JPH05119385A - Focusing state display device - Google Patents

Abstract

PURPOSE:To surely know what position from infinity to closest limit which can be photographed by a photographing lens is a focusing position and the present position of the photographing lens as for a focusing state display device where a focusing state is displayed and which is provided in a camera where focus is detected by using transmitted light from the photographing lens. CONSTITUTION:This device is provided with a means 101 which detects a distance from the infinity to the closest limit which can be photographed by the photographing lens and generates a 1st signal corresponding to the detected distance, a focusing position detecting means 102 which generates a 2nd signal corresponding to the focusing position, a lens position detecting means 103 which generates a 3rd signal corresponding to the position of the photographing lens, a conversion means 104 which inputs the 1st, the 2nd and the 3rd signals and converts the distance, the focusing position and the position of the lens to the value of the same scale, and a display means 105 which displays the relative positional relation of the distance, the focusing position and the position of the lens based on output from the means 104.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focus adjustment state display device for displaying a focus adjustment state, which is provided in a camera for performing focus detection using transmitted light from a taking lens.

[0002]

2. Description of the Related Art Conventionally, as a focus adjustment status display device for displaying the focus adjustment status of a camera, an LED for focus adjustment is provided on the basis of a signal from the focus detection device when the taking lens is in focus. The one that lights up is widely adopted.

However, in such a focus adjustment state display device, when the taking lens is in focus, it can be recognized that it is in focus, but when it is not in focus, the amount of focus shift and the like are recognized. Can not do it.

To solve this problem, Japanese Patent Laid-Open No. 2-74934 discloses a focus adjustment state display device for displaying a focus shift amount when the subject is out of focus and providing the photographer with detailed information on the focus state. The one disclosed has been developed.

FIG. 10 shows a focus adjustment state display device disclosed in this publication. In this focus adjustment state display device, a display section for displaying the focus adjustment state on the side of the photographing screen 1002 of the finder 1001. 1003 is formed.

The display unit 1003 is provided with a light emitting unit 10 at the center.
04, the upper six light emitting units 1005, and the lower six
Two light emitting parts 1006 and light emitting parts 1007, 10 on both end sides
It is formed by 08.

When the defocus information indicates the front focus, the central light emitting unit 1004 is turned on, and further the upper light emitting unit 1005 is turned on according to the defocus amount, and when the defocus amount is large, The light emitting unit 1007 at the upper end is turned on.

On the other hand, when the defocus information indicates the focused state, the central light emitting portion 1004 is turned on. Further, when the defocus information indicates the rear focus, the central light emitting unit 1
004 is turned on, and further, the lower light emitting unit 1006 is turned on according to the defocus amount, and when the defocus amount is large, the lower light emitting unit 1008 is turned on.

[0009]

However, in such a conventional focus adjustment state display device, the light emitting section 100 is used.
Since the defocus amount is displayed by 5, 1006, the focus position and the current position of the photographing lens are
It is not possible to know where the shooting lens is from infinity to the close-up limit, especially if the subject is out of focus even when the subject is close to the close-up limit of the shooting lens. There was a problem that I could not know.

The present invention has been made in order to solve such a conventional problem, and which positions of the in-focus position and the current position of the photographing lens are from infinity to the close limit at which the photographing lens can photograph. An object of the present invention is to provide a focus adjustment state display device capable of surely knowing.

[0011]

FIG. 1 is a diagram showing a configuration of a focus adjustment state display device provided in a camera for performing focus detection using transmitted light from a photographing lens according to claim 1, and FIG. Reference numeral 101 is a unit for detecting a distance from the infinity to the closest limit that can be photographed by the photographing lens and generating a first signal corresponding to the distance.

Reference numeral 102 is a focus position detecting means for detecting the focus position of the photographing lens focused on the object and generating a second signal corresponding to the focus position. Reference numeral 103 is
It is a lens position detecting means for detecting a position where the photographing lens is present and generating a third signal corresponding to the position of the photographing lens.

Reference numeral 104 is a conversion means for inputting the first signal, the second signal, and the third signal, and converting the distance, the in-focus position, and the lens position into values of the same scale.
Reference numeral 105 is a display unit that displays the relative positional relationship between the distance, the in-focus position, and the lens position from the output of the conversion unit 104.

According to a second aspect of the present invention, in the focus adjustment state display device according to the first aspect, the conversion means 104 converts the distance, the in-focus position, and the lens position into a value on the same scale as a displacement amount from a specific reference position. To do.

According to a third aspect of the present invention, in the second aspect, the specific reference position is a position at infinity at which the photographing lens can photograph. According to a fourth aspect of the present invention, in the focus adjustment state display device according to the second aspect, the specific reference position is a position at a close limit at which the photographing lens can photograph.

According to a fifth aspect of the focus adjustment state display device of the first or second aspect, the conversion means 104 converts the distance, the in-focus position, and the lens position into the extension amount of the photographing lens.

According to a sixth aspect of the present invention, there is provided the focus adjustment state display device according to the first or second aspect, wherein the conversion means 104 converts the distance, the in-focus position, and the lens position into an image plane movement amount by the photographing lens. is there.

According to a seventh aspect of the present invention, in the fifth or sixth aspect, the in-focus position is converted as a displacement amount from the lens position.

[0019]

In the focus adjustment state display device according to the present invention, the means 101 for generating the first signal detects the distance from the infinity to the near limit which can be photographed by the photographing lens, and the first distance corresponding to the distance is detected. A signal is generated, the in-focus position detecting means 102 detects the in-focus position of the photographing lens in focus on the subject, a second signal corresponding to the in-focus position is generated, and the lens position is detected. The means 103 detects the position of the taking lens, generates a third signal corresponding to the position of the taking lens, and converts these first signal, second signal, and third signal into the converting means 104. The distance, focus position, and lens position are converted into values on the same scale by the conversion means 104, and then the output of the conversion means 104 is input to the display means 105, and the display means 1 is displayed.
By 05, the relative positional relationship between the distance, the in-focus position, and the lens position is displayed.

In the focus adjustment state display device according to the second aspect, the conversion means 104 converts the distance, the in-focus position, and the lens position into values on the same scale as the displacement amount from the specific reference position.

In the focus adjustment state display device of the third aspect, the specific reference position is a position at infinity at which an image can be taken by the taking lens. In the focus adjustment state display device according to the fourth aspect, the specific reference position is a position at a close limit at which the photographing lens can photograph.

In the focus adjustment state display device according to the fifth aspect, the conversion means 104 converts the distance, the in-focus position, and the lens position into the extension amount of the photographing lens. In the focus adjustment state display device according to the sixth aspect, the conversion unit 104 converts the distance, the focus position, and the lens position into the image plane movement amount by the photographing lens.

In the focus adjustment state display device of the seventh aspect, the in-focus position is converted as the amount of displacement from the lens position.

[0024]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 2 shows a camera provided with an embodiment of the focus adjustment state display device of the present invention.
The subject light that has passed through the taking lens 201 is reflected by the main mirror 2.
At 02, the light is split into the finder 203 side and the sub-mirror 204 side, and the light to the sub-mirror 204 side is reflected by the sub-mirror 2
At 04, the optical path is further bent and the light is guided to the distance measuring unit 205.

On the other hand, the light guided to the finder 203 side by the main mirror 202 is the finder screen 20.
A subject image is formed at 6, is bent by a pentaprism 207, and is then guided to an eyepiece lens 208.

Lens part 2 in which photographing lens 201 is arranged
The ROM 210 stores lens data,
A lens data storage unit 220 that stores the focal length and the F number of the photographing lens 201, and an encoder 211 that reads the extended position of the photographing lens 201 in conjunction with the movement of the photographing lens 201 are arranged.

The camera body 212 includes a taking lens 20.
The distance measuring unit 205 described above that detects a focus adjustment state by capturing a part of the light flux from the first light measuring unit 205 is disposed.
Detects the defocus amount by a known method, for example, a phase difference method.

Reference numeral 213 is a CPU.
213 converts the defocus amount obtained from the distance measuring unit 205 into a lens driving amount based on the lens data of the ROM 210 described above.

Reference numeral 214 is a control unit, and this control unit 214 controls a motor 215 for driving the taking lens 201 based on the lens drive amount obtained by the CPU 213.

Reference numeral 216 is a display unit, and this display unit 216 displays the focus adjustment state as described later. Reference numeral 217 is an AE device, which has a condenser lens 218 and a photometric element 219.

FIG. 3 shows a photographing screen 3 of the finder 301.
02, in this embodiment, a display unit 216 for displaying the focus adjustment state is formed on the upper side of the photographing screen 302.

The display section 216, as shown in FIG.
A light emitting unit 401 indicating the infinity position ∞ of the taking lens 201 is formed at the left end, and a light emitting unit 402 indicating the close-up limit position N of the taking lens 201 is formed at the right end spaced from the light emitting unit 401 by a predetermined distance. There is.

Between the left and right light emitting portions 401 and 402,
For example, a large number of dots 403 composed of light emitting diodes
However, they are arranged linearly adjacent to each other. FIG. 5 shows the display contents when the focus adjustment state is in the rear focus state.
At this time, the dot 403 at the lens position A, the dot 403 at the focus position B, and the dot 403 between the lens position A and the focus position B are turned on, and the lens position A and the focus position B are photographed. The position at which the lens 201 can photograph from infinity to the near limit is displayed.

The amount of focus shift at this time is indicated by the interval of the dots 403. In this embodiment, the distance between the infinity position ∞ and the close limit position N of the display unit 216 is
Since the scale is set to correspond to the amount of image plane movement between the infinity position ∞ and the close limit position N on the film surface, the lens position A and the focus position B are set to the infinity position ∞ or the close position, respectively. It is displayed as the amount of movement of the image plane on the film surface from the limit position N.

As a result, the distance between the lens position A and the in-focus position B indicates the defocus amount Df. Next, how to obtain the lens position A and the focus position B will be described.

First, the closest limit position N is obtained from the lens data of the ROM 210. This is because when the lens data stores the amount of image plane movement from the infinity position ∞ to the closest limit position N as data, the amount of data from the infinity position ∞ to the closest limit position N is used as is. It should be done.

Further, when the closest limit position N is stored in the lens data as an absolute distance, for example, 1 m, the image plane movement amount from the infinity position ∞ to the closest limit position N is calculated from the lens formula. Just do it.

That is, as shown in FIG. 6, if the focal length f of the taking lens 201 is given, the relationship between the subject distance R from the subject to the image plane and the lens extension amount x'is given by the following equation. ..

X ′ = f ² / (R−2f) In FIG. 6, the amount of extension of the taking lens 201 between the infinity position ∞ and the near limit position N is calculated as x ′ when R = ∞, It suffices to find x ′ when R = N and find the difference between them.

On the other hand, the closest limit distance (eg, 1 m) stored in the lens data is entered in R of the above equation, and the focal length f is substituted from the lens data to obtain the closest limit distance x '. ..

It should be noted that x'at the infinity position ∞ becomes 0 from R = ∞, and the lens extension amount x '(∞ to N) between the infinity position ∞ and the close limit position N is the close limit distance. It corresponds to the amount of feeding x ′.

Next, the current lens position A is read by the encoder 211 as an absolute distance, for example, 5 m. As a result, the reading distance from the encoder is substituted into R in the above equation to obtain x '(∞ to A), similarly to the above-mentioned amount of extension x' (∞ to N) up to the closest limit distance.

When the current lens position x '(∞ to A) is obtained, the lens position A is displayed as shown in FIG. Since the focus position B is calculated as the defocus amount Df by the distance measuring unit 205, for example, when the calculation result finds that the focus surface is 2.5 mm behind the film surface, the focus position B is calculated from the lens position A. The in-focus position B is displayed at a position of 2.5 mm in the closest limit position N direction.

The dot 403 at the in-focus position B is displayed in, for example, a green or blue tone, and the lens position A
It is desirable that the continuous dots 403 indicating "." Be displayed in a yellow color tone, but it is necessary to select a color tone that makes the distinction between the dots 403 at the focus position B and the lens position A clear.

The dots 403 at the focus position B may be displayed by two or three dots 403 when one dot 403 is fine. Further, the light emitting portions 401 and 402 for the infinity position ∞ and the near limit position N are displayed in a color different from the focus position B and the lens position A display dot 403.

FIG. 7 is a flow chart showing the operation of the focus adjustment state display device of this embodiment. First, in step 701, when the release button of the camera is half pressed,
In step 702, the flag n = 0 is set.

Next, in step 703, the distance measuring unit 2
The distance measurement by 05 is performed and the defocus amount is detected.
In step 704, lens data and absolute distance signals are read.

Next, in step 705, it is determined whether or not the in-focus position B can be calculated. For example, when it is determined that the subject is dark or has no contrast, the process proceeds to step 707 and the display unit 216. A message indicating that distance measurement is impossible is displayed.

This indication that distance measurement is impossible is performed by simply turning on the dot 403 at the lens position A, as shown in FIG. 8 (e). If the focus position B can be calculated,
In step 706, it is determined whether the camera is set to the AF mode or the focus aid mode (manual focus mode).

When the AF mode is set, the routine proceeds to step 708, where it is determined whether or not the distance measurement limit is exceeded, that is, whether the in-focus position B is outside the lens drive range that exceeds the closest limit position N. To be judged.

When it is over, step 709
Then, the display unit 216 displays that the focus position is outside the lens drive range. This distance measuring limit display is, as shown in FIG. 8D, the light emitting unit 40 indicating the closest limit position N.
This is done by blinking 2 to inform the photographer that focusing is impossible.

When it is not over, step 71
0, and as described above, the amount of extension x ′ (∞ to ∞ between the infinity position ∞ and the close limit position N of the taking lens 201.
N), the current amount of extension of the taking lens 201 x '(∞ ~
A), the defocus amount Df is calculated, and these are converted into values on the same predetermined scale.

Next, in step 711, the display unit 21
At 6, the infinity position ∞, the near limit position N, the lens position A, and the focus position B are displayed. This display is shown in FIG.
Alternatively, it is performed as shown in (b).

Incidentally, (a) is in the rear pin state,
(B) is the state of the front pin state. Next, step 712.
At, the focus adjustment state is determined. That is, when the lens position A-focus position B ≠ 0 is not satisfied, the focus state is in effect, so the flow advances to step 716 to display the focus state.

This display is, as shown in FIG.
This is performed by turning on the dot 403 at the focus position B, and the display dot 403 at the lens position A is not turned on. On the other hand, when it is out of focus, the process proceeds to step 713, and when the flag n = 0, the process proceeds to step 714.

When the flag n = 0 is not satisfied, the lens drive is locked in the single AF mode (S-AF), that is, when the focus is achieved, and thereafter, the photographing lens 201 is moved even if the defocus amount occurs. In the non-mode, it means that the lens drive is locked once the focus is achieved.

When the flag n = 0, it means that the lens drive is not locked. At this time, step 7
At 14, it is determined whether or not the AF is locked, that is, whether or not the photographer intentionally stops the lens driving. If the AF is not locked, the lens driving is executed at step 715.

On the other hand, in step 713, S-AF
Then, if the focus is once and the lens drive is locked, or if the lens drive is locked by the photographer in step 714, the process goes beyond step 715 to step 716 to display the focus state. Be seen.

In step 717, it is determined whether or not it is S-AF, and when it is S-AF, the flag n = 1 is set in step 718. In step 719, it is determined whether or not the release button is fully pressed, and when it is not pressed, it is determined in step 720 whether or not the release button is half pressed, and when it is not half pressed, the flow ends. On the other hand, when the button is half pressed, the process returns to step 703 and the flow is repeated.

In step 706, it is determined that the AF mode is not set, and after displaying in step 725, or after displaying in step 707 or step 709, jump to step 719.

In step 719, when the release button is fully pressed, the process proceeds to step 722 to perform exposure, in step 723 the flag n = 0 is reset, and in step 724 the release button is half pressed. It is determined whether or not there is a half-press, and if it is half-press, the process returns to step 703, and if it is not half-press, the flow is ended.

FIG. 10 shows a display when the taking lens 201 not provided with the absolute distance signal is mounted, and at this time, the light emitting portions 401 and 402 at the infinity position ∞ and the near limit position N at both ends. Is turned off. Further, at this time, since the lens position A is not obtained, the focus position B
Is fixedly displayed in the center of the display unit 216, and the defocus amount calculated based on the distance measurement is displayed on the left and right of the in-focus position B according to the directions of the front focus and the rear focus. In addition,
The display direction of the defocus amount at this time is preferably the same direction as a and b in FIG. That is, FIG. 9 or 10 is in the front pinned state. In the focused state, only the dot 403 for displaying the focused position B is displayed.

In the focus adjustment state display device configured as described above, the light emitting unit 401 displays the infinity position ∞, the light emitting unit 402 displays the closest limit position N, and further the focusing position B and the current position. Since the position A of the taking lens 201 is displayed by the dot 403, the focus position B
Also, it becomes possible to easily know with certainty where the current position B of the taking lens 201 is from the infinity to the close limit at which the taking lens 201 can take an image.

Therefore, it becomes possible for the photographer to accurately judge the current focus condition during photographing. Also,
When the subject is on the close side beyond the close limit of the taking lens 201, it can be easily known that focusing cannot be performed, so that it is possible to prevent a shooting failure.

Further, at the time of focus aid or power focus, the photographing lens 201 by the photographer
Is very easy to operate. Further, in a camera equipped with a lens limiter that limits the operating range of the taking lens 201, the setting position of the lens limiter is displayed on the display unit 21.
By displaying in 6, it becomes possible to easily determine whether or not the in-focus position B is beyond the lens limiter.

In the embodiment described above, the display unit 21
Although the example in which 6 is formed by the light emitting element has been described, the present invention is not limited to such an example, and it may be formed by a display element such as a liquid crystal and displayed on the finder screen. Of course.

In the embodiment described above, the infinity position ∞ and the near limit position N are fixed, and the in-focus position B and the lens position A are displayed on the scale corresponding to the interval between them. However, the present invention is not limited to such an embodiment, and according to the distance between the infinity position ∞ and the close limit position N of the taking lens 201,
The distance between the infinity position ∞ and the near limit position N is variably configured, and the focus position B is adjusted on the scale corresponding to the distance between them.
Of course, the lens position A may be displayed.

Further, in the above-described embodiments, an example in which the lens position A and the focus position B are defined from the infinity position at which the photographing lens 201 can be photographed as a specific reference position has been described. The invention is not limited to such an embodiment, and the lens position A and the focus position B may be defined from this position with the closest reference position where the image pickup lens 201 can be used as a specific reference position. Of course.

[0069]

As described above, in the focus adjustment state display device according to the first aspect, the relative positional relationship among the distance between the infinity and the near limit, the focus position, and the lens position A is displayed by the display means. Since the display is made, it becomes possible to surely know where the in-focus position and the current position of the taking lens are from the infinity at which the taking lens can take an image to the close limit.

In the focus adjustment state display device according to the second aspect, the distance, the focus position, and the lens position are converted into values on the same scale as the displacement amount from the specific reference position by the conversion means, so that the current lens state is obtained. Can be displayed very easily.

In the focus adjustment state display device according to the third or fourth aspect, the specific reference position is set to the position at infinity or the position at the close range where the image can be taken by the taking lens, so that the calculation becomes easy.

In the focus adjustment state display device of the fifth or sixth aspect, the distance between infinity and the near limit, the focus position, and the lens position are converted into the moving amount of the photographing lens or the moving amount of the image plane. Calculation becomes easy.

In the focus adjustment state display device of the seventh aspect, the in-focus position is converted as a displacement amount from the lens position, so that there is an advantage that the calculation becomes easy.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a focus adjustment state display device of the present invention.

FIG. 2 is an explanatory diagram showing a camera provided with an embodiment of a focus adjustment state display device of the present invention.

FIG. 3 is an explanatory diagram showing a shooting screen and a display unit of the finder.

FIG. 4 is an explanatory diagram showing details of a display unit.

FIG. 5 is an explanatory diagram showing a display unit in a rear-pinned state.

FIG. 6 is an explanatory diagram showing a method of calculating a distance between infinity and a near limit, a focusing position, and a lens position.

FIG. 7 is a flowchart showing the operation of the focus adjustment state display device of FIG.

FIG. 8 is an explanatory diagram showing a display mode of a display unit.

FIG. 9 is an explanatory diagram showing a display state of a display unit when there is no encoder.

FIG. 10 is an explanatory diagram showing a display unit of a conventional focus adjustment state display device.

[Explanation of symbols]

 101 means for generating a first signal 102 in-focus position detection means 103 lens position detection means 104 conversion means 105 display means 201 photographic lens A lens position B in-focus position ∞ infinity position N near limit position

Claims (7)

[Claims] 1. A focus adjustment state display device provided in a camera for performing focus detection using transmitted light from a photographing lens, wherein a distance from infinity to a close limit at which the photographing lens can photograph is detected, and the distance is set to the distance. A means for generating a corresponding first signal, a focus position detecting means for detecting a focus position of the photographing lens focused on the subject and generating a second signal corresponding to the focus position, and a photographing lens A lens position detecting means for detecting a position where the lens exists and generating a third signal corresponding to the position of the photographing lens; and inputting the first signal, the second signal, and the third signal,
Conversion means for converting the distance, in-focus position, and lens position into values of the same scale; and display means for displaying the relative positional relationship between the distance, in-focus position, and lens position from the output of the conversion means, A focus adjustment state display device comprising: 2. The focus adjustment state display according to claim 1, wherein the conversion means converts the distance, the in-focus position, and the lens position into values on the same scale as the displacement amount from the specific reference position. apparatus. 3. The focus adjustment state display device according to claim 2, wherein the specific reference position is a position at infinity at which the photographing lens can photograph. 4. The focus adjustment state display device according to claim 2, wherein the specific reference position is a position at a near limit at which the photographing lens can photograph. 5. The conversion means is configured to detect the distance, the in-focus position,
The focus adjustment state display device according to claim 1, wherein the lens position is converted into the amount of extension of the taking lens. 6. The converting means comprises: the distance, the in-focus position,
The focus adjustment state display device according to claim 1 or 2, wherein the lens position is converted into an image plane movement amount by the taking lens. 7. The focus adjustment state display device according to claim 5, wherein the focus position is converted as a displacement amount from the lens position.