JPH05188271A - Photographic device with anamorphic system - Google Patents

Abstract

PURPOSE:To obtain the photographic device with the anamorphic system which can obtain in-focus image information of good picture quality even if a subject distance varies when a photograph is taken while the anamorphic system is mounted in front of a main photography system. CONSTITUTION:This photographic device has anamorphic system 101 and master lenses 102 and when a focusing state is obtained by controlling the position of the anamorphic lens 1 for focusing in the anamorphic system 101 on the optical axis by a control means 15 according to the position of the axis of the focusing lens 6 in the master lenses 102, the control means 15 confirms whether or not both the lenses 1 and 6 are at specific positions according to the signals from position detecting means 9 and 13 which detects the position of the focusing lens 6 and the position of the anamorphic lens 1 and control focusing operation according to the confirmation result.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographing device having an anamorphic system, and is particularly suitable for compressing image information in a horizontal direction or a vertical direction by using the anamorphic system and recording it as a compressed image on a recording medium surface. It is something.

[0002]

2. Description of the Related Art Conventionally, an anamorphic system (anamorphic converter) is mounted in front of a main photographing system (master lens) to compress image information in a horizontal direction or a vertical direction and record it on a recording medium surface. There have been proposed various photographing devices for viewing widened images.

FIG. 8 shows a state in which a conventional anamorphic converter 81 is arranged in front of the main photographing system 82. FIG. 8A shows a horizontal image formation in which the anamorphic converter 81 has a refractive power. FIG. 8B is an optical path diagram showing a vertical image formation in which the anamorphic converter 81 has no refracting power.

Due to the action of the anamorphic converter 81, a compressed image is photographed in a state where the vertical image forming magnification and the horizontal image forming magnification are different. When an anamorphic converter is used, it is necessary to match the image formation points in the vertical and horizontal directions when focusing.

Next, description will be given of a case where the object moves from a state where the focus is simultaneously in the vertical and horizontal directions in FIG.

FIG. 9 (A) is an optical path diagram showing a horizontal image formation in which the anamorphic converter 81 has a refracting power, and FIG. 9 (B) shows a vertical connection in which the anamorphic converter 81 does not have a refracting power. It is an optical-path figure which shows an image.

When the object position with respect to the main photographing system 82 is defined as a secondary object point, when the object is simply moved, the secondary object point O'for horizontal imaging and the secondary object point for vertical imaging. O ″ causes a shift ΔO in the optical axis direction of the main photographing system 82.

The deviation of the secondary object point O "with respect to the image formation in the direction perpendicular to the object position O is due to the action of the anamorphic converter 81 as a parallel plate. The thickness on the optical axis of the anamorphic converter is irrelevant to the refractive power. It is determined by the shift effect.

On the other hand, the object position O and the horizontal image formation 2
The deviation of the next object point O'is due to the anamorphic converter 81.
Affected by the refractive power of.

Since the positions of the secondary object points O'and O "with respect to the main photographing system are different from each other, the horizontal image forming point I'and the vertical image forming point I" do not coincide with each other, resulting in a shift .DELTA.I. Therefore, if only the focusing of the main shooting system has the focus adjusting function,
The focus can be adjusted either horizontally or vertically, but not horizontally and vertically at the same time.

In order to solve such a problem, for example, Japanese Patent Publication No. 48-24048 discloses focusing in the vertical direction by focusing of the main photographing system, while moving in the horizontal direction by moving a part of the anamorphic converter. The focal points in both horizontal and vertical directions are matched.

FIG. 10A shows this state.
The convex cylindrical lens 81P forming the anamorphic converter 81 is moved in the optical axis direction as indicated by the arrow to adjust the horizontal image forming position.

On the other hand, as shown in FIG. 10B, since the anamorphic converter 81 only functions as a parallel plate in vertical image formation, the vertical image formation position does not change even if the convex cylindrical lens 81P is moved. Is.
By moving the anamorphic converter, you can independently control only the horizontal image formation,
It is possible to match the image forming positions in both the horizontal and vertical directions.

In JP-B-48-24048, an integrated type in which a focusing mechanism of a main photographing system and a focusing mechanism of an anamorphic converter are mechanically interlocked with each other while photographing is always made to match the focal positions in the horizontal direction and the vertical direction Are proposing things.

On the other hand, Japanese Patent Laid-Open No. 25407/1993 proposes a method for focusing in the horizontal and vertical directions by interlocking the lens used for focusing in the anamorphic converter based on the position of the focusing lens in the main photographing system. Has been done.

[0016]

Generally, in many cases, an anamorphic system is mounted as a converter in front of the master lens (on the object side) for photographing. In such a case, the outer diameter of the anamorphic system becomes larger than the outer diameter of the front group of the master lens, and the weight also becomes larger.

Therefore, when the focusing lens in the master lens and the anamorphic lens for focusing in the anamorphic system are made to cooperate in the focusing operation, the driving speed of the anamorphic lens is compared with the driving speed of the focusing lens. And it will be late.

Therefore, for example, the focus operation of the anamorphic lens cannot follow the focus operation of the focusing lens with respect to the variation of the subject distance, which causes the focus shift due to the variation of the subject distance and the inappropriate lens arrangement. There is a problem in that a focus shift occurs and accurate focus operation cannot be performed.

The present invention attaches an anamorphic system in front of the main photographing system (master lens) to compress the image information in the horizontal direction or the vertical direction and photograph the image by focusing the focusing lens of the main photographing system and the anamorphic system. An object of the present invention is to provide a photographing apparatus having an anamorphic system capable of performing accurate focus operation and obtaining image information of good optical performance by appropriately controlling driving of an anamorphic lens for focusing.

[0020]

An image pickup apparatus having an anamorphic system according to the present invention has an anamorphic system having different refracting powers in a horizontal direction and a vertical direction, and a master lens,
The position on the optical axis of the focusing lens in the master lens and the focusing anamorphic of the anamorphic system based on the position on the optical axis is drive-controlled by the control means to obtain the focused state. At this time, the control means confirms whether or not both lenses are located at predetermined positions based on a signal from the position detection means for detecting the position of the focusing lens and the position of the anamorphic lens, and based on that, It is characterized in that the focusing operation is controlled by the above.

In particular, the present invention is characterized in that the control means suspends the focusing operation until it is confirmed that the focusing lens and the anamorphic lens are located at predetermined positions on the optical axis.

[0022]

Embodiment 1 FIG. 1 is a schematic view of the essential portions of Embodiment 1 of the present invention.

In the figure, 101 is an anamorphic system, which is an anamorphic lens 1 composed of an anamorphic lens 1 composed of a cylindrical lens of negative refractive power for focusing which moves on the optical axis at the time of focusing and a cylindrical lens of fixed positive refractive power. 2 and.

Reference numeral 102 denotes a main photographing system (master lens), which comprises a rear focus type zoom lens. The main photographing system 102 is a lens group 3 having a fixed positive refractive power,
A variable power part (variator lens) 4 for variable power, a fixed lens group 5, and a lens group 6 having a correction function and a focus function for correcting image plane variable power associated with the variable power (hereinafter referred to as “focus lens 6”). (Referred to)).

That is, the main photographing system 102 of this embodiment is composed of a rear focus type zoom lens in which focusing is performed by the lens 6 on the image plane side of the variable power unit 4.

Therefore, as will be described later, the amount of movement of the focusing lens differs depending on the zoom position, that is, the difference in focal length, even for the same object distance, and the amount of movement is a two o'clock curve or discontinuously. Will change.

Reference numeral 7 denotes an image pickup device, which is composed of a CCD. Reference numerals 8, 10, 12 denote motors as driving means. The motor 8 uses the anamorphic lens 1 and the motor 10
Is driving the variable power unit 4 and the motor 12 is driving the focusing lens 6 on the optical axis.

Reference numerals 9, 11, and 13 are encoders as position detecting means. The encoder 9 is the anamorphic lens 1, the encoder 11 is the variable power unit 4, the encoder 1
Reference numeral 3 respectively detects the position of the focusing lens on the optical axis.

Reference numeral 14 denotes an automatic focus detection circuit (AF circuit) which detects the focus state (focus state) of the main photographing system 102 using the image signal obtained from the photographing element 7. Reference numeral 15 is a control means, which controls various operations when driving each lens.

Reference numeral 16 denotes a storage means, which is a data table D
It has A1 and a data table DA2. As will be described later, the data table DA1 drives a focusing lens 6 which acts as a compensator and a focus for varying the magnification from a position on the optical axis of the magnification varying unit 4 (hereinafter referred to as "position"). Position information for each object distance for control is stored.

As will be described later, the data table DA2 stores position information for obtaining the position of the anamorphic lens 1 with respect to the position of the variable power unit 4 and the position of the focusing lens 6.

In the present embodiment, the positional relationship on the optical axis between the variable power unit 4 of the main photographing system 102 and the focusing lens 6 is shown in FIG.
Is shown in.

In FIG. 6, the horizontal axis indicates the zoom position, that is, the position on the optical axis of the variable power unit 4, and the vertical axis indicates the focusing lens 6 which functions as a compensator for correcting the image plane variation due to the variable power. The position on the optical axis is shown. Each curve shows the object distance. W indicates the zoom position at the wide-angle end, and T indicates the zoom position at the telephoto end.

In the figure, for example, when the object distance is infinity, the focusing lens 6 is moved along with the movement of the variable power unit 4 on the optical axis due to the variable power.
Moves on the curve 61. In order to control the movement of the focusing lens 6 at this time, it is necessary to specify the position of the focusing lens on the optical axis according to the variable power unit 4. Further, the position of the focusing lens at a certain object distance varies depending on the position of the variable power portion. In order to control it, movement information of the focusing lens according to the position of the variable power portion is needed.

Therefore, the data table DA1 stores position information for controlling the movement of the focusing lens 6, that is, the position on the optical axis from the position of the variable power unit 4 at this time.

On the other hand, the position of the anamorphic lens 1 with respect to the object distance (subject distance) is as shown in FIG. 7, for example. The data table DA2 stores position information such as the curve 71 of the anamorphic lens 1 with respect to the object distance converted from both the position of the variable power unit 4 and the position of the focusing lens 6.

Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

In this embodiment, when the power is turned on, the control means 15 sets the variable power unit 4, the focusing lens 6 and the anamorphic lens 1 to a predetermined initial position so that the photographing is possible. When out-of-focus is recognized in the focus information obtained from the AF circuit 14 in the image-capable state, that is, when the focus is out of focus, the control unit 15 activates the focus. Then, it is determined whether or not the scaling unit 4 is moving, that is, whether or not it is scaling. If it is moving, the scaling unit 4 stops moving and the position of the scaling unit 4 is detected by the encoder 11. Then, the focusing lens 6 is moved on the optical axis by the motor 12 while referring to the data table DA1, and the position of the focusing lens 6 after the movement is detected by the encoder 13.

Then, the position of the anamorphic lens 1 is determined by referring to the data table DA2 from the detected positions of the variable power unit 4 and the focusing lens 6, and the anamorphic lens 1 is moved to a predetermined position by the motor 8. At this time, the position of the anamorphic lens 1 is detected by the encoder 9, and it is confirmed whether or not the detected position of the anamorphic lens 1 matches the position previously determined from the data table DA2. At this time, the control means 15 stops the focus operation until they match. When it is determined that they match, the movement of the variable power unit 4 is restarted.

As described above, in this embodiment, the control unit 15 stops the next operation until the focusing lens 6 and the anamorphic lens 1 are located at the predetermined positions on the optical axis. This allows the anamorphic lens 1 and the focusing lens 6 to move while always maintaining a predetermined relationship.

In the present embodiment, when the AF circuit 14 detects out-of-focus, when the variable power unit 4 is moving,
Instead of stopping the variable power unit 4, the moving speed may be reduced to a moving speed that takes into account the time required to adjust the position of the anamorphic lens 1 of the variable power unit 4.

In this embodiment, as described above, the anamorphic lens 1 and the focusing lens 6 are driven in conjunction with each other, so that the vertical and horizontal in-focus states of the image information coincide with each other.

Further, in this embodiment, an automatic focus detection system is realized by adding the focus information from the AF circuit 14 to such an operation.

3 and 4 are schematic views of the essential portions of Embodiments 2 and 3 of the present invention.

In Examples 2 and 3, the anamorphic system 101 was used.
1 is used as an anamorphic converter that is detachably attached to the front of the main imaging system 102, and other configurations are basically the same as those of the first embodiment in FIG. 3 and 4, the same elements as those shown in FIG. 1 are designated by the same reference numerals.

The second embodiment shown in FIG. 3 differs from the first embodiment shown in FIG. 1 in that a control means 18 is newly provided in the anamorphic system 101.

In FIG. 3, reference numeral 17 denotes a connecting portion, which transmits and receives the various signals as described above between the control means 15 of the main photographing system 102 and the encoder 9 or the control means 18 of the anamorphic system 101 via the connecting portion 17. It is carried out. The control unit 18 drives and controls the anamorphic lens 1 via the connection unit 17 based on a signal from the control unit 15.

In this embodiment, the control circuit 18 controls the drive of the anamorphic lens 1 by the motor 8.
By performing data communication via the connection unit 17,
The same operation as that of the first embodiment is realized.

In the third embodiment shown in FIG. 4, as compared with the first embodiment shown in FIG. 1, a data table DA2 for controlling the driving of the anamorphic lens 1 is provided to the anamorphic system 101 and the main photographing system 10 is provided.
The difference is that it moved from 2 to anamorphic system 101.

In the third embodiment, the control means 15 has the connecting portion 1
Data table 1 of anamorphic system 101 through 7
9, the anamorphic lens 1 is drive-controlled.

Next, the operation of the third embodiment will be described with reference to the flowchart of FIG.

In this embodiment, when the power is turned on, the control means 15 determines whether or not the anamorphic system is attached to the master lens 102. Then, when it is attached, the anamorphic mode is set, and the variable power unit 4 and the focusing lens 6 are set to a predetermined initial position so that the photographing is possible. When out-of-focus is detected in the focus information detected by the AF circuit 14 in the image-capable state, the control unit 15 activates the focus. Normal focus is performed when not in anamorphic mode, but when in anamorphic mode, it is determined whether or not the scaling unit 4 is moving, that is, whether or not scaling is in progress. If it is moving, the scaling unit 4 is moved. Slow down.

Then, the position of the variable power unit 4 is set by the encoder 11
Then, the focusing lens 6 is moved by the motor 12 while referring to the data table DA1. Then, the position of the focusing lens after the movement is detected by the encoder 13, and the position of the anamorphic lens 1 is determined by referring to the data table 19 from the detected positions of the zooming unit 4 and the focusing lens 6 to determine the position of the anamorphic lens. 1 is moved to a predetermined position by the motor 8.

Then, the position of the anamorphic lens 1 is detected by the encoder 9, and it is confirmed whether or not the detected position of the anamorphic lens 1 matches the position previously determined from the data table 19.

Then, the control means 15 stops the next operation until they match. When it is confirmed that they match, the moving speed of the variable power unit 4 is returned to the normal speed, and the focus operation is completed. As a result, the anamorphic lens 1 and the focusing lens 6 always move while maintaining the predetermined relationship.

In this embodiment, since the data for determining the position of the anamorphic lens 1 is provided in the anamorphic system 101, the anamorphic converters having different anamorphic ratios can be controlled by the same control means. is doing.

[0057]

According to the present invention, as described above, when the anamorphic system is mounted in front of the main photographing system (master lens) and the image information is compressed in the horizontal or vertical direction, the main photographing system By appropriately controlling the driving of the focusing lens and the anamorphic lens for focusing the anamorphic system, an anamorphic system capable of performing accurate focusing operation even on a moving subject and obtaining image information of good optical performance. It is possible to achieve an image pickup apparatus having.

[Brief description of drawings]

FIG. 1 is a schematic view of a main part of a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of FIG.

FIG. 3 is a schematic view of the essential portions of Embodiment 2 of the present invention.

FIG. 4 is a schematic view of the essential portions of Embodiment 3 of the present invention.

5 is a flow chart showing the operation of FIG.

FIG. 6 is an explanatory view showing a positional relationship between a variable power portion and a focusing lens of the rear focus type zoom lens according to the present invention.

FIG. 7 is an explanatory diagram showing a relationship between an anamorphic lens according to the present invention and a subject distance.

FIG. 8 is an explanatory diagram showing the image forming action of the anamorphic lens.

FIG. 9 is an explanatory diagram showing matching of image forming positions in the horizontal and vertical directions due to a change in subject distance.

FIG. 10 is an explanatory diagram showing correction of the state of FIG. 9 and matching of image forming positions in the horizontal and vertical directions.

[Explanation of symbols]

 101 Anamorphic system 102 Main photographing system (master lens) 4 Magnifying unit 6 Focusing lens 8, 10, 12 Driving means 9, 11, 13 Position detecting means 15, 18 Control means 16, 19 Storage means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Kimura Inventor Kenichi Kimura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (3)

[Claims] 1. A anamorphic system having different refracting powers in a horizontal direction and a vertical direction, and a master lens, wherein a focusing lens in the master lens and a position on the optical axis of the anamorphic system The position detecting means for detecting the position of the focusing lens and the position of the anamorphic lens when the control means drives and controls the position on the optical axis with the anamorphic for focusing An imaging device having an anamorphic system, characterized in that it is confirmed whether or not both lenses are located at a predetermined position based on a signal from, and the focusing operation is controlled based on that. 2. The anamorphic anamorphic device according to claim 1, wherein the control means suspends the focusing operation until it is confirmed that the focusing lens and the anamorphic lens are located at predetermined positions on the optical axis. An imaging device with a system. 3. The focusing unit and the anamorphic lens are controlled by the control unit using position information from a storage unit that stores a positional relationship between the variable power unit, the focusing lens, and the anamorphic lens on the optical axis. The photographic device having an anamorphic system according to claim 1, wherein it is confirmed whether or not is located at a predetermined position.