JP2001075164A - Intra-finder display device and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intra-finder display device in which the confirmation of subjects is easy at the time of taking a photograph and which is capable of displaying photography information at a position where it is not a hindrance to the subjects at the time of observing the subjects, and a camera. SOLUTION: When the distance till a main subject is measured by a distance measuring part 12, the image of the main object in a screen is detected by an image detecting part 13. Then, in a CPU 11, the judgement of position of main object and the distance measuring operation are performed based on an output signal from the part 13 and the focusing control of a camera is performed. Moreover, an area where the main object does not exist is judged in the position judging part 11a of the CPU 11 by the operation for detecting the position of the main object of this image detecting part 13 and the displaying of the photography information in the area where the main object does not exist is controlled by a display part 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device in a finder and a camera, and more particularly to an improvement in a display device in a finder of a camera equipped with a multi-AF capable of measuring a plurality of points in a shooting screen. is there.

[0002]

2. Description of the Related Art In recent years, with the advancement of functions of cameras, a technique for displaying various information in a viewfinder has been developed.
For example, Japanese Patent Laying-Open No. 8-286353 discloses a camera that displays a focus point in a viewfinder in different colors.

Further, there is known a technique for displaying, in a finder screen, a shooting time and a battery state in a video camera as well as a point at which a camera measures a distance and luminance information. For example, as disclosed in Japanese Patent Application Laid-Open No. 7-87392, there is known a product that displays a screen of a broadcast of a back program at a corner of the screen even on a television or the like.

[0004] In the personal computer technology, a technology for selectively displaying various programs is widely known.

[0005] In other words, in order to solve the sensory problem that the user cannot see various displays at the same time, while visually recognizable visual information is easy to recognize, these ideas are devised. It has become indispensable.

[0006] In addition, at the time of commercialization, the display of digital images involves extremely large costs and difficulties in manufacturing. Therefore, it can be said that the idea of using this technology more effectively is a natural flow.

[0007]

However, the technique described in Japanese Patent Application Laid-Open No. 7-87392 relates to the arrangement of a plurality of broadcast images, and the user makes a judgment while watching the images. It is not a technology to operate.

In the case of a television screen, the above-mentioned plurality of screens are equivalent. In the case of a camera, however, one is a subject to be photographed, and the other is another screen, so that the former should be naturally emphasized. The latter need not look worst in the way.

However, the above-mentioned Japanese Patent Application Laid-Open No. Hei 8-28625
In the camera described in Japanese Patent Application Publication No. 3 (1993) -2009, if the display overlaps the main subject, the display in the viewfinder becomes very troublesome, for example, the expression of the subject becomes invisible.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above-mentioned problems, and provides a display device and a camera in a finder which are easy to confirm at the time of photographing and can display photographing information at a position where they do not interfere with observation of a subject. The purpose is to provide.

[0011]

That is, the present invention relates to a display device in a finder for displaying photographing information in a finder screen, a specifying means for specifying a distance measuring point in the finder screen, and the specifying means. Setting means for setting the position or size of the measured distance measurement point and the display of the photographing information so as not to overlap with each other.

Further, the present invention provides a display device in a finder for displaying photographing information in a finder screen, a determining means for determining a luminance distribution in the screen, and a luminance distribution information determined by the determining means. Setting means for setting the display position or size of the photographing information.

Further, the present invention provides a detecting means for detecting a gaze point of the photographer in the finder, a gaze change determining means for judging a change in the gaze point of the photographer based on the detection result of the detecting means, A display switching means for switching a display position, and a control means for switching and controlling the display switching means when the gaze change determining means determines that the gaze point has been changed.

In the finder display device according to the present invention, the photographing information is displayed in the finder screen, and the distance measuring points in the finder screen are specified by the specifying means. Then, the position or size of the specified distance measuring point is set by the setting means so that the specified distance measuring point does not overlap the display of the photographing information.

In the finder display device according to the present invention, the photographing information is displayed in the finder screen, and the luminance distribution in the screen is determined by the determination means. Then, based on the luminance distribution information determined by the determining means, the display position or size of the photographing information is set by the setting means.

Further, in the camera according to the present invention, the gaze point of the photographer in the finder is detected by the detection means, and based on the detection result of the detection means, the gaze change determination means determines the gaze point of the photographer. Is determined. When the display position in the finder is switched by the display switching means, if the gaze change determining means determines that the gaze point has been changed, the display switching means is switched by the control means.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

First, a display example in the finder by the finder display device of the present invention will be described.

According to the present invention, as shown in FIG. 2, the state of the subject in the finder is automatically determined. Therefore, the position and size of the information displayed on the screen can be switched. Camera.

FIG. 2A shows a simple composition in which the main subject 2 only exists at the center of the screen 1, and therefore, the distance measurement display 3a is output to an empty space at the upper left of the screen. This distance measurement display is one type of photographing information. For example, the photographer immediately outputs a visual image of a person in the case of a portrait distance and a display of a mountain in the case of a landscape distance. Make it easy to understand.

FIG. 2B shows an example of a scene display. In this case, since the free space in the screen 1 is small, the distance measurement display 3b is also reduced. Further, FIG.
As shown in (2), when no person exists at the center of the screen, the distance measurement display 3c is output at the center of the screen.

With such a device, the display does not overlap with the main subject, so that the user can sufficiently check the expression and composition of the subject, and whether the user has correctly focused. Can be confirmed on the same screen by the visual distance display, so shooting can be performed with confidence.

FIG. 1 is a block diagram showing a schematic configuration of the display device in the finder according to the first embodiment of the present invention.

In FIG. 1, a CPU 11 is an arithmetic and control means comprising a one-chip microcomputer or the like for controlling the sequence of the entire camera. The CPU 11 has a position determining unit 11a and an area determining unit 11b inside, and a distance measuring unit 12, an image detecting unit 13, and a display unit 14 are connected to the outside.

In this camera, when the distance to the main subject is measured by the distance measuring section 12, the image of the main subject on the screen is detected by the image detecting section 13. CPU
At 11, the main subject position is determined based on the output signal from the image detection unit 13 and the distance measurement operation is performed to control the focusing of the camera.

That is, the main object position detecting operation of the image detecting unit 13 causes the position judging unit 11 in the CPU 11 to operate.
The area where the main subject does not exist is determined in a, and display control is performed on the area where the main subject does not exist by the display unit 14 constituting the viewfinder.

If the CPU 11 monitors the image signal of the area where the main subject does not exist, the area of the displayable portion is determined by the area determination section 11b, and the size of the display portion is maximized. Display control becomes possible. FIG.
As shown in (b), when the low-contrast portion in the screen is narrow, the distance measurement display 3b is displayed small due to such control.

FIG. 3 is a flowchart for explaining the distance measuring operation of the camera according to the first embodiment.

When the image in the screen is detected in step S1, the position of the main subject is detected in step S2 based on the result. In detecting the main subject position, the distance of each part of the screen may be measured, and the closest distance may be selected from the distance distribution, or the determination may be made in consideration of the area or shape. Is also good. Alternatively, the determination may be made based on the pattern of the image or the distribution of the reflected light when the auxiliary light is applied.

In step S3, the image signal at the position of the main subject obtained in this manner is used to measure a distance for focusing. As described above, the content displayed in the finder at that time is switched according to the distance measurement result.

Next, in step S4, it is determined whether or not the main subject exists at the center of the screen based on the result of the main subject position determination in step S2. Here, if the main subject exists in the center of the screen,
In step S5, as shown in FIGS. 2A and 2B, a low-contrast space in the upper left portion of the screen is detected so that the distance measurement display is performed in the upper left space in the screen.

Then, in step S6, it is determined whether or not the space detected in step S5 is larger than a predetermined area. If the space is small, the process proceeds to step S7, and a small display (distance measurement display 3b) is output at the upper left of the screen as shown in FIG. 2B. If it is determined in step S6 that the space is large, the process proceeds to step S8, where a large display (distance measurement display 3a) is displayed at the upper left of the screen as shown in FIG. Is output.

On the other hand, if the main subject does not exist at the center of the screen in step S4, step S9
Then, as shown in FIG. 2 (c), a low-contrast space in the upper portion of the screen is detected so that the image is displayed in the upper portion of the center of the screen.

Then, in step S10, it is determined whether or not the space detected in step S9 is larger than a predetermined area. Here, if the space is small, the process proceeds to step S11, and a small display (not shown) is output in a portion on the center of the screen. If it is determined in step S10 that the space is large, the process proceeds to step S12, where a large display (a distance measurement display) is displayed in the upper center portion of the screen as shown in FIG. 3c) is output.

As described above, the position and size of the display are changed depending on the position of the main subject in the screen and the empty space of the display unit, so that a finder screen without troublesome display can be obtained.

In addition, as shown in FIG. 2B, when the display space is small, the display is small, so that it is possible to determine a shutter chance after confirming well every corner of the screen.

When the size of the empty space is large, the display is large, so that it is easier to confirm and the user can enjoy the photographing with a sense of security.

As described above, since the photographing information is not displayed at the position where the main subject is present, the expression of the person is not lost.

Next, a distance measuring device for a camera to which the above-described display device in a finder is applied will be described in detail.

Referring to FIG. 4A, a method of obtaining the subject distance will be described first.

In FIG. 4A, a light beam from a subject 20 is incident via light receiving lenses 21a and 21b and forms an image on sensor arrays 22a and 22b. Output signals from these sensor arrays 22a and 22b are
Is converted into a digital signal by an A / D conversion circuit 25a and supplied to a correlation operation unit 25b.

The CPU 25 is an arithmetic control means composed of a one-chip microcomputer and the like, and further includes an integration control section 25c and a selection section 25d. 27 is connected.

The light receiving lenses 21a and 21b have a parallax B
And a pair of light-receiving lenses arranged with
The image of 0 is formed on the sensor arrays 22a and 22b by the light receiving lenses 21a and 21b. This image is
According to the parallax B, images are formed at different relative positions on the two sensor arrays according to the principle of triangulation.

If the difference x between the relative positions is detected, the distance L to the subject 20 is calculated by calculating L = (B · f) / x according to the focal length f of the light receiving lenses 21a and 21b and the parallax B. Can be determined by: If the focusing unit 27 is controlled by the CPU 25 in accordance with the result, the user can enjoy shooting with the subject 20 in focus.

In the method of calculating x, the output of each sensor of each sensor array is stored as a digital signal in a memory (not shown) in the CPU by the A / D conversion circuit 25a provided in the CPU 25. Using this result,
In the CPU 25, a so-called correlation operation is performed by a predetermined program. This correlation calculation is a method of taking the difference while shifting the outputs of the two sensor arrays 22a and 22b in the direction in which the sensor arrays are arranged, and determining that the "correlation" of the shift amount when the difference becomes smallest is high. This shift amount and the pitch of the sensor array, that is, a value representing the relative position difference x described above. And this correlation operation is CP
This is performed in the correlation operation unit 25b in U25.

FIG. 5 is a configuration diagram showing a part of such a sensor array in more detail.

In FIG. 5, a bias circuit 3 serving as a power supply
1 is connected to the sensor arrays 32a to 32d. From these sensor arrays 32a to 32d, signal currents corresponding to the amounts of received light are output by the light receiving surfaces of the light receiving elements forming the sensor arrays. This signal current is guided to the integration amplifiers 34a to 34d when the integration switch 33a for switching the start / end of integration is turned on.

When the reset switch 33b is off, a voltage signal corresponding to the integration amount appears at the output of each of the integration amplifiers 34a to 34d. The result is read by the A / D conversion circuit 25a incorporated in the CPU 25, so that focusing can be performed through the above-described correlation operation.

However, the sensor arrays 34a to 34d
Since the amount of light entering varies depending on the brightness of the scene, the color of the subject, and the reflectivity, accurate integration is required in order to set the integration amount to an appropriate value with the limited dynamic range integration means. Control technology is required. For example, when the integration time is too short, the integration result becomes flat and no difference can be obtained, but when it is too long, the integration result becomes uniform due to the saturation of the circuit.

As is clear from the above description of the correlation calculation, if the image has little change, it is difficult to correlate the two images obtained by the two sensor arrays, and as a result, correct distance measurement cannot be performed. .

Therefore, a technique is used in which the integration result is monitored in real time and the integration is terminated when the integration level reaches an appropriate level. That is, which of the selection switches 33c connected to the maximum integration value detection circuit 35 is turned on determines which sensor output is monitored.

FIG. 6A is a timing chart for explaining the operation of performing the integral control by turning on the selection switch 33c.

When light enters the sensor arrays 32a to 32d, the reset switch 33b is turned on first, and after the output is reset to the reference level, the integration switch is turned on and the reset switch 33b is turned off. Integration is started at the timing of.

When the switch 8 of the selector 8 is connected to the maximum integration value output circuit 35, the output of the maximum integration value detection circuit 35 is selected as the output having the largest integration amount.
25 is input to an A / D conversion circuit 25a. Therefore, the CPU 25 outputs this output to the A / D conversion circuit 25a.
Are operated and monitored successively. If the integration switch 33 is turned off at the time T2 when this maximum value does not exceed the dynamic range of the circuit, the integrated output of each sensor will not exceed the dynamic range.

After stopping the integration, the sensor array 32
If the switches of the selection unit 8 are controlled to perform A / D conversion on the integrated outputs of a, 32b, 32c, and 32d,
Each sensor output can be sequentially monitored by the CPU 25.

The image signal thus obtained is shown in FIG.
As shown in (b), a dark part is represented as a low output and a bright part is represented as a high output according to the incident state of light. With this technology, camera ranging devices
An appropriate image signal can be obtained, and information for finding a contrast region suitable for displaying an image pattern on a screen can also be obtained.

Further, only the predetermined sensor is controlled by the switch 33c of the CPU 25 so that the maximum integrated value detecting circuit 35
And can be connected.

Here, even in the case of the above-described four sensors, as shown in FIG.
Assuming that the distance measuring point 28 is not the subject 20 and the light of the sun 29 enters as shown in FIG. 4C, if the sensor array 32a is not connected to the maximum integrated value detecting circuit 35, The integral control is not performed by the strong light of the sun.

On the other hand, if the direct light of the sun 29 affects the integration monitor, the integration control is usually terminated before the image signal of the subject 20 is obtained, so that accurate distance measurement cannot be performed in many cases. .

The same may occur even if the maximum integrated value detection circuit detects not the maximum value but the difference between the maximum value and the minimum value or the average value.

Further, in the configuration of the apparatus shown in FIG. 4A, when the light beam indicated by the broken line from the light receiving lens 21a is used, a point other than the point 28C at the center of the screen, that is, the base line is shifted in the longitudinal direction. Distance measurement of the points 28L and 28R is also possible.

As shown in FIG. 7 (a), the sensor arrays 22a and 22b disposed behind the light receiving lenses 21a and 21b are vertically moved one by one in the direction perpendicular to the base line length direction.
With this addition, it is possible to measure the distance between the point 28U and the point 28D, which are perpendicular to the base line length direction, like the light rays shown in FIG. Therefore, at this time, as shown in FIG. 7B, many points on the screen can be measured for distance, as schematically showing the monitor area of the sensor array.

If this idea is extended, as shown in FIG. 8A, the screen is not changed by using a so-called area sensor in which sensors are continuously arranged instead of one or three line sensors. The inside can be monitored all over, and for example, as shown in FIG. 7C, the number of measurable points can be increased to 30 or more.

By increasing the number of distance measurement points by such a device, it is possible to provide a distance measurement device capable of accurate distance measurement regardless of where the main subject exists on the screen.
For example, in the conventional method, only the center of the screen could be measured.
Even when there is a person near the edge of the screen in the composition shown in FIG. 3C, a camera capable of accurate focusing can be provided. Further, with this configuration, it is possible to measure the contrast and the luminance distribution of each part in the screen.

However, as described above, as the distance measurement range becomes wider, the influence of extra light is more likely to be exerted during integration control, and the probability of erroneous distance measurement as a side effect increases. Therefore, in the present embodiment, as shown in FIG.
While extending the ranging area to the entire screen, the integration judgment area
The pattern is limited to four patterns A to D, and the integral control is performed using only necessary light as much as possible.

That is, in the scenes shown in FIGS. 9A to 9D, it is determined whether the camera is held vertically, horizontally, or upward, and the optimum integration determination for the shooting situation is determined. If the integral control is performed using the region, the screen 38 in the figure can be displayed.
Appropriate integration control can be performed without being affected by the direct sunlight of the sun inside. Further, by this composition detection, it is possible to align the upper and lower sides of the displayed characters.

FIG. 9A is a horizontal composition and a composition not facing upward. Therefore, integration is determined in the integration determination area of the pattern A, and the process is terminated. FIG. 9B shows a vertical composition and a composition that is not upward, so that the pattern B is selected.

Further, when the camera is pointed upward, there are many cases in which a tall building or a mountain is to be photographed on the screen and the person in front of the camera is to be focused. In order to increase the angle of view, for example, a camera with a zoom lens often shoots on the wide angle side (Wide side) and does not shoot on the telephoto side (Tele side). In this case, as shown in FIGS. 9C and 9D, it is preferable to perform integration control by shifting the integration determination area downward in the screen. Above the center of the screen, there are many cases where there are objects with higher luminance than the main subject, such as the sky and the sun.

In FIGS. 9 (a) to 9 (d), 39a
To 39d are distance measurement displays displayed on the screen.

For the vertical and horizontal detection and the upward detection, as shown in FIG. 10, a spherical case 42 containing a fluid conductive material 43 such as mercury is built in a camera 41, and this case 42 Electrodes 44 inserted in
The determination can be made by the CPU which of the electrodes a to 44d is short-circuited by the fluid conductor.

That is, when the electrode 44b and the electrode 44c are short-circuited, the electrode 44b and the electrode 44a become horizontal, and when the electrode 44b and the electrode 44a are short-circuited,
4b and the electrode 44d can be determined to be upward.

In general, a camera with a zoom lens has a zoom position detection function because it is necessary to perform focus position correction control by zooming. Therefore, if this function or the like is applied and used, the camera can be used at the Tele side or the Wide side at the time of shooting. Can be determined. The use state of the camera is detected by the use state detection unit 26.

Here, with reference to the flowchart of FIG. 11, the distance measuring operation in the case of confirming the composition in the first embodiment will be described.

First, when the composition determination operation is performed in step S21, it is determined in subsequent step S22 whether or not the composition is a vertical composition. Here, in the case of the horizontal composition, the process proceeds to step S23, and in the case of the vertical composition, the process proceeds to step S30.

In step S23, the telephoto side (T
ele side) is determined. Here, if it is on the telephoto side (Tele side), the process proceeds to step S25,
Otherwise, it is determined in step S24 whether the camera is facing upward. If it is not upward, the process proceeds to step S25, and if it is upward, the process proceeds to step S26.

In step S25, integral control is performed as the area sensor pattern A described above. Similarly, in step S26, integral control is performed as the pattern D of the area sensor.

Next, in step S27, FIG.
As shown in the above, image correlation is obtained for 30 or more points, and distance measurement is performed. Then, step S2
When the closest distance is selected in step 8, a horizontal composition in which the screen is horizontal can be obtained in step S29.

If it is determined in step S22 that the image is a vertical composition, the flow shifts to step S30 to determine whether or not the photographing is on the telephoto side (Tele side). If the camera is on the telephoto side (Tele side), the process proceeds to step S32. If not, it is determined in step S31 whether the camera is facing upward. If not upward, the process proceeds to step S32, and if upward, the process proceeds to step S33.

In step S31, integral control is performed as the area sensor pattern B described above. Similarly, in step S33, integral control is performed as the pattern C of the area sensor.

Next, in step S34, FIG.
As shown in the above, image correlation is obtained for 30 or more points, and distance measurement is performed. Then, step S3
When the closest distance is selected in step 5, a vertical composition with the screen set to vertical can be obtained in step S36.

In this way, the subject image can be correctly detected by the integral judgment optimal for each scene. After the integral control, the distance measurement is performed by obtaining the image correlation at the above-mentioned 30 points in the screen. If the closest distance is set as the main subject distance, correct focusing and display position determination can be performed.

Also, the vertical and horizontal composition judgment is made so that the upper and lower sides of the display are aligned, so that it is always easy to see. Further, the photographing information display can be confirmed in the viewfinder.

In addition to such composition determination, FIG.
As shown in FIG. 2 and FIG. 13, an optimal integration determination region may be selected from the output of the area sensor.

In a screen 47 capturing a scene as shown in FIG. 12A, the upper half of the screen is empty, so that there is a high probability that the main subject exists somewhere in the lower half of the screen. .

In order to judge this automatically, FIG.
As shown in FIG. 12 (b), an area sensor is considered based on x and y coordinates, and the output luminance values of pixels having the same y value along the x direction are added and displayed as a graph.
As shown in (c), the output luminance values of the pixels having the same x value along the y direction are added to compare the added luminance distribution when the graph is displayed.

In this case, since the sky and the earth are separated in FIG. 12B, a large change in luminance indicated by ΔBV is observed. However, in FIG. Becomes Most of these large luminance changes are y
Detected as _B.

On the other hand, in the vertical composition as shown in FIG. 13 (a), conversely, a large change in ΔBV is seen in the added luminance distribution added in the y direction (FIG. 13 (b)), and the same in the x direction. Only a monotonous change is seen in the added luminance distribution obtained by adding the output values of the sensor area having the value of y (FIG. 13).
(C)). Similar to the example shown in FIG. 12, a majority was a large luminance change and x _B.

By using such characteristics and selecting an integral judgment area in accordance with the flowchart of FIG.
As shown in (a) and (b), the integration determination regions 51a and 51b can be provided in most of the space except for the empty space.
In addition, the distance measurement display units 52a and 52b can be provided in the space.

If x _B and y _B cannot be detected, it is sufficient to determine the end of integration at the center of the screen as shown in FIG. 15C where the probability that the main subject exists is high. In this case, the distance measurement display section may be displayed in an orthodox horizontal upper left display as shown in FIG.

Therefore, FIGS. 12 (a) and 13 (a)
12D and FIG. 13 from the screen shown in FIG.
As shown in (d), the distance measurement displays 48a and 48b are output.

Next, the above-described operation of selecting an integration area will be described with reference to the flowchart of FIG.

First, in step S41, a pre-integration operation for selecting an integration determination area is performed to check the state of the screen. As shown in FIGS. 12 and 13, the integration control may be performed by using the sensor pixel that outputs the maximum output among the sensor pixels of the entire screen. The control may be performed based on a typical value.

Then, in step S42, when the output values of the pixels having the same y value along the x direction are added, the pattern is determined in the following step S43.

Next, in step S44, it is determined whether or not there is an empty portion. Here, when the hollow portion exists, the process proceeds to step S45, the integral determination is made by the straight line y = y _B / 2 parts. Then, step S4
At 6, a distance measurement display is made in the sky as a side of the screen, that is, as a horizontal composition.

On the other hand, if it is determined in step S44 that there is no empty space, steps S47 and S48 are performed.
Then, the output values of pixels having the same x value along the y direction in the y direction are added to determine the pattern in the same manner as in the x direction.

Then, in step S49, it is determined again whether or not there is an empty space. Here, when the hollow portion exists, the process proceeds to step S50, the integral determination is made by the straight line x = x _B / 2 parts. Then, in step S51, a distance measurement display is made in the sky as a vertical screen, that is, as a vertical composition.

If it is determined in step S49 that the area is not empty, the flow shifts to step S52 to perform integral control on the center of the screen. Then, step S53
In this case, the distance measurement display is performed at the upper left of the screen, that is, as a horizontal screen.

With this configuration, the switch for determining the composition and the tilt of the camera as shown in FIG. 10 described above is not required.

When the integration area is selected in this way, the sky portion is automatically detected, and the distance measurement display is performed on that portion, so that the user is not able to confirm the subject in the finder.

Next, as a second embodiment of the present invention, a camera to which a display device in a finder is applied will be described in further detail in consideration of parallax and the like.

FIGS. 16A and 16B show a second embodiment of the present invention. FIG. 16A is a block diagram showing the internal configuration of the camera, and FIG. 16B is an external perspective view of the camera.

In FIG. 16A, a CPU 55 is an arithmetic control means comprising a one-chip microcomputer or the like for performing camera sequence control and various arithmetic operations.
The CPU 55 includes an image detecting unit 56 and a correlation calculating unit 5 therein.
7 and a display control unit 58.

A switch group 59 composed of a release switch and the like is connected to the CPU 55,
1 and a photometric unit (not shown) are connected.

The distance measuring unit 61 includes a driver 62 for driving the light projecting unit 63, a light projecting unit 63 for projecting distance measuring light to a subject (not shown), and a light receiving lens for guiding reflected light from the subject. 21a and 21b, sensor arrays 22a and 22b for forming an image of the reflected light, and an A / D for A / D converting signal outputs of the sensor arrays 22a and 22b.
And a converter 64.

The CPU 55 further includes an exposure control unit 6.
5, a focusing unit 66, a zoom detecting unit 68 for detecting the position of the zoom lens 67, and a finder optical system 71.
A display liquid crystal (LCD) 70 inserted in the camera and a visual line detection unit 72 for detecting the visual line of the photographer are connected.

As shown in FIG. 16B, a camera body 75 is provided with a photographing lens 76 on the front surface thereof, and a distance measuring window 77, a finder 78, a strobe 79, and the like. I have.

As described above, the CPU 55 controls the photometric unit and the distance measuring unit 61 (not shown), and controls the exposure control unit 65 and the focusing unit 66 according to the output.
Take photos with the correct exposure and correct exposure. When the zoom lens 67 is used as the photographing lens 76 of the camera, the angle of view can be changed. Therefore, the zoom information is input to the CPU 55 by the zoom detector 68 that detects the zoom position. Further, the finder 78 is zoomed.
Images are also mechanically linked.

In order to display the various information thus obtained on the LCD 70 provided between the finder optical systems, the CPU 55 has a display control unit 58 for controlling the turning on and off of these segments. I have.

The distance measuring section 61 includes a pair of light receiving lenses 21.
a, 21b and a pair of sensor arrays 22a, 22b. The A / D converter 64 performs A / D conversion of an image signal of a subject (not shown), and outputs the converted signal to the CPU 55.

Since the light receiving lenses 21a and 21b are arranged apart from each other by a distance B corresponding to the base line length serving as parallax, the two sensor arrays are determined based on the relationship between the focal length f of the light receiving lenses 21a and 21b and the object distance L. On 22a and 22b,
The same image is formed at a position shifted by the relative position x. From the principle of the triangulation, it can be understood that the object distance L can be calculated by obtaining the image shift amount x.

To measure a wide area of the screen,
For example, when measuring the distance from the optical axis by θ,
As shown by a broken line in the figure, the relative displacement may be detected with reference to the sensor at a = ftan θ (1).

With a camera having such a configuration, FIG.
In a scene where the main subject 82 does not exist at the center of the finder screen 81 as shown in FIG.

FIG. 17 (b) shows an image signal obtained in such a scene. A characteristic image signal change is observed at a person whose background is a main subject from a wall or the like. . Therefore, if this change is detected in the flow chart as shown in FIG. 18 and the change is detected on the right side of the screen, if the right LCD segment of the LCD segments 83 in the finder screen is turned on, it is shown in FIG. like,
A distance measurement point is displayed on the screen, and a subject to be photographed correctly is measured. The photographer can recognize that the subject is in focus, and can enjoy photographing with ease.

That is, in the flowchart of FIG. 18, when an image signal of a subject is input in step S61, left and right edges are determined in subsequent steps S62 and S63. Next, in step S64, the coordinates of the central portion of the left and right edges determined in steps S62 and S63 are determined.

Then, the LCD segment having the coordinates determined here is selected in step S65, for example, as shown in FIG.
The light is turned on as shown in FIG. Further, in step S66, the distance measurement information is output as the distance measurement display 84 to the sky portion where the main subject 82 does not exist in the finder screen 81.

As described above, the distance measuring points are represented by cross-shaped segments, and the central portion thereof is made visible, so that the expression of the subject and the like can be easily confirmed, and a clear screen can be obtained.

In a scene as shown in FIG. 19, there is a case where the camera erroneously focuses on a tree in front. In this case, the photographer may switch to the next distance measuring point candidate by pressing an operation button (not shown).

For example, since 80% or more of the photographs have a main subject at the center of the screen, in this embodiment, the distance measurement point is moved to the center of the screen by a change operation to correctly focus on the castle of the subject. Was made possible. In response to this, the display position of the distance measurement display is switched (84a, 8).
4b) It is also possible.

In addition, since this operation is difficult to change using a finger, it is possible to construct and use a finder optical system based on line-of-sight detection as shown in FIG.

That is, in the finder optical system 86, the image of the subject incident from the objective lens 87 is used together with the prism 88 and the infrared light emitting diode (IRED) 89 through the eyepiece 92 to the eyes of the photographer. Irradiated with infrared light. Then, the reflected light is received by the photodiode (PD) 90 via the mask LCD 91.

The mask LCD 91 is positioned in the optical path as shown in FIG.
As shown in (c), the opening 94 is arranged to be switched. By switching the openings of the mask LCD 91, it is possible to determine which of the openings is the most reflected light incident and to determine the direction of the line of sight. It is possible to switch the ranging point by using.

For example, in the arrangement of the eye 93 as shown in FIG. 21A, since there is a white eye portion in the openings of S1 and S3, when the openings of S1 and S3 are opened, the photodiode is connected to the photodiode. Incident signal light reflected by the IRED increases.

However, when the line of sight is shifted as shown in FIG. 21B, the signal light of S3 decreases and the reflected light when the opening of S2 is opened increases. After the photographer presses the release button halfway and displays the first candidate, if the CPU of the camera controls the IRED and the mask in a flow chart as shown in FIG. When the photographer wants to switch the ranging point, the user simply moves his or her eyes, and the ranging point is switched, so that a manual operation is not required.

Referring to the flowchart of FIG. 22, first, in step S71, image detection is performed and a first candidate is displayed. Next, in step S72, if the second release switch has been turned on, the flow shifts to step S73 to execute a normal photographing sequence.

On the other hand, if the second release switch has not been turned on, the flow shifts to step S74 to irradiate the infrared light emitting diode 89. Then, step S75
In steps S76 and S76, the openings are sequentially changed, and two blocks S ₀₁ and S ₀₂ having large reflected signal light are stored.

Next, in step S77, the two blocks S ₀₁ and S ₀₂ are compared. As a result, if there is a change, it is determined that the line of sight has changed, and the flow shifts to step S78 to determine whether or not the change has been made once. Where 1
If the number of times has not changed, the flow shifts to step S79 to change the distance measurement point and the display point in the finder corresponding thereto.

That is, two blocks with a large amount of reflected signal light are selected while sequentially opening all the openings two times, and it is determined whether or not the line of sight has moved based on whether or not the interval changes. If there is a movement of the line of sight, the photographer determines that he or she likes the distance measurement point, switches the display to the next highest priority point, measures the distance, and focuses on that point. Make adjustments. If the photographing display position in the viewfinder is switched accordingly, the distance measurement display does not interfere.

As a result, the photographer can be freed from troublesome manual operations and can concentrate on the release operation, and can select a distance measuring point or change the distance measuring display position only by eye movement. However, if the display position is switched by only a slight movement of the eyes, the display flickers. Therefore, the switching may be performed only when the same movement is performed twice.

It is also possible to determine the point seen by the photographer and focus on that point.
It turns out that, despite the complexity and cost of the technology, photographers do not always see what they want to photograph.

For this reason, according to the present invention, the camera automatically determines in advance the priority order among the distance measurement points on the screen,
In addition to this, the movement or operation such as the movement of the eyes of the photographer is added in the form of addition or assistance, so that extremely simple and highly accurate focusing can be achieved.

If the finder and the AF light-receiving lens are different optical systems, an error is likely to occur between the distance measurement point and the display point due to parallax (parallax).

Here, with reference to FIG. 23, a description will be given of an in-screen display control method in consideration of the above-described parallax.

[0133] by the main subject position detection by image signals previously discussed, it is determined that there are the main subject in the direction of the theta ₁ in FIG. 23, besides the distance of the object is being detected in the manner described above, this When L is set, the subject is seen at the position of SL-tan θ ₁ (2) on the right side with respect to the optical axis in the viewfinder. Here, S is the parallax of the two optical systems.

The reference position in the viewfinder is set at the end of the screen (FIG. 2).
3), the distance from this reference position to the finder optical axis is L ₁ tan φ ₁ (3) (where φ ₁ is the angle of view of the finder from the optical axis) angle to the end), from the reference position, the distance to the point becomes _{L 1 tan φ 1 + S-} L 1 tan θ 1 ... (4).

Here, it is assumed that the display LCD is of a dot matrix type, and the entire screen is shown in FIG.
As shown in FIG. 4, it is assumed that an LCD that can be filled with H segments is contained in the finder.
Since the H number corresponds to twice the L ₁ tan θ ₁ , the segment corresponding to the distance measuring point is H × (tan φ ₁ + S / L-tam θ ₁ ) / (2・ Tan φ ₁ ) th = x _1st (5) Note that H was removed from the above equation (5) (tan φ
₁ + S / L-tam θ ₁ ) / (2 · tan φ ₁ )
It is referred to as a frame ratio.

Therefore, if this segment is turned off and the upper, lower, left and right segments are turned on two by two, FIG.
The display of the segment as shown in FIG.

Further, the state of the subject can be easily seen by the light-off control. If the distance measurement points can be extended in the vertical direction of the screen, it is necessary to control the display in the viewfinder in consideration of not only the horizontal frame ratio (frame ratio 1) but also the vertical frame ratio (frame ratio 2). is there.

As shown in FIG. 25, assuming that the vertical angle of view is φ ₂ and the distance measuring point is θ ₂ , the ratio of the distance measuring point position to the angle of view based on the upper end of the screen frame (frame ratio 2) since _{(tan φ 2 -tan θ 2)} / 2tan φ 2 ... become (6), as shown in FIG. 24 (a), assuming an LCD lined T segments within the screen vertically From the top, it is considered that the subject exists at the segment of T (tan φ ₂ −tan θ ₂ ) / (2 · tan φ ₂ ) = y ₁ ... (7).

Therefore, when the display as shown in FIG. 24 (b) is moved up and down, lighting and extinguishing control is performed in the vertical direction from this relationship.

That is, when expressed in the xy coordinate format, the points of (x ₁ , y ₁ ) = (H × frame ratio 1, T × frame ratio 2) are turned off, and the upper and lower two segments are turned on. By doing so, the display as shown in FIG. 24 (b) can be moved up, down, left and right, and the distance measurement light can be easily transmitted to the photographer.

Further, the above-mentioned light-off point is not limited to one point, and in order to make the expression of the subject in the distance measuring point better visible, the light-off point is switched and controlled according to the distance, the angle of view and the like. Is effective.

That is, the width of the human face is K (about 20 cm).
When, as shown in FIG. 26 (a), the distance L and the screen width of the x direction obtained by the angle phi ₁ representing the angle 2L
・ The ratio of K to the tan φ ₁ is occupied in the screen. Accordingly, in the case of a dot matrix type LCD having H dots in the horizontal direction, if the turn-off control for H × K / 2L · tan φ ₁ is performed, as shown in FIGS. By controlling the light-off area according to the size of the face
It can make people's facial expressions well visible.

The operation of turning on the display in the viewfinder in such a case will be described with reference to the flowchart of FIG.

First, in step S81, φ ₁ and φ ₂ are obtained by determining the zoom state of the camera. Next, in step S82, the distance measuring directions θ ₁ and θ are detected by the distance measuring sensor.
₂ is required. From these, in step S83, the coordinates (x ₁ , y ₁ ) of the main subject in the screen are calculated by the CPU of the camera according to the above formula.

Then, distance measurement is performed in step S84. Assuming that the result is L, in step S85, the face width occupies the upper, lower, left, and right sides of (x ₁ , y ₁ ) from the above relationship.
× halves segment of K / 2L · tan φ ₁ is turned off. Further, by turning on the upper, lower, left and right segments in step S86, the segments 96a and 96b can be displayed clearly as shown in FIG. 13B.

In step S87, the shooting information 97a, 97b is set based on the empty space in the finder screen.
The size of the graphic display and numerical display is changed.

If the proportion of the person occupied by the face width or the like of the main subject is determined, other blank areas are also obtained, so that the photographed content having a size corresponding to this area may be displayed.

In the display example according to the second embodiment, the distance distribution is three-dimensionally displayed on the screen.
When the distance of each part is obtained by distance measurement of the entire screen, as shown in FIGS. 26B and 26C, in a scene where only one person stands, the shape of the person appears. It can be displayed in various forms. The higher the point, the closer the distance.

With such a display, it is possible to visually notify that each point is accurately measuring the distance and that the camera is accurately detecting the subject, so that the user can continue shooting with peace of mind. In addition, a high-tech feeling can be provided, and a fun camera can be provided just by looking at the display without photographing.

Further, what is displayed on the display unit is not limited to one piece of information. As shown in FIGS. 26B and 26C, the lower half is provided with the exposure control which has been known for a long time. The shutter speed, the aperture (FNo) at the time of photographing, and the like may be displayed side by side.

The CPU calculates these values from the photometric value and the film sensitivity.

As described above, by devising the switching of the light-off portion, the photographer can know where on the screen the subject is in focus, and after confirming the expression of the subject sufficiently, the photographer can feel safe. It is possible to provide a camera that allows users to enjoy shooting.

Although FIG. 26 shows an example in which the number of subjects is one, the number of subjects may be detected from image information or the like, and the light-off control may be performed accordingly. In this case, the camera can be used to clearly understand the expressions of the people standing side by side.

As described above, the method of detecting the point of the main subject on the screen and specifying the location while giving a certain degree of visibility to the portion is not limited to the cross-shaped ranging points. As shown in FIGS. 28 (a), (b), and (c), it is also possible to apply an oblique cross, a round shape, a square shape, or the like in the finder. These distance measuring points can be changed in size according to the size of the face.

Further, in the case of a dot matrix type LCD, dots can be switched and displayed in a finder visual field like a grid, so that such an application can be dealt with only by modifying the software of the CPU.

Of course, the display method may be switched according to the user's preference, or may be switched for each sales channel in consideration of regional characteristics.

In addition, by utilizing the advantages of the dot matrix, a configuration may be employed in which a character display is output in the viewfinder as shown in FIG. Such a configuration is useful for commercialization that is easy for the user to understand.

Naturally, it is troublesome if the character display is applied to the main subject. Therefore, the part where the character display is output is also used for the part which is not the main subject by using the main subject detection technology which is a feature of the present invention. Select and display a bright space. Alternatively, the size of the display may be switched according to the clear space.

FIG. 29 is a flow chart for explaining the operation of display in the viewfinder when the size of such a character display can be changed.

First, when a main subject is detected in step S91, an empty space other than the main subject is detected in the finder in the following step S92. Then, in step S93, the size of the character to be displayed is determined. Next, in step S94, the above-mentioned step S92 is placed on the empty space detected in step S92.
The character having the size determined in step 93 is displayed.

In addition to the display for focusing and exposure control, which has been known for a long time, the display for photographing information is shown in FIG.
FIG. 28 (b) shows a flash charging display shown in FIG.
It is convenient if there are information displays such as a battery remaining amount display shown in FIG. 28 and a solar cell charge display shown in FIG.

While the strobe is being charged, the exposure will not be correct even if the shutter is turned on during the time that the energy for the strobe is stored in the capacitor. Therefore, an hourglass mark is output as an image display to inform the user of the standby state. Also, when the battery level is getting low,
As shown in FIG. 28, displaying the image of the battery eliminates the possibility of missing a chance to replace or charge the battery.

FIG. 30 is a diagram showing a schematic configuration of a camera capable of displaying the above-mentioned solar battery charge as a third embodiment of the present invention.

In FIG. 30, the camera body 101
For example, a solar cell 102 is provided on the upper surface, and a power supply cell 104 is connected via a rectifier circuit 103.
The rectifier 103 is connected to a filter 105, a voltage dividing resistor 106, and a CPU 110 having a built-in A / D converter via a switch 107.

The CPU 110 includes a display unit 111 for displaying information, a photometric unit 112, a charging circuit 113 to which a charging capacitor 114 is connected, and a light emitting unit 115.
Is connected. In addition, a strobe 116 is connected to the charging circuit 114 and the light emitting unit 115. still,
117 is a taking lens.

In such a camera that can charge the power supply battery 104 using the solar battery 102, the camera can be charged with energy when the sun is shining. This state may be displayed as an image as an information display as shown in FIG. If this display is output, the user can enjoy shooting without worrying about the remaining battery level.

The voltage of the power supply battery 104 is
Is turned on and the voltage is divided by the voltage dividing resistor 106, the CPU 110
A / D conversion circuit enables battery check. Further, the CPU 110 determines the shutter speed and the aperture based on the output of the photometry unit 112. In a situation where camera shake is likely to occur, the flash unit 116 emits light to assist exposure.

The strobe 116 discharges the energy charged in the charging capacitor 114 by the light emitting section 115 to emit light.
No. 4 takes a long time to be charged by the charging circuit 113. Therefore, if it is determined that the charging time is in progress, it takes time until the next photographing, and the display is as shown in FIG. 28A.

These displays are controlled by the CPU 110 according to the flowchart shown in FIG. However, in this flowchart, the display location selection sequence is omitted.

First, when the check is started in step S101, the state of the battery check is determined in the following step S102. Here, as a result of the battery check, if the remaining amount of the power supply battery 104 is not low, the process proceeds to step S103, and an indication that the remaining amount is low is displayed.

At step S104, the state of solar cell 102 is determined. Here, if the voltage of the solar cell 102 is sufficient, the process proceeds to step S105 and a mark representing the solar cell is displayed.

In step S106, it is determined whether or not strobe 116 is being charged. If the strobe 116 is charging, the process proceeds to step S107, and a charging mark is displayed.

Thereafter, in step S108, it is determined whether or not the release switch has been turned on. If the release switch is turned on, step S
The flow shifts to 109, where a shooting sequence is executed.

As described above, according to the third embodiment, since the state at the time of shooting can be displayed as an image in the viewfinder, it is possible to provide a camera that allows the user to easily understand the operation and shoot with ease. Become.

According to the above-described embodiment, a camera which has a sense of security at the time of photographing and which makes it easy to confirm the photographing state by the display in the viewfinder which does not hinder the visual sense at the time of selecting the composition at the time of the important photographing. Can be provided.

In the above-described embodiment, only an example of a silver halide camera has been described. However, it goes without saying that the present invention can be applied to an electronic camera or a video camera having an electronic viewfinder.

According to the above embodiment of the present invention,
The following configuration can be obtained.

(1) In a finder display device of a camera for displaying photographing information in a finder screen, specifying means for specifying a distance measuring point in the finder screen; A display device in a camera finder, comprising: a setting unit for setting a position or a size of a point so that the display of the shooting information does not overlap.

(2) In a finder display device of a camera for displaying photographing information in a finder screen, a judging means for judging a luminance distribution in the screen, and a judgment means for judging luminance distribution information judged by the judging means. And a setting means for setting a display position or a size of the photographing information.

(3) The display device in the viewfinder of the camera according to (1) or (2), wherein the photographing information is information in which a photographing mode and a focusing distance are graphically displayed.

(4) The camera finder according to (1) or (2), wherein the photographing information is a battery state for driving the camera, a charging time during flash charging, or a charging standby state. Display device inside.

(5) The display device according to the above (1) or (2), wherein the photographing information is a distance distribution in a screen.

[0183]

As described above, according to the present invention, it is possible to provide a display device in a finder and a camera which can be easily checked at the time of photographing and can display photographing information at a position where it does not interfere when observing a subject. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a display device in a finder according to a first embodiment of the present invention.

FIGS. 2A and 2B illustrate an example in which the state of a subject in a finder is automatically determined. FIG. 2A illustrates a composition in which a main subject is present at the center of a screen, and FIG. FIG. 3C is a diagram showing an example, and FIG. 3C is a diagram showing an example in which no person exists at the center of the screen.

FIG. 3 is a flowchart illustrating a distance measuring operation of the camera according to the first embodiment.

4A is a diagram illustrating a configuration of a distance measuring device of a camera to which a display device in a finder is applied, FIG. 4B is a diagram illustrating an example in which a distance measuring point of a sensor array is in a subject,
(C) is a diagram showing an example in which the distance measurement point of the sensor array is in sunlight.

FIG. 5 is a configuration diagram showing a part of the sensor array in more detail.

FIG. 6A is a timing chart illustrating an operation of performing integral control by turning on the selection switch 33c, and FIG. 6B is a diagram illustrating an example of an output of an image signal monitored by a CPU.

7A is a diagram showing an arrangement of a light receiving lens and a sensor array, FIG. 7B is a diagram schematically showing a monitor area of the sensor array in FIG. 7A, and FIG. It is a figure showing the monitor area at the time of making into 30.

8A is a diagram illustrating an arrangement of a light receiving lens and a sensor array, and FIG. 8B is a diagram illustrating an example in which a ranging area is arranged over the entire screen.

FIG. 9 is a diagram illustrating an example of a screen composition, an integration determination area, and a distance measurement display.

FIG. 10 is a diagram for explaining vertical / horizontal detection and upward detection.

FIG. 11 is a flowchart illustrating a distance measuring operation when confirming a composition in the first embodiment.

FIG. 12 is a diagram illustrating an example of a case where an optimal integration determination area is selected from an output of an area sensor.

FIG. 13 is a diagram illustrating an example of a case where an optimal integration determination area is selected from an output of an area sensor.

FIG. 14 is a flowchart illustrating an integration area selection operation.

FIG. 15 is a diagram illustrating an example of a screen composition, an integration determination area, and a distance measurement display.

FIG. 16 shows a second embodiment of the present invention.
(A) is a block diagram showing an internal configuration of a camera,
(B) is an external perspective view of the camera.

FIG. 17 is a diagram illustrating an example of distance measurement in a scene in which a main subject does not exist at the center of the finder screen.

FIG. 18 is a flowchart illustrating a display operation of a distance measurement point according to the second embodiment.

FIG. 19 is a diagram illustrating an example of a case where the focus is incorrectly focused on a tree in front of the subject, instead of the main subject.

FIG. 20 is a diagram showing a configuration of a finder optical system based on line-of-sight detection.

21 is a diagram illustrating the relationship between the mask LCD of FIG. 20 and the movement of the photographer's eyes.

FIG. 22 is a flowchart illustrating an operation of a first release according to the second embodiment.

FIG. 23 is a diagram for describing an in-screen display control method in consideration of parallax.

FIG. 24 is a view for explaining an LCD in a finder serving as a distance measuring point.

FIG. 25 is a diagram for describing an in-screen display control method in consideration of parallax.

FIG. 26 is a diagram for explaining the operation of turning on the display in the viewfinder in consideration of parallax.

FIG. 27 is a flowchart illustrating an operation of turning on display in the viewfinder when the width of a human face is taken into consideration.

FIG. 28 shows a display example in the viewfinder.
(A) is a diagram illustrating an example of a ranging point by a cross-hatched line, (b) is a diagram illustrating an example of a round ranging point,
(C) is a diagram showing an example of a square shaped ranging point,
(D) is a diagram showing an example of character display.

FIG. 29 is a flowchart for explaining the operation of display in the viewfinder when the size of character display can be changed.

FIG. 30 is a diagram showing a schematic configuration of a camera capable of performing the above-described solar cell charge display as a third embodiment of the present invention.

FIG. 31 is a flowchart illustrating a display operation of camera shooting information according to the third embodiment.

[Explanation of symbols]

 1 screen, 2 main subjects, 3a, 3b, 3c distance measurement display, 11, 25 CPU, 11a position determination unit, 11b area determination unit, 12 distance measurement unit, 13 image detection unit, 14 display unit, 20 subjects, 21a, 21b light receiving lens, 22a, 22b, 32a to 32d sensor array, 25a A / D conversion circuit, 25b correlation operation unit, 25c integration control unit, 25d selection unit, 26 use state detection unit, 27 focusing unit, 28 distance measurement points 31 bias circuit, 33a integration switch, 33b reset switch, 33c selection switch, 34a-34d integration amplifier, 35 maximum integration value detection circuit, 41 camera, 42 case, 43 conductive material, 44a-44d electrode.

Claims (4)

[Claims] 1. A display device in a finder for displaying photographing information in a finder screen, a locating means for specifying a distance measuring point in the finder screen, the specified distance measuring point and the photographing information Setting means for setting the position or size of the display so that the display does not overlap with the display. 2. A finder display device for displaying photographing information in a finder screen, comprising: a determination means for determining a luminance distribution in the screen; and a luminance distribution information determined by the determination means. Setting means for setting the display position or size of the photographing information. 3. The photographing information includes information indicating a photographing mode and a focusing distance in graphic form, a battery state for driving a camera, a charging time during flash charging or a charging standby state,
3. The display device in a finder according to claim 1, wherein the display device is at least one of distance distributions in a screen. A detecting means for detecting a gaze point of the photographer in the viewfinder; a gaze change determining means for determining a change in the gaze point of the photographer based on the detection result of the detecting means; and a display position in the viewfinder. A camera comprising: display switching means for switching; and control means for switching and controlling the display switching means when the gaze change determination means determines that the gaze point has been changed.