Abstract: In a radiation image read-out method wherein preliminary read-out is conducted prior to final read-out for adjusting final read-out conditions and/or image processing conditions for a plurality of stimulable phosphor sheets carrying a radiation image of the same object recorded thereon by combination image recording, the preliminary read-out and the final read-out are conducted only for the first stimulable phosphor sheet which is first subjected to the image read-out, and only the final read-out is conducted for the other stimulable phosphor sheets by use of the read-out conditions and/or image processing conditions adjusted on the basis of the image input information obtained by the preliminary read-out of the first stimulable phosphor sheet.

Abstract: In a method of adjusting read-out conditions for a radiation image stored on a stimulable phosphor sheet by limiting the radiation exposure field, digital image signals at respective positions on the stimulable phosphor sheet for detected on the basis of image information obtained by preliminary read-out. The digital image signals are subjected to a differentiation processing, and the radiation exposure field on the stimulable phosphor sheet is detected by use of the differentiated values obtained thereby. The read-out conditions in final read-out are adjusted on the basis of the image information obtained within the detected radiation exposure field by the preliminary read-out.

Abstract: A radiation image recording and reproducing method comprises the steps of scanning a stimulable phosphor sheet carrying a radiation image stored thereon with stimulating rays, and detecting light emitted by the stimulable phosphor sheet upon stimulation by stimulating rays to obtain an image signal. The image signal including a stimulated light emission signal and an after-glow signal representing a stimulated light emission after-glow emanated by the portion of the stimulable phosphor sheet no longer being exposed to stimulating rays is detected in such a condition that the level of the after-glow signal at a position on the stimulable phosphor sheet 20 mm beyond the position where exposure to stimulating rays is completed is not higher than 10.sup.-2.5 times the level of the stimulated light emission signal, and the level of the after-glow signal at a position 430 mm beyond the position where exposure to stimulating rays is completed is not higher than 10.sup.-3.

Abstract: A radiation image read-out and reproducing apparatus comprises a section for feeding a stimulable phosphor sheet carrying a radiation image stored thereon, a section for feeding a recording sheet, a section for photoelectrically reading ID information, and a light beam scanning section. The light beam scanning section comprises a read-out main scanning system for scanning a light beam in a main scanning direction on the stimulable phosphor sheet, a reproducing main scanning system for scanning a light beam in a main scanning direction on the recording sheet, and a sub-scanning system for moving the stimulable phosphor sheet and the recording sheet in a sub-scanning direction, thereby to read out a radiation image from a stimulable phosphor sheet and to reproduce a radiation image and ID information on a recording sheet by modulating the light beam in the reproducing main scanning system in accordance with a radiation image read out and information detected by the ID information reading section.

Abstract: A radiation image read-out apparatus comprises a light shielding material removal section for removing a light shielding material by dissolution or separation from a stimulable phosphor sheet comprising a stimulable phosphor layer and the light shielding material which is provided at least on a surface on the stimulable phosphor layer side and which is removable by dissolution in a solvent or by physical separation, the stimulable phosphor sheet carrying a radiation image stored on the stimulable phosphor layer. A read-out section is provided for reading out the radiation image by exposing the stimulable phosphor sheet, from which the light shielding material has been removed, to stimulating rays which cause the stimulable phosphor sheet to emit light in proportion to the stored radiation energy, and photoelectrically detecting the emitted light.

Abstract: An accumulative histogram of an image signal bearing a transmitted image of a human body is generated. The rate of change of the accumulative histogram is determined in a predetermined region of the image, and the imaged posture of the image is determined from the rate of change. Alternatively, to determine the imaged posture, the separation of a histogram is determined, or the pattern of the histogram is compared with a plurality of reference histogram patterns. The derivative of second order of a function approximated by the histogram pattern may be checked for its sign, or the histogram may be checked to determine whether it is of a single-peak form or a double-hump form. The dispersion of the histogram may also be determined.

Abstract: A high-speed image recording apparatus comprises a sheet changer for changing a stimulable phosphor sheet at an image recording position, a radiation source drive controller, and a filter changer for changing a radiation filter on a radiation passage between a radiation source and a stimulable phosphor sheet at each image recording step. The sheet changer, the radiation source drive controller and the filter changer are activated by signals sent from a controller to load the stimulable phosphor sheet to the image recording position, to change over the radiation filter, and then to emit radiation to the stimulable phosphor sheet via an object, thereby recording a high energy image and a low energy image of good energy discrimination in stimulable phosphor sheets.

Abstract: In a radiation image read-out method and apparatus, final read-out is carried out for obtaining image signals for use in reproduction of a visible image from a recording medium carrying a radiation image of an object recorded thereon, image processing conditions for use in processing of the final read-out signals obtained by the final read-out are adjusted, and image processing of the final read-out image signals is carried out by use of the image processing conditions. In the case where subdivision image recording is carried out by exposing each of a plurality of subdivisions on the recording medium to radiation in the course of the radiation image recording, image signals at a subdivision, which has not been exposed to the radiation, is removed from the final read-out image signals on the basis of information on subdivision image recording, and the image processing conditions are adjusted on the basis of the remainder of the final read-out image signals.

Abstract: In a radiation image read-out method and apparatus, a stimulable phosphor sheet carrying a radiation image stored thereon is exposed to stimulating rays which cause the stimulable phosphor sheet to emit light in proportion to the stored radiation energy, and the emitted light is photoelectrically detected by use of a light detection device to obtain image signals for use in reproduction of a visible image. Light detection ranges of the light detection device suitable for image recording conditions are stored in conformity with the respective image recording conditions in a memory. In the course of detection of the light emitted by the stimulable phosphor sheet, the image recording conditions with respect to the stimulable phosphor sheet on which image read-out is to be carried out are designated, the light detection range corresponding to the designated image recording conditions is read from the memory, and is set in the light detection device. Preliminary read-out is not used.

Abstract: In a radiation image read-out method and apparatus, a stimulable phosphor sheet carrying a radiation image stored thereon is exposed to stimulating rays which cause the stimulable phosphor sheet to emit light in proportion to the stored radiation energy, and the emitted light is photoelectrically detected. When radiation image read-out is conducted on a stimulable phosphor sheet subjected to subdivision image recording carried out by exposing many subdivisions on the stimulable phosphor sheet respectively to a radiation in radiation image recording, the respective subdivisions are discriminated on the basis of information on subdivision image recording. Conditions of image processing are determined for the respective discriminated subdivisions, and are adjusted for the respective subdivisions when image processing is conducted.

Abstract: In a radiation image read-out method and apparatus, a stimulable phosphor sheet carrying a radiation image stored thereon is exposed to stimulating rays which cause the stimulable phosphor sheet to emit light in proportion to the stored radiation energy, and the emitted light is photoelectrically detected to obtain an image signal representing the radiation image. Stimulating rays are made to pass through a beam diameter adjusting device, and the level of the stored radiation energy is detected. The beam diameter of stimulating rays is expanded by the beam diameter adjusting device as the level of the stored radiation energy decreases. In a radiation image read-out and reproducing method, a photosensitive material is exposed to a recording beam modulated with the read-out image signal for recording the radiation image thereon.

Abstract: In a radiation image read-out apparatus wherein preliminary read-out is ordinarily conucted prior to final read-out for adjusting final read-out conditions and/or image processing conditions for radiation images stored on stimulable phosphor sheets, the preliminary read-out can be omitted and the final read-out and image processing be conducted on the basis of fixed conditions when necessary to obtain reproduced images with the same contrast.

Abstract: A method of measuring an after-glow of a stimulable phosphor sheet comprises the step of detecting an instantaneous light emission after-glow emanated by the stimulable phosphor sheet carrying a radiation image stored thereon by use of a photodetector when the stimulable phosphor sheet is being conveyed toward a system for final read-out after preliminary read-out is finished, thereby measuring the level of the after-glow. A method of adjusting radiation image read-out conditions comprises the steps of creating a histogram of preliminary read-out image signals obtained by preliminary read-out, detecting the instantaneous light emission after-glow by a photodetector, obtaining a signal Sx representing the level of the instantaneous light emission after-glow, and adjusting final read-out conditions and/or image processing conditions based on a value calculated by subtracting the value of the signal Sx from a characteristic value of the preliminary read-out image signals in the histogram.

Abstract: In a radiation image read-out method wherein preliminary read-out is conducted prior to final read-out for adjusting final read-out conditions and/or image processing conditions for a plurality of stimulable phosphor sheets carrying a radiation image of the same object recorded thereon by combination image recording, the preliminary read-out and the final read-out are conducted only for the first stimulable phosphor sheet which is first subjected to the image read-out, and only the final read-out is conducted for the other stimulable phosphor sheets by use of the read-out conditions and/or image processing conditions adjusted on the basis of the image input information obtained by the preliminary read-out of the first stimulable phosphor sheet.

Abstract: Test image information is recorded on a test recording medium and the test recording medium is scanned with a light beam to produce an image signal in each of two modes in which the test recording medium is oriented such that a prescribed line on the test recording medium extends in a main scanning direction and an auxiliary scanning direction substantially normal to the main scanning direction respectively in the two modes. A signal level distribution A(x) is determined along the prescribed line of a signal indicative of a logarithmic function of an output signal from a light detector when the prescribed line extends along the main scanning direction, and a signal level distribution B(x) along the prescribed line of a signal indicative of a logarithmic function of an output signal from the light detector when the prescribed line extends along the auxiliary scanning direction (x indicates a pixel position on the prescribed line).

Abstract: In a radiation image read-out method and apparatus, a stimulable phosphor sheet carrying a radiation image stored thereon is exposed to stimulating rays which cause the stimulable phosphor sheet to emit light in proportion to the stored radiation energy, and the emitted light is photoelectrically detected to obtain an image signal representing the radiation image. Stimulating rays are made to pass through a beam diameter adjusting device, and the level of the stored radiation energy is detected. The beam diameter of stimulating rays is expanded by the beam diameter adjusting device as the level of the stored radiation energy decreases. In a radiation image read-out and reproducing method, a photosensitive material is exposed to a recording beam modulated with the read-out image signal for recording the radiation image thereon.

Abstract: As an X-ray detecting means in an energy subtraction processing method, there is used a composite member comprising a plurality of stimulable phosphor sheets exhibiting different levels of characteristics of absorbing the low energy component of a radiation and overlaid one upon another, or a composite member comprising a plurality of stimulable phosphor sheets and at least one filter made of a material absorbing the low energy component of a radiation which are overlaid one upon another, or a stimulable phosphor sheet comprising a substrate made of a material absorbing the low energy component of a radiation and stimulable phosphor layers provided thereon. The composite member or the stimulable phosphor sheet is exposed to a radiation passing through an object including a specific structure to record therein at least two radiation images between which the image information at the portion of the specific structure is different.

Abstract: A radiation image recording apparatus comprises a radiation source for emitting a radiation to an object, a device for moving the radiation source to change the irradiation angle, a sheet changer for feeding a stimulable phosphor sheet to an image recording position exposed to the radiation passing through the object to have a radiation image of the object stored on the stimulable phosphor sheet and then receiving a drive signal to remove the stimulable phosphor sheet from the image recording position and feed a next stimulable phosphor sheet thereto, and a device for moving the sheet changer so that the stimulable phosphor sheet at the image recording position and the radiation source satisfy the linear rule and the geometric rule with respect to a point within the object or in the vicinity thereof.

Abstract: In a radiation image read-out method and apparatus, final read-out is carried out for detecting image signals for use in reproduction of a visible image from a recording medium carrying a radiation image recorded thereon, and read-out conditions for the final read-out and/or image processing conditions are adjusted based on image signals for condition adjustment detected by reading out the image information recorded on the recording medium. The image signals for condition adjustment are utilized to judge whether the image which the image signals represent has line symmetry or not. The read-out conditions for the final read-out and/or the image processing conditions are adjusted in accordance with the results of the discrimination so that the density of a region concerned in the reproduced visible image is maintained constant regardless of the image recording direction of an object.

Abstract: In a method of adjusting read-out conditions for a radiation image stored on a stimulable phosphor sheet by limiting the radiation exposure field, digital image signals at respective positions on the stimulable phosphor sheet are detected on the basis of image information obtained by preliminary read-out. The digital image signals are subjected to a differentiation processing, and the radiation exposure field on the stimulable phosphor sheet is detected by use of the differentiated values obtained thereby. The read-out conditions in final read-out are adjusted on the basis of the image information obtained within the detected radiation exposure field by the preliminary read-out.