Abstract: A method of adjusting read-out processing conditions for a radiation image comprises the steps of calculating the maximum image signal level Smax and the minimum image signal level Smin of a desired image information range from image signals for condition adjustment which represent a radiation image, and adjusting the read-out processing conditions on the basis of the maximum image signal level Smax and the minimum image signal level Smin thus calculated. At least one of the maximum image signal level Smax and the minimum image signal level Smin is determined on the basis of a difference histogram of the image signals for condition adjustment.

Abstract: A radiation image recording apparatus comprises a mobile case, a radiation source connected with the case, and a cassette holding section provided at a part of the case for releasably holding a cassette capable of housing a stimulable phosphor sheet therein. A first magazine holding section is provided inside of the case for releasably holding a sheet housing magazine capable of housing image-recorded stimulable phosphor sheets therein, and a second magazine holding section is provided inside of the case for releasably holding a sheet feed magazine capable of housing stimulable phosphor sheets usable for image recording therein and taking the stimulable phosphor sheets one by one out of the sheet feed magazine. A sheet conveyance system is provided for conveying the stimulable phosphor sheet taken out of the cassette into the first magazine holding section, and conveying the stimulable phosphor sheet usable for image recording taken out of the second magazine holding section into the cassette.

Abstract: A radiation image recording and read-out apparatus comprises a circulation transfer means for transferring a stimulable phosphor sheet along a predetermined circulation path; an image recording section which is disposed in the circulation path and in which a radiation image of an object is recorded on the stimulable phosphor sheet by exposing the stimulable phosphor sheet to radiation passing through the object; an image read-out section which is disposed in the circulation path for scanning the stimulable phosphor sheet with stimulating rays and detecting light emitted from the stimulable phosphor sheet to obtain an image signal; and an erasing section which is disposed in the circulation path and releases residual radiation energy in the stimulable phosphor sheet before the stimulable phosphor sheet is returned to the image recording section. The radiation image recording and read-out apparatus further includes a radiation quality changing filter for changing the quality of the radiation.

Abstract: Stimulable phosphor sheets are circulated through an image recording section for recording radiation images on the stimulable phosphor sheets, an image read-out section for scanning the stimulable phosphor sheets by stimulating rays and detecting light emitted thereby upon stimulation, and a erasing section for releasing radiation energy remaining on the stimulable phosphor sheets after read-out. The recording section is provided with at least two slits positioned such that at least one slit is located on either side of the object and drive means for synchronously driving the slits, whereby it is possible to obtain recorded radiation images free from the effect of scattered radiation.

Abstract: A radiation image read-out apparatus comprises a system for scanning a stimulable phosphor sheet carrying a radiation image stored thereon with stimulating rays in a main scanning direction, a system for moving the stimulable phosphor sheet with respect to the stimulating rays in a sub-scanning direction, and a photodetector for detecting light emitted by the stimulable phosphor sheet when it is exposed to stimulating rays. A stored energy signal output device receives information on the level of radiation energy stored on the stimulable phosphor sheet, and generates a signal corresponding to the information. The radiation dose at image recording is used to provide the information on the level of stored energy. A stimulation energy adjuster receives the signal generated by the stored energy signal output device, and adjusts the level of stimulation energy of stimulating rays per unit area of the stimulable phosphor sheet based on the signal.

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 a photodetector to obtain image signals. The detection range of the photodetector for the emitted light is adjusted to a range substantially wider than an expected light emission range. The image signals obtained with the detection range by the photodetector is stored in a storage device, and sent to a histogram analysis device for creating a histogram of the image signals and analyzing image input information on the stimulable phosphor sheet based on the histogram.

Abstract: A radiation image recording and read-out apparatus comprises a case housing a stimulable phosphor sheet and having an opening, a light shielding cover housed in the case for projection therefrom through the opening, a recording section for exposing the stimulable phosphor sheet disposed at an exposure position in the light shielding cover projected out of the case to radiation, and a read-out section having a sub-scanning system for moving the stimulable phosphor sheet between the exposure position and a position in the case. Or, the apparatus comprises a case having an opening for passing the stimulable phosphor sheet therethrough, a recording section for exposing the stimulable phosphor sheet disposed at the exposure position in the case to radiation, and a read-out section having a sub-scanning system for moving the stimulable phosphor sheet between the exposure position and a position projected out of the case.

Abstract: A method of recognizing a subdivision pattern of radiation images comprises the steps of, in the case where subdivision image recording has been carried out by exposing each of a plurality of predetermined subdivisions on a stimulable phosphor sheet to radiation, detecting prospective edge points, which are considered to be an edge of a subdivision line between the subdivisions, from image signals detected from a stimulable phosphor sheet region as the boundary between the subdivisions, and discriminating whether the prospective edge points stand or do not stand in a straight line. An image subdivision pattern on the stimulable phosphor sheet is recognized by judging that the subdivision line is present in the case where the prospective edge points stand in a straight line, and judging that no subdivision line is present in the case where the prospective edge points do not stand in a straight line.

Abstract: In energy subtraction processing, two or more stimulable phosphor sheets are used to record radiation images of an object which includes bone image and soft tissue image, and a difference signal for forming an image wherein the bone image or the soft tissue image is erased is obtained from the radiation images. The image quality of the energy subtraction image is improved by using the difference signal for picture elements at the portion where the bone image or the image of the soft tissue of a thickness of a predetermined value or larger is present, and by using the original image signal detected from the stimulable phosphor sheets for picture elements at the other portions.

Abstract: Predictive errors are grouped into a plurality of quantizing ranges, and the predictive errors in the respective quantizing ranges are represented by representative quantizing values assigned respectively to the quantizing ranges. The predictive error data items in each of the quantizing ranges are processed to provide a weighted mean value based on the frequency distribution thereto. The weighted mean value or a value close thereto is used as a representative quantized value for that quantizing range.

Abstract: An image signal processing method for storing a series of image signals, which are arrayed in the array sequence of scanning lines on an image, on a recording medium or transmitting the image signals to a receiving device, and reproducing the image from the stored or transmitted image signals comprises the steps of dividing the series of the image signals into predetermined units in the course of storing or transmitting the series of the image signals, and storing or transmitting the image signals by changing the sequence of the respective units so that the units which were adjacent to each other do not adjoin each other. The image is reproduced by rearranging the units in the original sequence in the course of image reproduction.

Abstract: A built-in type radiation image and read-out apparatus comprises a circulating and conveying means for repeatedly conveying stimulable phosphor sheets through an image recording section, an image read-out section and an erasing section. The image recording section has a transfer means for adjusting the distance between an object support member and a stimulable phosphor sheet retainer, whereby recording of enlarged radiation image is possible.

Abstract: A method of compressing image signals comprises the step of dividing the image signals into main signals sampled at appropriate intervals and interpolation signals other than the main signals. As for said main signals, prediction encoding compression processing is carried out between the main signals. As for the interpolation signals, prediction encoding compression processing is carried out based on the main signals. At least for the interpolation signals, quantization processing for making the bit resolution coarse is carried out in the course of encoding. The quantization processing of the interpolation signals is carried out for making the bit resolution coarser than the bit resolution of the main signals.

Abstract: In energy subtraction processing, a high energy image signal SH and a low energy image signal SL are detected from two sets of stimulable phosphor sheets respectively carrying a high energy image and a low energy image of the same object stored thereon. A difference signal Ssub for forming an image of a specific structure of the object is calculated as Ssub=a.multidot.SH-b.multidot.SL+c. The value c is adjusted to a value calculated as c=m.multidot.Smax+n.multidot.Smin-a(m.multidot.SHmax+n.multidot.SHmin)+b(m .multidot.SLmax+n.multidot.

Abstract: A radiation image read-out apparatus is constituted for scanning a stimulable phosphor sheet carrying a radiation image stored thereon with a beam of stimulating rays which cause the stimulable phosphor sheet to emit light in proportion to the stored radiation energy, and photoelectrically detecting the light emitted by a stimulable phosphor sheet portion scanned with the beam of stimulating rays by use of a photodetector to obtain an image signal. The radiation image read-out apparatus is constituted so that the beam diameter of the beam of stimulating rays is adjusted to be smaller than a picture element size and each of picture elements is scanned by a plurality of scanning passes with the beam of stimulating rays. An addition device is provided for adding a plurality of image signals per picture element obtained by the plurality of scanning passes.

Abstract: In a method of and apparatus for quantizing image signals, an image is divided into a plurality of minute unit regions in the course of quantization of image signals. The image signals in the respective minute unit regions are quantized by applying a plurality of such quantization characteristics that the numbers of levels after quantization are approximately equal to each other and positions of quantization steps are deviated from each other in the quantization width direction. The quantization characteristics are changed over for the respective minute unit regions.

Abstract: An electrodynamic transducer comprising a source of magnetic flux and poles that define an annular gap in the flux path to obtain a radially oriented and uniformly distributed magnetic flux across the gap. Coils are mounted on a support that pivots universally about a center concentric with the gap. The coils are placed on the support so that pivotal movement of the latter causes a change in flux linkage with the coils. The coils are wound in such a manner that the electric potentials generated in diametrically opposite coils are added together. There may be sets of mutually perpendicular coils.

Abstract: A pickup cartridge having a vibrating member including a cantilever arm with a reproducing stylus and a permanent magnet, an elastromeric damping member formed into a come or the like shape for supporting the vibrating member as its fulcrum, and a holder supporting the damping member.