Abstract: A method of and apparatus for processing a radiographic image in a radiographic image copying system in which an original radiograph scanned with the light beam and the image information of the radiograph is read out by a detector which gives an output to be processed and used for reproducing an image on a recording material. In the processing of the detected output, an operation represented by a formulaD'=Dorg+.beta.(Dorg-Dus)is conducted, where Dorg is the original image density detected by the detector, .beta. is an emphasis coefficient, and Dus is an unsharp mask density corresponding to a super-low spatial frequency at every scanning point. The unsharp masking process may be performed together with a gradation process, reduction of image size, smoothing process and the like. Further, the emphasis coefficient may be varied with either the original image density Dorg or the unsharp mask signal Dus.

Abstract: A method and apparatus for processing a radiation image in a radiation image recording system in which a stimulable phosphor is stimulated with a scanning stimulating beam and the light emitted from the stimulable phosphor upon stimulation by the stimulating beam is detected by a detector which generates an output which is processed and used for recording a visible image on a recording material. In the processing of the detected output, an operation represented by a formulaS'=Sorg+.beta. (Sorg--Sus)is conducted, where Sorg is the original image signal detected by the detector, .beta. is an emphasis coefficient, and Sus is an unsharp mask signal corresponding to a super-low spatial frequency at every scanning point. The unsharp masking process may be performed together with a gradation process, reduction of image size, smoothing process and the like. Further, the emphasis coefficient may be varied with either the original image signal Sorg or the unsharp mask signal Sus.

Abstract: A method and apparatus for processing a radiation image in a radiation image recording system in which a stimulable phosphor is stimulated with a scanning stimulating ray and the light emitted from the stimulable phosphor upon stimulation by the stimulating ray is detected by a photodetector which gives an output to be processed and used for recording a visible image on a recording medium. The radiation image of the frontal chest is gradation processed. The gradation processing is characterized in that the density at the boundary of the heart and the lungs of the image on the recording medium is lowered to lower the contrast of the heat and raise the contrast of the lungs.

Abstract: A method and apparatus for processing a frontal chest radiograph in a radiographic image copying system in which an original radiograph is scanned with a scanning light beam and the light transmitted through the radiograph is detected by a photodetector which gives an output to be processed and used for recording a visible image on a recording medium. The frontal chest radiograph is gradation processed. The gradation processing is characterized in that the density at the boundary of the heart and the lungs of the image on the recording medium is lowered to lower the contrast of the heart and raise the contrast of the lungs.

Abstract: A method and apparatus for processing a radiation image in a radiation image recording system in which a stimulable phosphor is stimulated with a scanning stimulating ray and the light emitted from the stimulable phosphor upon stimulation by the stimulating ray is detected by a photodetector which gives an output to be processed and used for recording a visible image on a recording medium. The radiation image of the frontal chest is gradation processed. The gradation processing is characterized in that the density between the densities of the spine and the heart of the image on the recording medium is lowered to lower the contrast of the spine and raise the contrast of the heart and the lungs.

Abstract: In a radiation image recording system in which a radiation image is once recorded in a stimulable phosphor and then read out and reproduced on a recording material, the gradation of the radiation image is processed to enhance the diagnostic efficiency and accuracy of the image. The radiation image is read out by scanning the stimulable phosphor by a stimulating ray to cause the phosphor to emit light of the amount corresponding to the radiation energy stored in the phosphor. The emitted light is detected and converted to an electric signal. The level of the electric signal is converted in such a way that the maximum level of the signal corresponding to the maximum density of the radiation image is converted to a level resulting in the optical density of 1.5 to 2.8 in the reproduced image on a recording material and the minimum level corresponding to the minimum density is converted to a level resulting in the optical density of fog density of the recording material to fog density plus 0.

Abstract: In Reiss chamber method or ionography, or in a method of modification or combination of these methods wherein an electrostatic latent image of an object irradiated with radiations such as X-rays is formed on an insulating image recording layer, a photoconductive material is used as the image recording layer. The charge carried on the photoconductive image recording layer is partly neutralized by the radiations received thereby. In an embodiment, a fluorescent layer is attached to the photoconductive image recording layer to accelerate the neutralization of the charge when the recording layer is exposed to the radiations. In another embodiment, the photoconductive material has a property that the photoconductivity increases as the strength of an electric field applied thereacross increases, and the image recording layer made of such a photoconductive material is uniformly exposed to light simultaneously with or after the irradiation of the radiations.