JPH05224116A - Camera - Google Patents

Abstract

PURPOSE:To provide a camera in which errors in photographing are decreased to the closest distance under a fixed condition and which is provided with an effective closest warning display function. CONSTITUTION:A central part range-finding circuit 101 measures a distance to an object in the center part in a photographic image frame, and the distances to the object on left and right peripheries in the center part are measured by a left peripheral part range-finding circuit 102a and a right peripheral part range-finding circuit 102b. Whether or not the result of range-finding by the circuit 101 shows a closer distance than a previously set value is decided by a central part distance decision circuit 103, and whether or not the results of range-finding by the circuits 102a and 102b show the closer distance than the previously set value is decided by a left peripheral part distance decision circuit 104a and a right peripheral part distance decision circuit 104b. Based on the decided result, a warning display control circuit 108 controls a display circuit 109 to display warning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having a multi-point distance measuring function for measuring a plurality of points in a photographing image frame, particularly a subject distance on a short distance side.

[0002]

2. Description of the Related Art Conventionally, a camera having a multi-point distance measuring device having a multi-point distance measuring function for measuring object distances at a plurality of points in a photographing image frame has been used.

As a multipoint distance measuring device used in a conventional camera, as disclosed in Japanese Patent Laid-Open No. 1-288813, a distance measuring point detecting the closest distance among a plurality of distance measuring results. If the distance measurement result of 1 is closer than the preset threshold value, there is a method of focusing on the second closest distance measuring point.

Another method is disclosed in Japanese Patent Laid-Open No. 2-272.
As disclosed in Japanese Laid-Open Patent Publication No. 526, there is a method of controlling the extension of the taking lens based on the distance measurement result of the central portion when the distance measurement result of the central portion is very close.

[0005]

In the conventional multi-point distance measuring apparatus described above, the photographer mistakenly composes the main subject at a distance closer than the close limit distance while intending to shoot the close subject. In the case of a failure, there is a problem in that all distance measurement information is calculated, even though it is originally desired to focus on the short distance side, and the focus is set on the long distance side.

The present invention has been made in view of the above problems, and provides a camera capable of reducing shooting errors to a close range under a certain condition and having an effective close warning display function. It is an object.

[0007]

A camera according to the present invention is a camera for measuring a subject distance at a plurality of points in a photographing image frame, and a center for measuring a distance to a subject in a central portion of the photographing image frame. Distance measuring means, peripheral distance measuring means for measuring the distance to the object in the periphery of the central portion, and the distance measurement result of the central distance measuring means is closer than a predetermined first distance. First determining means for determining whether or not the distance measurement result of the peripheral distance measuring means is shorter than a second distance determined in advance, and the first determining means The control means controls the amount of extension of the photographing lens based on the determination result of the determination means and the second determination means, and when the first determination means determines that the distance is shorter than the first distance. Based on the signal from the central distance measuring means, It is characterized by controlling the feeding amount of the lens.

Further, the present invention is characterized in that a warning means is provided for displaying a warning according to the judgment results of the first judging means and the second judging means.

[0009]

The distance measuring results of the central portion and the peripheral portion are judged by the first judging means and the second judging means, and when the judgment result of the first judging means is closer than the first distance, the control means is When the distance measurement result of the partial distance measuring unit is closer than the first distance, the amount of extension of the photographing lens is controlled based on the signal from the central distance measuring unit.

When the determination result of at least one of the first determining means and the second determining means is a shorter distance than the first and second distances, a warning display is given by the warning means. ..

[0011]

1 is a block diagram showing an embodiment of a multi-point distance measuring device for a camera according to the present invention.

In FIG. 1, the output portion of the central distance measuring circuit 101 is directly connected to the first input portion of the photographing lens feeding control circuit 105, and the photographing lens feeding control circuit 105 of the photographing lens feeding control circuit 105 is connected via the central portion distance determining circuit 103. It is connected to the second input section. The output section of the central distance determination circuit 103 is connected to the first input section of the warning display control circuit 108. The output part of the left peripheral distance measuring circuit 102a is directly connected to the third input part of the taking lens extension control circuit 105, and is also connected to the fourth input part of the taking lens extension control circuit 105 via the left peripheral part distance determination circuit 104a. It is connected. The output part of the left peripheral distance determining circuit 104 a is connected to the second input part of the warning display control circuit 108. The output portion of the right peripheral distance measuring circuit 102b is directly connected to the fifth input portion of the photographing lens extension control circuit 105, and is also connected to the sixth input portion of the photographing lens extension control circuit 105 through the right peripheral distance determination circuit 104b. It is connected. The output part of the right peripheral distance determining circuit 104b is connected to the third input part of the warning display control circuit 108.
The output part of the taking lens extension control circuit 105 is connected to the taking lens 107 via the taking lens drive circuit 106. The output portion of the warning display control circuit 108 is the display circuit 1
09 is connected.

Here, the central distance measuring circuit 101 constitutes the central distance measuring means, the central distance determining circuit 103 constitutes the first determining means, and the left peripheral distance measuring circuit 102a and the right peripheral distance measuring circuit. The circuit 102b constitutes a peripheral distance measuring unit, and includes a left peripheral distance determining circuit 104a and a right peripheral distance determining circuit 104.
Reference numeral b represents a second determination means, the photographing lens extension control circuit 105 and the photographing lens drive circuit 106 constitute a control means, and the warning display control circuit 108 and the display circuit 109 constitute a warning means.

FIGS. 2 and 3 are flowcharts showing an algorithm for distance measurement used to control the extension of the taking lens 107.

The operation of this embodiment will be described below with reference to FIGS.

First, the flags showing various states are cleared (S ₁ and S _{2 in} FIG. ₂ ). Next, the central distance measuring circuit 101 measures the distance in the central portion of the photographing image frame, and the central distance measuring result L
_{Get C} (S ₃ ). The central distance measurement result L _{C is set} to L _D (S ₄ ). When the value of the central distance measurement result L _C is farther than the predetermined value L _CKIN as the first distance, FIG.
Proceed to S ₉ (S ₅ ). Here, the predetermined value L _CKIN is a limit distance at which the camera is completely focused. If the value of the central distance measurement result L _C is closer than the predetermined value L _CKIN , AF
Make a END flag, that is writing a "1" (S _6).
Further, when the center distance measurement result L _C is a distance _longer than the predetermined value L _CGEN as the first distance, the process proceeds to S ₉ (S ₇ ). Here, the predetermined value L _CGEN is a limit distance at which the focus of the camera is substantially in focus. When the center distance measurement result L _C is _closer than the predetermined value L _CGEN , the closest flag is set, that is, “1” is written and the process proceeds to S ₉ (S ₈ ).

If the spot AF mode is set by the spot AF (AUTO FOCUS) mode setting circuit (not shown), the central area distance measurement result L _C is set as the focusing distance, and the determination is finished (S ₉ ). .. In the case of the normal shooting mode other than the spot AF mode, the process proceeds to S ₁₀ .

Next, performs ranging the left peripheral portion of the photographing frame by the left periphery distance measuring circuit 102a (L ranging), the process proceeds to S ₁₁ to obtain the L distance measurement result L _L (S ₁₀₎ .. For AFEND flag = 1, the process proceeds to S ₁₄ (S _11). If the AFEND flag is not 1, the left peripheral distance determining circuit 104a compares the values of the central distance measuring result L _C and the L distance measuring result L _L , and when the L distance measuring result L _L is a short distance. Sets L distance measurement result L _L to L _D (S ₁₂ , S ₁₃ ).

Next, the distance measurement (R distance measurement) is performed on the right peripheral portion within the photographing image frame, the R distance measurement result L _R is obtained, and the process proceeds to S ₁₅ (S ₁₄ ). S ₁₀ through the same process as performed in S ₁₃ R
Done for distance measurement result (S ₁₄ to S _17). When the value of L _D is _closer than the predetermined value L _SGEN as the second distance, the closest flag is set (S ₁₈ , S ₁₉ ). Here, the predetermined value L _SGEN is a limit distance at which the camera is completely focused. The distance used for the shooting lens extension control becomes the value of L _D , the AFEND flag and the close-up flag are set and reset according to the value of L _D , and the determination processing routine ends. Shooting lens drive circuit 106
Drives the taking lens 107 in response to the value of L _D.
That is, the determination result of the central distance determination circuit 103 is L _CKIN
When the distance is shorter than the distance, the photographing lens drive circuit 106
Controls the extension of the taking lens 107 by an amount according to the output signal L _C of the central distance measuring circuit 101.

On the other hand, the warning display control circuit 108 drives the display circuit 109 in accordance with the contents of the AFEND flag and the closest flag set by the processing routine.
FIG. 4 shows an example in which LEDs are used in the display circuit 109 and various warning displays are performed by changing the blinking cycle.

5 to 8 are views showing the object position and the distance measurement result determined by the processing routine. Here, L _CKIN = _0.76m , L _CGEN = _0.56m , L _SGEN = _0.76m
It shows the result of determination as a predetermined value. White circles and black circles in the figure indicate the position of the subject, and the black circles indicate multi-A.
The subject selected as a result of F is shown. In addition, the close limit here is a limit distance for taking a photograph that is enduring to the viewing.

FIG. 5 shows the case where the AFEND flag = 0 and the closest flag = 0, and normal distance measurement is performed.

FIG. 6 shows the case where the AFEND flag = 1 and the closest flag = 0, and a warning is issued by the display circuit 109, and the extension of the taking lens 107 is controlled by the result of distance measurement by the center beam.

FIG. 7 shows a case where the AFEND flag = 1 and the closest flag = 1. A warning is issued by the display circuit 109, and the extension of the taking lens 107 is controlled by the result of distance measurement by the center beam.

FIG. 8 shows the case where the AFEND flag = 0 and the close-up flag = 1. A warning is issued by the display circuit 109 and the lens latch of the taking lens 107 is set to the close-up.

In the above-described embodiment, the case where the distances are measured at three points of the central portion, the left peripheral portion and the right peripheral portion has been described, but the same processing can be performed even if the distance measuring points are increased. ..

Although an example using LEDs as the display circuit has been shown, various display circuits such as a liquid crystal display panel can be used.

As described above, according to the present embodiment, it is possible to focus the main object, which is composed in the center, up to a close range without a shooting error, and to provide a camera with an effective short range warning display function. It is possible to provide.

[0029]

According to the camera of the present invention, the control means is
When the distance measurement result of the central distance measuring means is closer than the first distance, the amount of extension of the photographing lens is controlled based on the signal from the central distance measuring means. , It is possible to shoot the main subject, which is composed in the center, according to the intention up to a close range.

Further, by providing the warning means for displaying the warning according to the judgment results of the first judging means and the second judging means, it is possible to provide a camera having an effective short distance warning displaying function. is there.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the present invention.

FIG. 3 is a flowchart for explaining the operation of the present invention.

FIG. 4 is a diagram showing a relationship between a flag used in the present invention and a warning display.

FIG. 5 is a diagram showing a positional relationship of subjects for explaining the operation of the present invention.

FIG. 6 is a diagram showing a positional relationship of subjects for explaining the operation of the present invention.

FIG. 7 is a diagram showing a positional relationship of objects for explaining the operation of the present invention.

FIG. 8 is a diagram showing a positional relationship of subjects for explaining the operation of the present invention.

[Explanation of symbols]

 101 ... Central distance measuring circuit 102a ... Left peripheral distance measuring circuit 102b ... Right peripheral distance measuring circuit 103 ... Central distance measuring circuit 104a ... Left peripheral distance determining circuit 104b ..Right peripheral distance determination circuit 105 ... Shooting lens extension control circuit 106 ... Shooting lens drive circuit 107 ... Shooting lens 108 ... Warning display control circuit 109 ... Display circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Michio Kawai 934-13 Shikato, Yotsukaido-shi, Chiba Stock Company Seikosha Chiba Works (72) Inventor Kanji Ito 934-13 Shikado, Yotsukaido-shi Chiba Seikosha Chiba Works

Claims (2)

[Claims] 1. A camera for measuring a subject distance at a plurality of points in a photographing image frame, wherein a central distance measuring means for measuring a distance to a subject at a central portion in the photographing image frame, Peripheral distance measuring means for measuring the distance to the object in the periphery, and first determining means for determining whether or not the distance measuring result of the central distance measuring means is closer than a predetermined first distance. And a second determination means for determining whether or not the distance measurement result of the peripheral distance measurement means is closer than a predetermined second distance, and the determination results of the first determination means and the second determination means. And a control means for controlling the amount of extension of the photographic lens based on the above. The control means outputs a signal from the central distance measuring means when the first determining means determines that the distance is shorter than the first distance. The amount of extension of the photographing lens based on A camera characterized by. 2. The camera according to claim 1, further comprising a warning unit that displays a warning according to the determination results of the first determination unit and the second determination unit.