Abstract: In a method of recording a radiation image by use of a stimulable phosphor in which the stimulable phosphor is first exposed to an imagewise radiation to store the energy of the radiation and then is exposed to stimulating rays to emit light in accordance with the energy stored therein, the instantaneous emission of light emitted upon exposure of the stimulable phosphor to the radiation is detected to measure the level of the energy of the radiation stored in the phosphor. The instantaneous emission is detected by a photosensor which is located behind the phosphor. The output of the photosensor is utilized to control the density and/or contrast of the final image recorded on a photographic film which is recorded by use of the light emitted by the phosphor upon stimulated.

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: A barium fluorohalide phosphor represented by the formulaBaFX:xCe,yAwherein X is at least one halogen selected from the group consisting of chlorine, bromine and iodine, A is at least one metallic element selected from the group consisting of indium, thallium, gadolinium, samarium and zirconium, and x and y are numbers satisfying the conditions of 0<x.ltoreq.2.times.10.sup.31 1 and 0<y.ltoreq.5.times.10.sup.-2, respectively. The phosphor emits stimulated light of higher luminance than the conventional cerium activated barium fluorohalide phosphor when stimulated by light of wavelength ranging from 450 to 800 nm after exposure to ionizing radiations such as X-rays or .gamma.-rays, ultraviolet rays, cathode rays, or the like. Further, the phosphor emits spontaneous light of high luminance when excited by ionizing radiations, ultraviolet rays, cathode rays, or the like.

Abstract: A radiation image recorded in a stimulable phosphor sheet or plate is visualized by stimulating the phosphor with stimulating rays. Being stimulated by the stimulating rays, the phosphor emits detectable light. The emitted light is detected by a photodetector. The wavelength of the stimulating rays is selected within the range of 600 to 700 nm. The wavelength of the light detected by the photodetector is selected within the range of 300 to 500 nm.

Abstract: A radiation image is recorded on a stimulable phosphor and the recorded image is reproduced by utilizing the stimulability of the phosphor. As the phosphor is used an alkaline earth metal fluorohalide phosphor having high stimulability represented by the formula(Ba.sub.1-x M.sub.x.sup.II)FX:yAwherein M.sup.II is at least one divalent metal selected from the group consisting of Mg, Ca, Sr, Zn and Cd, X is at least one halogen selected from the group consisting of Cl, Br and I, A is at least one element selected from the group consisting of Eu, Tb, Ce, Tm, Dy, Pr, Ho, Nd, Yb and Er, and x and y are numbers satisfying the conditions of 0.ltoreq.x.ltoreq.0.6 and 0.ltoreq.y.ltoreq.0.2.

Abstract: A radiation image is recorded on a stimulable phosphor, and the recorded image is reproduced by utilizing the stimulability of the phosphor. As the phosphor is used at least one of the following phosphors.(a) a copper and lead activated zinc sulfide phosphor ZnS:Cu,Pb).(b) a phosphor included in a group of europium activated barium aluminate phosphors represented by the formulaBaO.xAl.sub.2 O.sub.3 :Euwherein x is a number satisfying the condition of 0.8.ltoreq.x.ltoreq.10.(c) a phosphor included in a group of divalent metal silicate phosphors represented by the formulaM.sup.II O.ySiO.sub.2 :Awherein M.sup.II is at least one divalent metal selected from the group consisting of Mg, Ca, Sr, Zn and Ba, A is at least one element selected from the group consisting of Ce, Tb, Eu, Tm, Pb, Tl, Bi and Mn, and y is a number satisfying the condition of 0.5.ltoreq.y.ltoreq.2.5.

Abstract: A rear projection screen comprising a wax and a wax reforming agent which is miscible with the wax and is present in an amount effective to increase the mechanical strength and adhesiveness of the wax.

Abstract: Rear projection screens of superior mechanical and optical properties are described which comprise, in all instances, at least one light diffusion layer and at least one transparent support, an intermediate layer being provided between the light diffusion layer and the transparent support, which intermediate layer is formed from a photocurable composition.

Abstract: A rear projection screen having means for controlling light direction comprising a light diffusion plate composed of wax, a crystalline polymer or a mixture thereof, and light shielding layers contained in the light diffusion plate which are parallel to the direction of image projection.

Abstract: A rear projection screen produced by providing surface irregularity directly on at least one side of a light diffusion layer containing at least one light scattering material selected from the group consisting of one or more waxes, one or more crystalline polymers or a mixture thereof.