Focus detection device

1. A focus detection device comprising:

a plurality of line sensors;

a plurality of monitor sensors provided adjacent to said line sensors, wherein each of said monitor sensors monitors the quantity of light received by a corresponding one of said line sensors, from an autofocus optical system that projects light onto the line sensors; and

a control device which selectively controls the driving of a combination of line sensors and monitor sensors, selected from said line sensors and said monitor sensors provided in said focus detection device, in accordance with a type of the autofocus optical system that projects light onto the line sensors,

wherein said line sensors, said monitor sensors, and said control device are provided on a common circuit board.

2. The focus detection device according to claim 1 , wherein said control device selects a combination of said line sensors and said monitor sensors to be used, based on an externally input signal.

3. The focus detection device according to claim 1 , further comprising logic storing a plurality of selection modes for said combination of said line sensors and said monitor sensors to be used, wherein a signal specifying said selection mode is externally input to the control device so that said control device controls the driving of said combination of said line sensors and said monitor sensors corresponding to said selection mode.

4. The focus detection device according to claims 1 ,

wherein each of said line sensors comprises sensor areas designating a standard sensor area and a reference sensor area, each of said standard sensor area and said reference sensor area being further designated with a plurality of sub-areas;

wherein at least one of said monitor sensors is provided for each standard area; and

wherein said control device controls the driving of said monitor sensors in each of said sub-areas.

5. The focus detection device according to claims 1 ,

wherein said control device controls integration termination of said line sensors, including the corresponding standard area, based on an output of the selected monitor sensor.

6. The focus detection device according to claim 1 ,

wherein said focus detection device is provided in a focus detecting module of a camera.

7. The focus detection device according to claim 6 ,

wherein said control device selects at least one of said monitor sensors and at least one corresponding said line sensors to be used, based on a command transmitted from a second control device which is provided in a camera body of said camera, in order to control the driving of the selected said monitor sensor and said line sensor.

8. The focus detection device according to claim 1 , further comprising a memory which stores a plurality of different selection modes, each of said selection modes corresponding to a combination of said line sensors and said monitor sensors to be used;

wherein said control device selects one selection mode corresponding to a signal specifying said one selection mode, transmitted from a control device of a camera body, from said selection modes stored in said memory so as to control the driving of the corresponding line sensor and monitor sensor based on said one selected mode.

9. The focus detection device according to claim 4 ,

wherein said standard sensor area, which uses a portion of said sensor areas, is integrated by an adjacent monitor sensor which integrates the entire said standard sensor area.