IMAGING DEVICE AND CONTROL METHOD OF THE SAME

PROBLEM TO BE SOLVED: To reduce focusing deviations accompanied by an insertion state into an optical path of a half mirror in consideration for an influence of errors due to K value in an imaging device equipped with the half mirror.SOLUTION: An imaging device has: a main mirror that is configured using a half mirror; imaging means that receives a light flux passing through an imaging optical system to photoelectrically convert the received light influx; focus detection means that acquires an amount of image deviation based on a signal output from the imaging means, and detects an amount of defocus from the amount of image deviation, using a conversion coefficient; and control means that controls focus adjustments on the basis of the amount of defocus. The control means is configured to switch, in accordance with the conversion coefficient, a first mode in which focus adjustments are made based on the signal output from the imaging means in a state with the main mirror put downward, and a second mode in which the focus adjustments are made based on the signal output from the imaging means in a state with the mina mirror put upward.SELECTED DRAWING: Figure 4 【課題】 ハーフミラーを備えた撮像装置において、Ｋ値による誤差の影響を考慮して、ハーフミラーの光路中への挿入状態の変化に伴うピントずれを低減する。【解決手段】 撮像装置は、ハーフミラーを用いて構成された主ミラーと、撮影光学系を通過した光束を受光して光電変換する撮像手段と、撮像手段から出力された信号に基づく像ずれ量を取得し、換算係数を用いて像ずれ量からデフォーカス量を検出する焦点検出手段と、デフォーカス量に基づいて焦点調節を制御する制御手段とを有する。制御手段は、換算係数に応じて、主ミラーをダウンさせた状態で撮像手段から出力された信号に基づいて焦点調節を制御する第１のモードと、主ミラーをアップさせた状態で撮像手段から出力された信号に基づいて焦点調節を制御する第２のモードを切り替える。【選択図】 図４