JP2000121922A - Object display device for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always accurately check the depth of a field without making a finder dark. SOLUTION: An object is irradiated with range-finding light by a light emitting device 14. Reflected light from the object is received by a CCD 38. A signal electric charge is integrated at the photoelectric conversion element of the CCD 38, so that three-dimensional information which is a distance from a camera to each point on the surface of the object is detected. The histogram of the distance is obtained, so that a part substantially focused at the object is displayed based on the peak value of the histogram.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for displaying a focused object on a finder screen.

[0002]

2. Description of the Related Art Conventionally, in photographing using, for example, a single-lens reflex camera, focus adjustment is usually performed on an image located at the center of a finder screen. However, since the aperture of the aperture, that is, the depth of field is different between the time of observation of the finder screen and the time of shutter release, only by looking into the finder screen, it is necessary to determine the in-focus range in the photographed picture. Is difficult. Therefore, a camera with a preview function has been proposed in the past. In this camera, when the preview lever is operated, the aperture of the aperture changes to the size at the time of shooting, and the depth of field can be monitored from the viewfinder screen Becomes

[0003]

However, in the preview, since the aperture of the aperture is small, the viewfinder screen becomes too dark depending on the brightness of the subject, making it difficult to see, and it is difficult to accurately check the depth of field. It can be difficult.

It is an object of the present invention to provide a subject display device which can always check the depth of field accurately without darkening the viewfinder screen.

[0005]

According to the present invention, there is provided a camera subject display apparatus comprising: a light source for irradiating a subject with distance measuring light; and a plurality of photoelectric sensors for receiving reflected light from the subject and accumulating charges corresponding to the amount of received light. An imaging element having a conversion element; three-dimensional information detection means for detecting three-dimensional information that is a distance from the camera to each point on the surface of the subject by integrating signal charges in the photoelectric conversion element; Means for calculating the depth of field based on the size of the aperture; means for obtaining, for each distance, a histogram indicating the frequency of appearance of photoelectric conversion elements that output signals at that distance; and determining the histogram based on the depth of field and the histogram. And a focused portion display means for displaying a substantially focused portion of the subject.

[0006] The three-dimensional information detecting means is, for example, a signal charge holding portion provided adjacent to the photoelectric conversion element and an unnecessary charge accumulated in the photoelectric conversion element is swept out of the photoelectric conversion element to stop its operation. A stored charge sweeping means for starting a signal charge storage operation in the photoelectric conversion element, a signal charge transfer means for transferring the signal charge stored in the photoelectric conversion element to a signal charge holding unit, a stored charge sweeping means, and a signal charge transfer A signal charge integration means for integrating the signal charge in the signal charge holding unit by alternately driving the means.

The photoelectric conversion element is preferably of a charge storage type. The photoelectric conversion element is formed, for example, along the substrate, and the accumulated charge sweeping means sweeps out unnecessary charges to the substrate side. Preferably, the signal charge holding unit is a vertical transfer unit for outputting the signal charge to the outside of the three-dimensional image detection unit. The photoelectric conversion element and the signal charge holding unit are configured as an interline CCD having a vertical overflow drain structure.

Preferably, a charge sweeping signal output by the accumulated charge sweeping means for sweeping out unnecessary charge and a charge transfer signal output by the signal charge transferring means for transferring the signal charge are pulse signals. It is. In this case, the pulse of the ranging light having a predetermined pulse width is output by the light source, and the pulse of the ranging light is output during the charge accumulation period from when the charge sweeping signal is output to when the charge transfer signal is output. By being output, the signal charge corresponding to the three-dimensional information is integrated in the signal charge holding unit.

The in-focus portion display means displays the in-focus portion based on, for example, the maximum peak value of the histogram. The focused portion display means may display the focused portion based on a ratio of a plurality of peak values included in the histogram. Further, the focused portion display means may display a portion corresponding to one of the plurality of peak values included in the histogram as a focused portion.

The in-focus portion display means may include a liquid crystal monitor. In this case, the liquid crystal monitor displays the in-focus portion at a luminance different from other portions. The in-focus portion display means may include a liquid crystal panel provided in the optical path of the optical viewfinder. In this case, the liquid crystal panel is controlled so that the in-focus portion is in a transmission state.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a camera provided with a subject display device according to a first 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. A light emitting device (light source) 14 for irradiating a laser beam, which is a distance measuring light, is provided on the upper surface of the camera body 10 and directly above the taking lens 11. A release switch 15 and a liquid crystal display panel 16 are provided on the left side of the light emitting device 14, and a mode switching dial 17 is provided on the right side. The mode switching dial 17 switches the shooting operation mode of the camera between an aperture priority mode, a shutter speed priority mode, a program shooting mode, and the like.

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.

A first mirror 31 is provided behind the photographing lens 11 (right side in the figure), and a second mirror 32 is provided further behind the first mirror 31. First mirror 3
Reference numeral 1 denotes a half mirror, and the second mirror is a total reflection mirror. Each of these mirrors 31 and 32 is rotatable between an inclined position indicated by a solid line and a horizontal position indicated by a broken line.

An optical viewfinder 33 is provided above the first mirror 31. The viewfinder 33 includes a focus plate 34, a liquid crystal panel 35, and an eyepiece 36. The focus plate 34 and the liquid crystal panel 35 are superimposed on each other, and are provided at a position where the first mirror 31 at the horizontal position is opposed to the first mirror 31. The eyepiece 36 is provided in the viewfinder 33 on the side opposite to the focus plate 34 and the liquid crystal panel 35.

The liquid crystal panel 35 includes a liquid crystal panel driving circuit 37.
, Whereby the individual liquid crystal cells are independently switched between a state in which light is transmitted and a state in which light is not transmitted. When the first mirror 31 is in the inclined position, an image obtained through the photographing lens 11 is formed on a focusing plate 34. The part of the image corresponding to the part of the liquid crystal panel 35 in the transmission state is the eyepiece 3
6, the portion corresponding to the non-transparent portion of the liquid crystal panel 35 is displayed dark. On the other hand, when the first mirror 31 is at the horizontal position, nothing is imaged on the focus plate 34. The liquid crystal panel drive circuit 3
7 is controlled by the imaging signal processing circuit 47 based on the distance measurement result, as described later.

An image sensor (CC) is provided below the second mirror 32.
D) 38 is provided, and a shutter 41 is provided behind the second mirror 32. Behind the shutter 41, a film 42 for recording a captured image is disposed. The CCD 38 can detect an image for one screen obtained by the photographing lens 11, that is, the same image as the image guided to the film 42, and is used for distance measurement. That is, when the second mirror 32 is in the inclined position, the image obtained by the photographing lens 11 is
The distance is formed using this image, and three-dimensional information, which is the distance from the camera to each point on the surface of the subject, is detected. On the other hand, when the second mirror 32 is at the horizontal position, the light that has passed through the photographing lens 11 is guided to the film 42 by opening the shutter 41, and an image is recorded. The opening / closing operation of the shutter 41 is controlled by a shutter driving circuit 43.

A light emitting element control circuit 52 is connected to the system control circuit 51. 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 light emitting element control circuit 52. The light emitting element 14a irradiates a laser beam, which is a distance measuring light, and this laser beam is radiated to a subject via an illumination lens 14b. Light reflected by the subject enters the photographing lens 11. The distance is measured by detecting this light by the CCD 38.

In the distance measurement, electric charges corresponding to the formed image are generated in a large number of photoelectric conversion elements provided in the CCD 38. Operations such as a charge accumulation operation and a charge read operation in the CCD 38 are controlled by the CCD drive circuit 44. The charge signal, that is, the image signal, read from the CCD 38 is amplified by the amplifier 45, and is converted from an analog signal to a digital signal by the A / D converter 46. The digital image signal is subjected to processing such as noise reduction in an imaging signal processing circuit 47 and is temporarily stored in a three-dimensional information memory 48.

Iris drive circuit 26, lens drive circuit 2
7, the shutter drive circuit 43, the CCD drive circuit 44, and the imaging signal processing circuit 47 are controlled by the system control circuit 51. The system control circuit 51 includes a release switch 15, a mode switching dial 17,
A switch group 53 including the manual selection switch 18 and the liquid crystal display panel 16 for displaying a photographing operation mode of the camera and the like are connected.

Referring to FIGS. 3 and 4, the principle of distance measurement in the present embodiment will be described. In FIG. 4, 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 distance measuring light and the reflected light have traveled twice the distance r between the distance measuring device T 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 reflected light can be detected from the rise of the distance measuring light pulse 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,
The distance from the camera body 10 to each point on the surface of the subject S is detected by detecting the received light amount A at each of a plurality of photodiodes (photoelectric conversion elements) provided in the CCD 38 and arranged two-dimensionally. , Subject S
The data of the three-dimensional image relating to the surface shape is input collectively.

FIG. 5 is a diagram showing the arrangement of the photodiode 61 and the vertical transfer unit 62 provided on the CCD 38.
FIG. 6 is a cross-sectional view showing the CCD 38 cut along a plane perpendicular to the substrate 63. The CCD 38 is a conventionally known interline type CCD, and uses a VOD for sweeping out unnecessary charges.
(Vertical overflow drain) method.

The photodiode 61 and the vertical transfer section (signal charge holding section) 62 are formed along the surface of the n-type substrate 63. The photodiodes 61 are two-dimensionally arranged in a lattice shape, and the vertical transfer units 62 are provided adjacent to the photodiodes 61 arranged in a line in a predetermined direction (vertical direction in FIG. 5). The vertical transfer unit 62 includes four vertical transfer electrodes 62 a and 62 for one photodiode 61.
b, 62c and 62d. Therefore, in the vertical transfer section 62, four potential wells can be formed, and signal charges can be output from the CCD 38 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 61 is formed in a p-type well formed on the surface of the substrate 63, and the p-type well is completely depleted by a reverse bias voltage applied between the p-type well and the n-type substrate 63. You. In this state, charges corresponding to the amount of incident light (reflected light from the subject) are accumulated in the photodiode 61. When the substrate voltage Vsub is increased to a predetermined value or more, the charges accumulated in the photodiode 61 are discharged to the substrate 63 side. On the other hand, when a charge transfer signal (voltage signal) is applied to the transfer gate section 64, the charges accumulated in the photodiode 61 are transferred to the vertical transfer section 62. That is, a so-called electronic shutter operation is realized by sweeping the charges to the substrate 63 side by the charge sweeping signal and then transferring the signal charges accumulated in the photodiode 61 to the vertical transfer unit 62 by the charge transfer signal.

FIG. 7 is a timing chart of a three-dimensional information detecting operation for detecting data relating to the distance to each point on the surface of the subject. The three-dimensional information detecting operation will be described with reference to FIGS.

An electric charge sweeping signal (pulse signal) S2 is output in synchronization with the output of the vertical synchronizing signal S1, whereby unnecessary charges accumulated in the photodiode 61 are removed from the substrate 63.
In the direction of The light emitting device 14 is activated simultaneously with the end of the output of the charge sweeping signal S2, and the pulse-shaped ranging light S3 having a constant pulse width is output. The distance measuring light S3 is reflected on the subject and enters the CCD 38. That is, the reflected light S4 from the subject is received by the CCD. When a certain time has elapsed from the output of the distance measuring light S3,
A charge transfer signal (pulse signal) S5 is output, whereby the charges accumulated in the photodiode 61 are transferred to the vertical transfer unit 62. The output of the charge transfer signal S5 is
This is performed before the output of the ranging light is completed.

As described above, the output of the charge sweeping signal S2 is terminated.
T until the output of the charge transfer signal S5 starts._U1of
Between the object and the photodiode 61
The corresponding signal charges are accumulated. That is, the distance measuring light S3 is emitted.
Forced period T_SAnd charge accumulation period T_U1Start at the same time
Is the charge accumulation period T_U1Ends earlier and the reflected light S4
Only a part is detected by the CCD 38 and the detected light
Signal charge S6 caused by the distance to the subject
are doing. In other words, the reflected light S4 from the subject
That is, the charge accumulation period T_U1Reach photodiode 61 inside
The signal charge S6 corresponding to the emitted light is
Is accumulated in This signal charge S6 is a charge transfer signal S5
Is transferred to the vertical transfer unit 62. Note that the distance measuring light S3
Output period T _SIs the charge accumulation period T_U1Start earlier than
Is also good.

After a predetermined time has passed from the output of the charge transfer signal S5, the charge sweeping signal S2 is output again, and after the transfer of the signal charge to the vertical transfer unit 62, the photodiode 61
Unnecessary charges accumulated in the substrate 63 are swept toward the substrate 63.
That is, the accumulation of signal charges in the photodiode 61 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 62.

The vertical transfer section 63 of such signal charges S6
Is repeatedly executed until the next vertical synchronization signal S1 is output. As a result, in the vertical transfer unit 62, the signal charge S6 is integrated, and the signal charge S6 integrated during the period of one field (the period sandwiched between the two vertical synchronization signals S1) assumes that the subject is stationary during that period. If it can be considered, it corresponds to the three-dimensional information of the subject.

The operation of detecting the signal charge S6 described above is 1
One of the photodiodes 61 performs such a detection operation in all the photodiodes 61. As a result of the detection operation in the period of one field, each portion of the vertical transfer unit 62 adjacent to each photodiode 61 has the 3
Dimension information is retained. The three-dimensional information is output from the CCD 38 by the vertical transfer operation of the vertical transfer unit 62 and the horizontal transfer operation of the horizontal transfer unit (not shown).

FIGS. 8 and 9 show a case where one of a plurality of subjects included in a picture to be photographed is selected and the automatic focus adjustment and the automatic exposure control are performed on the selected subject by using the above-described principle of distance measurement. 4 is a flowchart of a program for performing shooting.

In step 101, the parameter n is set to 0. In step 102, the release switch 15
Is pressed halfway, that is, whether the photometry switch is set to the ON state. When the release switch 15 is half-pressed, the routine proceeds to step 103, where distance measurement is performed.

In step 103, the light emitting device 14 and the CC
D38 is driven, and three-dimensional information on all objects included in the screen to be captured is detected. That is, CC
The distance to each point to the object is detected by each photodiode of D38, and stored in the three-dimensional information memory 48. In step 103, a histogram related to the distance as shown in FIG. 10, for example, is created based on the three-dimensional information. In this histogram, the horizontal axis indicates the distance from the camera to each point on the surface of the object, and the vertical axis indicates the number of pixels corresponding to the distance, that is, the number of photodiodes that have detected the distance. In other words, the histogram indicates, for each distance, the appearance frequency of the photodiode that outputs a signal at that distance.

[0037] At step 104, the distance the distance D ₁ which takes the largest peak value H ₁ in the histogram is determined, and defined as significant distance Da which corresponds to the object to be imaged. In step 105, it is determined whether the significant distance Da is infinity, that is, whether 1 / Da ≒ 0. When the significant distance Da is at infinity, that is, when most of the image obtained by the CCD 38 is at infinity, the significant distance Da does not indicate the distance to the subject to be actually photographed. As a result, in steps 106 to 108, the significant distance Da is reset.

[0038] At step 106, the distance D ₂ which takes a peak value H ₂ the second largest in the histogram is determined. In step 107, the ratio (H ₂ / H ₁₎ whether greater than a predetermined value (for example, 1 or less) is determined. This ratio is
Subject image at a distance D ₂ indicates the ratio with respect to the background in the infinity. When the ratio is greater than a predetermined value,
Subject to be photographed is considered to be in the distance D _2, in step 108 the distance D ₂ is defined as a significant distance Da. In step 107, the value H ₂ (the number of pixels)
May be determined as to whether or not the percentage of the total number of pixels in one screen is greater than a predetermined value.

In step 111, automatic focusing is performed on the subject to be photographed, the photographing lens 11 is driven and displaced in the optical axis direction, and the focus is adjusted to the significant distance Da. In step 112, the CCD 38 is driven,
The luminance value of each pixel is detected using a photodiode corresponding to the significant distance Da. Photometry is performed by integrating these luminance values, that is, the luminance values of the image of the subject to be photographed, and the exposure conditions such as the aperture and the shutter speed at the time of photographing are obtained. That is, in step 112, automatic exposure control is performed.

In step 113, the depth of field Δd is obtained from the exposure condition (ie, aperture) obtained in step 112. In step 114, the liquid crystal panel 35 is driven, and the liquid crystal cell corresponding to the pixel whose distance falls within the range of (Da ± Δd) is set to the transmission state, and the other liquid crystal cells are set to the non-transmission state. As a result, as shown in FIG. 11, the subject SS in the range of (Da ± Δd) is substantially focused, and is clearly observed by the viewfinder 33. (Parts attached) becomes unclear. Therefore, the photographer can identify the subject SS on which the focus adjustment and the exposure control are performed.

In step 115, the release switch 1
It is determined whether 5 has been fully pressed. When the release switch 15 is not fully pressed, step 116 is executed, and it is determined whether the manual selection switch 18 has been set to the ON state. The manual selection switch 18 is a switch for manually selecting a subject to be focused. When the manual selection switch 18 is off, steps 115 and 116 are repeatedly executed. During this time, when the release switch 15 is fully pressed,
The photographing operation is executed in steps 1 to 123. When the manual selection switch 18 is set to the ON state, the photographing operation is performed in step 11
Proceeding to 7, the subject to be focused is changed.

In step 117, the parameter n is incremented by one. At step 118, it is determined whether or not the parameter n is 5 or less. That is, the distance Dn having the n-th largest peak value is set as the significant distance Da.
Then, the process returns to step 111, and the above-described operation is performed for the significant distance Da. Step 1
If it is determined in step 18 that the parameter n exceeds 5, the parameter n is set to 0 in step 119, and the process returns to step 117. That is, in this embodiment, the parameter n can be set in the range of 1 to 5.

On the other hand, in step 121, the aperture 25 is stopped down from the fully opened state to the opening corresponding to the exposure condition, and the first mirror 31 and the second mirror 32 are set to the horizontal state. In step 121, the shutter 41 is opened. Thus, the film 42 is exposed. In step 122, it is determined whether the exposure time (shutter speed) determined in step 112 has elapsed. If the exposure time has elapsed, step 123
Is executed. That is, the shutter 41 is closed, the first mirror 31 and the second mirror 32 are each set to the inclined state, and the diaphragm 25 is returned to the fully open state. Thus, the program ends.

As described above, according to the present embodiment, a subject to be focused can be selected from a plurality of objects included in one screen by a simple operation without performing an operation such as a focus lock. it can. Further, according to the present embodiment, the subject within the depth of field (Da + Δd) can be accurately identified without narrowing the aperture down to a predetermined value by a so-called preview operation.

FIG. 12 is a block diagram showing a circuit configuration of a digital camera having a subject display device according to the second embodiment. The basic configuration is the same as that of the first embodiment shown in FIG. 2, and different configurations will be described.

The CCD 38 is disposed behind the photographing lens 11 and directly faces the photographing lens 11, and is not provided with a mirror and a shutter as in the first embodiment. An image memory 71 and an LCD drive circuit 72 are connected to the imaging signal processing circuit 47 in addition to the three-dimensional information memory 48.
A liquid crystal monitor 73 is connected to the D drive circuit 72.
The three-dimensional information memory 48 stores information on the distance to the subject, while the image memory 71 stores image data obtained by a shooting operation. On the other hand, the liquid crystal monitor 73 is controlled by the LCD drive circuit 72,
38 can be displayed. That is, the liquid crystal monitor 73 functions as a finder. Still images can be displayed on the liquid crystal monitor 73 in accordance with the image data stored in the image memory 71.

A memory card controller 74 is connected to the system control circuit 51, and a memory card 75 can be mounted on the memory card controller 74.
The image data stored in the image memory 71 is transferred and recorded on the memory card 75.

The other configuration is the same as that of the first embodiment.

FIGS. 13 and 14 show a memory card 7 according to the second embodiment, in which a subject is selected for photographing.
5 is a flowchart of a program for recording in No. 5. The processing contents of steps 201 to 208 are the same as those of steps 101 to 108 shown in FIG. That is,
A significant distance Da, which is a distance to a subject to be actually photographed, is obtained based on a histogram related to three-dimensional information of a plurality of subjects included in one screen.

In step 211, the subject to be photographed is subjected to automatic focus adjustment, the photographing lens 11 is driven and displaced in the optical axis direction, and the focus is adjusted to the significant distance Da. In step 212, the CCD 38 is driven,
The luminance value of each pixel is detected using a photodiode corresponding to the significant distance Da. Then, photometry is performed by integrating these luminance values, and the exposure conditions of the aperture and shutter speed at the time of photographing are obtained. In step 212, image data obtained from all photodiodes is stored in the image memory 71.

In step 213, the depth of field Δd is obtained from the exposure condition (ie, aperture) obtained in step 212. In step 214, the liquid crystal monitor 73 is driven, and the area where the distance falls within the range of (Da ± Δd) is displayed in a normal state, but the other areas are displayed.
By shifting the image data by one bit,
Appears dark. This allows the photographer to recognize the subject on which focus adjustment and exposure control are performed.

The processing contents of steps 215 to 220 are the same as those of steps 115 to 120 shown in FIG. That is, by operating the manual selection switch 18, the subject to be adjusted in focus can be manually selected.
If it is detected that 5 is fully pressed, step 2
Proceed to 21. That is, the aperture 25 is stopped down from the fully opened state to the opening corresponding to the exposure condition,
8 is driven and exposed for a time corresponding to the shutter speed obtained in step 212. The image data thus obtained is temporarily stored in the image memory 71, read out from the image memory 71 in step 222, and recorded on the memory card 75. This allows
This program ends.

As described above, the second embodiment is an example in which the present invention is applied to a digital camera, and the same effects as those of the first embodiment applied to a silver halide camera can be obtained.

[0054]

As described above, according to the present invention, it is possible to always accurately check the depth of field without darkening the viewfinder screen.

[Brief description of the drawings]

FIG. 1 is a perspective view of a camera provided with a subject display device according to a first 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 for explaining the principle of distance measurement using distance measurement light.

FIG. 4 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. 5 is a diagram showing an arrangement of a photodiode and a vertical transfer unit provided in a CCD.

FIG. 6 is a cross-sectional view of the CCD cut along a plane perpendicular to the substrate.

FIG. 7 is a diagram for detecting data relating to the distance to the subject 3
6 is a timing chart of a dimension information detection operation.

FIG. 8 is a first half of a flowchart of a program for selecting one of a plurality of objects as a subject to be photographed and performing automatic focus adjustment and automatic exposure control on the subject;

FIG. 9 is a latter half of the flowchart of the program shown in FIG. 8;

FIG. 10 is an example of a histogram relating to distance.

FIG. 11 is a block diagram illustrating an example of a screen observed by a finder.

FIG. 12 is a block diagram illustrating a circuit configuration of a digital camera including a subject display device according to a second embodiment.

FIG. 13 is a first half of a flowchart of a program for selecting one of a plurality of subjects and performing automatic focus adjustment and automatic exposure control in the second embodiment.

FIG. 14 is a latter half of the flowchart of the program shown in FIG. 13;

[Explanation of symbols]

 14 Light-emitting device (light source) 38 Image sensor

Continued on the front page F term (reference) 2H011 AA01 BA41 BB02 BB04 BB05 DA05 2H051 AA02 BB27 CB17 CB22 CE25 DA15 DA26 EB06 GA01 GA03 GA09 2H054 BB11 CA02 CA03 CA15 CC01 CD03 5C022 AA13 AB02 AB12 AB24 AC03 AC42 AC80

Claims (13)

[Claims] A light source for irradiating a subject with distance measuring light; an image sensor having a plurality of photoelectric conversion elements for receiving reflected light from the subject and accumulating electric charges according to an amount of received light; Three-dimensional information detecting means for detecting three-dimensional information that is a distance from the camera to each point on the surface of the subject by integrating the signal charge; and a depth of field based on the size of the diaphragm at the time of shooting. Means for obtaining, for each distance, means for obtaining a histogram indicating the frequency of appearance of the photoelectric conversion element that outputs a signal of the distance, based on the depth of field and the histogram, substantially in the subject A subject display device for a camera, comprising: a focus portion display means for displaying a focus portion. 2. The method according to claim 1, wherein the three-dimensional information detecting means includes a signal charge holding unit provided adjacent to the photoelectric conversion element, and an unnecessary charge accumulated in the photoelectric conversion element being swept out of the photoelectric conversion element to perform an operation. An accumulation charge sweeping means for starting an operation of accumulating signal charges in the photoelectric conversion element by stopping the operation; a signal charge transfer means for transferring the signal charges accumulated in the photoelectric conversion element to the signal charge holding unit; 2. The signal charge integration unit according to claim 1, further comprising a signal charge integration unit that integrates the signal charge in the signal charge holding unit by alternately driving the stored charge sweeping unit and the signal charge transfer unit. Camera subject display device. 3. The apparatus according to claim 2, wherein the photoelectric conversion element is of a charge storage type. 4. The apparatus according to claim 2, wherein said photoelectric conversion element is formed along a substrate, and said accumulated charge sweeping means sweeps out unnecessary charges toward said substrate. 5. The signal charge holding section reduces the signal charge by three.
3. The apparatus according to claim 2, wherein the apparatus is a vertical transfer unit for outputting to the outside of the three-dimensional image detection unit. 6. The photoelectric conversion element and a signal charge holding unit,
Interline CC with vertical overflow drain structure
3. The apparatus according to claim 2, wherein the apparatus is configured as D. 7. A charge sweeping signal output by the accumulated charge sweeping means and sweeping out the unnecessary charge, and a charge transfer signal output by the signal charge transferring means and transferring the signal charge. The subject display device for a camera according to claim 2, wherein each of the signals is a pulse signal. 8. A pulse-like ranging light having a predetermined pulse width is output by the light source, and during the charge accumulation period from the output of the charge sweep signal to the output of the charge transfer signal, 8. A signal charge corresponding to three-dimensional information is integrated in the signal charge holding unit by outputting a pulse of distance measuring light.
2. A subject display device for a camera according to claim 1. 9. The subject display device for a camera according to claim 1, wherein the in-focus portion display means displays an in-focus portion based on a maximum peak value of the histogram. 10. The apparatus according to claim 1, wherein the in-focus portion display means displays an in-focus portion based on a ratio of a plurality of peak values included in the histogram. 11. The camera subject according to claim 1, wherein the in-focus portion display means displays a portion corresponding to one of a plurality of peak values included in the histogram as an in-focus portion. Display device. 12. The camera subject according to claim 1, wherein the in-focus portion display means includes a liquid crystal monitor, and the liquid crystal monitor displays the in-focus portion at a brightness different from other portions. Display device. 13. The apparatus according to claim 1, wherein the in-focus portion display means includes a liquid crystal panel provided in an optical path of an optical finder, and the liquid crystal panel is controlled such that the in-focus portion is in a transmission state. Item 2. A subject display device for a camera according to Item 1.