hereinafter, a simple means for synchronizing the light emission timing and the image processing timing in the position measurement system 1 of the present invention will be described with reference to FIGS. 3 and 4 again. Note that these means will be described comprehensively below, but it is sufficient for the position measurement system of the present invention to include one of them.

(1) The light emission cycle (Te) and the processing cycle (T
r) is the same. First, a description will be given of a means for synchronizing the light emission phase and the processing phase when the light emitting unit 10 and the microcomputer 40 are configured such that the light emission cycle (Te) and the processing cycle (Tr) are the same. Here, once the light emission phase and the processing phase are once synchronized,
It is assumed that there is no need to adjust the light emission phase and the processing phase again. In a preparation stage before the position measurement system 1 measures the position of the light source 12, the image two-dimensional position coordinate calculation unit 42 analyzes the image signals in all the image frames from the CCD sensor 22 to calculate the light emission phase. When the emission phase and the processing phase are synchronized, for example, an LED
The user is notified of this by using the phase synchronization display unit 33 including a lamp indicator and the like. The user adjusts the light emission phase so as to synchronize the light emission phase with the processing phase by using, for example, the manual light emission phase adjustment unit 16 including the elevation adjustment switch while checking the phase synchronization display unit 33. Thus, the light emission timing and the image processing timing can be reliably synchronized.

Further, the user operates the phase synchronization display section 33.
While confirming, for example, the processing phase may be adjusted so that the processing phase is synchronized with the light emission phase by using the manual processing phase adjustment unit 37 including the elevation adjustment switch.

Further, the processing phase can be automatically synchronized with the light emission phase by using the automatic light receiving phase adjusting section 48 built in the microcomputer 40. Thus,
The light emission timing and the image processing timing are synchronized.

In the above description, once the light emission phase and the processing phase are once synchronized, it is not necessary to adjust the light emission phase and the processing phase again.
Alternatively, the position measurement system 1 may be configured to make another adjustment as necessary.

(2) Light emission cycle (Te) and processing cycle (T
r) is different. Next, a description will be given of a means for synchronizing the light emission cycle with the light emission cycle when the light emission cycle is unknown, such as when the light emitting unit 10 is configured alone. Similarly, once the light emission cycle and the processing cycle are once synchronized, it is not necessary to adjust the light emission cycle and the processing cycle again.
In a preparation stage before the position measurement system 1 measures the position of the light source 12, the image two-dimensional position coordinate calculation unit 42
Analyzes the image signals in all the image frames from the CCD sensor 22 to calculate the light emission cycle. When the light emission cycle and the processing cycle are synchronized, for example, the cycle synchronization display unit 32 including an LED lamp indicator or the like is used. Notify the user to this. The user operates this period synchronization display unit 3
2. While confirming, the light emission cycle is adjusted so that the light emission cycle is synchronized with the processing cycle by using, for example, the manual light emission cycle adjustment unit 14 including the elevation adjustment switch.

The user operates the period synchronization display unit 32
While confirming, for example, the processing cycle may be adjusted so that the processing cycle is synchronized with the light emission cycle by using the manual processing cycle adjusting unit 36 including the elevation adjustment switch.

Further, instead of informing the user that the light emission cycle and the processing cycle are synchronized, the light emission cycle display unit 3
4 or the processing cycle display section 35, the user is shown the light emission cycle value or the processing cycle value, and while confirming this, using the manual light emission cycle adjustment section 14 or the manual processing cycle adjustment section 36, the light emission cycle or processing cycle value is displayed. May be adjusted by the user.

Further, the processing cycle can be synchronized with the light emitting cycle by using the automatic light receiving cycle adjusting section 47 built in the microcomputer 40.

When the light emission cycle and the processing cycle are synchronized, the light emission phase and the processing phase are synchronized by using any means for synchronizing the light emission phase and the processing phase as described in the above (1). . Thus, the light emission timing and the image processing timing can be reliably synchronized.

In the above description, once the light emission cycle and the processing cycle are once synchronized, it is not necessary to adjust the light emission cycle and the processing cycle again.
Alternatively, the position measurement system 1 may be configured to make another adjustment as necessary.

Embodiment 2 Second Embodiment A position measurement system according to a second embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 7, the position measurement system 2 according to the second embodiment of the present invention is similar to the position measurement system according to the first embodiment except that the light emitting unit 10 has three light sources 12a, 12b, and 12c instead of one light source. Since the configuration is the same as that of the position measurement system 1, detailed description will be omitted.

As shown in FIG. 8, similarly, the electric circuit configuration of the position measuring system 2 according to the second embodiment of the present invention is similar to that of FIG.
Except for having points a, 12b, and 12c, the configuration is the same as that of the position measurement system 1 according to the first embodiment, and a detailed description thereof will be omitted.

Referring to the timing chart of FIG. 9, the light emission timing of each light source 12a, 12b, 12c and the processing timing of the microcomputer 40 will be described. As shown in the upper timing chart of FIG. 9, the light source 12a emits pulse light at a light emission timing having a predetermined light emission cycle (Te: one cycle interval) and a predetermined light emission phase (light emission time point), and the light sources 12b and 12c Is the light source 1
2a, and each light source 12a, 12b, 12
Pulse light emission is performed so that the phases of c are at equal intervals. That is, the light sources 12a, 12b, and 12c emit pulses in a predetermined cycle and at a constant time interval.

As shown in the timing chart in the lower part of FIG. 9, the microcomputer 40 has a processing cycle (Tr).
Are defined as three phase block periods at equal intervals, and the image signal is processed in each phase block period. In this way, the light emission phases of the light sources 12a, 12b, and 12c are made to correspond (assign) to each phase block period. At this time, it is preferable that the three phase block periods are equally spaced, and it is convenient to arrange the period (dr) for performing image processing at the center of each phase block period.

Although the microcomputer 40 defines the same number of phase block periods as the light source 12 in the lower timing chart of FIG. 9, the microcomputer 40 divides the processing cycle by a larger natural number (n) to provide more phase block periods. May be defined. For example, a phase block period obtained by dividing a processing cycle into six may be provided for three light sources. In this case, the image processing unit 40 includes the phase block allocating unit 38 so that the user can select which light source is allocated to which block phase period. The user can use, for example, first, second,
It can be set so that image processing is performed during the third and fifth phase block periods and not performed during the third, fourth, and sixth phase block periods. That is, the light emission phase of each of the light sources 12a, 12b, and 12c can be assigned to an arbitrary phase block period. Therefore, the position measurement system of the present invention can perform image processing in response to light from a plurality of light sources having substantially arbitrary phase differences in which the light emission phase differences between the light sources are not equal.

Therefore, the image measurement system 1 according to the first embodiment is different from the image measurement system 2 according to the second embodiment in that one light source 12 is provided in one of the arbitrarily divided phase block periods. It can be seen as a special case assigned.

In any case (regardless of how the processing cycle is divided), the image signals in image frame units formed by the light from the light sources 12a, 12b, and 12c are allocated. Image processing is performed in three phase block periods. Therefore, Embodiment 1
Similarly to the above, the microcomputer 40 can reduce the processing time and can always specify (recognize) the light sources 12a, 12b, and 12c corresponding to the phase block periods.

The light emission timing of the light sources 12a, 12b and 12c and the processing timing of the microcomputer 40 are
By setting as described above, it is possible to synchronize the periods and phases very easily, as in the case where there is only one light source. Next, each of the light sources 12a, 12b, 1
Regarding simple means for synchronizing the light emission timing of 2c and the processing timing of the microcomputer 40,
This will be described with reference to FIGS. It is sufficient for the position measurement system 2 of the present invention to include one of these units described comprehensively below, as in the first embodiment.

FIG. 10 shows a process adjustment display panel 31 including a liquid crystal touch panel 56 and an input numeric keypad 57 as in the first embodiment. The liquid crystal touch panel 56 is
2a, 12b, 12c (LED1, LED2, LED
Regarding 3), there is a cycle synchronization display section 32 that displays “OK” when the light emission cycle and the processing cycle are synchronized, and displays “NG” when they are not synchronized. LCD touch panel 56
Has a phase synchronization display section 33 that displays "OK" when the emission phase and the corresponding processing phase are synchronized, and displays "NG" when they are not synchronized. Further, for example, when the part labeled “emission frequency” is pressed, the liquid crystal touch panel 56 calculates the emission frequency (period) as described above, and displays the emission period of each of the light sources 12a, 12b, and 12c. It has a display unit 34.

The liquid crystal touch panel 56 has a processing cycle display section 35 for displaying the processing frequency (cycle) of the microcomputer 40. This processing cycle display unit 35
When a part on the liquid crystal touch panel 56 where the “processing frequency” and “LED1” intersect is pressed, the display (“60”) is periodically inverted between black and white. This indicates an input enabled state. At this time, if a desired processing frequency (cycle) value is input using the input numeric keypad 57, the processing cycle can be adjusted by the user. That is, the processing cycle display unit 3
Reference numeral 5 also serves as a manual processing cycle adjusting unit 36.

Further, the processing adjustment display panel 31 has a manual processing phase adjuster 37 which can display and adjust the phase difference between the light sources 12a, 12b and 12c in image frame units. When the frame rate is 60 Hz, the light sources 12b and 1
If the phase difference of 2c is 20 and 40 (the unit is the number of image frames), the phase of each light source 12a, 12b, 12c is
They are arranged at equal intervals and can be adjusted by the user as described above. Further, as described above, the processing adjustment display panel 31 includes the light sources 12a, 12b, and 12c.
, A phase block allocating unit 38 capable of allocating a phase block period. For example, the liquid crystal touch panel 56 where “phase block” and “LED2” intersect
Press the upper part to reverse black and white, and in this state LED2
"2" can be selected as the phase block period of (light source 12b).

Finally, the processing adjustment display panel 31 has an image frame adjusting section 39 which allows the user to adjust the number of image frames to be subjected to image processing. As described with reference to FIG. 6, the number of image frames to be subjected to image processing (processing period (d
r)) can be increased or decreased. In FIG.
“4 (the number of image frames)” that is the “image frame” for “LED1” on the process adjustment display panel 31 is periodically inverted to indicate that this parameter is in an adjustable state.

FIG. 11 shows a light emission adjustment display panel (box) 13 including a light emission side liquid crystal touch panel 17 and a lifting / lowering adjustment switch 18. By the same means as the processing adjustment display panel 31, the light sources 12a, 12b, and 12c (LE) are used by using the manual emission cycle adjustment unit 14 and the manual emission phase adjustment unit 15 provided on the emission adjustment display panel (box) 13.
The user can adjust the light emission cycle (frequency) and light emission phase of D1, LED2, LED3). FIG.
Is the “LED” of the light emission adjustment display panel (box) 13.
“0”, which is the “light emission phase” for “1”, is periodically inverted to indicate that this parameter is in an adjustable state.

In FIGS. 10 and 11, the light emission adjustment display panel (box) 13 and the processing adjustment display panel 31 display only the three light sources 12a, 12b, and 12c. Can be displayed for a number of light sources.

Embodiment 3 Third Embodiment A position measuring system according to a third embodiment of the present invention will be described with reference to FIGS.
Will be described. As shown in FIG. 12, the position measuring system 3 according to the third embodiment of the present invention is implemented in the same manner as the position measuring system 3 except that the light emitting unit 10 having one light source is not one but has three light emitting units. Since the configuration is the same as that of the position measurement system 1 according to mode 1, detailed description will be omitted.

Further, as shown in FIG. 13, the electric circuit configuration of the position measuring system 3 according to the third embodiment of the present invention similarly has three light emitting units 10 having one light source instead of one light source. Except for having the light emitting units 10a, 10b, and 10c, the configuration is the same as that of the position measurement system 1 according to the first embodiment, and a detailed description thereof will be omitted.

As described above, the position measuring system 3 has three light emitting units 10 each having one light source 12.
Each of the light emitting units 10a, 10b, and 10c has a predetermined light emitting cycle and a predetermined light emitting phase, similarly to the light emitting unit 10 of the first embodiment, but since the light emitting units 10a, 10b, and 10c are independent of each other. Are not synchronously controlled with each other in their light emission cycle and light emission phase.

Each of the light emitting units 10a, 10b, 10c
As in the first embodiment, the light emission cycle and light emission phase can be adjusted by the user.

On the other hand, the image processing unit 30 of the position measuring system 3 has the same electric circuit configuration as the first and second embodiments, except that it has a light source position comparing and specifying unit 45 described later. However, as described above, each light emitting unit 10a, 10
Since the light emission timings (light emission cycle and light emission phase) of b and 10c are independent of each other, the image processing unit 30 sets the processing timing as one element having a different processing cycle and processing phase (this is referred to as “element processing timing”). ) Is image-processed at the processing timing at which a plurality of images are combined. That is, the image processing unit 30 includes the light emitting units 10a, 10a
The image processing is performed at a processing timing in which a plurality of element processing timings corresponding to the light emission timings b and 10c are superimposed.

Since the image processing unit 30 is configured as described above, the same operation can be performed as described in the first and second embodiments. That is, the image processing unit 30
Informs the user of whether the light emission cycle and the processing cycle, the light emission phase and the processing phase are synchronized for each light source 12, informs the user of the light emission cycle and the processing cycle, and adjusts the processing cycle and the processing phase by the user. , The processing cycle and the processing phase are automatically adjusted, the phase block period is defined, and the user can select which phase block period is to be assigned to each of the light emitting units 10a, 10b, and 10c, and adjusts the number of image frames by the user. It has the means to do it.

However, due to the fact that each of the light emitting units 10a, 10b, and 10c of the third embodiment has a light emitting phase independent of each other, the image processing unit 30 is capable of transmitting light from a plurality of light sources in the same image frame. The light is sometimes subjected to image processing, so that the light source cannot be specified. Therefore, means for dealing with this will be described with reference to FIG.

FIG. 14 is a schematic diagram showing an image frame in which light from a plurality of light sources is image-processed simultaneously. Points P ₁ and P ₂ indicate the two-dimensional position coordinate position of the image of the light source image-processed in the same image frame. The image processing unit 30 controls all the processing cycles and processing phases even when the light from the two light sources is image-processed in the same image frame. , 10c, which two light sources can be specified. The image processing unit 30 includes a light source position comparison specifying unit 45, which
0b, (not shown) latest past (obtained by image processing the previous) image two-dimensional position coordinates in a suitable memory for 10c of the light source stores, possibly as a source point P ₁ For the two light sources, the latest two-dimensional image position coordinates (the image two-dimensional position coordinates of the points Q ₁ and Q ₂ ) are called from this memory, and the distance between the line segments P ₁ Q ₁ and P ₁ Q ₂ is calculated. . Then, the light source position comparison specifying unit 45 determines that Q ₁ or Q ₂ giving the short line segment distance has shifted to P ₁ . In this way, even when light from a plurality of light sources is image-processed in the same image frame, the image processing unit 30 can specify the light source 12.

In the above description, the light receiving section 20 has the CC
Although the description has been made using the D sensor, the position measurement system of the present invention can be configured using a MOS sensor. In this case, the frame rate can be as high as, for example, 1000 Hz.

[0083]

According to the first aspect of the present invention, it is possible to shorten the image processing time and to obtain a simpler position measuring system.

According to the present invention, the image processing time can be reduced while recognizing a plurality of light sources, and a simpler position measurement system can be obtained.

According to the third aspect of the present invention, the image processing time can be reduced while recognizing a plurality of light sources, and a simpler position measuring system can be obtained.

According to the fourth aspect of the present invention, a position measuring system that can easily recognize a plurality of light sources can be provided.

According to the fifth aspect of the present invention, it is possible to provide a position measurement system that allows a user to arbitrarily specify a light source having a light emission phase corresponding to a light reception phase.

According to the sixth aspect of the present invention, it is possible to provide a position measuring system capable of reliably receiving light with high accuracy.

According to the present invention, it is possible to provide a simple position measuring system in which the user can adjust the light emission phase.

According to the present invention, it is possible to provide a simple position measuring system in which the user can adjust the processing phase.

According to the ninth aspect of the present invention, it is possible to provide a simple position measurement system that allows the user to adjust the light emission cycle.

According to the tenth aspect of the present invention, it is possible to provide a simple position measuring system in which the user can adjust the processing cycle.

According to the eleventh aspect of the present invention, a simple position measuring system that automatically adjusts the processing cycle can be provided.

According to the twelfth aspect of the present invention, it is possible to provide a simple position measuring system in which the user can adjust the light emission cycle.

According to the thirteenth aspect of the present invention, it is possible to provide a simple position measuring system in which the user can adjust the processing cycle.

According to the fourteenth aspect of the present invention, it is possible to provide a simple position measuring system in which the user can adjust the light emission phase.

According to the fifteenth aspect of the present invention, it is possible to provide a simple position measuring system in which the user can adjust the processing phase.

According to the sixteenth aspect of the present invention, a position measuring system capable of automatically adjusting the processing phase can be provided.

According to the seventeenth aspect of the present invention, it is possible to provide a simple position measuring system in which the user can adjust the light emission phase.

According to the eighteenth aspect of the present invention, a simple position measuring system that allows a user to adjust the processing phase can be provided.

According to the nineteenth aspect of the present invention, it is possible to provide a simple position measurement system in which the user can adjust the image processing accuracy by adjusting the number of image frames.

According to the twentieth aspect of the present invention, it is possible to provide a position measuring system capable of specifying a light source even when light from a plurality of light sources is image-processed in the same image frame. .

According to the twenty-first aspect of the present invention, it is possible to provide a simpler position measuring method capable of shortening the image processing time.

According to the present invention, image processing time can be reduced while recognizing a plurality of light sources.
It is possible to provide a simpler position measurement method.

According to the twenty-third aspect of the present invention, the image processing time can be reduced while recognizing a plurality of light sources.
It is possible to provide a simpler position measurement method.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing a position measurement system 1 according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a system circuit configuration of the position measurement system 1.

FIG. 3 is a plan view showing a light emission adjustment display panel of the position measurement system 1.

FIG. 4 is a plan view showing a processing adjustment display panel of the position measurement system 1.

FIG. 5 is a timing chart showing light emission timing and processing timing of the position measurement system 1.

FIG. 6 is a partially enlarged view of the timing chart of FIG. 5;

FIG. 7 is a configuration diagram schematically showing a position measurement system 2 according to a second embodiment of the present invention.

FIG. 8 is a block diagram showing a system circuit configuration of the position measurement system 2.

FIG. 9 is a timing chart showing light emission timing and processing timing of the position measurement system 1.

FIG. 10 is a plan view showing a processing adjustment display panel of the position measurement system 2.

FIG. 11 is a plan view showing a light emission adjustment display panel of the position measurement system 2.

FIG. 12 is a configuration diagram schematically showing a position measurement system 3 according to a third embodiment of the present invention.

FIG. 13 is a block diagram showing a system circuit configuration of the position measurement system 3.

FIG. 14 is a schematic diagram illustrating an image frame in which light from a plurality of light sources is image-processed simultaneously.

FIG. 15 is a configuration diagram schematically showing a conventional position recognition device.

FIG. 16 is a block diagram showing a system circuit configuration of a conventional position recognition device.

[Explanation of symbols]

1, 2, 3 position measurement system, 10 light emitting unit, 12
Light source, 13 light emission adjustment display panel, 14 manual light emission cycle adjustment unit, 15 manual light emission phase adjustment unit, 20 light reception unit, 2
2 CCD sensor, 30 image processing section, 31 processing adjustment display panel, 32 cycle synchronization display section, 33 phase synchronization display section, 34 light emission cycle display section, 35 processing cycle display section, 3
6 manual processing cycle adjustment unit, 37 manual processing phase adjustment unit,
38 phase block allocator, 39 image frame adjuster,
40 microcomputer, 41 image memory, 42
Image two-dimensional position coordinate calculator, 44 luminous area calculator,
45 light source position comparison / identification unit, 47 automatic processing cycle adjustment unit, 48 automatic processing phase adjustment unit, 50 PC (personal computer), 52 real space two-dimensional position coordinate detection unit, 54 distance calculation unit.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA03 AA04 AA06 AA19 BB05 BB29 CC16 DD02 DD06 FF23 GG07 GG08 GG09 GG12 GG13 GG21 JJ01 JJ26 LL04 NN02 NN05 NN11 QQ00 QQ01 QQ21 QQ23 QQ24 Q28

Claims (23)

[Claims] 1. A light-emitting unit including one light source that emits light at a light-emission timing having a predetermined light-emission cycle and a predetermined light-emission phase; and receiving light from the light source to form an image signal for at least one image frame. A light receiving unit, and an image processing unit that processes the image signal at a processing timing having a predetermined processing cycle and a predetermined processing phase to form position information on the position of the light source. Measurement system. 2. A light-emitting unit including a plurality of (k) light sources that emit light at predetermined light-emission periods and light-emission timings having different light-emission phases; A light receiving unit that forms an image signal for at least one image frame; and an image that processes the image signal at a processing timing having a predetermined processing cycle and a plurality of processing phases to form position information regarding the position of each light source. And a processing unit. 3. A plurality of (k) light-emitting portions including one light source that emits light at a light-emission timing having a predetermined light-emission cycle and a predetermined light-emission phase; A light receiving unit that forms an image signal for at least one image frame; and a light receiving unit that processes the image signal at a processing timing obtained by superposing a plurality of element processing timings having a predetermined processing cycle and a predetermined processing phase. An image processing unit for forming position information on each of the positions. 4. The image processing section sets a plurality of processing cycles (n; k).
4. The position measurement system according to claim 1, wherein the phase is divided into ≤n) phase blocks, and each light receiving phase is included in one phase block period. 5. The position measurement system according to claim 1, wherein the image processing unit has a phase block allocating unit that allocates each light receiving phase to an arbitrary phase block period. 6. The position measuring system according to claim 1, wherein each light receiving phase is located at the center of one phase block period. 7. The light emitting unit according to claim 7, wherein the light emitting cycle and the processing cycle are the same, and the light emitting unit has a light emitting phase adjusting unit that can adjust each light emitting phase so that each light emitting phase is synchronized with the processing phase. Item 3. The position measurement system according to items 1 to 3. 8. The light-emitting device according to claim 8, wherein the light-emission cycle and the processing cycle are the same, and the image processing section has a light-receiving phase adjustment section that can adjust the processing phase so that the processing phase is synchronized with each light-emission phase. Item 3. The position measurement system according to items 1 to 3. 9. The image processing section has a cycle synchronization display section for informing a user whether or not the light emitting cycle and the processing cycle are synchronized. The light emitting section has a light emitting cycle such that the light emitting cycle is synchronized with the processing cycle. The position measuring system according to claim 1, further comprising a light emission cycle adjusting unit that can adjust the position. 10. The image processing unit has a period synchronization display unit that informs a user whether or not the light emission cycle and the processing period are synchronized. The image processing unit is configured to synchronize the processing period with the light emission period.
4. The position measuring system according to claim 1, further comprising a light receiving cycle adjusting unit capable of adjusting a processing cycle. 11. The position measurement system according to claim 1, wherein the image processing unit has an automatic light receiving cycle adjusting unit that automatically adjusts the processing cycle so that the light emitting cycle and the processing cycle are synchronized. . 12. The light emitting unit according to claim 1, wherein the light emitting unit includes a light emitting cycle display unit for notifying a user of a light emitting cycle value, and the light emitting unit includes a light emitting cycle adjusting unit capable of adjusting a light emitting cycle. Position measurement system. 13. The image processing unit according to claim 1, wherein the image processing unit includes a processing cycle display unit that notifies a user of the processing cycle value, and the image processing unit includes a processing cycle adjustment unit that can adjust the processing cycle. 3 position measurement system. 14. The image processing section has a phase synchronization display section for informing a user whether or not each light emission phase and the processing phase are synchronized. The light emitting section is configured to synchronize each light emission phase with the processing phase. 4. The position measurement system according to claim 1, further comprising a light emission phase adjustment unit that can adjust each light emission phase. 15. The image processing section has a phase synchronization display section for notifying a user whether or not each light emission phase and the processing phase are synchronized. The image processing section is configured to synchronize the processing phase with each light emission phase. 4. The position measuring system according to claim 1, further comprising a light receiving phase adjusting unit that can adjust a processing phase by a user. 16. The position measuring system according to claim 1, wherein the image processing unit has an automatic light receiving phase adjusting unit that automatically adjusts the processing phase so that the emission phase and the processing phase are synchronized. . 17. The light emitting unit according to claim 1, wherein the light emitting unit has a light emitting phase display unit for notifying a user of a light emitting phase value, and the light emitting unit has a light emitting phase adjusting unit capable of adjusting a light emitting phase. Position measurement system. 18. The image processing unit according to claim 1, wherein the image processing unit includes a processing phase display unit that notifies a user of a processing phase value, and the image processing unit includes a processing phase adjustment unit that can adjust a processing phase. 3 position measurement system. 19. The position measurement system according to claim 1, wherein the image processing unit has an image frame adjustment unit that can adjust the number of image frames corresponding to an image signal to be processed. 20. The image processing section, further comprising: a light source position comparing and specifying section capable of specifying a light source corresponding to each position information when light from a plurality of light sources is received in one image frame. 3 position measurement system. 21. A step of causing one light source to emit light at a light emission timing having a predetermined light emission cycle and a predetermined light emission phase; and receiving light from the light source to form an image signal for at least one image frame. And a step of processing the image signal at a processing timing having a predetermined processing cycle and a predetermined processing phase to form position information on the position of the light source. 22. A step of causing a plurality of (k) light sources to emit light at a light emission timing having a predetermined light emission cycle and a different light emission phase; receiving light from the light sources, and at least one Forming an image signal for one image frame; and processing the image signal at a processing timing having a predetermined processing cycle and a plurality of processing phases to form position information on the position of each light source. A position measuring method, comprising: 23. A step of simultaneously performing a sub-step of causing one light source to emit light at a light emission timing having a predetermined light emission cycle and a predetermined light emission phase for a plurality of light sources having different light emission cycles and light emission phases. Receiving light from a light source and forming, for each light source, an image signal for at least one image frame; and determining an element processing timing having a predetermined processing cycle and a predetermined processing phase for the image signal. Forming position information on the position of each light source by processing at a plurality of overlapping processing timings.