Method of and system for obtaining radiation image signal

1 . A method of obtaining a radiation image signal wherein

a stimulable phosphor sheet on which a radiation image has been recorded is conveyed in a sub-scanning direction intersecting a main scanning direction relatively to a simulating light beam while projecting the stimulating light beam thereonto in the main scanning direction,

an exposed area on the stimulable phosphor sheet exposed to the stimulating light beam is imaged on each light receiving portion of a line sensor which is formed by causing a light receiving line to correspond to a sub-scanning corresponding direction which corresponds to the sub-scanning direction, a plurality of light receiving portions each receiving and photoelectrically converting stimulated light emitted from the stimulable phosphor sheet exposed to the stimulating light being arranged in a main scanning corresponding direction which corresponds to the main scanning direction to form the light receiving line,

the stimulated light emitted from the exposed area on the stimulable phosphor sheet is received and photoelectrically converted by each of the light receiving portions thereby obtaining a partial image signal by the light receiving portions which represents the amount of the stimulated light received by the light receiving portion, and

an image signal representing the radiation image recorded on the stimulable phosphor sheet is obtained by summing the partial image signals obtained by the light receiving portions in each light receiving line arranged in the sub-scanning corresponding direction,

characterized in that each of the partial image signals to be summed to obtain the image signal is obtained by photoelectrically converting the stimulated light received by each light receiving portion when the same area on the stimulable phosphor sheet is imaged on the light receiving portions which are arranged in the sub-scanning corresponding direction at different timings due to the relative conveyance of the stimulable phosphor sheet.

2 . A system for obtaining a radiation image signal comprising

a stimulating light projecting means which projects a stimulating light beam in a main scanning direction onto a stimulable phosphor sheet on which a radiation image has been recorded,

a stimulable phosphor sheet conveyor means which conveys the stimulable phosphor sheet relatively to a simulating light beam in a sub-scanning direction intersecting the main scanning direction,

a line sensor means which is formed by causing a light receiving line to correspond to a sub-scanning corresponding direction which corresponds to the sub-scanning direction, a plurality of light receiving portions each receiving and photoelectrically converting stimulated light emitted from the stimulable phosphor sheet exposed to the stimulating light being arranged in a main scanning corresponding direction which corresponds to the main scanning direction to form the light receiving line,

an imaging means which images an exposed area on the stimulable phosphor sheet exposed to the stimulating light beam on each light receiving portion of the line sensor,

a summing means which sums up partial image signals obtained by the light receiving portions in each light receiving line arranged in the sub-scanning corresponding direction, thereby obtaining an image signal representing the radiation image recorded on the stimulable phosphor sheet, and

a control means which causes the summing means to sum up the partial image signals by the use of the partial image signals each of which is obtained by the line sensor and represents the amount of stimulated light which has been emitted from the corresponding exposed area to be received by each light receiving portion through the imaging means and thereby photoelectrically converted while conveying the stimulable phosphor sheet by the stimulable phosphor sheet conveyor means while projecting the stimulating light beam thereonto by the stimulating light projecting means,

characterized in that the control means controls the summing means to sum the partial image signals which are obtained by photoelectrically converting the stimulated light received by each light receiving portion when the same area on the stimulable phosphor sheet is imaged on the light receiving portions which are arranged in the sub-scanning corresponding direction at different timings due to the relative conveyance of the stimulable phosphor sheet.

3 . A system for obtaining a radiation image signal as defined in claim 2 in which the control means is changed with the timing, at which it photoelectrically converts the stimulated light received by each of the light receiving portions to a partial image signal, according to the kind of the stimulable phosphor sheet used and/or the mode in which the image signal is read out from the stimulable phosphor sheet.

4 . A system for obtaining a radiation image signal as defined in claim 2 in which the control means is changed with the timing, at which it photoelectrically converts the stimulated light received by each of the light receiving portions to a partial image signal, on the basis of the partial image signal obtained by the use of a test sample.

5 . A system for obtaining a radiation image signal as defined in claim 2 in which the imaging means images an erected life-size image of the exposed area on the stimulable phosphor sheet on the light receiving portions.

6 . A system for obtaining a radiation image signal as defined in claim 3 in which the imaging means images an erected life-size image of the exposed area on the stimulable phosphor sheet on the light receiving portions.

7 . A system for obtaining a radiation image signal as defined in claim 4 in which the imaging means images an erected life-size image of the exposed area on the stimulable phosphor sheet on the light receiving portions.