JPH10170650A - Distance measuring method using ultrasonic wave reflecting plate in photographing image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure an accurate distance of an object by arranging an ultrasonic wave reflecting plate to make an ultrasonic wave locus and the photographing optical axis of a video camera coincide with each other. SOLUTION: Since the optical axis 67 and an ultrasonic wave locus 68 coincide with each other between an object 65 and an ultrasonic wave reflecting point 69, when both distances between an ultrasonic wave sensor 66 and the ultrasonic wave reflecting point 69 and between a fixing hole 63 of a video camera or the like and the ultrasonic wave reflecting point 69 are equal to each other, an object 1 of a drawing 1 and a video camera 2, and the object 1 and an ultrasonic wave sensor 3 are at an equal distance. Therefore, in a method using an ultrasonic wave reflecting plate, a measuring distance between the object l and the ultrasonic wave sensor 3 becomes equal to a distance between the object l and the video camera 2, and when the object 1 is small, and when a recess-projection exists in a photographing position 9 of the object 1, and when the object 1 makes a movement such as the approach, and even when the photographing position 9 is expanded by connecting a zoom lens to the video camera 2, an always accurate distance can be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a video camera 2
In an apparatus for measuring the distance to the subject 1 necessary for taking an image by an image input device using an ultrasonic wave, when the subject 1 in FIG. Video generated when the imaging position 7 is shifted from the ultrasonic reflection position 6 when, for example, the camera 1 moves toward the video camera 2 or when a zoom lens is connected to the video camera 2 to enlarge an imaging portion. Eliminate the error in the distance between the camera 2 and the subject 1 and
The present invention relates to a distance measuring method including an ultrasonic reflector 62 necessary for measuring an accurate distance between the camera and the video camera 2.

[0002]

2. Description of the Related Art An apparatus configuration of a distance measuring system in image photographing according to the prior art will be described with reference to FIG. FIG. 2 shows an actual device configuration using a distance measuring method in conventional image capturing, wherein 1 is a subject, 2 is an image input device for capturing a subject 1 with a video camera, and 3 is an ultrasonic sensor with an ultrasonic sensor. Is a device for emitting ultrasonic waves and emitting ultrasonic waves again, 4 is a device for calculating the distance from the ultrasonic transit time t calculated by causing the ultrasonic sensor 3 to generate ultrasonic waves with the ultrasonic distance meter, and using Formula 1; 5 is a control device and a video camera 2
6 is an apparatus for controlling the operation of an ultrasonic sensor, and 6 is an ultrasonic reflection position at which the ultrasonic wave radiated from the ultrasonic sensor 3 is reflected by the subject 1.
Is a photographing position of the subject 1 photographed by the video camera 2. The calculation formula 1 is based on the ultrasonic traveling time t and the current temperature T until the ultrasonic wave radiated from the ultrasonic sensor 3 is reflected by the subject 1 and input to the ultrasonic sensor 3 again.
This is a calculation formula for calculating the distance L from the subject 1 to the video camera 2 by (Celsius).

The ultrasonic distance meter 4 shown in FIG.
Then, the ultrasonic wave is radiated to the subject 1, and the radiated ultrasonic wave reflects on the subject 1 and is again input to the ultrasonic sensor 3, and at the same time, outputs an information signal to the ultrasonic distance meter 4. next,
The ultrasonic range finder 4 transmits the ultrasonic wave to the ultrasonic sensor 3 until the information signal is input from the ultrasonic sensor 3 to the ultrasonic traveling time between the ultrasonic sensor 3 and the subject 1. t is calculated, and the distance L from the subject 1 to the ultrasonic sensor 3 is calculated by Expression 1 using the current temperature as T. In this case, the distance between the subject 1 and the video camera 2 and the distance between the subject 1 and the ultrasonic sensor 3 are the same, and the distance L calculated from the formula 1 by the ultrasonic distance meter 4 is the distance between the subject 1 and the video camera 2.
Is the distance between The distance L calculated by the ultrasonic range finder 4 is input to the control device 5 to perform operation control such as focus control for adjusting the video camera 2 to focus a captured image. The method by which the control device 5 controls the video camera 2 varies depending on the type of the video camera 2, but most of the methods include a distance between the subject 1 and the video camera 2 and data set in advance for controlling the video camera 2. The control device 5 controls the operation by outputting a digital signal to the video camera 2 as the control setting data as an analog signal or data such as a voltage or a current.

[0004]

In the distance measurement method in image capturing, when the subject 1 in FIG. 2 is small, when the subject 1 has irregularities in the photographing position 7, the subject 1 moves toward the video camera 2 or the like. Error occurs in the distance between the video camera 2 and the subject 1 caused by a shift between the imaging position 7 and the ultrasonic wave reflection position 6 when the zoom lens is connected to the video camera 2 and the imaging portion is enlarged. It is impossible to accurately measure the distance between the subject 1 and the video camera 2 by the conventional distance measuring method in image capturing.

A case in which a distance measuring method in image photographing according to the prior art is implemented will be described with reference to FIGS. FIG.
2A shows a case where the subject 1 in FIG. 2 is large and has no unevenness, 11 is an ultrasonic sensor, 12 is a video camera, 13 is a subject, 1
Reference numeral 4 denotes a photographing position of the subject 13 photographed by the video camera 12, and reference numeral 15 denotes an ultrasonic wave reflection position at which the ultrasonic wave emitted by the ultrasonic sensor 11 is reflected by the subject 13. FIG. 3A is FIG.
In the case where the subject 1 is small and has no irregularities, and the ultrasonic radiation direction of the ultrasonic sensor 3 in FIG. 2 is parallel to the optical axis 9 of the video camera 2, 21 is an ultrasonic sensor, 22 is a video camera, and 23 is The subject 24 is a photographing position of the subject 23 photographed by the video camera 22. FIG. 3C shows a case where the subject 1 shown in FIG. 2 is small and has no irregularities, and the ultrasonic radiation direction of the ultrasonic sensor 3 is not parallel to the optical axis 9 of the video camera 2 in FIG. , 32 denotes a video camera, 33 denotes a subject, 34 denotes a photographing position of a subject 33 photographed by the video camera 32, and 35 denotes an ultrasonic sensor 31.
Is an ultrasonic reflection position at which the ultrasonic wave radiated is reflected by the subject 33. In this case, the imaging position 34 and the ultrasonic reflection position 35 are the same. FIG. 3D shows a case where the subject 1 in FIG. 2 is large and has irregularities, and the ultrasonic radiation direction of the ultrasonic sensor 3 in FIG. 2 is parallel to the optical axis 9 of the video camera 2. Reference numeral 41 denotes the ultrasonic sensor. , 42 is a video camera, 43 is a subject, 4
Reference numeral 4 denotes a photographing position of the subject 43 photographed by the video camera 42, and reference numeral 45 denotes an ultrasonic wave reflection position at which the ultrasonic wave emitted by the ultrasonic sensor 41 is reflected by the subject 43. FIG. 3E is FIG.
In the case where the subject 1 is large and has irregularities, and the ultrasonic radiation direction of the ultrasonic sensor 3 in FIG. 2 is not parallel to the optical axis 9 of the video camera 2, 51 is an ultrasonic sensor, 52 is a video camera, 53 is a subject, 56 is a subject position to which the subject 53 has moved, 54 is a photographing position of the subject 53 photographed by the video camera 52, and 55 is an ultrasonic reflection position at which ultrasonic waves emitted by the ultrasonic sensor 51 are reflected by the subject 53. In this case, the imaging position 54 and the ultrasonic reflection position 55 are the same.

In the case of FIG. 3A, the distance to the ultrasonic reflection position 15 where the ultrasonic wave radiated from the ultrasonic sensor 11 is reflected by the subject 13 is the same as the distance between the video camera 12 and the subject 13. The measurement of the distance from the video camera 12 to the subject 13 can be performed by a conventional distance measurement method in image capturing. In the case of FIG. 3A, since the ultrasonic wave radiated from the ultrasonic sensor 21 cannot be reflected by the subject 23, the distance from the video camera 22 to the subject 23 cannot be measured by the distance measuring method in the conventional image capturing. It is. FIG. 3C shows a case where the imaging position 34 and the ultrasonic reflection position 35 are made the same by making an angle in the radiation direction of the ultrasonic wave radiated from the ultrasonic sensor 21 in FIG. There is an error between the distance of the ultrasonic sensor 31 and the distance between the ultrasonic sensor 31 and the subject 33, and the reflection direction of the ultrasonic wave reflected at the ultrasonic reflection position 35 is reflected in a different direction from the ultrasonic sensor 31 in consideration of the angle of incidence on the subject 33. Object 33 from the video camera 32
It is theoretically impossible to measure the distance to the distance by the distance measurement method in the conventional image capturing. However, the ultrasonic wave reflected at the ultrasonic reflection position 35 is actually the ultrasonic reflection position 3
The distance from the video camera 32 to the subject 33 is measured by a conventional distance measuring method in image capturing, because part of the ultrasonic wave may be reflected in the direction of the ultrasonic sensor 31 due to irregular reflection due to the state of the surface of 5. Although not absolutely impossible, accurate and stable distance measurement cannot be expected. In the case of FIG. 3D, the distance between the video camera 42 and the subject 43 and the distance between the ultrasonic sensor 41 and the subject 43 cause a large error in measurement. This is not possible with a distance measurement method in image capturing according to the prior art. 3 is FIG.
The imaging position 54 and the ultrasonic reflection position 55 are set at an angle in the radiation direction of the ultrasonic waves radiated from the ultrasonic sensor 41 of FIG.
When the distance is the same, an error occurs between the distance between the video camera 52 and the subject 53 and the distance between the ultrasonic sensor 51 and the subject 53, and the reflection direction of the ultrasonic wave reflected at the ultrasonic wave reflection position 55 indicates the incident angle of the subject 53. Considering the ultrasonic sensor 51
It is theoretically impossible to measure the distance from the video camera 52 to the subject 53 because the light is reflected in a direction different from that of the conventional technique. However,
Actually, the ultrasonic wave reflected at the ultrasonic reflection position 55 is irregularly reflected depending on the state of the surface of the ultrasonic reflection position 55, and a part of the ultrasonic wave may be reflected in the direction of the ultrasonic sensor 51. Although the measurement of the distance up to the distance is not absolutely impossible with the conventional distance measurement method for image capturing, accurate and stable distance measurement cannot be expected. When the subject 53 has moved to the moved subject position 56, the distance between the video camera 52 and the subject 53 and the distance between the ultrasonic sensor 51 and the subject 53 have a large measurement error, as in FIG. Accurate measurement of the distance from the video camera 52 to the subject 53 is impossible with the conventional distance measurement method for image capturing.

The present invention relates to an apparatus for measuring the distance to an object 1 necessary for photographing an image with an image input device such as a video camera 2 by ultrasonic waves. When the object 1 shown in FIG. When the photographing position 7 has irregularities, when the subject 1 moves such as approaching the video camera 2, or when the photographing portion is enlarged by connecting a zoom lens to the video camera 2, the photographing position 7 and the ultrasonic reflection position are used. The distance measurement between the subject 1 and the video camera 2 is measured by the conventional distance measurement method for image capturing because of an error in the distance between the video camera 2 and the subject 1 caused by the shift of 6. Aims to solve the disadvantages that are not possible.

[0008]

In order to achieve this object, the present invention relates to a method in which an ultrasonic wave radiated from the ultrasonic sensor 3 shown in FIG. Ultrasonic trajectory 7 as a trajectory and video camera 2
Is a distance measuring method using an ultrasonic reflecting plate in image photographing provided with an ultrasonic reflecting means 6 using an ultrasonic reflecting plate 62 for making the optical axis 8 for photographing the subject 1 the same.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the arrangement of a distance measuring system using an ultrasonic reflector in image capturing according to the present invention.
This will be described with reference to FIG. FIG. 1 shows an example of an apparatus configuration of a distance measuring system using an ultrasonic reflector in image capturing according to the present invention, wherein 1 is a subject, 2 is a video camera, 3
Is an ultrasonic sensor, 4 is an ultrasonic distance meter, 5 is a control device,
6 is an ultrasonic reflecting means, 7 is an ultrasonic trajectory which is a trajectory of the ultrasonic wave radiated by the ultrasonic sensor 3, and 8 is an optical axis where the video camera 2 photographs the subject 1. In the case of the present invention, the ultrasonic trajectory 7 and the optical axis 8 are the same. FIG. 4 is a side sectional view of the ultrasonic reflecting means 6 shown in FIG.
Is a housing of an ultrasonic reflecting device, 62 is an ultrasonic reflecting plate, 63 is a fixing hole of a video camera or the like, 64 is a photographing hole, 65 is a subject, 66 is an ultrasonic sensor, and 67 is a fixing hole 63 of a video camera or the like. The optical axis 68 when the video camera is fixed, the ultrasonic wave output from the ultrasonic sensor 66 and the object 65
The locus 69 of the reflected ultrasonic wave is a reflection point of the ultrasonic reflector 62 of the ultrasonic wave radiated from the ultrasonic sensor 66.

The ultrasonic distance meter 4 shown in FIG.
Then, the ultrasonic wave emitted from the ultrasonic wave reflecting means 6 passes through the ultrasonic wave trajectory 7 and the optical axis 8 so that the ultrasonic wave is emitted to the subject 1. The emitted ultrasonic wave is the subject 1
Is reflected, passes through the ultrasonic reflecting means 6, and is again input to the ultrasonic sensor 3, and at the same time, the information signal is transmitted to the ultrasonic range finder 4.
Output to Next, the ultrasonic distance meter 4 is an ultrasonic sensor 3
The ultrasonic sensor 3 and the subject 1 are determined based on the time from the start of emitting ultrasonic waves to the input of an information signal from the ultrasonic sensor 3.
Then, the ultrasonic traveling time t between the subject and the ultrasonic sensor 3 is calculated, and the distance L from the subject 1 to the ultrasonic sensor 3 is calculated by Expression 1 using the current temperature as T. In this case, the distance between the subject 1 and the video camera 2 and the distance between the subject 1 and the ultrasonic sensor 3 are the same, and the distance L calculated from the formula 1 by the ultrasonic distance meter 4 is the distance between the subject 1 and the video camera 2. Is the distance between The distance L calculated by the ultrasonic distance meter 4 is input to the control device 5,
The control device 5 performs operation control such as focus control for adjusting a focus of an image captured by the video camera 2.

The ultrasonic reflecting means 6 shown in FIG. 1 will be described with reference to FIG. The housing 61 of the ultrasonic reflection device is a box having a fixing hole 63 and an imaging hole 64 for an image input device such as a video camera and a mechanism for fixing the ultrasonic reflection plate 62 and the ultrasonic sensor 66. The ultrasonic waves emitted from the ultrasonic sensor 66 are incident on the ultrasonic reflector 62 at an incident angle of 45 °, are reflected at a reflection angle of 45 °, and are emitted from the imaging hole 64 to the subject 65. The ultrasonic waves radiated to the subject 65 are reflected,
4, the light enters the housing 61 of the ultrasonic reflection device, enters the ultrasonic reflection plate 62 at an incident angle of 45 °, is reflected at a reflection angle of 45 °, and is input to the ultrasonic sensor 66 again. Subject 6
The photographing of 5 is performed by fixing holes 63 of an image input device such as a video camera.
The optical axis 67 to be photographed is positioned on the surface of the ultrasonic reflecting plate 62 with the ultrasonic wave radiated from the ultrasonic sensor 66 and the ultrasonic trajectory 68 reflected from the subject 65. Ultrasonic reflection point 69
To the subject 65 are the same.

Since the optical axis 67 and the ultrasonic trajectory 68 are the same between the subject 65 and the ultrasonic reflection point 69, the ultrasonic sensor 66 and the ultrasonic reflection point 69 shown in FIG. When an image input device such as a video camera is connected to the position of the fixing hole 63) and the ultrasonic reflection point 69
In FIG. 1, the subject 1 and the video camera 2 and the subject 1 and the ultrasonic sensor 3 are equidistant in FIG. Thus, the distance between the subject 1 and the ultrasonic sensor 3 shown in FIG.
When the subject 1 is small, the subject 1
Even when the shooting position 9 has irregularities, when the subject 1 moves such as approaching, or when the shooting position 9 is enlarged by connecting a zoom lens to the video camera 2, accurate distance measurement can always be performed. Is evident.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of a case where a distance measuring system using an ultrasonic reflector in image photographing according to the present invention is realized.
This will be described with reference to FIG. FIG. 5 is a structural view in the case where the ultrasonic reflecting means 6 of FIG. 1 is implemented as a device, in which a is a side sectional view, a is a developed view, 71 is a horizontal width, 72 is a vertical width, 73
Is a depth, 74 is a center position of a part of the ultrasonic sensor 76 that emits ultrasonic waves, 75 is a center position of a fixing hole for connecting an image input device such as a video camera, 76 is an ultrasonic sensor,
77 is an ultrasonic reflector that reflects ultrasonic waves, 78 is the distance from the center position 75 of the fixing hole of a video camera or the like to the ultrasonic reflector 77, and 79 is the ultrasonic reflector from the center position 74 of the part that emits ultrasonic waves. Distance to 77, 80 is the ultrasonic reflector 7
Reference numeral 7 denotes a mounting angle in the apparatus, 81 denotes a mounting position of the ultrasonic reflecting plate 77, and 82 denotes a photographing hole.

The structure shown in FIG.
Is 45 ° and the horizontal width 71 and the vertical width 72 are the same length, but the depth 73 is the center position 75 of the fixing hole of the video camera or the like.
It is indefinite because it depends on the size of an image input device such as a video camera connected to the camera, and is a vertical extension of the center position 74 of the ultrasonic wave emitting portion and a vertical extension of the fixing hole center position 75 of the video camera or the like. Are arranged so as to intersect at right angles on the upper surface of the ultrasonic reflecting plate 77. Further, since the ultrasonic reflecting plate 77 needs to reflect the ultrasonic waves efficiently and photograph the subject 1 with the video camera 2, it is preferable that the ultrasonic reflecting plate 77 has a good transparency and a transparent plate with little refraction of light.

When the ultrasonic reflecting means 6 shown in FIG. 1 is connected to the ultrasonic reflecting means 6 shown in FIG. 1, the distance between the subject 1 and the ultrasonic sensor 3 is set to be equal to that of the subject 1. Since the distance between the subject 1 and the video camera 2 is equal to the distance between the subject 1 and the video camera 2, it is possible to accurately measure the distance between the subject 1 and the video camera 2.

[0016]

According to the present invention, in an apparatus for measuring the distance to an object 1 necessary for photographing an image with an image input device such as a video camera 2 by ultrasonic waves, the object 1 shown in FIG. When the photographing position 7 of the subject 1 has irregularities, when the subject 1 moves such as approaching to the video camera 2 or when the photographing portion is enlarged by connecting a zoom lens to the video camera 2, the photographing position 7 is determined. This method can eliminate an error in the distance between the video camera 2 and the subject 1 caused by the shift of the ultrasonic wave reflection position 6, and can measure the accurate distance between the subject 1 and the video camera 2.

[Brief description of the drawings]

FIG. 1 is a block diagram of a distance measurement method using an ultrasonic reflector in image capturing according to the present invention.

FIG. 2 is a block diagram of a distance measuring method in image capturing according to the related art.

FIG. 3 is an explanatory diagram of a case where a device of a distance measuring method in image capturing according to a conventional technique is implemented.

FIG. 4 is a cross-sectional view from the side when the ultrasonic reflecting means 6 of FIG. 1 is implemented as a device.

FIG. 5 is a structural diagram when the ultrasonic reflecting means 6 of FIG. 1 is implemented as a device.

[Formula 1] 4 is a calculation formula for calculating the distance between the subject 1 and the video camera 2 by the ultrasonic distance meter 4 according to the present invention and the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Subject 2 Video camera 3 Ultrasonic sensor 4 Ultrasonic range finder 5 Control device 6 Ultrasonic reflecting means 7 Ultrasonic trajectory 8 Optical axis 9 Shooting position

Claims (1)

[Claims] The present invention relates to an apparatus for measuring a distance to a subject 1 required for photographing an image with an image input device such as a video camera 2 by ultrasonic waves. This is a distance measurement method using an ultrasonic reflector in image capturing, which includes an ultrasonic reflector 62 between the apparatus and the apparatus.