JP2002023041A - Photographing distance measuring device, photographing lens, camera system and information arithmetic device for camera system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect a photographing distance without moving a distance ring to a specified initial position even in a photographing lens where photographing distance information is not outputted. SOLUTION: This camera system is provided with position detection means 1 and 4 detecting the extending position of the photographing lens, optical information output means 1 and 5 outputting sensitivity or a best focus correction value in accordance with the extending position detected by the detection means as optical information and an arithmetic means 8 calculating the photographing distance according to the optical information from the optical information output means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a photographing distance measuring device for outputting photographing distance information, a photographing lens, a camera system, and an information processing device for the camera system.

[0002]

2. Description of the Related Art In an optical apparatus such as a camera, it is useful to obtain a distance from a film surface to a subject, that is, a shooting distance. For example, a number of automatic flash light control devices using this shooting distance have been proposed so far. Also,
The distance obtained by subtracting the focal length from the shooting distance is substantially equal to the subject distance which is the distance from the front principal point of the lens to the subject. In servo photography in which a photographing lens follows a moving subject, a method of performing highly accurate moving object prediction based on the subject distance has also been disclosed by the present applicant in Japanese Patent Laid-Open No. 11-197.
No. 185.

[0003]

Conventionally, in measuring the photographing distance, the distance ring of the photographing lens is electrically divided into equal intervals of about 4 to 32, and the approximate distance is determined by detecting the extension position of the photographing lens. In general, a photographing distance was obtained. In this method, the more the number of divisions of the distance ring of the photographing lens is increased, the more accurate the photographing distance information can be obtained. However, the extension position detection device and the signal transmission device become complicated, and the cost increases. There is a problem that.

Generally, in the case of an inner focus photographing lens, optical information such as sensitivity changes in accordance with the extension position of the photographing lens and, in the case of a zoom lens, the focal length. Therefore, the extension position and the focal length of the photographing lens are detected, and optical information corresponding to the detected position is output. However, many of the early interchangeable lenses and inexpensive interchangeable lenses of interchangeable lens cameras do not output the shooting distance information for simplicity.

In Japanese Patent Publication No. Hei 6-17930, when a photographing lens is mounted, a distance ring is temporarily moved to an infinity position and stored as an initial position, and photographing is performed based on an extension amount of the photographing lens from the initial position. A method for measuring distance is disclosed. This method guarantees that the camera-side mechanism alone can obtain the shooting distance information with a certain degree of accuracy, even if there is no output of the shooting distance information on the lens side. Equipped camera,
Each time the focus is switched from manual to auto focus, the distance ring is moved to infinity,
There is a possibility that a decisive moment may be missed in super telephoto shooting with a large amount of extension or portrait shooting in which manual and auto focus are frequently switched.

(Object of the Invention) An object of the present invention is to provide a distance ring for a photographing lens for which photographing distance information has not been output, or for a photographing lens having a small number of distance ring divisions and low detection accuracy even if outputted. An object of the present invention is to provide a photographing distance measuring device, a photographing lens, a camera system, and an information processing device for a camera system that can detect a photographing distance with high accuracy without moving to a predetermined initial position.

[0007]

In order to achieve the above object, according to the present invention, there is provided a position detecting means for detecting an extended position of a photographing lens, and an extended position detected by the position detecting means. The optical information output means outputs the sensitivity or the best focus correction value according to the above as optical information, and the calculating means calculates the photographing distance from the optical information from the optical information output means.

[0008] In the above configuration, even if the photographing distance information is not output from a photographing lens having a fixed focal length, the photographing distance is calculated from the output of the optical information.

According to another aspect of the present invention, there is provided an image forming apparatus comprising: a position detecting means for detecting a feeding position of a photographing lens; a focal length detecting means for detecting a focal length of the photographing lens; Optical information output means for outputting, as optical information, a sensitivity or a best focus correction value according to the extension position detected by the detection means and the focal length detected by the focal length detection means; and the optical information output means Computing means for calculating the photographing distance from the optical information from the camera.

[0010] In the above configuration, the photographing distance measuring apparatus calculates the photographing distance from the output of the optical information even when the photographing distance information is not output from the photographing lens having a variable focal length.

According to another aspect of the present invention, a first position detecting means for detecting an extended position of a photographing lens, and an extended position detected by the first position detecting means. Calculating means for calculating a photographing distance from a position; second position detecting means for detecting a position of the photographing lens after a change in the extension position is detected by the first position detecting means; and the first position Correction means for correcting the photographing distance in accordance with a change in the lens position from the reference position based on the lens position detected by the second position detection means when the extension position of the detection means has changed; and And a photographing distance information output means for outputting the corrected photographing distance.

In the above configuration, the photographing lens outputs highly accurate photographing distance information from the change in the extending position and the lens position even if the detection accuracy of the extending position of the photographing lens is poor.

According to another aspect of the present invention, there is provided a camera system having the photographing distance measuring apparatus according to any one of the first to fourth aspects.

According to another aspect of the present invention, there is provided a lens device which has a storage unit for storing correction data in accordance with an extension position of a photographic lens, and which transmits the correction data to a camera. A camera system configured with a camera, comprising a storage unit for storing data corresponding to a shooting distance in the camera, and stored in the storage unit in accordance with the correction data transmitted from the lens device. This is a camera system for selecting data.

According to another aspect of the present invention, there is provided an image processing apparatus, comprising: a data corresponding to a photographing distance set corresponding to each of a plurality of moving regions of a photographing lens; Based on the switching position of the area as a reference position, based on the displacement amount detected by the displacement amount detecting means for detecting the displacement amount from the reference position in the area of the taking lens, data corresponding to the shooting distance is obtained. This is an information calculation device for a camera system having calculation means for calculating.

In order to achieve the above object, the invention according to claim 19 stores data corresponding to a photographing distance set corresponding to each of the plurality of divided moving regions of the photographing lens. The camera includes a camera having storage means, and a photographing lens device having displacement amount detecting means for detecting a displacement amount from a reference position in a region of the photographing lens using the switching position of the moving area as a reference position. In the camera system, there is provided a calculating means for calculating data corresponding to a photographing distance based on the displacement amount detected by the displacement amount detecting means and the data in the area where the photographing lens is stored stored in the storage means. This is a camera system.

According to another aspect of the present invention, in accordance with the present invention, data corresponding to a photographing distance set corresponding to each of the plurality of moving regions of the photographing lens, Using the switching position of the movement area as a reference position, the focal length and the displacement amount detected by the displacement amount detection means for detecting the displacement amount from the reference position in the area of the photographing lens correspond to the photographing distance. This is an information calculation device for a camera system having calculation means for calculating data to be processed.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

(First Embodiment) FIG. 1 is a block diagram showing a configuration of an interchangeable lens type single-lens reflex camera which is an example of an optical apparatus according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a lens MPU (micro processing unit) for performing all calculations and controls related to the photographing lens, 2 denotes a lens driving unit for driving the photographing lens, 3 denotes a lens position detecting unit, and 4 denotes a lens position detecting unit. The extension position detection unit 5 is an optical information table that differs for each interchangeable lens, such as the sensitivity described below, the lens extension amount per pulse, and the best focus correction value. The photographic lens according to the first embodiment is a fixed focal length lens having a fixed focal length. Also, an actual photographing lens requires an aperture drive unit for driving the aperture, but the description is omitted because it is not relevant in the present embodiment.

A photographic lens is constructed by using the lens MPU 1 to the optical information table 5 as main components, and the photographic lens is connected to the camera body via a mount indicated by a dotted line in the center of FIG.

Reference numeral 8 denotes a camera MPU (micro processing unit) that performs all calculations and controls related to the camera body.
The lens MPU 1 is connected to the lens MPU 1 via a signal line of the mount, and can drive the lens MPU 1 and acquire optical information unique to each interchangeable lens. 9
Is a defocus amount detection unit, 10 is a shutter drive unit, 11 is a film feeding unit, 12 is a dial unit for performing various settings (shutter speed, aperture value, shooting mode, etc.) of the camera, and 13 is a shooting distance conversion table It is. SW1 is a switch that is turned on by the first stroke operation (half press) of the release button, and SW2 is a switch that is turned on by the second stroke operation (full press) of the release button.

In the first embodiment, the switch SW
When the switch 1 is turned on, automatic focus adjustment is performed, and when the switch SW2 is turned on, a release operation is performed. Various shooting modes can be set by operating the dial unit 12. The operation when servo shooting is set as the shooting mode by the dial unit 12 will be described with reference to the flowchart of FIG.

When the switch SW1 is turned on, servo photographing starts at step # 101. And Step # 1
At 02, the ID of the taking lens is obtained. The lens ID is assigned a unique value for each interchangeable lens, and can be obtained by communicating with the lens MPU1.

The defocus amount (difference between the image forming position of the photographing lens and the image plane position of the photographing lens for performing the photographing operation) required for the automatic focusing is determined by two different regions sandwiching the optical axis of the photographing lens. It is calculated from the image shift amount (prediction amount) of two images formed from the passing subject light flux.
Specifically, the luminous flux of these two images passes through a main mirror which is a half mirror, is reflected by a sub-mirror located behind the half mirror, and is guided to a defocus amount detection unit 9 by a focus detection optical system (not shown). The defocus amount detection unit 9 is a photoelectric conversion element, and the camera MPU 8 reads out the signals of these two images in step # 103 and performs a correlation operation in the next step # 104 to determine the image shift amount. Calculate and find the defocus amount.

The defocus amount is obtained in this manner. There is a relation of 1 = d / S between the defocus amount d (mm) and the actual extension amount l (mm) of the photographing lens. , S are called sensitivity. As is well known, in a currently mainstream inner focus photographing lens, the sensitivity varies depending on the photographing lens and the extension position of the photographing lens. Although the actual sensitivity S is a function corresponding to the defocus amount d, in the present embodiment, it is a constant for simplicity of description. Also, the amount handled in the actual feeding is not l itself, but the number of focus pulses P (p
ulse) is expressed as follows.

P = l / h = d / h / S where h (mm / pulse) is the lens extension amount per pulse. Therefore, when the calculation of the defocus amount d is completed in step # 104, the camera MPU 8 proceeds to step # 105, and obtains h and S by communicating with the lens MPU1. Specifically, the distance ring of the photographing lens is electrically divided into regions at equal intervals (for example, about 4 to 32), and connected to the extended position detection unit 4. The lens MPU 1 acquires the current extension position from the extension position detection unit 4, determines the sensitivity S by referring to the optical information table 5, and transmits this to the camera MPU 8. Further, h is always constant irrespective of the feeding position, and is transmitted to the camera MPU 8. Upon receiving these optical information, the camera MPU 8 converts the information into the number of focus pulses P in the next step # 106.

The lens drive amount required for focusing is obtained in this manner. In a single-lens reflex camera, even when the switch SW2 is turned on, the release time lag in which the exposure does not start until the mirror-up or the aperture stop of the photographing lens ends is completed. There is. When shooting moving subjects such as motor sports, it is common to use a super-telephoto lens with a shallow depth of field.Therefore, it is necessary to drive the lens in anticipation of this release time lag and focus accurately at the time of exposure There is. Therefore, in the following step # 107, the photographing distance is measured, and based on the measurement result, in the next step # 108, a moving object is predicted, and the number of focus pulses P
Is corrected. As described above, the correction of the feeding amount based on the moving object prediction is described in Japanese Patent Application Laid-Open No. H11-197185.
And are not directly related to the present invention, so that the description is omitted.

When the final number of focus pulses is determined in step # 108, the camera MPU 8 communicates with the lens MPU 1 to cause the lens MPU 1 to drive the lens in the next step # 109. Lens MPU1
Is to optically count the lens movable portion by an encoder and a counter portion in the lens position detection unit 3 and stop driving when the displacement amount of the lens position matches the number of focus pulses.

The encoder forms one pulse each time the lens movable section moves by a unit length, and counts this pulse in the counter section. Here, the unit length is set so that the movement amount in the divided area can be finely discriminated as a count value.

Thereafter, the process proceeds to step # 110, where it is determined whether or not the switch SW1 is turned on. If the switch SW1 is turned on, the process proceeds to step # 111.
Proceeding to 113, the servo photography ends.

Steps # 110 to # 11
When the process proceeds to step 1, it is determined whether the switch SW2 is turned on. If the switch SW2 is turned on, the process proceeds to the step # 103 via the release operation of the step # 112. Otherwise, the process directly proceeds to the step # 103. The servo servo processing is repeated.

Next, the routine for measuring the photographing distance called in step # 107 will be described with reference to the flowchart of FIG.

When the photographing distance measurement routine is called in step # 201, the process proceeds to step # 202, in which the photographing distance conversion table 13 is searched. Specifically, FIG.
The camera MPU 8 refers to the shooting distance conversion table 13 based on the lens ID acquired in step # 102. A plurality of tables are provided for each ID.

The photographing lens of the first embodiment is a single focus lens, and the photographing distance conversion table corresponding to the lens ID is as shown in FIG. As described above, the sensitivity of the photographic lens having the inner focus changes depending on the extension position of the lens. Therefore, camera MPU8
Retrieves a table based on the sensitivity S acquired in step # 105 of FIG. 5. If, for example, the current sensitivity is "0.120", the photographing lens is at the extended position "2" and the photographing distance is "10.20". 5.5.20 m ”.

In the first embodiment, the photographing distance is calculated based on the sensitivity. However, if the optical information changes in accordance with the extension position of the photographing lens, such as the best focus correction value, the same is true. It can be implemented in

According to the first embodiment, attention is paid to the fact that the optical information such as the sensitivity and the best focus correction value changes according to the extension position of the photographing lens, and from the output of the optical information to the photographing distance. Is calculated, it is possible to detect an accurate shooting distance without moving the distance ring to a predetermined initial position even in a shooting lens for which shooting distance information is not output.

(Second Embodiment) FIG. 2 is a block diagram showing the structure of an interchangeable lens type single-lens reflex camera which is an example of an optical apparatus according to a second embodiment of the present invention. Although it is almost the same as the block diagram of the first embodiment (FIG. 1), the photographing lens in the second embodiment is a zoom lens having a variable focal length, and focus detection for detecting the current focal length. The difference is that a unit 6 is added. The photographing lens is configured with the main components from the lens MPU 1 to the focus detection unit 6.

The operation of the camera is the same as that of the flowchart of FIG. 5 described in the first embodiment, except that the photographing distance in step # 202 in the photographing distance measurement routine called in step # 107 of FIG. Conversion table 1
Only the search processing of No. 3 is different. Specifically, based on the lens ID acquired in step # 102 of FIG.
U8 refers to the shooting distance conversion table 13. The photographing lens of the second embodiment is a zoom lens, and the photographing distance conversion table corresponding to the lens ID is as shown in FIG.

First, the camera MPU 8 obtains the focal length f (mm) by communicating with the lens MPU 1. Similarly to the sensitivity, the lens MPU 1 detects the current focal length from the focal length detecting unit 6 and transmits the current focal length to the camera MPU 8. The camera MPU 8 searches the shooting distance conversion table 13 based on the focal length and the sensitivity S acquired in step # 105 in FIG. 5, and if the current focal length is, for example, "f = 200"
(Mm) "and the sensitivity is" 0.154 ", the photographing lens is at the extended position" 2 ", and the photographing distance is" 10.20 to
5.20 m ”.

In the second embodiment, the photographing distance is calculated based on the sensitivity. However, if the optical information changes according to the extension position of the photographing lens, such as the best focus correction value, the same is true. It can be implemented in

According to the second embodiment, in a photographing lens provided with a zoom lens capable of changing the focal length, the sensitivity and the best focus correction value depend on the extension position and the focal length of the photographing lens. Focusing on the fact that the optical information changes, the photographing distance is calculated from the optical information. Therefore, even in a photographing lens in which the photographing distance information is not output, the accuracy of the precision can be improved without moving the distance ring to a predetermined initial position. It is possible to detect a long shooting distance.

(Third Embodiment) FIG. 3 is a block diagram showing a configuration of an interchangeable lens type single-lens reflex camera which is an example of an optical apparatus according to a third embodiment of the present invention. This is almost the same as the block diagram of the first embodiment (FIG. 1), and the photographing lens is also a single focal length lens having a fixed focal length.

The difference from the first embodiment is that a shooting distance table 7 for measuring the current shooting distance is added. Specifically, when a pulse count value is requested from the camera MPU 8, the lens MPU 1 detects the current extension position from the extension position detection unit 4 and determines the shooting distance by referring to the shooting distance table 7. Transmit to camera MPU8. As described above, since the detection of the extended position is performed by electrically dividing the distance ring of the photographing lens into regions at equal intervals, the actual photographing distance has a certain width, for example, “5.20 to 2.70 m”. Is transmitted in such a range. The photographic lens according to the third embodiment includes a lens MPU 1 to an optical information table 5 and a photographic distance table 7 as main components.

The operation of the camera is the same as that of the flowchart of FIG. 5 described in the first embodiment, except for the photographing distance measurement routine called in step # 107 of FIG. Hereinafter, this will be described with reference to the flowchart of FIG.

When the photographing distance measurement routine is called in step # 301, the flow advances to step # 302 to acquire the current pulse count value. Specifically, the encoder in the lens position detection unit 3 optically outputs one pulse per movement of the lens movable unit by a unit length as described above,
This is counted by the counter section, and the count value in the counter section indicates the current position of the lens. Lens MP
U1 obtains the current count value and sends the current count value to the camera MPU8 when the camera MPU8 requests the shooting distance.

Then, the process proceeds to a step # 303, wherein the camera MP
U8 makes a request to the lens MPU1 for the above-mentioned shooting distance, and when this shooting distance is acquired, step # 304.
Then, it is determined whether the shooting distance has changed from the previous acquisition. Here, if the shooting distance has changed since the previous acquisition, the process proceeds to step # 305. Otherwise, the process skips step # 305 and proceeds to step # 306.

In step # 305, the shooting distance conversion table 13 is updated. The photographing lens of the third embodiment is a single focus lens, and the photographing distance conversion table corresponding to the lens ID is as shown in FIG. Here, the shooting distance is “∞ to 5.20 m” at the extension position “1”.
From the range of “5.20 to 2.70” of the feeding position “2”.
m ”, the current shooting distance is almost“ 5.2
0 m ". The pulse count value at this time is stored as a reference position.

Then, the process proceeds to a step # 306, wherein the photographing distance conversion table 13 shown in FIG.
At 307, it is determined whether the shooting distance can be corrected. Here, if the pulse count value serving as the reference position is stored, the photographing distance can be corrected, so that step # 308 is performed.
Then, the shooting distance is corrected. On the other hand, if the pulse count value has not been stored, it is impossible to correct the pulse count value, so that step # 308 is skipped, and the photographing distance acquired from the photographing lens is directly ended as the final photographing distance.

The correction of the photographing distance in step # 308 is performed as follows.

As shown in FIG. 11, for example, step # 3
At 04, a change of “5.20 to 2.70 m” at the payout position “2” is detected from the range of “∞ to 5.20 m” at the payout position “1”, and the pulse count value at that time is “10 to 5.20 m”.
The case where “0” is stored as the reference position will be described.

The shooting distance conversion table 13 stores the total number of pulses in the zone at each payout position, and the defocus amount from infinity at the payout position boundary.
The total number of pulses in the zone is the number of focus pulses (the total number of pulses output from the encoder) required to move both ends of a certain feeding position. Therefore, assuming that the current pulse count value is “200”, the defocus amount D (mm) from the current infinity can be obtained by linear interpolation as follows: D = ((from the infinity of the boundary between the extending positions “2” and “3” from infinity) Defocus amount)-(Defocus amount from infinity at the boundary between the feed-out positions "1" and "2") / (Number of pulses in the zone at the feed-out position 2) x ((current pulse count value)-(Reference position) Pulse count value)) + (defocus amount from the infinity at the boundary between the feeding positions 1 and 2) = (4.000−2.000) / 200 × (200−100) + 2.000 = 3.000 In general, the subject distance H (mm) is determined by calculating the focal length of the photographing lens from the defocus amount from infinity by f.
Then, since it is expressed by H = f ² / D (1), the focal length of the photographing lens is set to 100 (m).
m), H = 3333 (mm). As described above, since the photographing distance Z (mm) is substantially equal to the sum of H and the focal length f, Z = H + f (2) = 3333 + 100 = 3433.

In the third embodiment, the total number of pulses in the zone at each extension position and the defocus amount from infinity at the extension position boundary are stored in the shooting distance conversion table 13 in advance. However, this
It may be obtained sequentially during the shooting process. That is, with respect to the total number of pulses in the zone, the pulse count value at the payout position boundary is sequentially stored in the shooting conversion table when it is determined, and when the pulse count values at both ends of the payout position are obtained, the difference is calculated from the difference. You may ask.

The defocus amount from infinity at the extension position boundary may be calculated from the above equations (2) and (1) when the photographing distance from the photographing lens changes.

According to the third embodiment, the photographing distance information is output from the photographing lens. However, as shown in FIG. 11, since the number of divisions of the distance ring is small, single-focus photographing with poor detection accuracy is performed. Focusing on the fact that the shooting distance information changes according to the shooting lens extension position of the lens, and corrects the shooting distance from the lens position after the shooting distance information changed, so it is possible to detect the shooting distance with high accuracy Become.

Further, even in a photographing lens in which photographing distance information is not output in the first place, like the sensitivity in the photographing distance conversion table shown in FIG. 11, the optical information or the extending position information which changes according to the extending position of the photographing lens. The same effect can be obtained if it is applied instead of the shooting distance.

(Fourth Embodiment) FIG. 4 is a block diagram showing the configuration of an interchangeable lens type single-lens reflex camera which is an example of an optical apparatus according to a fourth embodiment of the present invention. Although substantially the same as the block diagram of the third embodiment (FIG. 3), the photographing lens according to the fourth embodiment is a zoom lens having a variable focal length, and focus detection for detecting the current focal length. The difference is that a unit 6 is added.
The photographing lens is configured with the main components from the lens MPU 1 to the photographing distance table 7.

The operation of the camera is almost the same as that of the third embodiment, except that the processing of searching the shooting distance conversion table in step # 307 in FIG. 7 is different. Specifically, the camera MPU 8 refers to the shooting distance conversion table 13 based on the lens ID obtained in step # 102 in FIG. 5, but the shooting lens according to the fourth embodiment is a zoom lens, Shooting distance conversion table 1 corresponding to ID
3 is as shown in FIG. Therefore, similarly to the second embodiment, the focal length f (mm) is obtained, and the photographing distance is corrected by the photographing distance conversion table 13 corresponding to the focal length.

According to the fourth embodiment, focusing on the fact that the photographing distance information changes according to the extension position of the photographing lens, the photographing distance is corrected from the lens position after the photographing distance information has changed. Therefore, the photographing distance information is output from the photographing lens. However, even with a photographing lens having low detection accuracy due to a small number of divisions of the distance ring, it is possible to detect the photographing distance with high accuracy.

Further, even in a photographing lens in which photographing distance information is not output in the first place, optical information that changes according to the extension position and focal length of the photographing lens, such as the sensitivity in the photographing distance conversion table in FIG. If applied instead of the shooting distance, the same effect can be obtained.

(Fifth Embodiment) FIG. 13 is a block diagram showing a configuration of an interchangeable lens for a single-lens reflex camera which is an example of a photographing lens according to a fifth embodiment of the present invention.

In FIG. 13, reference numeral 1 denotes a lens MPU (micro processing unit) for performing all calculations and controls according to the fifth embodiment, 2 denotes a lens drive unit for driving a photographing lens, and 3 denotes a lens position. A detection unit 4 is an extension position detection unit, and 5 is an optical information table different for each interchangeable lens, such as the sensitivity, the extension amount of the lens per pulse, and the best focus correction value. 7 is a shooting distance table for measuring the current shooting distance, and 13 is a shooting distance conversion table. The photographing lens according to the fifth embodiment is a fixed focal length lens having a fixed focal length, but can be similarly applied to a zoom lens having a variable focal length. Further, an actual photographing lens requires an aperture driving unit or the like for driving the aperture, but this is not related to the present invention, so that the description is omitted.

From the lens MPU 1 to the optical information table 5, the photographing lens is constituted by using the photographing distance table 7 and the photographing distance conversion table 13 as main components.
The taking lens is connected to the camera body via a mount indicated by a dotted line in the center of the figure.

In the fifth embodiment, the processing performed by the camera MPU 8 in the third and fourth embodiments is performed by the lens MPU 1. This will be described with reference to the flowchart of FIG.

When the camera requests the photographing distance, step # 401 is called to start measuring the photographing distance. First, in step # 402, a pulse count is obtained, and in the next step # 403, an absolute distance is obtained. In all the flows, except for the addition of the correction information of the shooting distance in step # 409, Third and fourth embodiments described above
In the embodiment, the processing is the same as that performed by the camera MPU 8, and the description is omitted.

In step # 409, correction information of the photographing distance is added. This is added so that the camera can know that the shooting distance has been corrected and the measurement accuracy has been increased. Specifically, the shooting distance transmitted from the lens MPU1 to the camera side is sent as a 32-bit floating point, but as is apparent, there is no negative number in the shooting distance. Therefore, when the shooting distance is corrected, the sign is inverted and a negative number is transmitted to notify the camera that the shooting distance has been corrected. In this way, the accuracy of the output shooting distance information can be output.

In the fifth embodiment, the correction information of the photographing distance is output in this manner. However, in response to a request for confirming the correction of the photographing distance from the camera, information indicating that the correction has been performed is output. However, it can be implemented equally.

According to the fifth embodiment, the photographing distance is calculated from the extension position of the photographing lens, and the photographing distance is corrected from the lens position after the photographing distance is changed. It is possible to provide a photographic lens that can output high-precision photographic distance information even with a lens having a small amount of detection and poor detection accuracy.

(Modification) In each of the above embodiments, a single-lens reflex camera has been described. However, the present invention is applicable to other optical devices such as a video camera and an electronic still camera.

(Correspondence between the Invention and the Embodiment) In each of the above embodiments, the lens MPU 1 and the first position detection unit are replaced by the lens MPU 1 and the optical information table 5. Is the optical information output means of the present invention, the camera MPU 8 is the calculating means of the present invention, the lens MPU 1 and the focal length detecting unit 6 are the focal length detecting means of the present invention, and the lens MPU 1 and the lens position detecting unit 3 are the present invention. The lens MPU1 and the photographing distance conversion table 13 correspond to the second position detecting means, the correcting means of the present invention, and the lens MPU1 corresponds to the photographing distance information outputting means of the present invention.

The photographing distance conversion table 13 corresponds to the storage means of the present invention, the photographing distance table 7 corresponds to the storage section of the present invention, and the lens MPU 1 and the lens position detecting unit 3 correspond to the displacement detecting means and the area detecting means of the present invention. Respectively.

[0072]

As described above, claims 1 and 3,
According to the invention described in 5, 7, 8, 13, 19, or 26, in a photographing lens in which photographing distance information is not output, or in a photographing lens in which the number of divisions of a distance ring is small even if it is output, detection accuracy is poor. It is also possible to provide a photographing distance measuring device, a photographing lens, a camera system or an information processing device for a camera system capable of detecting a photographing distance with high accuracy without moving the distance ring to a predetermined initial position. It is.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an electrical configuration of a camera according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing an electrical configuration of a camera according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing an electrical configuration of a camera according to a third embodiment of the present invention.

FIG. 4 is a block diagram showing an electrical configuration of a camera according to a fourth embodiment of the present invention.

FIG. 5 is a flowchart showing an operation of a main part of the automatic focusing camera according to the first to fourth embodiments of the present invention.

FIGS. 6A and 6B show first and second embodiments of the present invention.
6 is a flowchart illustrating an operation of measuring a photographing distance performed in step # 107 of FIG.

FIG. 7 is a perspective view showing the third and fourth embodiments of the present invention.
6 is a flowchart illustrating an operation of measuring a photographing distance performed in step # 107 of FIG.

FIG. 8 is a flowchart showing an operation of a main part of a taking lens according to a fifth embodiment of the present invention.

FIG. 9 is a diagram showing a shooting distance conversion table referred to in step # 202 of FIG. 6 in the first embodiment of the present invention.

FIG. 10 is a diagram showing a shooting distance conversion table referred to in step # 202 of FIG. 6 in the second embodiment of the present invention.

FIG. 11 is a diagram showing a shooting distance conversion table referred to in steps # 304 and # 305 in FIG. 7 in the third embodiment of the present invention.

FIG. 12 is a diagram showing a shooting distance conversion table referred to in steps # 304 and # 305 of FIG. 7 in the fourth embodiment of the present invention.

FIG. 13 is a block diagram illustrating an electrical configuration of a photographic lens according to a fifth embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 lens MPU 2 lens drive unit 3 lens position detection unit 4 extension position detection unit 5 optical information table 6 focal length detection unit 7 shooting distance table 8 camera MPU 13 shooting distance conversion table

Claims (26)

[Claims] 1. A position detecting means for detecting an extended position of a photographic lens, and an optical information output means for outputting a sensitivity or a best focus correction value as optical information according to the extended position detected by the position detecting means. And a calculating means for calculating a photographing distance from the optical information from the optical information output means. 2. The photographing distance measuring apparatus according to claim 1, wherein the photographing lens is a fixed focal length lens having a fixed focal length. 3. A position detecting means for detecting an extended position of the taking lens, a focal length detecting means for detecting a focal length of the taking lens, and an extended position and the focal length detecting means detected by the position detecting means. Optical information output means for outputting a sensitivity or a best focus correction value as optical information according to the focal length detected by the optical information output means, and arithmetic means for calculating a shooting distance from the optical information from the optical information output means. A photographing distance measuring device characterized by the above-mentioned. 4. The photographing distance measuring apparatus according to claim 3, wherein the photographing lens is a lens having a variable focal length. 5. A first position detecting means for detecting an extended position of the taking lens, an arithmetic means for calculating an imaging distance from the extended position detected by the first position detecting means,
A second position detecting means for detecting a position of the taking lens after a change in the extended position is detected by the first position detecting means; and a second position detecting means for detecting a change in the extended position of the first position detecting means. Correcting means for correcting the photographing distance in accordance with a change in the lens position from the reference position based on the lens position detected by the second position detecting means, and a photographing distance for outputting the corrected photographing distance A photographing lens comprising information output means. 6. The photographing lens according to claim 5, wherein the photographing distance information output means outputs information indicating that the photographing distance has been corrected when the correcting means corrects the photographing distance. 7. A camera system comprising the photographing distance measuring device according to claim 1. 8. A camera system comprising: a camera having a lens unit for transmitting correction data to a camera, the storage device storing correction data corresponding to the extension position of the photographing lens, and a camera in the camera. A camera system comprising a storage unit for storing data corresponding to a distance, and selecting data stored in the storage unit according to the correction data transmitted from the lens device. 9. The camera system according to claim 8, wherein the storage unit stores data corresponding to the shooting distance using the correction data as a factor. 10. The camera system according to claim 8, wherein the correction data is data used for focus detection or focus adjustment. 11. The storage device stores the correction data corresponding to a plurality of divided moving regions of the photographing lens, and the lens device determines which region the photographing lens is located in. And transmitting correction data corresponding to the area to the camera.
The camera system according to any one of the above. 12. The storage unit stores data corresponding to the photographing distance for each focal length in relation to a focal length. The camera stores focal length information from the lens device and the correction data. The camera system according to any one of claims 8 to 11, wherein data stored in the storage unit is selected in accordance with the data. 13. A method according to claim 1, wherein data corresponding to a photographing distance set corresponding to each of the plurality of divided moving regions of the photographing lens and a switching position of the moving region are set as reference positions in the photographing lens region. And a calculating means for calculating data corresponding to the photographing distance based on the displacement detected by the displacement detecting means for detecting the displacement from the reference position in the camera system. Information computing device. 14. An image forming apparatus, comprising: an area detecting means for detecting which area of the moving area the photographing lens is located in, wherein the calculating means comprises: data corresponding to an area detected by the area detecting means; 14. The apparatus according to claim 13, wherein data corresponding to the photographing distance is calculated based on the obtained displacement amount.
An information processing device for a camera system according to item 1. 15. The displacement amount detecting means has a counter section for detecting a movement of the photographing lens and updating a count value each time the photographing lens moves by a predetermined amount. 15. The method according to claim 14, wherein when the change of the area is detected, the count value at the detected reference position is set as the count value of the origin, and the displacement amount is detected based on a subsequent change amount of the count value.
An information processing device for a camera system according to item 1. 16. The data set corresponding to each of the regions is data at a boundary position in the region, and the calculating means performs, in the calculation, the data of the region where the photographing lens is located and the data of the region. 16. The information processing device for a camera system according to claim 14, wherein data corresponding to a shooting distance is calculated based on a difference between data in a contact area and the displacement amount. 17. The computing means according to claim 1, wherein:
Photographing is performed based on the ratio of the displacement amount in the entire region where the photographing lens is located to the displacement amount detected by the displacement amount detecting means, and the difference between the data in the region where the photographing lens is located and the data in the region in contact with the region. 17. The apparatus according to claim 16, wherein data corresponding to the distance is calculated. 18. The apparatus according to claim 13, wherein the data corresponding to the photographing distance set corresponding to each of the plurality of divided moving regions of the photographing lens is a defocus amount from infinity. An information processing device for a camera system according to any one of claims 17 to 17. 19. A camera having storage means for storing data corresponding to a shooting distance set corresponding to each of a plurality of divided moving regions of a photographing lens, and a switching position of the moving region as a reference. In a camera system comprising, as a position, a photographing lens device having a displacement amount detecting means for detecting a displacement amount from a reference position in a region of the photographing lens, the displacement amount detected by the displacement amount detecting means And a calculating means for calculating data corresponding to a shooting distance based on the data in the area where the shooting lens is stored, stored in the storage means. 20. An image processing apparatus, comprising: an area detecting unit that detects an area of the moving area in which the photographing lens is located, wherein the calculating unit calculates data corresponding to an area detected by the area detecting unit and 20. The camera system according to claim 19, wherein data corresponding to a shooting distance is calculated based on the detected displacement amount. 21. The displacement amount detecting means has a counter section for detecting movement of the photographing lens and updating a count value each time the photographing lens moves by a predetermined amount. The method according to claim 1, wherein when the change of the lens area is detected, the count value at the detected reference position is set as the count value of the origin, and the displacement amount is detected based on a change amount of the count value thereafter. 20. The camera system according to 19. 22. The data set corresponding to each of the areas is data at a boundary position in the area, and the calculating means performs the calculation by calculating the data of the area where the photographing lens is located and the area. 22. The camera system according to claim 20, wherein data corresponding to a photographing distance is calculated based on a difference between the data and an amount of displacement in an area in contact with the object. 23. The computing means according to claim 23, wherein:
Based on the difference between the data of the area where the photographing lens is located and the data of the area in contact with the area and the ratio of the displacement amount in the entire area where the photographing lens is located and the displacement amount detected by the displacement amount detecting means, The camera system according to claim 22, wherein data corresponding to a shooting distance is calculated. 24. Data according to claim 19, wherein the data corresponding to the photographing distance set corresponding to each of the plurality of divided moving regions of the photographing lens is a focus amount from infinity. The camera system according to any one of the above. 25. The storage means stores data corresponding to the photographing distance for each focal length in relation to the focal length, and the calculating means stores the data according to the area where the photographing lens is located and the focal length. Selecting data stored in the storage means and calculating data corresponding to the photographing distance based on the selected data and the displacement detected by the displacement detection means. Item 20. The camera system according to item 19. 26. Data corresponding to a photographing distance set corresponding to each of the plurality of divided moving regions of the photographing lens, and a switching position of the moving region as a reference position within a region of the photographing lens. A camera system comprising: a calculating unit that calculates data corresponding to a photographing distance based on a displacement amount detected by a displacement amount detecting unit that detects a displacement amount from a reference position in the camera and a focal length. Information processing device for