JP3213971B2 - Auto focus camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera provided with an automatic focusing device.

[0002]

2. Description of the Related Art The amount of defocus of a photographing lens is detected,
Determine whether the subject is still or moving based on the detected latest and past multiple defocus amounts, and if determined to be still, drive the lens to focus the taking lens based on the latest defocus amount. The amount is obtained, and the driving of the photographing lens is controlled according to the amount of driving. On the other hand, if the movement is determined, the lens drive amount for tracking the photographing lens to the moving subject is obtained based on the latest and past defocus amounts of a plurality of times, and the drive control of the photographing lens is performed in accordance with this drive amount. Focusing cameras are known.

Further, focusing or non-focusing of the photographing lens is determined based on the detected latest and plural defocus amounts in the past, and once the focusing is determined, driving of the photographing lens is prohibited ( An automatic focus adjustment camera that releases focus lock when movement of a subject is detected during focus lock is known.

Further, the defocus amount of the photographing lens in a plurality of focus detection areas at the center of the photographing screen and at a place other than the center is detected, and the closest, current priority, average, etc. are obtained from the obtained defocus amounts. An automatic defocus amount is determined in accordance with an algorithm, and based on the latest and past optimum defocus amounts for a plurality of times, determination of still movement of a subject, calculation of a lens driving amount, and driving of a photographing lens are performed in the same manner as in the above camera. Conditioned cameras are known.

[0005]

However, the above-mentioned conventional automatic focusing camera has the following problems. When selecting the optimal defocus amount from the defocus amounts of multiple focus detection areas in the shooting screen, the stability of stationary movement judgment when an unnecessary subject enters part of the focus detection area after focusing once In order to improve the defocus amount, it is conceivable to select the defocus amount having the minimum absolute value and determine the still movement of the subject based on the selected latest and past plural defocus amounts. However, in a state where the main subject is small and is captured only in a part of the plurality of focus detection areas, when a subject that has been stationary at the same distance as the background at the time of focusing starts moving thereafter, the movement determination for the subject is determined. I can't do it and stay focused on the background forever.

When the image plane speed of a subject is calculated based on the latest and past defocus amounts of a plurality of focus detection areas in a photographing screen, and drive control of the photographing lens is performed based on this image plane speed, If there are moving subjects with different speeds in a plurality of focus detection areas, the image plane speed may be calculated for each different moving subject for each focus detection, resulting in a large hunting of the lens, resulting in poor usability.

When the still movement of a subject is determined based on the latest and past defocus amounts of a plurality of focus detection areas in a photographing screen and the drive control of the photographing lens is performed based on the decision result, a plurality of If a stationary subject and a moving subject are mixed in the focus detection area, the drive control of the photographing lens may be performed for different subjects for each detection, and as a result, the lens is largely hunted and the stability is poor. It is also conceivable that once focus is determined with emphasis on stability, focus locking may be performed thereafter, but detection of a subject that has started moving after focus lock cannot be performed.

An object of the present invention is to provide a lens for a moving subject.
Another object of the present invention is to improve the stability and responsiveness of the nozzle drive .

[0009]

Means for Solving the Problems The invention of claim 1 will be described in association with FIG. 1 which is a claim correspondence diagram.
According to the invention, a focus detection unit 101 that repeatedly detects a plurality of defocus amounts in a plurality of focus detection areas set in a shooting screen, and a defocus amount that indicates the closest of the plurality of defocus amounts. Lens driving means 1
In the closest state of driving the taking lens according to 05,
First movement determining means 102 for determining the movement of the subject based on a temporal change in the defocus amount indicating the closest distance;
In the current priority state in which the lens driving unit 105 drives the taking lens based on the defocus amount indicating the absolute value minimum among the plurality of defocus amounts, based on the time change of the defocus amount indicating the absolute value minimum If the second and third movement determining means 102 and 103 determine that the subject is moving, the data used for the determination is determined. The image plane speed of the subject for tracking the moving subject is calculated based on the focus amount, and the photographing lens is driven by the lens driving unit 105 based on the subject image plane speed, whereby the closest state or the current state priority is calculated. Control means 104 for shifting from the state to the tracking state.

The invention of claim 2 will be described in association with FIG. 2 which is a claim correspondence diagram. The invention of claim 2 repeats a plurality of defocus amounts in a plurality of focus detection areas set in a photographing screen. Focus detecting means 201 for detecting
Calculating the image plane speed of the subject in the plurality of focus detection areas based on the plurality of defocus amounts and one defocus amount selected from the plurality of defocus amounts at the time of past focus detection. Image plane speed calculation means 202
And an image plane speed estimating means 20 for calculating the current estimated object image plane speed based on the object image plane speed of the focus detection area corresponding to one defocus amount selected at the time of past focus detection.
And selecting a subject image surface speed closest to the expected subject image surface speed from the subject image surface speeds calculated in the plurality of focus detection areas, and tracking the moving subject based on the selected subject image surface speed. And a lens drive control unit 204 for driving the photographing lens.

The invention of claim 3 will be described with reference to FIG. 3 which is a claim correspondence diagram. In the automatic focusing camera according to claim 3, the image plane speed calculation means 202A controls the plurality of defocus amounts. , The defocus amount of the focus detection area indicating the subject image surface speed closest to the expected subject image surface speed is selected.

[0012]

According to the first aspect, the movement of the subject is determined based on the time change of the defocus amount indicating the closest in the closest state, and based on the time change of the defocus amount indicating the minimum absolute value in the current priority state. To determine the movement of the subject, and if it is determined that the subject is moving,
Calculates the image plane speed of the subject to track the moving object based on the defocus amount used for the determination, and drives the taking lens based on the image plane speed of the subject to change from the closest state or the current priority state. Move to tracking state.

According to a second aspect, a plurality of defocus amounts;
Based on one defocus amount selected from a plurality of defocus amounts at the time of past focus detection, image plane velocities of a subject in a plurality of focus detection areas are calculated, and one defocus amount selected at the time of past focus detection is detected. The current expected subject image surface speed is calculated based on the subject image surface speed of the focus detection area corresponding to the focus amount, and the most estimated subject image surface speed is calculated from the subject image surface speeds calculated in the plurality of focus detection regions. A near subject image plane speed is selected, and the photographing lens is driven to track the moving subject based on the selected subject image plane speed.

According to a third aspect of the present invention, a defocus amount of a focus detection area indicating a subject image surface speed closest to the expected subject image surface speed is selected from a plurality of defocus amounts.

[0015]

FIG. 4 is a block diagram showing the configuration of one embodiment. AFCPU1 is a microcomputer that performs arithmetic processing of automatic focus adjustment and lens control, and a main CPU.
Reference numeral 2 denotes a microcomputer for performing sequence control such as exposure control, film winding, and shutter charge. The taking lens 3 is a lens whose focus can be adjusted by moving in the optical axis direction. The distance setting device 11 is a setting device for setting a subject distance desired by the photographer, and the set distance information is sent to the AF CPU 1. The magnification setting device 12
This is a setting device for setting a photographing magnification desired by the photographer, and the set magnification information is sent to the AFCPU1. The AF sensor 13 includes a focus detection optical system and a photoelectric conversion element. The subject image corresponding to the light intensity distribution of the subject image formed in a plurality of regions on the screen by a light beam passing through the photographing lens 3. Generate a signal. AFCPU1 is
A well-known calculation process is performed on the subject image signal to detect a defocus amount of a subject image plane formed in a plurality of regions on the screen with respect to a predetermined focal plane (film plane).

FIG. 5 shows a configuration example of the AF sensor 13. A
The F sensor 13 includes a field mask 40 and a field lens 4
One and two pairs of re-imaging lenses 42A, 42B, 43A,
A focus detection optical system 44 composed of 43B, and two pairs of light receiving units 4
5A, 45B, 46A and 46B and a photoelectric conversion element 47 such as a CCD. In the above configuration, two pairs of regions 35A, 35B, 36A, 36 symmetric with respect to the optical axis 34 included in the exit pupil 33 of the photographing lens 3.
The light beam passing through B forms a primary image near the field mask 40 having an opening corresponding to the focus detection area shown in FIG. Part of the primary image formed in the opening of the field mask 40 is further divided into a field lens 41 and two pairs of re-imaging lenses 4.
The photoelectric conversion element 47 is formed by 2A, 42B, 43A, 43B.
On the two pairs of light receiving sections 45A, 45B, 46A, 46B.
Formed as a pair of secondary images.

As is well known, the relative positional relationship of the paired secondary images on the photoelectric conversion element 47 in the arrangement direction of the light receiving portions is
By detecting using the subject image signal generated by the photoelectric conversion element 47, the defocus amount of the photographing lens 3 can be detected. In addition, by detecting this positional relationship for each of a plurality of focus detection areas set on the shooting screen as shown in FIG. 6, the defocus amount can be detected for each focus detection area.

FIG. 6 shows a plurality of focus detection areas set in a vertical and horizontal cross at the center of the screen.
F5 to F5, and a total of eight areas F6 to F8 are set in the short side direction, and the defocus amount is detected in each area. FIG. 7 shows another example in which the focus detection areas at the left and right of the screen are added to the focus detection area at the center of the screen. Areas F9 to F11 in the short side direction on the left side of the screen and areas F12 to F in the short side direction on the right side of the screen
14 is set.

Returning to FIG. 4, the description will be continued. The motion detection device 14 is configured by a known acceleration sensor or the like, and detects motion or blur of a lens or a body. The output of the motion detection device 14 is sent to the AFCPU1,
The movement (position change) of the lens or the body is determined.
The motor 15 receives a drive control signal from the AF CPU 1 and moves the focusing lens of the photographing lens 3 in the optical axis direction via a gear system (not shown). AFCPU1 is
The driving direction and the driving amount of the motor 15 are controlled according to the defocus amount, and the photographing lens 3 is focused. The distance detection device 31 is a device that encodes the absolute position of the focusing lens of the photographing lens 3, and the encoded signal is sent to the AFCPU 1 to detect the subject distance where the focusing lens is set at the current position. The focal length detecting device 32 is a device that encodes the absolute position of the zoom lens of the photographing lens 3, and the encoded signal is sent to the AFCPU 1 to detect the focal length at which the zoom lens is set at the current position. .

The release button 20 is an operating member for activating an automatic focus adjustment operation by half-pressing and activating an exposure operation (photographing operation) by full-pressing. Move on. When the release button 20 is half-pressed, a half-press signal is sent to the AF CPU 1, and when the release button 20 is fully pressed, a full-press signal is sent to the main CPU 2. AFCPU1 generates an A signal and outputs the signal to the main CPU.
Request the start of the exposure operation to 2 and set the frame speed at the time of continuous shooting. The frame speed setting device 21 is a setting device for externally setting a frame speed and a winding mode for continuous shooting, and the set frame speed and winding mode information are sent to the main CPU 2. In response to a full-press signal of the shutter button 20 or an A signal from the AF CPU 1, the main CPU 2 responds to luminance information and exposure control mode information obtained from a photometric device (not shown) to control the aperture mechanism unit 33 and the shutter mechanism unit 22. Control. At the time of exposure, it controls the winding device 23, the shutter charging mechanism 24, and the mirror mechanism 25. Further, the timing information of these sequences is sent to the AFCPU 1 as an M signal.

Next, various quantities used in this embodiment are defined as follows. FIG. 8 shows the movement X1 of the ideal image plane of the moving subject.
FIG. 9 is a diagram showing a movement X2 of an image plane when the photographing lens 3 is driven by performing an automatic focusing operation. The definitions of various quantities will be described with reference to FIG. (1) The suffix n represents the number of focus detection operations.
n = 1, 2, 3, ... (2) The plurality of defocus amounts detected in the plurality of focus detection areas in the focus detection operation are represented by da, db,.
z. However, the sign of the defocus amount in the back focus state is +. A plurality of defocus amounts da, db,
.., Dz are obtained based on the output of the AF sensor 13 during the same accumulation time. In some cases, the focus cannot be detected and the defocus amount cannot be detected. In this case, da =
＠, db = ＠,..., Dz = ＠. (3) The time at the midpoint of the charge accumulation period is tn-1, tn, t
.., n + 1,.

(4) A plurality of defocus amounts da, db,
.., Dz is determined by the selected defocus amount d as a result of the n-th focus detection.
n. The defocus amount dn is obtained by completing the calculation at time ten which is later than time tn. (5) A plurality of defocus amounts da, db,..., Dz
Among these, the defocus amount indicating the closest distance is defined as the closest defocus amount rn. rn = MAX (da, db,..., dz) (1) However, when focus detection is not possible, rn = ＠. In the calculation of the closest defocus amount rn, a focus detection area (for example, the area F2 in FIG. 6) in which the focus detection area is near the center of the screen among the plurality of defocus amounts da, db,. The closest defocus amount when the defocus amount is limited to F4, F6 to F8, and regions F1 to F8 in FIG. Further, a plurality of defocus amounts da, d
It is assumed that b,..., dz are obtained based on the output of the AF sensor 13 during the same accumulation time. However, when the respective defocus amounts are obtained based on the outputs during different accumulation times, As described later, if different overlap correction amounts are calculated according to the respective accumulation times and overlap correction is performed, a defocus amount indicating the closest distance is selected from a plurality of defocus amounts after the overlap correction. Good.

(6) A plurality of defocus amounts da, db,
.., Dz, a defocus amount that indicates the closest distance with a defocus amount equal to or more than a predetermined value K4 and equal to or less than K5 is defined as a closest defocus amount sn. sn = MAX (ba, bb,..., bz) (2) where ba, bb,..., bz are K4 <(da,
db,..., dz) <K5. For example, if K4 <da <K5, ba = da, otherwise, there is no ba. When the focus cannot be detected or when ba, bb,...
Expressed as n = ＠. In the above calculation of the closest defocus amount sn, a plurality of defocus amounts da, db,.
In z, the focus detection area is close to the focus detection area near the center of the screen (for example, the areas F2 to F4, F6 to F8 in FIG. 6, and the areas F1 to F8 in FIG. 7). The defocus amount is s'n. Predetermined values K4, K
The reason for setting the limit of 5 is to detect only the subject that emerges from the background without being greatly affected by a nearby obstacle, for example, K4 = −4 mm, K5 = 4 mm.
About. Further, K4 and K5 may be adjusted in consideration of the lens focal length, magnification, luminance, and current focus detection time (presence or absence of release). The closest defocus amount sn is used for tracking determination of a subject that partially emerges from the background in a current priority state described later.

(7) The overlap correction amount Dc is a difference Lc = Len-La between the average lens position Lan during the accumulation time and the lens position Len at the defocus amount calculation time ten.
This is an amount obtained by converting n into an image plane movement amount. Dc = C * Lc where C is a conversion factor. (3) It is assumed that the relationship between the lens movement amount and the image plane movement amount is substantially linear regardless of the lens position and the object position. Further, a plurality of defocus amounts da, db,..., Dz
Is assumed to have been obtained based on the output of the same accumulation time of the AF sensor 13, but if the respective defocus amounts are obtained based on the outputs of different accumulation times, A different overlap correction amount will be calculated. (8) A plurality of defocus amounts da, db,..., Dz
The defocus amount that shows the minimum absolute value among the defocus amounts obtained by correcting the overlap with the current priority defocus amount p
n. For example, | db-Dc | = MIN (| da-
Dc |, | db-Dc |, ..., | dz-Dc |), pn = db. When the focus cannot be detected, pn =
Expressed as ＠. In calculating the current priority defocus amount pn, a plurality of defocus amounts da, db,.
7, the focus detection area whose focus detection area is near the center of the screen (for example, the areas F2 to F4, F6 to F8, and FIG.
When the defocus amount is limited to the regions F1 to F8)
The current priority defocus amount is p'n.

(9) Correction defocus amount D (n-1) n
Is an amount obtained by converting the lens movement amount L (n-1) n driven between times t (n-1) and tn into an image plane movement amount. D (n-1) n = C * L (n-1) n (5) When n = 1, D (n-1) n = 0. (10) The image plane speed V (n-1) n is the time t (n-1)
And the speed at which the image plane moves between tn. When the two defocus amounts d (n-1) and dn are determined, the image plane speed V (n-1) n is obtained as follows. V (n−1) n = (dn + D (n−1) n−d (n−1)) / (tnt−n (n−1)) (6) where two defocus amounts d ( n-1), dn = ＠
And in the case of n−1, V (n−1) n = ＠. In the above description, the image plane speed is calculated from two consecutive defocus amounts. However, if the detection time interval is short, the calculation result includes an error and the reliability is lost.
Every other time interval may be longer.

(11) Current image surface speeds Va, Vb,...
.., Vz are a plurality of defocus amounts d detected this time
a, db,..., dz. Va = (da + D (n−1) nd− (n−1)) / (tn−t (n−1)) (7) Vb = (db + D (n−1) nd−n (n−) 1)) / (tn-t (n-1)) (8) Vz = (dz + D (n-1) nd (n-1)) / (tn-t (n-1) )) (9) where defocus amount d (n−1) or da, d
b,..., dz = ＠ and n = 1, V
a, Vb,..., Vz = ＠. (12) The current expected image surface speed Vf (n-1) n is an image surface speed determined in consideration of continuity from the previous image surface speed V (n-2) (n-1). Vf (n−1) n = α * V (n−2) (n−1) + β (10) However, when V (n−2) (n−1) = ＠, Vf
(N-1) Let n = ＠. The coefficients α and β are the image plane movement direction, lens focal length, magnification, image plane acceleration, luminance, current focus detection time (whether release is used), and the ratio of the previous and current focus detection time intervals (whether release is used) ) To adjust.

(13) A plurality of defocus amounts da and d
The defocus amount that optimizes the continuity of the image plane speed from b,..., dz is defined as a tracking defocus amount fn. That is, of the current image surface velocities Va, Vb,..., Vz, the defocus amount that minimizes the difference from the expected image surface speed Vf (n−1) n is set as the current tracking defocus amount fn. . For example, | Vf (n-1) n-Vb | = MIN (| Vf (n-1) n-Va |, | Vf (n-1) n-Vb |, ..., | Vf (n-1 ) N−Vz |) (11), fn = db. Where Vf (n−2) (n
-1) = ＠, or Va, Vb,..., Vz =
In the case of ＠, fn = ＠. In addition, continuity of the focus detection area may be introduced to improve tracking stability. For example, in the above-mentioned determination, priority is given to the image surface speed of the focus detection area adopted last time among Va, Vb,... Restrict.

(14) Nearest image plane speed Vs (n-1) n
Is the speed at which the close image plane moves between times t (n-1) and tn. Two closest defocus amounts s (n-1),
When sn is determined, the closest image plane speed Vs (n-1) n is obtained as follows. Vs (n-1) n = (sn + D (n-1) ns- (n-1)) / (tnt-n (n-1)) (12) where two defocus amounts s ( n-1) or sn
= ＠ and n = 1, Vs (n−1) n = ＠. The closest image plane speed Vs (n-1) n is
This is used for tracking determination of a subject that partially emerges from the background in the current priority state.

The operation will be described using the definitions of the various quantities described above. In the apparatus of the embodiment, there are five operation states, and FIG.
Each operation state transitions as shown in FIG. Note that these operations are controlled by the AFCPU1. [Non-operation state] In this state, the focus detection operation is not performed. Therefore, the defocus amount is not detected. To increase the response after the release button 20 is half-pressed,
The focus detection may be performed by prohibiting the lens driving and display, and the same operation as in the closest state may be performed. [Closest state] A plurality of defocus amounts da, db,.
, Dz, the current closest defocus amount rn is selected as the current selected defocus amount dn. This operation is referred to as focus detection 1. dn = rn

[Present state in the present state] A plurality of defocus amounts d obtained from sensor outputs by accumulating the AF sensor 13
a, db,..., dz, a plurality of defocus amounts da, db,.
··· Selects the defocus amount pn that minimizes the absolute value among the defocus amounts obtained by correcting the overlap of dz. This operation is referred to as focus detection 2. dn = pn [Tracking state] The accumulation operation of the AF sensor 13 is performed, and a plurality of defocus amounts da, db,.
The defocus amount fn that optimizes the continuity of the image plane speed is selected from dz. This operation is referred to as focus detection 3. dn = fn [Focus focus lock state] A plurality of defocus amounts d obtained from the sensor output by accumulating the AF sensor 13
a, db,..., dz, a plurality of defocus amounts da, db,.
··· Selects the defocus amount pn that minimizes the absolute value among the defocus amounts obtained by correcting the overlap of dz. This operation is referred to as focus detection 2. dn = pn In the in-focus focus locked state, the lens driving is prohibited, and the display is locked with the in-focus display. Therefore, the overlap correction amount becomes zero. Except for the automatic switching mode described later, the focus lock state and the non-operation state are substantially the same. In the automatic switching mode, the focus state may shift from the focus lock state to the tracking state.

The accumulation operation of the AF sensor 13 in the above state is performed only when the mirror is down according to the M signal from the main CPU 2.

The following are conditions for judging the transition of each operation state. In the following, YES indicates that the result of the determination is affirmative, and NO indicates that the result of the determination is negative. [In-focus determination 1] YES: The absolute value of the latest closest defocus amount rn is smaller than the predetermined value K1. | Rn | <K1 NO: The absolute value of the latest closest defocus amount rn is equal to or greater than a predetermined value K1. | Rn | ≧ K1 [focus determination 2] YES: the absolute value of the latest current priority defocus amount pn is smaller than the predetermined value K2. | Pn | <K2 NO: The absolute value of the latest current priority defocus amount pn is equal to or greater than a predetermined value K2. | Pn | ≧ K2 In order to improve the temporal stability of focus determination 2,
It is also conceivable to take the past current priority defocus amount and the weighted average. In this case, the current time average defocus amount pn 'is as follows. pn '= (w0 * pn + w1 * p (n-1) + .. + wm * p (nm)) / ws (13) ws = w0 + w1 +. + wm (14) The range of the defocus amount used for taking is the defocus amount when the focus determination 2 is continuous, that is, when the lens is stopped. Focus determination 2 for the time average defocus amount thus obtained
Will be done.

[Focus determination 3] YES: The absolute value of the latest current priority defocus amount pn is smaller than a predetermined value K3. | Pn | <K3 NO: The absolute value of the latest current priority defocus amount pn is equal to or greater than a predetermined value K3. | Pn | ≧ K3 Note that the above coefficient is K1 <K2 <K3. Also K1,
K2 and K3 may be adjusted in consideration of the lens focal length, magnification, brightness, current focus detection time (presence or absence of release), and the like. [Focus determination 4] YES: YES in focus determination 3 occurred N times in the past. NO: Other than above

Tracking determination means determining whether the subject is stationary or moving. If the subject is moving, lens drive control for tracking the subject is started. [Tracking determination 1] YES: d (n-2), d (n-1), dn} and | d (n-2) |, | d (n-1) |, | dn | <dk and , V (n-2) (n-1), V (n-1) n} and | V (n-2) (n-1) |> Vk and | V (n-1) n | > Vk and 0 <Kmin <V (n−2) (n−1) / V (n−1) n <Kmax The condition is that if the image plane is far apart, the calculated image plane velocity This is for avoiding the tracking judgment because the reliability of the tracking is low. Under other conditions, a difference may be used instead of the ratio of the two image surface velocities. Further, predetermined values dk, Vk,
Kmin and Kmax are the image plane movement direction, lens focal length, magnification, image plane acceleration, luminance, current focus detection time (presence or absence of release), and the ratio of previous and current focus detection time intervals (presence or absence of release). Adjust by adding NO: Other than above

[Tracking judgment 2] YES: s (n-2), s (n-1), sn ≠ ＠ and | s (n-2) |, | s (n-1) |, | sn | <Dk and Vs (n-2) (n-1), Vs (n-1) n} and Vs (n-2) (n-1)> Vk and Vs (n-1) n> Vk and 0 <Kmin <Vs (n−2) (n−1) / Vs (n−1) n <Kmax The condition is that if the image plane is far apart, the calculated image plane speed This is for avoiding tracking determination because of low reliability. The other condition is to limit the tracking determination only when the subject approaches. Further, a difference may be used in place of the ratio of the two image plane velocities under the above condition. The predetermined values dk, Vk, Kmin, and Kmax are the image plane moving direction, lens focal length, magnification, image plane acceleration, luminance, current focus detection time (presence or absence of release), and the ratio of the previous and current focus detection time intervals ( (With or without release). NO: Other than above

[Tracking Judgment 3] Instead of the selected defocus amount dn in the tracking judgment 1, the closest defocus amount r'n of the center priority in the closest state, and the current priority defocus amount of the center priority in the current priority state. Using p'n, a determination similar to tracking determination 1 is made based on the defocus amount and the image plane speed calculated from the defocus amount. In addition,
If the above determination is NO, tracking determination 1 may be performed. With this configuration, it is possible to preferentially determine the still movement of the subject in the focus detection area at the center of the screen among the focus detection areas. [Tracking Judgment 4] Instead of the closest defocus amount sn in the above-described tracking judgment 2, the closest defocus amount s′n of the center priority is used, and the defocus amount and the image plane speed calculated from the defocus amount are used. A determination similar to tracking determination 2 is performed based on the determination. Note that the tracking determination 2 may be performed when the above determination is NO. With this configuration, it is possible to preferentially determine the still movement of the subject in the focus detection area at the center of the screen among the focus detection areas.

Next, the lens drive control will be described. [Lens drive 1] This is lens drive control in the closest state and the current priority state, and controls the lens movement amount Lx. Lx = Ln−Lc (15) Here, the lens movement amount Ln is an amount obtained by converting the currently selected defocus amount dn into a lens movement amount. Ln = dn / C (16) [Lens drive 2] Lens drive control (speed control type) in the tracking state, and the amount of lens movement until the movement of the ideal image plane matches the movement of the actual image plane (Full speed), and after the movement of the image plane coincides, the movement speed is controlled to follow the movement of the ideal image plane. Lx = Ln−Lc + V (n−1) n * t / C (17) where t is the elapsed time from the middle point of the accumulation time. Even after catching up with the target, the target lens movement amount is updated by a timer interrupt that takes place at regular intervals. Alternatively, speed control may be performed in real time.

Another example of the above-described lens drive 2 will be described. [Lens drive 2A] This is a lens drive control (overlap control type) in the tracking state, and after a predetermined time Tx from the time of the middle point of the current accumulation time (time has already elapsed until the calculation of the defocus amount). , The lens movement amount Ln is determined so that the image planes coincide. Lx = Ln−Lc + V (n−1) n * Tx / C (18) In the lens drive 2, when lens driving means is built in the taking lens 3 side, The information of the current defocus amount dn and the image surface speed V (n-1) n is transmitted from the body side to the photographing lens 3, and the photographing lens 3 controls the above-described lens drive 2 according to the information. Can be. With this configuration, it is not necessary to uniformly control various types of interchangeable lenses on the body side, and lens drive control optimized for each lens can be performed. It is particularly effective for special lenses such as micro lenses.

FIG. 9 is a state transition diagram in the continuous mode (no focus lock after focusing).
The transition between the states will be described. A: When the shutter release half-press signal is OFF,
Shift from the current priority and tracking state to the non-operation state. The initial state when the power is turned on is a non-operating state. B: When the shutter release half-press signal is ON, the state changes from the non-operation state to the closest state. C: When tracking determination 1 is NO and focusing determination 1 is NO,
The lens drive 1 (normal drive) is performed, and the closest state is maintained. D: When the tracking determination 1 is NO and the focusing determination 1 is YES, the state shifts from the closest state to the current priority state without driving the photographing lens 3. E: If the tracking determination 1 is YES, the lens drive 2 (tracking drive) is performed to shift from the closest state to the tracking state. F: If the tracking determination 1 is NO, the tracking determination 2 is NO, and the focusing determination 2 is YES, the current priority state is maintained without driving the photographing lens 3. G: If tracking determination 1 is NO, tracking determination 2 is NO, focus determination 2 is NO, and focus determination 3 is YES, lens drive 1 (normal drive) is performed to maintain the current priority state.

H: When the tracking determination 1 is NO, the tracking determination 2 is NO, the focusing determination 2 is NO, and the focusing determination 3 is NO, first, the currently selected defocus amount is changed from dn = pn to dn = rn, and lens drive 1 (normal drive) is performed to shift from the current priority state to the closest state. I: When the tracking determination 1 is YES or the tracking determination 2 is YES, when the tracking determination 2 is YES, the currently selected defocus amount dn = p so as not to cause any trouble in transition to the tracking state.
n to dn = sn, and the image plane speed V (n-1) n = Vp (n
-1) n is rewritten to V (n-1) n = Vs (n-1) n. Then, lens drive 2 (tracking drive) is performed, and the state shifts from the current priority state to the tracking state. J: If the tracking determination 1 is YES, lens driving 2 (tracking driving) is performed to maintain the tracking state. K: If the tracking determination 1 is NO, change the currently selected defocus amount dn = pn to dn = rn. Then, lens driving 1 (normal driving) is performed to shift from the tracking state to the closest state.

FIGS. 11 and 12 are flowcharts showing an example of an automatic focus adjustment control program in the continuous mode. The operation in the continuous mode will be described with reference to these flowcharts. [Non-operating state] In step S100, the power is turned on.
Then, the process proceeds to step S101 (non-operating state). In step S101, when the half-press signal is ON, the process proceeds to step S102 (transition to the closest state). [Closest-to-close state] In step S102, focus detection 1 is performed, and in step S103, tracking determination 1 is performed. If affirmative, the process proceeds to step S120 (transition to tracking state),
If not, the process proceeds to step S104. Step S10
In step 4, focus determination 1 is performed, and if affirmative, step S1 is performed.
The process proceeds to step 10 (transition to the current priority state), and if not, the process proceeds to step S105. After performing lens drive 1 in step S105, the process returns to step S102.

[Current priority state] In step S110, focus detection 2 is performed, and in step S111, tracking determination 1 is performed. If the result of determination is affirmative, step S1
The process proceeds to step 20 (transition to the tracking state), and if negative, the process proceeds to step S112. In step S112, tracking determination 2 is performed, and if affirmative, the process proceeds to step S120 (transition to a tracking state). It is assumed that the selected defocus amount dn = sn and the image plane speed V (n-1) n = Vs (n-1) n. Also,
When step S112 is denied, step S113
The focus determination 2 is performed by proceeding to step S1.
The process returns to step S10. If the result is negative, the process proceeds to step S114. In step S114, in-focus determination 3 is performed. If the determination is affirmative, the process proceeds to step S115. If the determination is negative, step S105 is performed.
Go to (closest state). It is assumed that the selected defocus amount dn = rn. After performing lens drive 1 in step S115, the process returns to step S110.

[Tracking state] In step S120,
Lens drive 2 is performed, and focus detection 3 is performed in the following step S121. In step S122, tracking determination 1 is performed,
If affirmed, the process returns to step S120, and if denied, the process proceeds to step S105 (transition to the closest state). It is assumed that the selected defocus amount dn = rn. As described above, in the current priority state, even when a part of the focus detection area comes out of the background and approaches by the tracking determination 2, it is possible to reliably determine the still movement of the subject.

FIGS. 13 and 14 are flowcharts showing another example of the control program in the continuous mode. 11 and 12 are different from those in the continuous mode shown in FIGS. 11 and 12 only in tracking determination in the closest state and the current priority state. explain. Step S
At 103, a tracking determination 3 is performed.
Proceed to 120 (transition to tracking state). Note that the selected defocus amount dn = r'n, and the image plane speed V (n-1) n = Vr '
(N-1) Let n. If step S103 is denied, the process proceeds to step S104. In step S111, tracking determination 3 is performed, and if affirmative, step S120 is performed.
To (tracking state). Selection defocus amount dn =
p'n, image plane speed V (n-1) n = Vp '(n-1) n
And If step S111 is denied, the process proceeds to step S112. In step S112, tracking determination 4 is performed, and if affirmative, the process proceeds to step S120 (transition to a tracking state). It is assumed that the selected defocus amount dn = s'n and the image plane speed V (n-1) n = Vs' (n-1) n. If step S112 is denied, the process proceeds to step S113.

By changing the continuous mode as described above, the transition to the tracking state is always based only on the defocus amount of the focus detection area near the center of the screen, or these defocus amounts are given priority. Will be performed. That is, since the stationary movement determination is performed in the spot-like area near the center of the screen, it is easy to capture the moving subject. After shifting to the tracking state,
By limiting the focus detection area to the vicinity of the center of the screen in tracking determination 1 in step S122, the tracking determination may be performed only near the center of the screen.

FIG. 10 is a state transition diagram in the single mode (with focus lock after focusing). The transition between the states will be described. A: Nearest when the half-press signal is OFF, priority on current status, tracking status,
Move from the in-focus focus locked state to the non-operating state. The initial state when the power is turned on is a non-operating state. B: The state changes from the non-operation state to the closest state by the half-press signal ON. C: When tracking determination 1 is NO and focusing determination 1 is NO,
Lens drive 1 (normal drive) is performed to maintain the closest state. D: When the tracking determination 1 is NO and the focusing determination 1 is YES, the lens is not driven, and the state shifts from the closest state to the current priority state. E: If the tracking determination 1 is YES, the lens drive 2 (tracking drive) is performed to shift from the closest state to the tracking state. F: If the tracking determination 1 is NO, the tracking determination 2 is NO, and the focusing determination 2 is YES, the current priority state is maintained without driving the photographing lens 3. G: If tracking determination 1 is NO, tracking determination 2 is NO, focus determination 2 is NO, and focus determination 3 is YES, lens drive 1 (normal drive) is performed to maintain the current priority state.

H: When the tracking determination 1 is NO, the tracking determination 2 is NO, the focusing determination 2 is NO, and the focusing determination 3 is NO, first, the currently selected defocus amount is changed from dn = pn to dn = Change to rn. Then, lens drive 1 (normal drive) is performed to shift from the current priority state to the closest state. I: When the tracking determination 1 is YES or the tracking determination 2 is YES, when the tracking determination 2 is YES, the currently selected defocus amount dn = p so as not to cause any trouble in transition to the tracking state.
n to dn = sn, and the image plane speed V (n-1) n = Vp (n
-1) n is rewritten to V (n-1) n = Vs (n-1) n. Then, lens drive 2 (tracking drive) is performed to shift from the current priority state to the tracking state. J: If the tracking determination 1 is YES, lens driving 2 (tracking driving) is performed to maintain the tracking state. K: If the tracking determination 1 is NO, change the currently selected defocus amount dn = pn to dn = rn. Then, lens driving 1 (normal driving) is performed to shift from the tracking state to the closest state. N: When the tracking determination 2 is NO and the focusing determination 4 is YES, the photographing lens 3 is not driven, and the focus shifts from the current priority state to the focusing focus locked state. P: If the tracking determination 1 is YES or the tracking determination 2 is YES, the current selected defocus amount dn = pn is set to dn = sn and the image plane speed V (n -1) n = Vp (n-1) n to V (n-1) n
= Vs (n-1) n. Then, the lens drive 2 (tracking drive) is performed to shift from the focus locked state to the tracking state. Q: When tracking determination 1 is NO and tracking determination 2 is NO,
The photographing lens 3 is not driven, and the focus lock state is maintained.

FIGS. 15 and 16 are flowcharts showing examples of the focus adjustment control program in the single mode. In this operation, in addition to the operation in the continuous mode shown in FIGS. 11 and 12, a focus determination and a focus lock state in the current priority state are added. Steps for performing the same processes as those in FIGS. 11 and 12 are denoted by the same step numbers, and differences will be mainly described. [Current priority state] In step S113, in-focus determination 2 is performed. If the determination is affirmative, the process proceeds to step S116. If the determination is negative, the process proceeds to step S114. In step S116, focus determination 4 is performed. If the determination is affirmative, the process proceeds to step S130 (transition to the focus locked state). If the determination is negative, the process returns to step S110. [Focus focus lock state] In step S130, focus detection 2 is performed, and in step S131, tracking determination 1 is performed. If affirmed, the process proceeds to step S120 (transition to the tracking state), and if denied, the process proceeds to step S132. In step S132, tracking determination 2 is performed, and if affirmative, the process proceeds to step S120 (transition to a tracking state).
Note that the selected defocus amount dn = sn, and the image plane speed V (n
-1) n = Vs (n-1) n. Step S
If the result in 132 is negative, the process returns to step S130.

As described above, in the focus determination 4 in the current priority state, the focus shifts to the in-focus focus lock state and the lens driving is prohibited when the in-focus state is continued several times. No locking action is required. In addition, even in the in-focus focus lock state, the still movement of the subject is detected, so that even when the still subject moves, the detection can be reliably performed, and the lens drive prohibition can be canceled and the lens drive can be resumed. it can.

FIGS. 17 and 18 are flowcharts showing another example of the control program in the single mode. FIG.
5, only the operation in the single mode shown in FIG. 16 is different from that in the in-focus focus locked state. Steps for performing the same processing are denoted by the same step numbers, and the differences will be mainly described. [Current priority state] In step S116, focus determination 4 is performed, and if affirmative, the process proceeds to step S133 (transition to a focus lock state), and if negative, step SS1.
Return to 10. [In-focus focus locked state] In step S133, motion detection is performed. This motion detection is performed by the AFCPU 1 based on an output signal from the motion detection device 14. As a result of the judgment,
If the photographing lens 3 or the body is moving (there is blurring), the process returns to step S133 without performing tracking determination. Otherwise, the process proceeds to step S130 to perform tracking determination. In step S132, tracking determination 2 is performed, and if affirmative, the process proceeds to step S120 (transition to a tracking state). Selected defocus amount dn = sn, image plane speed V (n-1) n =
Vs (n-1) n. When step S132 is denied, the process returns to step S133.

As described above, in the in-focus focus locked state, as a result of detecting the movement of the photographing lens 3 or the body, the tracking determination is prohibited when the camera is moving, and the tracking determination is performed when the camera is not moving. In addition, when the camera is panned, the distance relationship with the subject changes, so that the tracking operation is not performed by erroneously determining that the subject is moving, and when the camera is still, the subject is securely stopped. A determination of movement can be made. In the closest state, the current priority state, and the tracking state, the tracking determination,
The motion detection may be performed before the focus determination, and the tracking determination or the focus determination may be prohibited when the photographing lens or the body is moving, and the tracking determination or the focus determination may be permitted only when the shooting lens or the body is not moving. . In this way, when the camera is panned, the distance relationship with the subject changes, and it is determined that the subject is erroneously moving and a tracking operation is performed,
In addition to eliminating focus determination for an unnecessary subject, when the camera is stationary, it is possible to reliably determine the still movement of the subject and to determine the focus.

FIGS. 19 and 20 are flowcharts showing another example of the control program in the continuous mode. In this continuous mode, FIG.
1 is different from the continuous mode shown in FIG. 12 only in that the operation of setting the frame speed in the closest state and the tracking state is added. Steps for performing the same processing are denoted by the same step numbers. The following description focuses on the differences. [Non-operating state] In step S101, when the half-press signal is ON, the process proceeds to step S106 (transition to the closest state). [Nearest state] In step S106, frame speed setting 1 is performed, and the process proceeds to step S102. In the frame speed setting 1, a frame speed for a still subject during continuous shooting is set, and the set frame speed is sent from the AF CPU 1 to the main CPU 2 by an A signal. The main CPU 2 calculates the frame speed based on the transmitted frame speed.
When the continuous shooting mode is designated by the frame speed setting unit 21, the frame speed when a full-press signal is input is controlled. Step S
At 105, lens driving 1 is performed, and the process returns to step S106. Steps S103, S111, S112, S
When the tracking determination in each state of 122 is affirmed, the process proceeds to step S123. [Tracking state] In step S123, frame speed setting 2 is performed.
Proceed to step S120. In the frame speed setting 2, a frame speed (higher than the frame speed of the frame speed setting 1) with respect to a moving subject during continuous shooting is set, and the set frame speed is set to AFCP by the A signal.
It is sent from U1 to the main CPU2. Main CPU2
Controls the frame speed when the full-press signal is input when the continuous shooting mode is designated by the frame speed setting unit 21 based on the transmitted frame speed.

As described above, when it is determined that the subject is stationary and moving, when the subject is moving, the frame speed is automatically switched to the high frame speed. Becomes better. Note that the frame speed for a still subject may be the frame speed set by the frame speed setting unit 21. Further, the frame speeds set in the frame speed settings 1 and 2 may be set in advance from outside.

FIG. 21 is a flowchart showing a modified example of the control program shown in FIGS. FIG.
20 is different from FIG. 20 in the frame speed setting operation in the tracking state. Steps S200 and S2 are performed instead of step S123 in FIG.
01 is added. Steps S103, S111, S1
When the tracking determination in each of the states 12 and S122 is affirmed, the process proceeds to step S200. [Tracking state] In step S200, distance detection is performed by the distance detection device 31, and information on the subject distance X corresponding to the current position of the photographing lens 3 is captured. Subsequent step S2
At 01, the frame speed setting 3 is performed. In the frame speed setting 3, a frame speed Y for a moving subject during continuous shooting is set based on the subject distance X, and the set frame speed is sent from the AF CPU 1 to the main CPU 2 by an A signal. The main CPU 2 controls the frame speed when a full-press signal is input when the continuous shooting mode is designated by the frame speed setting unit 21 based on the transmitted frame speed. The relationship between the subject distance X and the frame speed Y is set so that when the subject distance is short, the speed is higher than when the subject distance is long. Example 1: Y = Y1 if X> Xk, Y = Y2 if X ≦ Xk, where Xk is a predetermined distance, Y1 and Y2 are predetermined frame speeds, Y1
<Y2. Example 2: Y = Kx / X Here, Kx is a predetermined value.

As described above, when the subject is moving,
Since the frame speed is automatically switched in accordance with the subject distance, the photographer does not need to manually switch the frame speed, thereby improving the operability. In the first and second examples, the predetermined distance Xk, the frame speeds Y1 and Y2, and the predetermined value Kx may be set in advance from outside.

FIG. 22 is a flowchart showing a modification of the control program shown in FIGS. FIG.
Instead of step S123 in FIG. 20, the following step S2
00, S202, S203, and S204 are added. If the tracking determination in each state of steps S103, S111, S112, and S122 is affirmed, the process proceeds to step S20.
Go to 0. [Tracking state] In step S200, distance detection is performed, and information on the subject distance X corresponding to the current position of the photographing lens 3 is fetched from the distance detection device 31. Subsequent step S202
Then, the focal length detection is performed, and information on the current focal length Z of the photographing lens 3 is taken in from the focal length detecting device 32. In step S203, the current magnification W of the photographing lens 3 is calculated based on the subject distance X and the focal length Z. W = Z / X (19) In step S204, frame speed setting 4 is performed. In the frame speed setting 4, the frame speed Y for the moving subject during continuous shooting is set based on the shooting magnification W, and the set frame speed is set to the AF signal by the A signal.
Sent from CPU 1 to main CPU 2. Main CPU
Reference numeral 2 controls the frame speed when a full-press signal is input when the continuous shooting mode is designated by the frame speed setting unit 21 based on the transmitted frame speed. The relationship between the shooting magnification W and the frame speed Y is
When the magnification is high, the speed is set higher than when the magnification is low. Example 1: Y = Y3 if W> Wk, Y = Y4 if W ≦ Wk, where Wk is a predetermined magnification, Y3 and Y4 are predetermined frame speeds, Y4
<Y3. Example 2: Y = Kw / W Here, Kw is a predetermined value.

As described above, when the subject is moving, the frame speed is automatically switched in accordance with the photographing magnification, so that the photographer does not need to manually switch the frame speed, and the operability is improved. . In the first and second examples, the predetermined distance Wk, the frame speeds Y3, Y4, and the predetermined value Kw may be set in advance from outside.

FIGS. 23 and 24 are flowcharts showing another example of the control program in the continuous mode. Only the operation in the tracking mode is different from the continuous mode shown in FIGS. 11 and 12, and the steps for performing the same processing are denoted by the same step numbers and the differences will be mainly described. Steps S103, S111, S11
When the tracking determination in each of the states S2 and S122 is affirmed, the process proceeds to step S200. [Tracking state] In step S200, distance detection is performed, and information on the subject distance X corresponding to the current position of the photographing lens 3 is fetched from the distance detection device 31. In subsequent S202, the focal length is detected, and information on the current focal length Z of the photographing lens 3 is fetched from the focal length detecting device 32. Step S2
At 05, speed detection is performed. First, the current magnification W of the photographing lens 3 is calculated based on the subject distance X and the focal length Z. W = Z / X (20) Next, the subject speed S is calculated using the image plane speed V (n-1) n at the time of the latest tracking determination that movement has been determined. S = V (n-1) n / W ² (21) In step S206, time prediction 1 is performed. From the distance Xm set in the distance setting described later, the current subject distance X, and the subject speed S, a time T1 to reach the distance Xm from the current time is predicted. T1 = (X−Xm) / S (22) The time T1 may be determined in consideration of the time lag Tr from the start of exposure to the start of actual exposure. T1 = (X−Xm) / S−Tr (23) In step S207, the time T1 predicted by the time prediction 1
On the timer and start.

FIG. 25 is a flowchart showing a distance setting interrupt operation. In step S300, interrupt 1 is activated. Interrupt 1 is generated by a setting operation of distance setting device 11. In the following step S301, distance setting is performed, and the distance Xm set by the distance setting device 11 is read. In step S302, the process returns from the interrupt 1.

FIG. 26 is a flowchart showing the timer interrupt operation. In step S400, interrupt 2 is activated. Interrupt 2 occurs at the end of counting the time set in the timer. Subsequent step S401
Activate exposure control. In the exposure control activation, information of the exposure control activation request is sent from the AF CPU 1 to the main CPU 2 by the A signal. The main CPU 2 starts the exposure control based on the information of the transmitted exposure control activation request. In step S402, the process returns from interrupt 2.

As described above, when the subject is moving,
Since the exposure is performed when the subject reaches the preset distance, the photographer does not need to manually release the image by relying on intuition, and can accurately photograph the moving subject at a desired distance.

FIGS. 27 and 28 are flowcharts showing modified examples of the control program shown in FIGS.
Note that only the operation in the tracking state and the magnification setting operation are different from those in FIGS. 23 to 25, and only different parts will be described. FIG.
7 is an operation in a tracking state. Time prediction 2 is performed instead of time prediction 1. In step S205 in FIG. 24, speed detection is performed. First, the current magnification W of the photographing lens 3 is calculated based on the subject distance X and the focal length Z. W = Z / X (24) Next, the subject speed S is calculated using the image plane speed V (n-1) n at the time of the latest tracking determination that movement has been determined. S = V (n-1) n / W ² (25) In step S208, time prediction 2 is performed. A subject distance Xw at the time when the magnification becomes Wm is obtained based on the magnification Wm set in the magnification setting described later and the current focal length Z. Xw = Z / Wm (26) Then, a time T1 to reach the distance Xm from the current time is predicted from the subject distance Xw, the current subject distance X, and the subject speed S. T1 = (X−Xw) / S (27) The time T1 may be determined in consideration of the time lag Tr from the start of exposure to the start of actual exposure. T1 = (X−Xw) / S−Tr (28) In step S207, the time T2 predicted by the time prediction 2
Set to the timer and start.

FIG. 28 is a flowchart showing an interrupt operation for setting a magnification. In step S500, interrupt 3 is activated. The interrupt 3 is generated by a setting operation of the magnification setting device 12. In step S501, a magnification is set, and the magnification Wm set by the magnification setting unit 12 is read. In step S502, the process returns from the interrupt 3. As described above, when the subject is moving, the exposure is performed when the subject reaches the preset magnification, so that the photographer does not need to rely on intuition to release the image, and can perform accurate shooting. Is improved. Note that FIG.
In the embodiments of FIGS. 24 and 27, the time lag Tr may be set in advance from outside. Further, after the exposure control is activated once, continuous shooting may be performed.

In the configuration of the above embodiment, the AF
The sensor 13 and the AF CPU 1 serve as a focus detection unit.
CPU1 is a first movement determination unit, a second movement determination unit,
Control means, image surface speed calculation means, image surface speed prediction means and
The motor 15 constitutes lens drive control means , and the motor 15 constitutes lens drive means.

[0065]

As described above, according to the first aspect of the present invention, the present invention is applicable to both the closest state and the current priority state.
It is possible to judge a sharp movement of the subject, and it is possible to perform a stable and responsive automatic focus adjustment operation. Claim 2
According to the invention, it is possible to stabilize the drive control of the Utsushitai tracking. According to the third aspect of the present invention, a series of image plane speeds is obtained.
Highest continuity, that is, the same from past to present
The focus detection area that is most likely to capture the subject
Since you have to select the defocus amount, each focus detection
The image speed of the subject in the area can be determined accurately,
The drive control for body tracking can be further stabilized.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims.

FIG. 2 is a diagram corresponding to claims.

FIG. 3 is a diagram corresponding to claims.

FIG. 4 is a block diagram showing a configuration of one embodiment.

FIG. 5 is a diagram showing a configuration example of an AF sensor.

FIG. 6 is a diagram showing a setting example of a focus detection area in a shooting screen.

FIG. 7 is a diagram showing another example of setting a focus detection area in a shooting screen.

FIG. 8 is a diagram showing the movement of an ideal image plane of a moving subject and the movement of the imaging plane of the taking lens when the taking lens is driven to track the moving subject.

FIG. 9 is a diagram showing a transition of an operation state in a continuous mode.

FIG. 10 is a diagram showing a transition of an operation state in a single mode.

FIG. 11 is a flowchart showing an example of a focus adjustment control program in a continuous mode.

FIG. 12 is a flowchart illustrating an example of a focus adjustment control program in a continuous mode.

FIG. 13 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

FIG. 14 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

FIG. 15 is a flowchart illustrating an example of a focus adjustment control program in a single mode.

FIG. 16 is a flowchart illustrating an example of a focus adjustment control program in a single mode.

FIG. 17 is a flowchart showing another example of the focus adjustment control program in the single mode.

FIG. 18 is a flowchart showing another example of the focus adjustment control program in the single mode.

FIG. 19 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

FIG. 20 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

FIG. 21 is a flowchart illustrating another example of a focus adjustment control program in the continuous mode.

FIG. 22 is a flowchart illustrating another example of a focus adjustment control program in the continuous mode.

FIG. 23 is a flowchart illustrating another example of a focus adjustment control program in the continuous mode.

FIG. 24 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

FIG. 25 is a flowchart showing a distance setting interrupt program.

FIG. 26 is a flowchart showing a timer interrupt program.

FIG. 27 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

FIG. 28 is a flowchart showing another example of the focus adjustment control program in the continuous mode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 AFCPU 2 Main CPU 3 Photographing lens 11 Distance setting device 12 Magnification setting device 13 AF sensor 14 Motion detecting device 15 Motor 20 Release button 21 Frame speed setting device 22 Shutter mechanism 23 Winding device 24 Shutter charging mechanism 25 Mirror mechanism 31 Distance detector 32 Focal length detector 33 Aperture mechanism

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-317016 (JP, A) JP-A-4-278907 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 7/28-7/40

Claims (3)

(57) [Claims] 1. A focus detecting means for repeatedly detecting a plurality of defocus amounts in a plurality of focus detection areas set in a photographing screen, and a defocus indicating the closest of the plurality of defocus amounts.
The photographing lens is driven by the lens driving means based on the amount of waste.
In the closest moving state, the default
The determination of the movement of the subject based on the time change of the scrap amount
One movement determination means, and a differential indicating the minimum absolute value of the plurality of defocus amounts.
The photographing level is determined by the lens driving means based on the amount of focus.
In the current priority state for driving the lens, the absolute value
Of the subject based on the temporal change of the defocus amount
The subject is moved by the second movement judging means for judging the movement and the first or second movement judging means.
If it is determined that the
A subject for tracking a moving subject based on the amount of focus
Calculate the image plane speed of the body, and based on this object image plane speed
The photographing lens is driven by the lens driving means.
Tracking from the closest state or the current priority state
An automatic focusing camera, comprising: a control unit for shifting to a state . 2. A shooting focus detecting means repeatedly detects a plurality of defocus amounts at a plurality of focus detection areas set in the shadow screen, said plurality of defocus amounts, the at past focus detection
One defocuser selected from multiple defocus amounts
The plurality of focus detection areas,
Image plane speed calculation means for calculating the image plane speed of the body, and corresponds to one defocus amount selected at the time of past focus detection
Of the current focus detection area
An image plane speed estimating means for calculating a imaginary object image plane speed; and an object image surface speed calculated in the plurality of focus detection areas.
The object image surface speed closest to the expected object image surface speed from the middle
Select the degree of movement, and based on the selected
Lens drive control that drives the taking lens to track the object
Automatic focusing camera comprising: a means. 3. The automatic focusing camera according to claim 2,
And the image plane speed calculating means calculates the defocus amount of the plurality of defocus amounts.
The object image surface speed closest to the expected object image surface speed from the middle
An automatic focusing camera , wherein a defocus amount of a focus detection area indicating a degree is selected .