JP4402206B2 - Lens device and camera system - Google Patents

Description

また、同様に、ズーム位置およびフォーカス位置がＰｚｉ’とＦｐの時の画角（ωｏｒｇ’’）を次式を用いて直線近似により算出する。
【００３４】

次に、求めた上記２つの画角を用いて、ズーム位置およびフォーカス位置がＺｐとＦｐのときの画角、つまり基準画角（ωｏｒｇ）を次式を用いて直線近似により算出する。
【００３５】

要するに、ステップ３２では、画角データωｉｊを代表とし、相互に隣接する４分割点の画角データ（ωｉｊ，ωｉｊ’，ωｉ’ｊ，ωｉ’ｊ’）のうち同一ズーム位置Ｐｚｉに対する２点ごとの画角データ（ωｉｊとωｉｊ’，ωｉ’ｊとωｉ’ｊ’）をそれぞれ補間するフォーカス位置Ｆｐに対する２つの画角直線近似データ（ωｏｒｇ’，ωｏｒｇ’’）を直線近似により算出し、さらに、これら２つの画角直線近似データ（ωｏｒｇ’，ωｏｒｇ’’）を補間するズーム位置Ｚｐに対する画角直線近似データωｏｒｇを算出して、これを基準画角として決定する。こうして、基準画角を決定すると、ステップ３３に進み、処理を終了する。
【００３６】
次に、図２のステップ２４にて行われる画角補正処理について、図５のフローを用いて説明する。まず、フォーカスレンズ１０が動いた後の位置を位置検出器１１を通して検出すると、そのフォーカス位置（Ｆｐ）が、フォーカスのｊ番目の分割点（Ｐｆｊ）とｊ＋１番目の分割点（Ｐｆｊ’）との間になるようＰｆｊを決定する（ステップ４１）。
【００３７】
次に、このＰｆｊを基準に、上述した式を用い、ｉを０からｎまで変化させてデータとしての画角ωｏｒｇ’とωｏｒｇ’’を計算し、基準画角ωｏｒｇがこれら画角ωｏｒｇ’，ωｏｒｇ’’の間に入るようなｉを見つけ、４点の画角データの代表となるωｉｊを決定する（ステップ４２）。
【００３８】
次に、画角およびフォーカス位置がωｏｒｇとＦｐのときのズーム指令位置Ｚｃを次式を用いて直線近似により算出する（ステップ４３）。
【００３９】

要するに、ステップ４２，４３では、変化後のフォーカス位置にて演算により得られる画角のうち、画角決定処理により演算された基準画角ωｏｒｇを間に含む２つの画角ωｏｒｇ’とωｏｒｇ’’を求め、これら２つの画角を得るための２つのズーム部の位置Ｐｚｉ，Ｐｚｉ’から直線近似によりズーム位置指令Ｚｃを求めている。
【００４０】
こうしてズーム指令位置Ｚｃを決定すると、ステップ４４に進んで、ズーム位置がズーム指令位置Ｚｃになるようにズームモータ５に駆動信号であるズーム指令信号を出力し、ステップ４５に進んで処理を終了する。
【００４１】
なお、ズームレンズ６の広角側の端点から望遠側の端点までの範囲をｎ×２Ｎ（Ｎは任意の定数）で表せるようにすると、Ｐｚｉ’−Ｐｚｉ＝２Ｎとなる。本実施形態のように演算装置３にて除算や乗算を行う場合、対象となる数が２のべき乗であると、シフト演算にて対処できるので、計算時間の大幅な短縮を実現することができる。同様の理由から、フォーカスレンズ１０の無限側の端点から至近側の端点までの範囲をｍ×２Ｍ（Ｍは任意の定数）で表せるようにしておく。
【００４２】
以上のように構成した画角補正機能は、画角算出時における誤差を少なくし、また近似平面を用いることによる画角の変動をなくし、さらに記憶領域の占有を少なくすることを実現したものである。
【００４３】
なお、本実施形態では、フォーカスレンズ１０を動かす際に、動いた後（位置の変化後）のフォーカス位置として、実際に動いた後のフォーカス位置（位置検出器１１により検出された位置）を用いて画角補正処理を行う場合について説明したが、フォーカスデマンド等から入力されるフォーカス操作信号から得られるフォーカス位置指令やフォーカスレンズ１０の移動速度を加味した所定時間後の位置（つまり、フォーカスレンズ１０が実際に動く前に得られる、動いた後のフォーカス位置）を用いて画角補正処理を行うようにしてもよい。
【００４４】
さらに、本実施形態では、直線近似により画角（基準画角）を演算する場合について説明したが、曲線近似を用いて画角を演算するようにしてもよい。
【００４５】
（第２実施形態）
図６および図７には、本発明の第２実施形態であるレンズ装置に備えられた画角プリセット機能の動作フローを示している。なお、本実施形態のレンズ装置の構成は、第１実施形態の図１にて説明したレンズ装置の構成と同様であるので、共通する構成要素については第１実施形態と同符号を付して説明に代える。
【００４６】
演算装置３では、予め決められているサンプリング時間毎に、図６に示す現在の画角の記憶動作フローと、図７に示す記憶した画角を得るためのズームレンズ６の駆動フローとを実行する。
【００４７】
まず、図６に示す画角の記憶動作フローについて説明する。演算装置３は、サンプリング時毎にステップ５０から処理をスタートする。処理がスタートすると、まず、現在の画角をデータ記憶部材１２にメモリするか否かを判別するための画角メモリフラグがセットされているかどうかを確認する（ステップ５１）。この画角メモリフラグは、不図示のプリセットスイッチ等が操作されることによりセットされる。画角メモリフラグがセットされていなければステップ５５に進んで処理を終了する。
【００４８】
一方、画角メモリフラグがセットされていれば、現在のズームレンズ６の位置とフォーカスレンズ１０の位置を位置検出器７，１１を通じて検出し（ステップ５２）、検出したズーム位置およびフォーカス位置により現在の画角ωｏｒｇを算出決定する。（ステップ５３）。このときの画角決定処理は、第１実施形態の図４に示すフローに従って行う。
【００４９】
次に、ステップ５４に進み、算出した画角ωｏｒｇを移動画角（プリセット画角）としてデータ記憶部材１２にメモリし、ステップ５５にて処理を終了する。なお、移動画角を複数、データ記憶部材１２にメモリできるようにしてもよい。
【００５０】
次に、図７に示す駆動フローについて説明する。演算装置３はサンプリング時毎にステップ６０から処理をスタートする。処理がスタートすると、メモリしたプリセット画角ωｏｒｇにズームレンズ６を移動させるか否かを判別するためのズームレンズ移動フラグがセットされているかどうかを確認する（ステップ６１）。ズームレンズ移動フラグは、不図示のリコールスイッチ等が操作されることによりセットされる。ズームレンズ移動フラグがセットされていなければステップ６５に進んで処理を終了する。
【００５１】
一方、ズームレンズ移動フラグがセットされていれば、現在のフォーカスレンズ１０の位置を位置検出器１１を通じて検出し（ステップ６２）、検出したフォーカス位置とメモリしてある移動画角ωｏｒｇから、画角が移動画角ωｏｒｇとなるように、ズーム指令位置Ｚｃを算出し、ズーム指令信号を出力する（ステップ６３）。このときのズーム指令位置Ｚｃの算出は、第１実施形態の図５に示したフローに従って行う。
【００５２】
次にステップ６４に進み、ズーム指令位置Ｚｃまでのズームレンズ６の移動が完了したか否かを確認し、完了したならばステップ６５に進み処理を終了する。
【００５３】
なお、上述したように移動画角が複数メモリされている場合には、不図示のスイッチ等の選択操作部材によって、どの移動画角が得られるようにズームレンズ６を駆動するかを選択することができるようにする。
【００５４】
このように本実施形態によれば、撮影者が任意の移動画角をメモリしておき、その移動画角を得たいときに上記リコールスイッチ等を操作することによって、その移動画角を得るための、その時点でのフォーカス位置を加味したズーム位置にズームレンズ６が駆動される。このため、移動画角をメモリした時点からフォーカス位置が変化していても、メモリした画角を瞬時にかつ正確に再現することができる。したがって、撮影者の違和感をなくすることができる。
【００５５】
（第３実施形態）
上記各実施形態では、位置検出器７，１１により検出されたフォーカス位置およびズーム位置を用いて画角決定処理を行う場合について説明したが、フォーカス位置やズーム位置のプリセット値や指令値といった実際のレンズ駆動前の位置情報を用いて画角決定処理を行うようにしてもよい。
【００５６】
これにより、例えば、図８（ａ）に示すように、フォーカス位置およびズーム位置の双方を上記駆動前の位置情報としてセットし（ステップ７１）、これら位置情報が示す位置にフォーカスレンズ１０およびズームレンズ６を駆動するとした場合に、どのような画角が得られるかを前もって予測演算し（ステップ７２）、表示する（ステップ７３）ことが可能になる。
【００５７】
また、ズーム位置をボリューム等によってプリセットできる構成を採用する場合に、図８（ｂ）に示すように、プリセット値と位置検出器１１によって検出されたフォーカス位置とから画角を求めておき（ステップ８１，８２）、その後ズーム位置のリコール操作がなされた際に（ステップ８３）、そのときのフォーカス位置を検出し（ステップ８４）、このフォーカス位置に対して求めた画角が得られるようにズームプリセット位置を補正して（ステップ８５）、ズームレンズ６を駆動することにより（ステップ８６）、画角を維持することも可能となる。
【００５８】
【発明の効果】
以上説明したように、本発明によれば、相互に隣接する４点の画角データを用いて画角を演算するため、３点のデータを用いて画角を演算する場合に比べて誤差を小さくすることができる。しかも、１つのフォーカス・ズーム位置に対して１つの画角データを記憶させておけばよいので、従来のように１つのフォーカス・ズーム位置に対して複数の係数データを記憶させなければならない場合に比べて、使用する記憶領域を小さくすることができる。
【００５９】
なお、フォーカス部の位置が変化する際に、上記演算手法を用いて演算された画角と変化後のフォーカス部の位置とに基づいて、フォーカス部の位置変化に伴う画角変動を補正するためのズーム部の目標移動位置を演算し、ズーム部を移動させるようにすれば、正確性の高い画角補正機能を実現することができる。
【００６０】
また、上記演算手法を用いて演算された画角を記憶し、フォーカス部の検出位置にて記憶画角を与えるズーム部の目標移動位置を演算し、ズーム部を移動させるようにすれば、再現性の高い画角プリセット機能を実現することができる。
【００６１】
そして、以上の発明に係るレンズ装置をカメラに装着してカメラシステムを構成することにより、撮影者が意図した画角を正確に維持したり容易に得たり等しながら撮影を行うことができるカメラシステムを実現することが可能となる。
【図面の簡単な説明】
【図１】本発明の第１実施形態であるレンズ装置のブロック図。
【図２】上記レンズ装置における画角補正機能の動作フローチャート。
【図３】上記レンズ装置の記憶領域に記憶保持させる画角データのマップの概念図。
【図４】上記画角補正機能における画角決定処理のフローチャート。
【図５】上記画角補正機能における画角補正処理のフローチャート。
【図６】本発明の第２実施形態であるレンズ装置における画角プリセット機能の動作フローチャート。
【図７】上記画角プリセット機能におけるズーム駆動処理のフローチャート。
【図８】本発明の第３実施形態であるレンズ装置における画角演算を利用した動作のフローチャート。
【符号の説明】
１・・・・ズーム操作部材
２・・・・フォーカス操作部材
３・・・・演算装置
４、８・・増幅器
５・・・・ズームモータ
６・・・・ズームレンズ
７、１１・位置検出器
９・・・・フォーカスモータ
１０・・・フォーカスレンズ
１２・・・データ記憶部材
１３・・・Ｄ／Ａ変換器
１４・・・ズーム信号切替スイッチ
１５・・・カメラ
１６・・・レンズ装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens apparatus having a movable zoom unit and a focus unit.
[0002]
[Prior art]
In the lens device, the field of view can be increased or decreased by moving the lens position by controlling the zoom unit, but when the focus unit is controlled, the field angle is also changed by moving the lens position in the same way. It will change. That is, even if a desired angle of view is set by the zoom unit, the set angle of view varies due to control of the focus unit. For this reason, there has been proposed a lens apparatus having a so-called angle-of-view correction function for controlling the zoom unit so that the angle of view does not vary when the focus unit is controlled.
[0003]
In such a lens apparatus, when executing the angle of view correction function, first, the lens movement range of the zoom unit and the lens movement range of the focus unit are each divided into a plurality of parts, and the lens position of the zoom unit at each division point ( An angle of view (ωij) is calculated by optical calculation from a lens position (Pfj: hereinafter referred to as a focus position) of the focus portion and Pzi (hereinafter referred to as a zoom position).
[0004]
From these three parameters, two approximate plane equations that pass through three of the four adjacent dividing points are derived.
[0005]
ωorg = Czij × Zp + Cfij × Fp + ωij
Zc = (1 / Czij) × (ωorg−Cfij × Fp−ωij)
Where Czij: coefficient for the zoom position of the approximate plane Cfij: coefficient for the focus position of the approximate plane ωij: angle of view coefficient at the dividing point ωorg: reference angle of view to be maintained Zp: zoom position Fp: focus position Zc: zoom command position The four coefficients ωij, Czij, Cfij, 1 / Czij obtained here are obtained at each division point, mapped and stored in the storage area, and calculation of the reference field angle (ωorg) and zoom command position (Zc) Is calculated, and the angle of view fluctuation correction operation is performed.
[0006]
Some conventional lens devices have a so-called zoom preset function. In this method, the zoom position is moved to a set position set in advance by an operation means such as a volume. Thus, the zoom position can be instantaneously moved to the position selected and set by the photographer, and the versatility of shooting can be expanded.
[0007]
[Problems to be solved by the invention]
However, in the conventional angle-of-view correction function, since the reference angle of view is calculated using an approximate plane that passes through three of the four adjacent dividing points, the closer to the remaining one dividing point, There is a problem that an error in the calculated value of the reference angle of view becomes large. In addition, since the approximate plane to be used changes with the movement of the focus position, the angle of view changes due to the error at the time of the change. Further, since four pieces of data to be stored and held are necessary for one division point, there is a problem that a limited storage area must be occupied.
[0008]
In addition, since the conventional zoom preset function only moves the zoom section to a preset position, if the focus position has changed since the zoom position was set, the zoom section can be moved to the set position. There is a problem that the original angle of view cannot be obtained and the photographer feels uncomfortable.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, in the present invention, a storage unit storing a plurality of view angle data obtained based on a plurality of position data of a focus unit and a plurality of position data of a zoom unit, a position detection unit, and the like The four adjacent view angle data obtained based on the given positions of the focus unit and zoom unit are read from the storage means, and the given focus unit and zoom unit are read from the four view angle data. The lens apparatus is configured by providing calculation means for approximately calculating the angle of view with respect to the position.
[0010]
Here, for example, the calculation means interpolates the angle-of-view data for every two points with respect to the same zoom portion position among the above-described four-point angle-of-view data, and the straight line of the angle of view with respect to the given focus portion position. Two approximate data are obtained, and linear approximation data of the angle of view with respect to the position of the given zoom unit that interpolates these two linear approximation data is obtained, and the angle of view with respect to the detected position of the given focus unit and zoom unit is To do.
[0011]
The angle-of-view data, position data, and straight line approximation data mentioned here include data indicating the angle of view and position as they are, and data corresponding to the angle of view and position (simplified data).
[0012]
As described above, in the present invention, since the angle of view is calculated using the four angle-of-view data adjacent to each other, the error can be reduced as compared with the case of calculating the angle of view using the three-point data. It becomes. In addition, since it is only necessary to store one field angle data for one focus / zoom position, a plurality of coefficient data must be stored for one focus / zoom position (division point) as in the prior art. It is possible to suppress the occupation of the storage area compared to the case where it is necessary.
[0013]
And by using the said invention, it becomes possible to implement | achieve a highly accurate view angle correction function. Specifically, when the position of the focus unit changes, the angle-of-view variation due to the change in the focus unit position is corrected based on the angle of view calculated by the calculation unit and the position of the focus unit after the change. An angle-of-view variation correcting means for calculating a target movement position of the zoom unit for moving the zoom unit to the target movement position is provided.
[0014]
Further, it is possible to realize an angle-of-view preset function that can accurately reproduce a preset image quality regardless of the focus position using the above invention. In particular,
Includes a preset switch and recall switch, along with the operation of the preset switch stores the angle which the storage means is calculated by calculating means, in association with the operation of the recall switch, the position of the focus portion On the other hand, there is provided zoom drive means for calculating a target movement position of the zoom unit for obtaining the angle of view stored in the storage means and moving the zoom unit to the target movement position.
[0015]
Then, by mounting the lens device according to the above invention on a camera to constitute a camera system, a camera system capable of shooting while accurately maintaining and reproducing the angle of view intended by the photographer It can be realized.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 shows the configuration of a lens apparatus according to the first embodiment of the present invention. In the figure, 16 is a lens device, and 15 is a camera to which this lens device is connected so as to be communicable.
[0017]
Reference numeral 3 denotes an arithmetic device such as a microcomputer, and one of its outputs is input to the A terminal of the zoom signal changeover switch 14 via the D / A converter 13. When the zoom signal changeover switch 14 is set to the A terminal side, the output of the arithmetic unit 3 is input to the zoom motor 5 through the amplifier 4 and the zoom motor 5 is driven. When the zoom motor 5 is driven, a zoom lens (zoom unit) 6 having a zooming function is driven in the optical axis direction.
[0018]
The output of the position detector 7 that detects the position of the lens 6 (hereinafter referred to as the zoom position) is fed back to the arithmetic unit 3.
[0019]
Further, a zoom operation signal from the zoom operation member 1 such as a seesaw pot or a zoom demand is input to the B terminal of the zoom signal changeover switch 14 (B). The arithmetic device 3 outputs a signal for switching the set of the zoom signal selector switch 14 to the A terminal side and the B terminal side, and normally the zoom signal selector switch 14 is set to the B terminal side. .
[0020]
Reference numeral 2 denotes a focus operation member such as a focus demand. A focus operation signal output from the focus operation member 2 is input to the focus motor 9 via the amplifier 8 to drive the focus motor 9. When the focus motor 9 is driven, a focus lens (focus section) 10 having a focusing function is driven in the optical axis direction.
[0021]
The output of the position detector 11 that detects the position of the focus lens 10 (hereinafter referred to as the focus position) is fed back to the arithmetic unit 3 and the amplifier 8.
[0022]
Reference numeral 12 denotes a data storage member (for example, EEPROM), in which field angle data necessary for performing a field angle correction calculation described later is stored in advance. In the arithmetic unit 3, in a series of calculations for correcting the change in the angle of view due to focusing, the calculation is performed using the data in this region. Specific contents stored in this area will be described later.
[0023]
In the lens apparatus configured as described above, when the operator operates the zoom operation member 1 to adjust the focal length, the zoom operation signal changes according to the operation amount, and the zoom lens 6 is driven. Similarly, when the focus operation member 2 is operated in order to adjust the object distance, the focus operation signal changes according to the operation amount, and the focus lens 10 is driven.
[0024]
The arithmetic device 3 executes a process according to the flow shown in FIG. 2 at every predetermined sampling time. Next, this flow will be described.
[0025]
The processing of the arithmetic device 3 starts from step 20 every sampling time. When the process starts, it is confirmed whether or not an angle-of-view correction flag for determining whether or not angle-of-view variation correction is permitted (step 21). This view angle correction flag is set by operating a view angle correction mode selection switch (not shown) or the like. If the angle of view correction flag is not set, the process proceeds to step 27 and the process is terminated.
[0026]
On the other hand, if the angle of view correction flag is set, the current zoom position and focus position are detected through the position detectors 7 and 11 (step 22). Next, it is confirmed whether or not the focus position is moving (step 23), and if not, the current field angle (reference field angle ωorg) is determined based on the detected focus position (Fp) and zoom position (Zp) ( Step 25). This angle of view determination process will be described later. After the angle of view is determined, the process ends at step 27.
[0027]
If the focus position has moved in step 23, a zoom command position (target movement position: Zc) is determined to make the change in the angle of view caused by the change in the focus position constant (to correct the angle-of-view variation). Then, after setting the zoom signal selector switch 14 to the A terminal side, a zoom command signal is output (step 24), and the zoom lens 6 is driven (step 26). This angle of view correction process will be described later. After the angle of view correction process, the process ends at step 27.
[0028]
Next, the storage area of the data storage member 12 will be described. First, the drive range from the wide-angle end point to the telephoto end point of the zoom lens 6 is divided equally by an arbitrary number n, and the drive range from the infinite end point to the closest end point of the focus lens 10 is arbitrarily set. Equally divided by several m. Further, an angle of view (ωij) at the i-th division point (Pzi) of zoom and the j-th division point (Pfj) of focus is obtained in advance by optical calculation.
[0029]
These calculations are performed at all the dividing points on the map shown in FIG. 3, and the angle of view (ωij) is mapped and stored in the storage area. The field angle data thus mapped is used in the process of calculating the reference field angle in the field angle determination process and the zoom command position in the field angle correction process.
[0030]
Note that the angle-of-view data referred to here may be data indicating the angle of view as it is, or data corresponding to the angle of view, such as a simplified view of the angle of view.
[0031]
Next, the angle-of-view determination process performed in step 25 of FIG. 2 will be described using the flow of FIG. When the zoom position is detected by the position detector 7, first, Pzi is set so that the zoom position (Zp) is between the i-th division point (Pzi) and the i + 1-th division point (Pzi ′) of the zoom. decide. When the position detector 11 detects the focus position, the focus position (Fp) is similarly between the jth division point (Pfj) and the j + 1th division point (Pfj ′) of the focus. Pfj is determined as follows. Then, the field angle data ωij on the map for the division point (Pzi, Pfj) is determined, and the process proceeds to Step 32.
[0032]
In step 32, first, the angle of view (ωorg ′) when the zoom position and the focus position are Pzi and Fp is calculated by linear approximation using the following equation.
[0033]

Similarly, the angle of view (ωorg ″) when the zoom position and the focus position are Pzi ′ and Fp is calculated by linear approximation using the following equation.
[0034]

Next, using the obtained two angle of view, the angle of view when the zoom position and the focus position are Zp and Fp, that is, the reference angle of view (ωorg) is calculated by linear approximation using the following equation.
[0035]

In short, in step 32, every two points with respect to the same zoom position Pzi in the view angle data (ωij, ωij ′, ωi′j, ωi′j ′) of the four divided points adjacent to each other with the view angle data ωij as a representative. Angle-of-view data (ωij and ωij ′, ωi′j and ωi′j ′) are calculated by linear approximation to two angle-of-view linear approximation data (ωorg ′ and ωorg ″) with respect to the focus position Fp. Then, the angle-of-view linear approximation data ωorg for the zoom position Zp for interpolating these two angle-of-view straight line approximation data (ωorg ′, ωorg ″) is calculated and determined as the reference angle of view. When the reference angle of view is thus determined, the process proceeds to step 33 and the process is terminated.
[0036]
Next, the angle of view correction processing performed in step 24 of FIG. 2 will be described using the flow of FIG. First, when the position after the focus lens 10 is moved is detected through the position detector 11, the focus position (Fp) is determined between the jth division point (Pfj) of the focus and the j + 1th division point (Pfj ′). Pfj is determined so as to be between (step 41).
[0037]
Next, on the basis of this Pfj, using the above-described equation, i is changed from 0 to n to calculate the angle of view ωorg ′ and ωorg ″ as data, and the reference angle of view ωorg is the angle of view ωorg ′, i that falls between ωorg ″ is found, and ωij that is representative of the four view angle data is determined (step 42).
[0038]
Next, the zoom command position Zc when the angle of view and the focus position are ωorg and Fp is calculated by linear approximation using the following equation (step 43).
[0039]

In short, in Steps 42 and 43, two angles of view ωorg ′ and ωorg ″ including the reference angle of view ωorg calculated by the angle-of-view determination process among the angles of view obtained by calculation at the changed focus position. The zoom position command Zc is obtained by linear approximation from the positions Pzi and Pzi ′ of the two zoom units for obtaining these two angles of view.
[0040]
When the zoom command position Zc is determined in this way, the process proceeds to step 44 where a zoom command signal, which is a drive signal, is output to the zoom motor 5 so that the zoom position becomes the zoom command position Zc, and the process proceeds to step 45 and the process is terminated. .
[0041]
If the range from the wide-angle end point to the telephoto end point of the zoom lens 6 can be expressed by n × 2N (N is an arbitrary constant), Pzi′−Pzi = 2N. When division or multiplication is performed by the arithmetic unit 3 as in the present embodiment, if the target number is a power of 2, it can be handled by shift calculation, so that the calculation time can be significantly reduced. . For the same reason, the range from the end point on the infinite side of the focus lens 10 to the end point on the closest side is expressed by m × 2M (M is an arbitrary constant).
[0042]
The angle-of-view correction function configured as described above reduces the error in calculating the angle of view, eliminates fluctuations in the angle of view due to the use of an approximate plane, and further reduces the occupation of the storage area. is there.
[0043]
In the present embodiment, when the focus lens 10 is moved, the focus position after actual movement (position detected by the position detector 11) is used as the focus position after movement (after change in position). In the above description, the angle of view correction process is performed. However, a position after a predetermined time in consideration of a focus position command obtained from a focus operation signal input from a focus demand or the like and a moving speed of the focus lens 10 (that is, the focus lens 10 The angle-of-view correction processing may be performed using the focus position after movement obtained before actually moving.
[0044]
Furthermore, in the present embodiment, the case where the angle of view (reference angle of view) is calculated by linear approximation has been described, but the angle of view may be calculated using curve approximation.
[0045]
(Second Embodiment)
6 and 7 show an operation flow of the angle-of-view preset function provided in the lens apparatus according to the second embodiment of the present invention. Since the configuration of the lens device of the present embodiment is the same as the configuration of the lens device described in FIG. 1 of the first embodiment, common constituent elements are denoted by the same reference numerals as those of the first embodiment. Instead of explanation.
[0046]
The arithmetic unit 3 executes the current view angle storage operation flow shown in FIG. 6 and the zoom lens 6 drive flow for obtaining the stored view angle shown in FIG. 7 at predetermined sampling times. To do.
[0047]
First, the operation flow for storing the angle of view shown in FIG. 6 will be described. The arithmetic unit 3 starts processing from step 50 every sampling time. When the process starts, first, it is confirmed whether or not an angle of view memory flag for determining whether or not to store the current angle of view in the data storage member 12 is set (step 51). This angle of view memory flag is set by operating a preset switch (not shown) or the like. If the angle of view memory flag is not set, the process proceeds to step 55 and the process is terminated.
[0048]
On the other hand, if the view angle memory flag is set, the current position of the zoom lens 6 and the position of the focus lens 10 are detected through the position detectors 7 and 11 (step 52), and the current zoom position and focus position are detected based on the detected zoom position and focus position. The angle of view ωorg is calculated and determined. (Step 53). The angle-of-view determination process at this time is performed according to the flow shown in FIG. 4 of the first embodiment.
[0049]
Next, the process proceeds to step 54, where the calculated field angle ωorg is stored in the data storage member 12 as a moving field angle (preset field angle), and the process ends in step 55. Note that a plurality of movement angles of view may be stored in the data storage member 12.
[0050]
Next, the driving flow shown in FIG. 7 will be described. The arithmetic unit 3 starts processing from step 60 every sampling time. When the process starts, it is checked whether or not a zoom lens movement flag for determining whether or not to move the zoom lens 6 to the stored preset angle of view ωorg is set (step 61). The zoom lens movement flag is set by operating a recall switch (not shown) or the like. If the zoom lens movement flag is not set, the process proceeds to step 65 to end the process.
[0051]
On the other hand, if the zoom lens movement flag is set, the current position of the focus lens 10 is detected through the position detector 11 (step 62), and the angle of view is determined from the detected focus position and the stored movement angle of view ωorg. The zoom command position Zc is calculated so that becomes the movement angle of view ωorg, and a zoom command signal is output (step 63). The calculation of the zoom command position Zc at this time is performed according to the flow shown in FIG. 5 of the first embodiment.
[0052]
Next, the process proceeds to step 64, where it is confirmed whether or not the movement of the zoom lens 6 to the zoom command position Zc has been completed. If it has been completed, the process proceeds to step 65 and the process is terminated.
[0053]
When a plurality of moving field angles are stored as described above, a selection operation member such as a switch (not shown) selects which moving field angle is to be driven so as to obtain a moving field angle. To be able to.
[0054]
As described above, according to the present embodiment, the photographer stores an arbitrary moving angle of view, and obtains the moving angle of view by operating the recall switch or the like when the moving angle of view is desired. The zoom lens 6 is driven to a zoom position that takes into account the focus position at that time. For this reason, even if the focus position has changed since the movement angle of view was stored, the stored angle of view can be instantaneously and accurately reproduced. Therefore, it is possible to eliminate a sense of incongruity of the photographer.
[0055]
(Third embodiment)
In each of the above-described embodiments, the case where the angle-of-view determination processing is performed using the focus position and the zoom position detected by the position detectors 7 and 11 has been described. However, actual values such as a preset value and a command value of the focus position and the zoom position are described. The angle-of-view determination process may be performed using position information before driving the lens.
[0056]
Accordingly, for example, as shown in FIG. 8A, both the focus position and the zoom position are set as the position information before driving (step 71), and the focus lens 10 and the zoom lens are set at the positions indicated by the position information. 6 is driven, it is possible to predict and calculate in advance what angle of view will be obtained (step 72) and display it (step 73).
[0057]
Further, when adopting a configuration in which the zoom position can be preset by a volume or the like, as shown in FIG. 8B, the angle of view is obtained from the preset value and the focus position detected by the position detector 11 (step 81, 82), when a recall operation for the zoom position is subsequently performed (step 83), the focus position at that time is detected (step 84), and the zoom is performed so that the angle of view obtained with respect to this focus position is obtained. The angle of view can be maintained by correcting the preset position (step 85) and driving the zoom lens 6 (step 86).
[0058]
【The invention's effect】
As described above, according to the present invention, since the angle of view is calculated using the four angle-of-view data adjacent to each other, an error is calculated as compared with the case where the angle of view is calculated using the three-point data. Can be small. In addition, since it is only necessary to store one angle of view data for one focus / zoom position, a plurality of coefficient data must be stored for one focus / zoom position as in the prior art. In comparison, the storage area to be used can be reduced.
[0059]
When the position of the focus section changes, in order to correct the angle-of-view fluctuation accompanying the position change of the focus section based on the field angle calculated using the above calculation method and the position of the focus section after the change. If the target movement position of the zoom unit is calculated and the zoom unit is moved, a highly accurate field angle correction function can be realized.
[0060]
In addition, if the angle of view calculated using the above calculation method is stored, the target moving position of the zoom unit that gives the stored angle of view is calculated at the detection position of the focus unit, and the zoom unit is moved, it is reproduced. It is possible to realize a highly reliable angle of view preset function.
[0061]
A camera capable of shooting while accurately maintaining or easily obtaining the angle of view intended by the photographer by configuring the camera system by mounting the lens device according to the above invention on the camera. A system can be realized.
[Brief description of the drawings]
FIG. 1 is a block diagram of a lens apparatus according to a first embodiment of the present invention.
FIG. 2 is an operation flowchart of a field angle correction function in the lens apparatus.
FIG. 3 is a conceptual diagram of a map of field angle data to be stored and held in a storage area of the lens device.
FIG. 4 is a flowchart of a field angle determination process in the field angle correction function.
FIG. 5 is a flowchart of a view angle correction process in the view angle correction function.
FIG. 6 is an operation flowchart of an angle of view preset function in the lens apparatus according to the second embodiment of the present invention.
FIG. 7 is a flowchart of zoom drive processing in the view angle preset function.
FIG. 8 is a flowchart of an operation using field angle calculation in the lens apparatus according to the third embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Zoom operation member 2 ... Focus operation member 3 ... Arithmetic unit 4, 8 ... Amplifier 5 ... Zoom motor 6 ... Zoom lens 7, 11 ... Position detector 9. Focus motor 10 ... Focus lens 12 ... Data storage member 13 ... D / A converter 14 ... Zoom signal changeover switch 15 ... Camera 16 ... Lens device

Claims (10)

Storage means for storing a plurality of angle-of-view data obtained based on a plurality of position data of the focus section and a plurality of position data of the zoom section;
Four view angle data adjacent to each other obtained based on the positions of the given focus portion and zoom portion are read from the storage means, and the given focus portion and zoom are obtained from the four view angle data. And a calculating means for calculating an angle of view with respect to the position of the portion approximately. Focus position detection means for detecting the position of the focus section; and zoom position detection means for detecting the position of the zoom section;
The lens apparatus according to claim 1, wherein the given positions of the focus unit and the zoom unit are detection positions by the focus position detection unit and the zoom position detection unit. The lens apparatus according to claim 1, wherein at least one of the given positions of the focus unit and the zoom unit is a position commanded or set before driving the focus unit and the zoom unit. The calculation means obtains linear approximation data of an angle of view from the four view angle data and the given position of the focus portion, and gives the linear approximation data of the angle of view from the linear approximation data and the given position of the zoom portion. 4. The lens apparatus according to claim 1, wherein an angle of view with respect to the positions of the focus unit and the zoom unit is obtained. The calculation means interpolates two angle-of-view data for the same zoom portion of the four-point angle-of-view data, and obtains two linear approximation data of the angle of view for the given focus portion position. And obtaining linear approximation data of an angle of view with respect to the position of the given zoom unit that interpolates these two linear approximation data, and obtaining the angle of view with respect to the position of the given focus unit and zoom unit. The lens device according to claim 4. When the position of the focus section changes, based on the changed position of the focus section and the angle of view calculated by the calculation means, the angle of view variation due to the change in position of the focus section is corrected. 6. The lens apparatus according to claim 1, further comprising an angle-of-view variation correction unit that calculates a target movement position of the zoom unit and moves the zoom unit to the target movement position. The field angle fluctuation correcting unit obtains two field angles including the field angle calculated by the calculation unit among the field angles obtained by calculation with respect to the position of the focus unit after the change. The lens apparatus according to claim 6, wherein the target movement position is calculated by linear approximation from position data of two zoom units capable of obtaining an angle of view. Includes a preset switch and recall switch, along with the operation of the preset switch, the storage means stores the angle computed by the computing means, in accordance with the operation of the recall switch, the focus unit the target moving position of the zoom portion for obtaining a field angle stored in the storage means and calculating relative positions, characterized in that it has a zoom driving hands stage for moving the zoom portion to the target position after movement according Item 6. The lens device according to any one of Items 1 to 5. The zoom driving means obtains two angles of view including the angle of view calculated by the calculating means among the angles of view obtained by calculation with respect to the position of the focus unit, and obtains these two angles of view. The lens apparatus according to claim 8, wherein the target movement position is calculated by linear approximation from position data of the two zoom units. A camera system comprising: the lens device according to claim 1; and a camera to which the lens device is attached.

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