Video camera apparatus

• US 20050083430A1
• Filed: 10/19/2004
• Published: 04/21/2005
• Est. Priority Date: 05/27/1993
• Status: Active Grant

• Current Assignee: Hiroto Ohkawara, Masahide Hirasawa, Tatsuya Yamazaki
• Original Assignee: Hiroto Ohkawara, Masahide Hirasawa, Tatsuya Yamazaki
• Inventors: Yamazaki, Tatsuya, Ohkawara, Hiroto, Hirasawa, Masahide
• Granted Patent: US 7,456,898 B2
• Time in Patent Office: Days
• US Class Current: 348/349
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming

Abstract

A video camera includes a gate circuit for extracting a sharpness signal relative to an area which is set in a portion of a picture, a focus adjusting device for performing focus adjustment on the basis of the sharpness signal relative to the area, and an area selecting circuit for controlling the gate circuit to vary the area in size and determining a size of the area during a driving of a variator lens in accordance with a size of the area and a focal length used before the driving of the variator lens.

Claims

1. An automatic focus adjusting device comprising:

area setting unit which sets in a picture a plurality of areas including a first area having a higher priority and a second area which has a lower priority than the first distance measuring area;

driving unit which drives an optical element for focus adjustment on the basis of a signal putted out from the area by area setting unit; and

control unit which makes a decision as to whether a subject the distance to which can be measured is present in the first area.

2. An automatic focus adjusting device according to claim 1, wherein said control unit is arranged to perform the focus adjusting operation on the basis of information relative to the first distance measuring area if the subject the distance to which can be measured is present in the first distance measuring area.

3. An automatic focus adjusting method comprising:

an area setting step for setting in a picture a plurality of areas including a first area having a higher priority and a second area which has a lower priority than the first distance measuring area;

a driving step for driving an optical element for focus adjustment on the basis of a signal put out from the area in the area setting step; and

a control step for making a decision as to whether a subject the distance to which can be measured is present in the first area.