JP2001045520A - Three-dimensional image detector and optical communication receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a three-dimensional image detector, which emits a range finding light to an object to detect a distance up to the object, to employ one light source so as to conduct range fining and transmission of data through an optical communication. SOLUTION: A light emitting device 14 emits a pulse-modulated range finding light to an object. A camera body 10 receives a reflected light via an image pickup lens 11 to detect a distance up to the object and stores detected distance data to a memory at once. The light emitting device 14 emits a communication light with a pulse frequency modulation region different from that of the range finding light to transmit the distance data or the like stored in the memory to a device provided to an outside of the camera body 10. A light receiving device 47 receives the communication light and outputs the detected light to a computer 46 as received data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a three-dimensional image detecting apparatus for detecting a three-dimensional shape of a subject using a light propagation time measuring method.

[0002]

2. Description of the Related Art A subject is imaged by a three-dimensional image detecting device,
In order to obtain a three-dimensional image of a subject from the detected distance data and image data, it is necessary to provide high image processing capability and sufficient storage capacity. However, if circuits and equipment necessary for this are provided, the size of the device becomes large, so that it is difficult to obtain a three-dimensional image with a small and lightweight three-dimensional image detecting device. Therefore, the conventional three-dimensional image detecting apparatus is connected to a computer using an interface cable, and detected data is sequentially sent to the computer via the cable and processed on the computer.

[0003]

In order to form a three-dimensional image of a subject from detected distance data and image data,
The subject must be imaged from multiple directions and synthesized. However, if the three-dimensional image detection device and the computer are connected by a cable, the movable range of the three-dimensional image detection device is limited, and it is difficult to perform imaging from multiple directions. It also hinders operator movement and equipment operation.

[0004] The present invention provides a small and lightweight operable device capable of transferring data to a computer without using a cable.
It is intended to obtain a three-dimensional image detection device.

[0005]

According to the present invention, there is provided a three-dimensional image detecting apparatus comprising: a light source for irradiating light; an image pickup device capable of accumulating electric charges corresponding to an amount of received light; Irradiating light, a distance information detecting means for detecting distance information to the subject by receiving reflected light from the subject with an image sensor, and irradiating communication light using a space as a transmission path by controlling light emission of a light source, Information transmission means for transmitting data to an external device.

[0006] Preferably, the pulse frequency modulation ranges of the distance measuring light and the communication light are different. As a result, the distance measuring light and the communication light are not confused at the time of reception. The transmitted data relates to, for example, distance information. Further, the three-dimensional image detecting device preferably includes image information detecting means for forming an image of the subject with an image sensor and detecting image information of the subject. The data transmitted at this time relates to, for example, image information.

[0007] The three-dimensional image detecting device can preferably select whether or not to drive the information transmitting means.

Further, the optical communication receiving apparatus according to the present invention is characterized in that the receiving control for receiving data transmitted by the communication light is started by receiving the distance measuring light.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a camera-type three-dimensional image detection device according to an embodiment of the present invention.

On the front of the camera body 10, a finder window 12 is provided at the upper left of the taking lens 11, and a flash 13 is provided at the upper right. On the upper surface of the camera body 10, right above the taking lens 11, a distance measuring light emitting device (light source) 14 for irradiating laser light, which is distance measuring light, is provided. A release switch 15, an information transmission mode setting button 24, and a liquid crystal display panel 16 are provided on the left side of the distance measuring light emitting device 14, and a mode switching dial 1 is provided on the right side.
7 and a V / D mode changeover switch 18 are provided.
On the side of the camera body 10, a card insertion slot 19 for inserting a recording medium such as an IC memory card is formed, and a video output terminal 20 is provided.

FIG. 2 is a block diagram showing a circuit configuration of the camera shown in FIG. An aperture 25 is provided in the taking lens 11. The opening of the aperture 25 is determined by the iris drive circuit 2.
Adjusted by 6. The focus adjustment operation and the zooming operation of the taking lens 11 are controlled by a lens drive circuit 27.

On the optical axis of the taking lens 11, an image pickup device (C
CD) 28 is provided. A subject image is formed on the CCD 28 by the photographing lens 11, and charges corresponding to the subject image are generated. Operations such as a charge accumulation operation and a charge read operation in the CCD 28 are controlled by the CCD drive circuit 30. The charge signal, that is, the image signal, read from the CCD 28 is amplified by the amplifier 31 and the A / A
The analog signal is converted into a digital signal in the D converter 32. The digital image signal is output from the imaging signal processing circuit 3
In the image memory 3, processing such as gamma correction is performed.
4 is temporarily stored. The iris drive circuit 26, lens drive circuit 27, CCD drive circuit 30, and image signal processing circuit 33 are controlled by a system control circuit 35.

The image signal is read from the image memory 34 and supplied to the LCD drive circuit 36. The LCD drive circuit 36 operates in accordance with the image signal, and thereby the image display L
An image corresponding to the image signal is displayed on the CD panel 37.

If the camera is connected to a monitor device provided outside the camera body 10 by a cable, the image memory 34
Are read from the TV signal encoder 38,
It can be transmitted to the monitor device via the video output terminal 20. The system control circuit 35 is connected to the interface circuit 40, and the interface circuit 40 is connected to the interface connector 21. Therefore, if the camera is connected to a computer provided outside the camera body 10, the image signal read from the image memory 34 is transmitted to the interface connector 21.
Can be transmitted to a computer connected to the computer. The system control circuit 35 includes a recording medium control circuit 42.
Is connected to the image recording device 43 via the. Therefore, the image signal read from the image memory 34 can be recorded on a recording medium M such as an IC memory card mounted on the image recording device 43.

A light emitting element control circuit 44 is connected to the system control circuit 35. The light emitting device 14 is provided with a light emitting element 14a and an illumination lens 14b, and the light emitting operation of the light emitting element 14a is controlled by a system control circuit 35 and a light emitting element control circuit 44. Light emitting element 1
Reference numeral 4a irradiates a laser beam which is a distance measuring light or a communication light.
The light is radiated to the entire subject via b, and at the time of communication, is radiated to an area including a communication light receiver connected to a computer. The light reflected from the subject is the taking lens 1
Incident on 1. By detecting this light by the CCD 28, a three-dimensional image of the subject is measured as described later. The detected data is transmitted to the computer by the light emitting operation of the light emitting element 14a. In this measurement, the control of the transfer operation timing and the like in the CCD 28 is performed by the system control circuit 35 and the CCD drive circuit 30.
Done by

The system control circuit 35 includes a release switch 15, a mode switching dial 17, a V / D mode switching switch 18, an information transmission mode setting button 24.
Switch group 45 composed of a liquid crystal display panel (display element)
16 are connected.

FIG. 3 shows a state in which a distance information detecting operation for detecting data relating to a distance to each point on the surface of the subject and an information transmitting operation for transmitting distance data, image data, and the like from the camera to an external device are performed. This is a schematic representation.

The distance information is detected by irradiating the light emitting device 14 toward the subject S and reflecting the reflected light through the imaging lens 11 to the CCD.
This is performed by receiving light at 28. On the other hand, data transmission to the computer 46 is performed by irradiating communication light from the light emitting device 14 and receiving and detecting the communication light with the light receiver 47 in the irradiation area U. The communication light detected by the light receiver 47 is converted into an electric signal, sent to the computer 46 as received data, subjected to predetermined image processing, and displayed on a display or the like. Note that pulse-modulated laser light is used as the distance measuring light and the communication light emitted from the light emitting device 14, and the modulation frequency range of the communication light is, for example, one of that of the distance measuring light.
It is 0 times. Therefore, the distance measuring light and the communication light have different modulation frequency ranges and are not confused when receiving the light receiver 47.

Next, the principle of distance measurement in the present embodiment will be described with reference to FIGS. FIG.
, The horizontal axis is time t.

The distance measuring light output from the distance measuring device B is reflected by the subject S and received by a CCD (not shown). The distance measuring light is a pulsed light having a predetermined pulse width H, and therefore, the reflected light from the subject S is also a pulsed light having the same pulse width H. The rise of the reflected light pulse is delayed by a time δ · t (δ is a delay coefficient) from the rise of the distance measuring light pulse. Since the ranging light and the reflected light have traveled twice the distance r between the distance measuring device B and the subject S, the distance r is given by r = δ · t · C / 2 (1) can get. Where C is the speed of light.

For example, a state in which the reflected light can be detected from the rise of the pulse of the distance measuring light is determined, and the state is switched to an undetectable state before the reflected light pulse falls, that is, a reflected light detection period T is provided. And the received light amount A during the reflected light detection period T is a function of the distance r. That is, the light receiving amount A decreases as the distance r increases (the time δ · t increases).

In the present embodiment, utilizing the above-described principle,
In each of a plurality of photodiodes (imaging elements) provided on the CCD 28 and two-dimensionally arranged, the received light amount A
, The distance from the camera body 10 to each point on the surface of the subject S is detected, and data of a three-dimensional image relating to the surface shape of the subject S is input collectively.

FIG. 6 is a diagram showing the arrangement of the photodiode 51 and the vertical transfer unit 52 provided on the CCD 28.
FIG. 7 is a cross-sectional view of the CCD 28 cut along a plane perpendicular to the substrate 53. This CCD 28 is a conventionally known interline type CCD, and uses a VOD for sweeping out unnecessary charges.
(Vertical overflow drain) method.

The photodiode 51 and the vertical transfer section 52 are formed along the surface of the n-type substrate 53. The photodiodes 51 are two-dimensionally arranged in a lattice, and the vertical transfer units 52 are provided adjacent to the photodiodes 51 arranged in a line in a predetermined direction (the vertical direction in FIG. 6). The vertical transfer section 52 has four vertical transfer electrodes 52a, 52b, 52c, and 52d for one photodiode 51. Therefore, in the vertical transfer section 52, four potential wells can be formed, and signal charges can be output from the CCD 28 by controlling the depths of these wells as conventionally known. The number of vertical transfer electrodes can be freely changed according to the purpose.

A photodiode 51 is formed in a p-type well formed on the surface of the substrate 53, and the p-type well is completely depleted by a reverse bias voltage applied between the p-type well and the n-type substrate 53. You. In this state, charges corresponding to the amount of incident light (reflected light from the subject) are accumulated in the photodiode 51. When the substrate voltage Vsub is increased to a predetermined value or more, the electric charge accumulated in the photodiode 51 is discharged to the substrate 53 side. On the other hand, when a charge transfer signal (voltage signal) is applied to the transfer gate unit 54, the charges accumulated in the photodiode 51 are transferred to the vertical transfer unit 52. That is, after the charges are discharged to the substrate 53 side by the charge discharge signal, the signal charges accumulated in the photodiode 51 are transferred to the vertical transfer unit 52 side by the charge transfer signal. By repeating such an operation, signal charges are integrated in the vertical transfer unit 52, and a so-called electronic shutter operation is realized.

FIG. 8 is a timing chart of a distance information detecting operation for detecting data relating to the distance to each point on the surface of the subject. In the distance detection operation of the present embodiment, unlike the description of the principle of distance measurement performed with reference to FIG. 5 in order to reduce noise due to the influence of external light, reflected light is generated from the falling edge of the distance measurement light pulse. The timing chart is configured so that the state can be detected, and the state is switched to the undetectable state after the pulse of the reflected light has fallen, but this is not different in principle. 1, 2, 6 to 8
The distance information detecting operation in the present embodiment will be described with reference to FIG.

A charge discharge signal (pulse signal) S1 is output in synchronization with the output of a vertical synchronization signal (not shown), whereby unnecessary charges accumulated in the photodiode 51 are discharged toward the substrate 53. Then, the accumulated charge amount in the photodiode 51 becomes zero (reference S2). After the start of output of the charge sweeping signal S1, pulse-shaped ranging light S3 having a constant pulse width is output. The period (pulse width) during which the ranging light S3 is output can be adjusted.
The adjustment is performed so that the distance measurement light S3 is turned off simultaneously with the output of the charge sweeping signal S1.

The distance measuring light S3 is reflected by the object, and
It is incident on D28. That is, although the reflected light S4 from the subject is received by the CCD 28, the charge sweeping signal S1
Is not stored in the photodiode 51 (reference S2). Charge sweep signal S1
Is stopped, the photodiode 51 starts to accumulate charges by receiving the reflected light S4, and the reflected light S4
4 and signal charges S5 caused by external light are generated. Reflected light S
When 4 disappears (reference S6), the photodiode 51 ends the charge accumulation based on the reflected light (reference S7).
Charge accumulation due to only external light continues (reference S8).

Thereafter, when the charge transfer signal S9 is output, the charges stored in the photodiode 51 are transferred to the vertical transfer unit 52. This charge transfer is completed when the output of the charge transfer signal ends (reference S10). In other words, the charge accumulation in the photodiode 51 continues due to the presence of external light, but the signal charge S1 accumulated in the photodiode 51 until the output of the charge transfer signal ends.
1 is transferred to the vertical transfer unit 52. The charge S14 accumulated after the output of the charge transfer signal ends remains in the photodiode 51 as it is.

As described above, the period T from the end of the output of the charge sweeping signal S1 to the end of the output of the charge transfer signal S9.
_{During U1} , the photodiode 51 accumulates signal charges corresponding to the distance to the subject. Then, the reflected light S4
Until the end of the light reception (reference S6), the charges accumulated in the photodiode 51 are transferred to the vertical transfer unit 52 as signal charges S12 (hatched portion) corresponding to the distance information of the subject,
Other signal charges S13 are caused only by external light.

After a predetermined time has elapsed from the output of the charge transfer signal S9, the charge sweeping signal S1 is output again, and after the transfer of the signal charge to the vertical transfer section 52, the photodiode 51
Unnecessary charges accumulated in the substrate 53 are swept toward the substrate 53.
That is, accumulation of signal charges in the photodiode 51 is newly started. Then, as described above, when the charge accumulation period T _U1 has elapsed, the signal charge is transferred to the vertical transfer unit 52.

The vertical transfer section 5 of such signal charges S11
2 is repeatedly executed until the next vertical synchronization signal is output. As a result, in the vertical transfer unit 52, the signal charge S11 is integrated, and the signal charge S11 integrated in a period of one field (a period sandwiched between two vertical synchronization signals) is regarded as a period in which the subject is stationary. If possible, it corresponds to distance information to the subject.

The above-described operation of detecting the signal charge S11 relates to one photodiode 51, and such a detection operation is performed in all the photodiodes 51. As a result of the detection operation in the period of one field, the vertical transfer unit 52 adjacent to each photodiode 51
The distance information detected by the photodiode 51 is held in each of the parts. This distance information is output from the CCD 28 by a vertical transfer operation in the vertical transfer unit 52 and a horizontal transfer operation in a horizontal transfer unit (not shown).

However, the reflected light detected by the CCD 28 is affected by the reflectance of the surface of the subject. Therefore, the distance information obtained via the reflected light includes an error caused by the reflectance. In addition, the reflected light detected by the CCD 28 includes components such as external light in addition to the reflected light from the subject, and there is an error due to this. The method of correcting the error caused by the reflectance, the external light, and the like will be described in detail in the following description of the flowchart of the distance information detecting operation and the information transmitting operation.

FIGS. 12 to 14 are flowcharts of the distance information detecting operation and the information transmitting operation, and FIGS. 9 to 11 are timing charts in the detecting operation of the distance correcting information, the reflectance information and the reflectance correcting information.

When it is confirmed in step 101 that the release switch 15 is fully depressed, step 1 is executed.
02 is executed, video (V) mode and distance measurement (D)
It is determined which of the modes is selected. Switching between these modes is performed by operating the V / D mode switch 18. If the release switch 15 has not been fully pressed, this processing ends.

When the D mode is selected, in step 103, a vertical synchronizing signal is output, and distance measuring light control is started. That is, the light emitting device 14 is driven, and the pulse-shaped ranging light S3 is output intermittently. Next, step 104 is executed, and the detection control by the CCD 28 is started. That is, the distance information detection operation described with reference to FIG. 8 is started, and the charge sweeping signal S1 and the charge transfer signal S9 are alternately output, and the signal charge S of the distance information is output.
11 is integrated in the vertical transfer unit 52.

In step 105, it is determined whether one field period has elapsed from the start of the distance information detection operation, that is, whether a new vertical synchronizing signal has been output.
When one field period ends, integration of the signal charges S11 over one field period is completed, and the integrated signal charges are output from the CCD 28 in step 106. This integrated signal charge corresponds to the distance information, and is temporarily stored in the image memory 34 in step 107. In step 108, the ranging light control is switched to the off state, and the light emitting operation of the light emitting device 14 is stopped.

In steps 109 to 112, an operation of detecting distance correction information (see FIG. 9) is performed. First, in step 109, the vertical synchronizing signal is output and the CCD
28 starts detection control. That is, the light emitting device 1
In the state where the light source is turned off without performing the light emitting operation of No. 4, the charge discharge signal S21 and the charge transfer signal S22 are output alternately. The charge accumulation time T _U1 is the same as the distance information detection operation shown in FIG. 8, but since the object to be measured is not irradiated with the distance measurement light (reference S23), there is no reflected light (reference S24). Accordingly, no signal charge of the distance information is generated, but a disturbance component such as external light is incident on the CCD 28, so that a signal charge S25 corresponding to the disturbance component is generated.
By the output of the charge transfer signal S22, the signal charges S26 accumulated in the photodiode up to that time are transferred to the vertical transfer unit. This signal charge S26 corresponds to distance correction information for the charge accumulation time T _U1 for correcting the influence of the disturbance component on the distance information.

In step 110, it is determined whether one field period has elapsed from the start of the operation of detecting the distance correction information, that is, whether a new vertical synchronizing signal has been output. When one field period ends, integration of the signal charge S26 over one field period is completed, and step 11 is performed.
At 1, the integrated signal charge is output from the CCD 28. This integrated signal charge corresponds to the distance correction information, and is temporarily stored in the image memory 34 in step 112.

In steps 113 to 117, an operation of detecting reflectance information (see FIG. 10) is performed. Step 11
In 3, the vertical synchronization signal is output and the distance measurement light control is started, and the pulsed distance measurement light S33 is output intermittently. In step 114, the detection control by the CCD 28 is started, and the charge discharge signal S31 and the charge transfer signal S3
5 are output alternately. By outputting the charge sweeping signal S31, the accumulated charge amount in the photodiode becomes zero (reference S32). Charge sweep signal S31
Is completed, the ranging light S33 is output and the CCD
Is reflected light S34. After the reflected light S34 has disappeared, a charge transfer signal S35 is output. That is, the operation of detecting the reflectance information is performed such that all of the reflected light S34 is received within the charge accumulation period T _U2 from the end of the output of the charge sweep signal S31 to the end of the output of the charge transfer signal S35. Controlled.

As described above, in the photodiode, while the reflected light S34 is being received, the reflected light S34 and the signal charges S36 caused by the external light are accumulated, and while the reflected light S34 is not received, the external light is received. Signal charge S37 caused only by
S38 is accumulated. Then, by the output of the charge transfer signal S35, the signal charges S39 stored in the photodiode up to that time are transferred to the vertical transfer unit. This signal charge S39 corresponds to the reflectance information, and is a component S′3 based on external light.
9 is included.

In step 115, it is determined whether one field period has elapsed since the start of the reflectance information detection operation, that is, whether a new vertical synchronizing signal has been output. When one field period ends, one of the signal charges S39 becomes one.
The integration over the field period is complete and step 116
, The integrated signal charge is output from the CCD 28. This integrated signal charge corresponds to the reflectance information, and is temporarily stored in the image memory 34 in step 117. In step 118, the ranging light control is switched to the off state, and the light emitting operation of the light emitting device 14 is stopped.

In steps 119 to 122, the operation of detecting the reflectance correction information (see FIG. 11) is performed. In step 119, the vertical synchronizing signal is output and the CCD
28 starts detection control. That is, the light emitting device 1
In the state where the light source is turned off without performing the light emitting operation of No. 4, the charge sweeping signal S41 and the charge transfer signal S42 are output alternately. The charge accumulation time T _U2 is the same as that of the reflectance information detecting operation shown in FIG. 10, but since the object to be measured is not irradiated with the distance measuring light (reference S43), there is no reflected light (reference S44). Accordingly, no signal charge of the reflectance information is generated, but a signal charge S46 corresponding to a disturbance component such as external light is generated in the CCD 28. This signal charge S46
Corresponds to reflectance correction information for correcting the influence of the disturbance component on the reflectance information for the charge accumulation time T _U2 .

In step 120, it is determined whether or not one field period has elapsed since the start of the operation of detecting the reflectance correction information.
That is, it is determined whether a new vertical synchronization signal has been output. When one field period ends, the signal charges S47
Is completed over one field period of
At 21, the integrated signal charges are output from the CCD 28. The integrated signal charge corresponds to the reflectance correction information, and is temporarily stored in the image memory 34 in step 122.

In step 123, steps 103-1
The arithmetic processing of the distance data is performed using the distance information, the distance correction information, the reflectance information and the reflectance correction information obtained in step 22, the distance data is stored in the image memory 34 in step 124, and this detection operation is completed. Then, the information transmission operation of step 128 and subsequent steps is executed. On the other hand, when it is determined in step 102 that the V mode is selected, in step 125, the distance measuring light control is switched to the off state, and in step 126, a normal photographing operation by the CCD 28 (CCD video control)
Is set to the ON state, the image data captured in step 127 is stored in the image memory 34, this detection operation ends, and the information transmission operation of step 128 and subsequent steps is executed.

In steps 128 to 130, processing relating to the information transmission operation is performed. In step 128, it is determined whether the information transmission mode is set. If it is determined that the information transmission mode has been set, the process proceeds to step 129. On the other hand, when it is determined in step 128 that the information transmission mode is not set,
The data is recorded on the recording medium M in step 131, and then the process returns to step 101. The information transmission mode is set by operating the information transmission mode setting button 24. That is, once the information transmission mode setting button 24 is pressed, the information transmission mode is set, and when it is pressed again, the setting is released.

In step 129, it is determined whether the preparation for data transmission is completed. When the preparation for data transmission is completed, in step 130, the light emitting device 14 emits communication light pulse-modulated according to the modulation signal of the transmission data. When all the data has been transmitted, the process returns to step 101 and waits until the release switch 15 is fully pressed. Step 1
If it is determined in step 29 that the preparation for data transmission is not completed, step 129 is repeatedly executed, and waits until the preparation is completed.

Next, the contents of the arithmetic processing executed in step 123 will be described with reference to FIGS. It is assumed that a subject having a reflectance R is illuminated, and the subject is regarded as a secondary light source having a luminance I and is imaged on a CCD. At this time, the output Sn obtained by integrating the charge generated in the photodiode during the charge accumulation time t is represented by: Sn = kR.I.t (2) Here, k is a proportionality constant, which varies depending on the F number, magnification, and the like of the taking lens.

[0050] When the object is illuminated with light from a light source such as a laser, the luminance I becomes were synthesized with the luminance I _B by the luminance I _S and the background light due to the light source, I = I _S + I _B · ·・ (3)

As shown in FIG. 8, the charge storage time is T _U1 , the pulse width of the distance measuring light S3 is T _S , and the pulse width of the distance information signal charge S12 is T _D, and the charge storage during one field period is performed. When the time is to be repeated N times, the output SM _{10 obtained, SM 10 = Σ (k ·} R (I S · T D + I B · T U1)) = k · N · R (I S · T D + I _B · T _U1 ) (4) The pulse width T _D can be expressed as T _D = δ · t = 2r / C (5)

As shown in FIG. 10, the pulse-shaped charge accumulation time T _U2 is controlled to be sufficiently longer than the period (pulse width) T _{S of the} distance measuring light S23 and to include the entire unit light receiving time of the reflected light. output SM ₂₀ obtained when _{the, SM 20 = Σ (k ·} R (I S · T S + I B · T U2)) = k · N · R (I S · T S + I B · T U2) ·・ ・ (6)

Light emission is stopped as shown in FIG.
Output SM ₁₁ obtained when performing a pulsed charge accumulation at the same time width _{is, SM 11 = Σ (k ·} R · I B · T U1) = k · N · R · I B · T U1 (7) Similarly, the output SM ₂₁ obtained when performing charge accumulation as shown in Figure _{11, SM 21 = Σ (k ·} R · I B · T U2) = k · N · R · I B · T _U2 (8)

From the equations (4), (6), (7) and (8), S _D = (SM ₁₀ −SM ₁₁ ) / (SM ₂₀ −SM ₂₁ ) = T _D / T _S (9) ) Is obtained.

[0055] disturbance component of each outside light or the like and the distance measuring light S3 are in the reflected light S4 as described above (luminance I _B due to the background light)
It is included. T _D / T _{S in} equation (9) is the distance measuring light S3
The amount of reflected light S4 from the subject when the light is irradiated is normalized by the amount of distance measuring light S3, which is the amount of distance measuring light S3 (corresponding to signal charge S11 in FIG. 8).
The disturbance component (corresponding to the signal charge S'39 in FIG. 11) is calculated from the value obtained by removing the disturbance component (corresponding to the signal charge S26 in FIG. 9) from the light amount of the reflected light S4 (corresponding to the signal charge S39 in FIG. 10). Equal to the ratio with the value removed.

Each output value SM ₁₀ , SM ₁₁ , SM of the equation (9)
₂₀ and SM ₂₁ correspond to steps 107, 112, 117 and 122
, Are stored as distance information, distance correction information, reflectance information, and reflectance correction information. Therefore, T _D / T _S is obtained based on these pieces of information. Pulse width T _s
Is known, the distance r is obtained from the equation (5) and T _D / T _S.

FIG. 15 is a flowchart of the optical communication receiving operation executed on the computer 46.

First, the light receiver 47 is set so as to detect light in the frequency range in which the distance measuring light is modulated. When it is confirmed in step 201 that the distance measuring light has been received by the light receiver 47. , A timer is started in step 202. In step 203, it is determined whether a predetermined time has elapsed since the timer was started. If the predetermined time has not elapsed, it is determined in step 204 whether communication has started. That is, it is checked whether or not the light receiver 47 has detected the communication light modulated in a frequency range, for example, ten times the frequency of the distance measuring light. If the communication light has not been detected yet, it is determined again at step 203 whether the elapsed time of the timer has exceeded the predetermined time, and if it has exceeded the predetermined time, the process returns to step 201 and the next distance measuring light is detected. Wait until

For example, if the transmission start signal is detected by the photodetector 47 and it is determined in step 204 that the communication has been started, the optical signal transmitted from the camera is detected by the photodetector 47 in step 130, and the distance data and the The data is input to the computer 46 as image data. In step 205, it is determined whether the received signal is, for example, a transmission end signal. If the received signal is a transmission end signal, the receiving operation is terminated, and the process returns to step 201 to wait until the next distance measuring light is received. If not, the next signal is received.

[0060]

As described above, according to the present invention, a small and lightweight three-dimensional image detecting device which can transfer data to a computer without a cable and has good operability can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of a camera-type three-dimensional image detection device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of the camera shown in FIG.

FIG. 3 is a diagram schematically illustrating a state when a distance information detecting operation and an optical communication operation are performed.

FIG. 4 is a diagram for explaining the principle of distance measurement using distance measurement light.

FIG. 5 Distance measuring light, reflected light, gate pulse, and CCD
FIG. 4 is a diagram showing a distribution of the amount of light received by the light source.

FIG. 6 is a diagram illustrating an arrangement of a photodiode and a vertical transfer unit provided in a CCD.

FIG. 7 is a cross-sectional view of the CCD cut along a plane perpendicular to the substrate.

FIG. 8 is a timing chart of a distance information detecting operation for detecting data relating to a distance to a subject.

FIG. 9 is a timing chart of a detection operation of distance correction information.

FIG. 10 is a timing chart of an operation of detecting reflectance information.

FIG. 11 is a timing chart of the operation of detecting the reflectance correction information.

FIG. 12 is a flowchart of a distance information detecting operation and an optical communication operation.

FIG. 13 is a flowchart of a distance information detecting operation and an optical communication operation.

FIG. 14 is a flowchart of a distance information detecting operation and an optical communication operation.

FIG. 15 is a flowchart of an optical communication receiving operation executed by a computer.

[Explanation of symbols]

 14 light emitting device 51 photodiode

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G08C 23/04 H04N 7/18 A 5C061 H04N 5/225 7/22 5C064 G01B 11/24 K 5J084 7/18 G01S 17 / 02 A 7/22 G08C 23/00 A (72) Inventor Nobuhiro Tani 2-36-9 Maenocho, Itabashi-ku, Tokyo Asahi Gaku Kogyo Co., Ltd. F-term (reference) 2F065 AA04 AA06 AA53 BB05 DD02 FF04 FF12 FF32 FF41 GG06 GG08 JJ03 JJ26 LL06 LL30 MM22 PP04 PP22 QQ03 QQ14 QQ24 SS02 SS13 UU00 UU05 2F073 AA33 AB02 BB01 BC04 CC01 CD11 DD01 FF08 FG11 GG01 GG07 GG08 2F112 AD03 BA02 CA08 FA03 AC20 AB13 AC15 AB10 AB15 AC10 AC54 AC69 AC75 AC78 AC80 5C054 CA04 CC00 CH02 DA05 EA01 EA03 EC03 FF02 GA04 GD03 GD09 HA05 5C061 AB03 AB10 AB12 AB14 AB17 AB21 5C064 EA01 EA03 5J084 AA05 AD01 BA03 BA34 BA36 BB02 CA03 CA61 CA70 EA04

Claims (7)

[Claims] A light source for irradiating light; an image sensor capable of accumulating electric charge according to an amount of received light; illuminating the light source to irradiate a subject with ranging light; Distance information detecting means for detecting distance information to the subject by receiving light with an imaging element; information for controlling light emission of the light source, irradiating communication light with a space as a transmission path, and transmitting data to an external device A three-dimensional image detection device, comprising: a transmission unit. 2. The method according to claim 1, wherein the distance measuring light and the communication light have different pulse frequency modulation ranges.
Dimensional image detection device. 3. The three-dimensional image detecting apparatus according to claim 1, wherein the data is related to the distance information. 4. The three-dimensional image detecting apparatus according to claim 1, further comprising image information detecting means for forming an image of the subject by the image sensor and detecting image information of the subject. 5. The three-dimensional image detecting device according to claim 4, wherein the data is related to the image information. 6. The three-dimensional image detecting apparatus according to claim 1, wherein whether or not to drive the information transmitting means can be selected. 7. A reception control for receiving data transmitted by the communication light according to claim 1 is configured to start by receiving the distance measurement light according to claim 1. An optical communication receiver characterized by the above-mentioned.