Image capturing apparatus, image capturing method, image capturing circuit, and program

1. An image capturing apparatus for capturing an image of a target object by optically scanning the target object by moving in a predetermined scanning direction, the apparatus comprising:

light-receiving devices that are arranged on a light-receiving surface of the image capturing apparatus in a direction perpendicular to the scanning direction, where each light-receiving device has a plurality of light-receiving elements in the direction perpendicular to the scanning direction and accumulates an electric charge according to an amount of light received from the target object; and

an output device that outputs the electric charge accumulated by each light-receiving device regularly at a predetermined output period which is determined in a manner such that the larger the length in the scanning direction of a light-receiving range for the target object, which is covered by the light-receiving device, the longer the output period, wherein:

the length in the scanning direction of the light-receiving range for the target object is represented by:

D=h {tan(θ+α)−tan α}  [Formula 6]

where h denotes a distance obtained by orthogonal projection of each light-receiving device onto the target object, θ denotes an angle of view of the light-receiving device in the scanning direction, and α denotes an angle between a direction of the orthogonal projection of the light-receiving device onto the target object and a light-receiving direction of the light-receiving device.

2. The image capturing apparatus according to claim 1 , wherein:

the output period has a value obtained by dividing the length in the scanning direction of the light-receiving range for the target object by a scanning speed.

3. The image capturing apparatus according to claim 1 , wherein:

each light-receiving device is a one-dimensional sensor having the light-receiving elements arranged in the direction perpendicular to the scanning direction.

4. The image capturing apparatus according to claim 1 , wherein:

each light-receiving device also has light-receiving elements arranged in the scanning direction and performs transfer and synthesis of the electric charge by using temporal delay.

5. The image capturing apparatus according to claim 1 , wherein:

the image capturing apparatus is mounted on a flying object and the scanning direction is a traveling direction of the flying object.

6. The image capturing apparatus according to claim 1 , wherein:

each light-receiving device has an individually set line rate for charge transfer and the light-receiving elements of each light-receiving device have the same line rate.

7. An image capturing method using an image capturing apparatus that captures an image of a target object by optically scanning the target object by moving in a predetermined scanning direction, the method comprising:

accumulating, by each of light-receiving devices arranged on a light-receiving surface of the image capturing apparatus in a direction perpendicular to the scanning direction, an electric charge according to an amount of light received from the target object, where each light-receiving device has a plurality of light-receiving elements in the direction perpendicular to the scanning direction; and

outputting, by an output device, the electric charge accumulated by each light-receiving device regularly at a predetermined output period which is determined in a manner such that the larger the length in the scanning direction of a light-receiving range for the target object, which is covered by the light-receiving device, the longer the output period, wherein:

the length in the scanning direction of the light-receiving range for the target object is represented by:

D=h {tan(θ+α)−tan α}  [Formula 6]

where h denotes a distance obtained by orthogonal projection of each light-receiving device onto the target object, θ denotes an angle of view of the light-receiving device in the scanning direction, and α denotes an angle between a direction of the orthogonal projection of the light-receiving device onto the target object and a light-receiving direction of the light-receiving device.

8. An image capturing circuit for capturing an image of a target object by optically scanning the target object by moving in a predetermined scanning direction, the apparatus comprising:

light-receiving circuits that are arranged on a light-receiving surface of the image capturing apparatus in a direction perpendicular to the scanning direction, where each light-receiving circuit has a plurality of light-receiving elements in the direction perpendicular to the scanning direction and accumulates an electric charge according to an amount of light received from the target object; and

an output circuit that outputs the electric charge accumulated by each light-receiving circuit regularly at a predetermined output period which is determined in a manner such that the larger the length in the scanning direction of a light-receiving range for the target object, which is covered by the light-receiving circuit, the longer the output period, wherein:

the length in the scanning direction of the light-receiving range for the target object is represented by:

D=h {tan(θ+α)−tan α}  [Formula 6]

where h denotes a distance obtained by orthogonal projection of each light-receiving circuit onto the target object, θ denotes an angle of view of the light-receiving circuit in the scanning direction, and α denotes an angle between a direction of the orthogonal projection of the light-receiving circuit onto the target object and a light-receiving direction of the light-receiving circuit.