JP2582560B2 - Radiation image information reading and reproducing device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention uses the same scanning system to read radiation image information stored and recorded on a stimulable phosphor sheet and reproduce the read image information on a recording sheet. The present invention relates to a radiation image information reading and reproducing apparatus for performing the above.

(Prior art) Radiation (X-ray, α-ray, β-ray, γ-ray,
(Electron beam, ultraviolet rays, etc.), a part of this radiation energy is accumulated in the phosphor, and when this phosphor is irradiated with excitation light such as visible light, the phosphor is stimulated according to the accumulated energy. It is known that the phosphor emits light, and a phosphor exhibiting such properties is called a stimulable phosphor (stimulable phosphor).

Using this stimulable phosphor, radiation image information of a subject such as a human body is temporarily recorded on the stimulable phosphor in a sheet form, and the stimulable phosphor sheet is scanned with excitation light such as a laser beam to excite. Generates emitted light, obtains an image signal by photoelectrically reading the obtained stimulated emission light, and outputs a radiation image of the subject as a visible image to a recording material such as a photographic photosensitive material or a CRT based on the image signal. The present applicant has already proposed a radiation image information recording / reproducing system for causing this to occur. (Japanese Patent Laid-Open No. 55-
No. 12429, No. 56-11395, No. 55-163472, No. 56-1046
No. 45 and No. 55-116340. The image information stored and recorded on the stimulable phosphor sheet in the above-described system deflects the excitation light in the reading device to cause the stimulable phosphor sheet to scan the stimulable phosphor sheet and perform relative scanning of the stimulable phosphor sheet and the excitation light. In the sub-scanning direction, the entire surface of the stimulable phosphor sheet is scanned by the excitation light, and the photostimulated light emitted from the scanning position is read out by photoelectrically detected by the photodetector.

On the other hand, the read image information is recorded on a recording sheet conveyed relatively in the sub-scanning direction by causing a light beam modulated on the basis of the image signal obtained by the reading device to perform main scanning. Is reproduced as a visible image. Therefore, in the conventional system, in order to form a final visible image of the radiation image information recorded on the stimulable phosphor sheet on the recording sheet, in addition to the imaging device, a reading device that reads at least image information and Thus, two reproducing apparatuses for recording image information on a recording sheet are required.

In recent years, various improvements have been made to the radiation image information recording / reproducing system based on a request to simplify the entire system as much as possible, to reduce the size of the entire device, and to reduce the manufacturing cost. Therefore, it has been proposed by JP-A-58-184677 to integrate a conventional reading device and a reproducing device, which both perform scanning with a light beam, so that reading and reproducing are performed by the same scanning system. It is extremely effective in converting

(Problems to be Solved by the Invention) When the reading device and the reproducing device are integrated as described above, a light beam that has passed through the same optical system is used as scanning light both at the time of reading and at the time of peaking. The beam diameter of the light beam on the surface to be scanned (the stimulable phosphor sheet or the recording sheet) at the time and during the reproduction may not be a preferable diameter at any time. That is, at the time of reading, there is an optimum beam diameter of the excitation light according to the image information stored and recorded on the stimulable phosphor sheet, and at the time of reproduction, the optimum beam diameter of the recording light according to the image information to be reproduced and the type of the recording sheet. There is a beam diameter, and a light beam passing through the same optical system may not have an optimum beam diameter as reading light or recording light. In particular, when the same light source is used as the light source for the reading light and the reproduction light, the scanning light always has the same beam diameter on the surface to be scanned. It is an object of the present invention to provide an apparatus capable of performing scanning with a light beam having an optimum beam diameter during reproduction.

(Means for Solving the Problems) In order to achieve the above object, a radiation image information reading / reproducing apparatus of the present invention is a radiation image information reading / reproducing apparatus in which a radiation image information reading apparatus and a reproducing apparatus are integrated. A deflecting device for deflecting a light beam to cause a radiation image of a subject to be accumulated and recorded on a stimulable phosphor sheet or a recording sheet for reproducing the radiation image, and a deflector for performing main scanning, the stimulable phosphor sheet or the recording sheet And a sub-scanning unit that relatively moves the light beam in a direction substantially perpendicular to the main scanning direction, a light detection unit that detects stimulated emission light emitted from the stimulable phosphor sheet by scanning the light beam, and When the light beam scans the stimulable phosphor sheet and scans the recording sheet, the light beam selectively enters and exits the optical path of the light beam, and the beam diameter of the light beam It is characterized in that the beam diameter on the recording sheet is provided with a beam diameter adjusting means for varying to be larger as compared to the beam diameter on the stimulable phosphor sheet.

Note that the same light source may be used as the light beam for reading and recording at the time of reading, or the reading and recording light sources may be separately provided to switch the light beam.

Further, the beam diameter adjusting means may cause a single means to enter and exit the optical path of the light beam at the time of reading and at the time of reproduction, or a plurality of beam diameter adjusting means may be provided. The adjusting means in the optical path may be replaced by entering and exiting the optical path of the light beam.

(Operation) The radiation image information reading and reproducing apparatus according to the present invention includes a reading apparatus and a reproducing apparatus which are conventionally provided independently of each other.
By performing reading and recording together by using one scanning system, and integrating the reading and reproducing of image information by one device, the entire system can be simplified as compared with the conventional system. Can be reduced in size. Further, in this apparatus, the optical elements such as the deflecting means and the scanning lens can be shared for reading and recording, so that the manufacturing cost of the entire system can be reduced.

In addition, according to the apparatus of the present invention, the provision of the beam diameter adjusting means allows the beam diameter of the light beam on the surface to be scanned to be changed between the reading time and the reproducing time so that the beam diameter on the recording sheet becomes the accumulative fluorescent light. The beam diameter can be changed so as to be larger than the beam diameter on the body sheet, and good image information can be read and reproduced with a light beam having the optimum beam diameter for reading and reproduction.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 are side views respectively showing the outline of reading and reproducing image information of the radiation image information reading and reproducing apparatus according to one embodiment of the present invention. First, reading of image information using this apparatus will be described with reference to FIG.

A light beam 2 emitted from a beam light source 1 such as a He-Ne laser light source passes through a modulator 3 provided on an optical path and then rotates as a deflector rotating in a direction indicated by an arrow in FIG.
Is reflected and deflected. At the time of reading, the modulator 3 is stopped from driving, and the light beam 2 always enters the rotary polygon mirror 4 with a constant light amount. On the other hand, below the rotary polygon mirror 4, the stimulable phosphor sheet 7 on which the radiation image information is accumulated and recorded is conveyed in the direction of arrow A and sub-scanned by the endless belt device 6 as sub-scanning means. The light beam 2 reflected and deflected by the rotary polygon mirror 4 as described above passes through a scanning lens 5 such as an fθ lens provided on the optical path, is focused, and is sub-scanned on the stimulable phosphor sheet 7. The main scanning is repeatedly performed in the direction perpendicular to the plane of FIG. 1 substantially perpendicular to the direction, and the entire surface of the stimulable phosphor sheet 7 is two-dimensionally scanned by the light beam 2.

The light beam 2 acts as excitation light on the stimulable phosphor sheet 7, and the stimulable phosphor sheet 7 illuminated with the light beam 2 is scanned by the light beam 2.
Stimulated light is emitted in accordance with the image information stored and recorded therein. This emitted light (not shown) is provided in the vicinity of the stimulable phosphor sheet in a transparent collector having an incident end face 8a arranged parallel to the main scanning line. Enter the light body 8. The light collector 8 is formed such that a front end 8b located near the stimulable phosphor sheet 7 is formed in a flat plate shape, and gradually becomes cylindrical toward the rear end sum. The photomultiplier 9 is formed into a cylindrical shape and is coupled to the photomultiplier 9 as a photodetector. The photostimulated light emitted from the incident end face 8a is condensed at the rear end 8c and received by the photomultiplier 9. In the photomultiplier 9, the photostimulated light is converted into an electric signal, and the obtained electric signal is converted into an image information processing circuit 10.
And is subjected to image processing. Incidentally, when performing the reading, the light beam 2 with respect to the scanning lens 5 as shown is incident as parallel light, arranged from the stimulable phosphor sheet 7 separated by their focal length f ₅ scan The lens 5 focuses the light on the stimulable phosphor sheet 7 so as to minimize the beam diameter.

When the reading of the image information is completed, in order to reproduce the read image information, a recording sheet 11 such as a photographic photosensitive film or photographic paper is conveyed in the direction of arrow A by the endless belt device 6 as shown in FIG. Is done. When reproducing image information on the recording sheet 11, the modulator 3 is driven based on the image information read earlier to modulate the light beam 2. The modulated light beam 2 is reflected and deflected by the rotary polygon mirror 4 and repeatedly main-scans using the recording sheet 11 which is sub-scanned in the direction of arrow A as recording light, and the entire surface of the recording sheet 11 is covered with the stimulable phosphor sheet 7. And reproduces the image information read from.

By the way, in the present apparatus, it is required that the beam diameter of the light beam 2 be larger at the time of reproduction than at the time of reading.
Therefore, the present apparatus is provided with a beam diameter adjusting means 12 composed of a concave lens and using the incident light beam 2 as divergent light. The beam diameter adjusting means 12 retreats from the optical path of the light beam 2 at the time of reading image information as shown in FIG. 1, and the modulator 3 and the rotating polygonal surface at the time of reproducing image information as shown in FIG. The light beam 2 enters between the mirrors 4 on the optical path. In this way, the beam diameter adjusting means 12 is selectively arranged on the optical path of the light beam only at the time of reproduction, so that the light beam slightly diverged enters the rotary polygon mirror 4 only at the time of reproduction, and this light beam is reflected and deflected. , Scanning lens 5
Therefore, the light beam 2 is incident on the recording sheet 11 at a position before the focusing position, so that the light beam 2 has a larger beam diameter on the recording sheet 11 than on the stimulable phosphor sheet 7. Therefore, at the time of reproduction, scanning can be performed with a light beam having a larger beam diameter than at the time of reading. It goes without saying that the type and arrangement of the lens used as the beam diameter adjusting means may be determined according to the optimum beam diameter at the time of reproduction.

As described above, in the present apparatus, reading of image information on the stimulable phosphor sheet and reproduction of image information on the recording sheet can both be performed using one scanning system. The whole system can be simplified as compared with the case, and the size and cost of the whole system can be reduced. further,
According to the present apparatus, by providing the beam diameter adjusting means, the beam diameter of the light beam at the time of reading and at the time of reproduction is increased so that the beam diameter on the recording sheet is larger than the beam diameter on the stimulable phosphor sheet. The reading and the reproduction can be performed by the scanning light having the optimum beam diameter.

Note that the beam diameter adjusting means is not necessarily limited to a single means that is inserted into or taken out of the optical path. A plurality of beam diameter adjusting means are prepared and the beam diameter adjusting means is switched between reading and reproducing. You may do so. In other words, the diameter of the focused beam on the scanning surface can be adjusted by changing the thickness of the light beam 2 incident as parallel light on the scanning lens 5, and as a beam diameter adjusting means as shown in FIG. And two beam expanders 22A and 22B for changing the incident light beam 2 to different thicknesses and emitting the same, respectively.
2B may be replaced on the optical path at the time of reading and at the time of reproducing. When it is desired to increase the beam diameter during reproduction, a beam expander 22B having a relatively small beam diameter expansion amount is selected during reproduction as shown in FIG. 3A, and as shown in FIG. 3B during reading. Thus, the beam expander 22A having a relatively large beam diameter expansion amount may be selected. At this time, as shown in FIG. 4, two beam expanders 22A and 22B are mounted on a disk-shaped holder 23, and
The beam expander 22A,
It is convenient if the 22Bs are alternately positioned in the optical path of the light beam and the switching is performed. Further, the number of beam diameter adjusting means may be three or more, and an optimum one may be selected and used for reading and reproducing.

The specific configuration of the beam diameter adjusting means is not limited to the one described in the above embodiment, but selectively enters and exits the optical path of the light beam at the time of reading and reproduction, and determines the beam diameter on the scanning surface of the light beam on the recording sheet. Any material can be used as long as the upper beam diameter can be changed so as to be larger than the beam diameter on the stimulable phosphor sheet.

Further, the apparatus of the present invention is not limited to the apparatus using the same light source at the time of reading and at the time of reproducing as described above, and has a reading beam light source and a reproducing beam light source independently of each other. By switching the optical path of the light beam emitted from the beam light source, a light beam having a beam diameter such that the beam diameter on the recording sheet becomes larger than the beam diameter on the stimulable phosphor sheet during reading and reproduction, respectively. The apparatus may be configured to guide the same scanning optical system. FIG. 5 shows an example of an apparatus provided with a reading beam light source and a reproducing beam light source independently.

The device shown is a He-Ne laser as a reading beam light source.
1A is provided with a semiconductor laser 1B as a reproducing beam light source, respectively, and emitted from both lasers in directions orthogonal to each other, on the optical path of laser light 2A as reading light and laser light 2B as reproducing light, A dichroic mirror 30 that transmits light in the wavelength region of the laser light 2A, reflects light in the wavelength region of the laser light 2B, and guides both laser lights to the same optical path is provided. On the common optical path of the laser beams 2A and 2B, an arbitrary beam diameter adjusting means 32, a rotary polygon mirror 4, and a scanning lens (not shown) similar to those of the above-described embodiment are provided. A shutter 31 is provided between the He-Ne laser 1A and the dichroic mirror 30 so as to enter and exit the optical path of the laser light 2A.

At the time of reading, the shutter 31 is a laser beam 2A indicated by a broken line in the figure.
And the laser beam 2A is made incident on the dichroic mirror, and the output of the semiconductor laser 1B is turned off. At this time, the beam diameter adjusting means 32 has retreated to the position shown by the broken line in the figure. On the other hand, at the time of reproduction, the shutter 31 enters the optical path of the laser light 2A and cuts the laser light 2A, and the semiconductor laser 1B is directly modulated based on the read image information and outputs the laser light 2B according to the image information . Further, a beam diameter adjusting means 32 is made to enter the optical path of the laser beam 2B reflected by the dichroic mirror 30 as shown by a solid line in the figure, and the beam diameter of the laser beam 2B on a recording sheet (not shown) is reduced. Make an adjustment to increase it. Providing the reading beam light source and the reproducing beam light source in this way is particularly useful when it is desired to change the wavelength or output of the scanning light between reading and reproducing.

(Effects of the Invention) As described above, according to the radiation image information reading and reproducing apparatus of the present invention, the conventional reading apparatus and reproducing apparatus can be read and reproduced by using the common scanning system to read and reproduce the image information. The entire system can be integrated without increasing the size of the entire device, and the entire system can be reduced in size. Also, only one scanning means such as a deflector and a sub-scanning means needs to be provided for reading and reproducing, and the manufacturing cost can be greatly reduced.

In addition, according to the apparatus of the present invention, the provision of the beam diameter adjusting means enables the beam diameter of the light beam on the scanning surface to be changed between the recording sheet and the stimulable phosphor sheet during reading and reproduction. The reading and the reproduction can be performed by the scanning light having a beam diameter suitable for each of them, so that the beam diameter is changed to be larger than the beam diameter.

[Brief description of the drawings]

1 and 2 are side views showing a radiation image information reading apparatus according to one embodiment of the present invention, and FIGS. 3 (a) and 3 (b) show main parts of the apparatus according to another embodiment of the present invention. FIG. 4 is a perspective view showing a beam diameter adjusting means in the apparatus shown in FIG. 3, and FIG. 5 is a plan view showing a main part of an apparatus according to still another embodiment of the present invention. 2 ... light beam 3 ... modulator 4 ... rotating polygon mirror 6 ... endless belt device 7 ... storage phosphor sheet 9 ... photomultiplier 11 ... recording sheet 12 beam diameter adjusting means 22A, 22B …… Beam expander

Claims (1)

(57) [Claims] 1. A radiation image information reading / reproducing apparatus in which a radiation image information reading apparatus and a reproducing apparatus are integrated, wherein a stimulable phosphor sheet on which a radiation image of a subject is accumulated and recorded by deflecting a light beam. Or a deflector for performing main scanning on a recording sheet for reproducing the radiation image, a sub-scanning unit for relatively moving the stimulable phosphor sheet or the recording sheet and the light beam in a direction substantially perpendicular to the main scanning direction,
A light detecting unit that detects stimulated emission light emitted from the stimulable phosphor sheet by scanning the light beam, and a case where the light beam scans the stimulable phosphor sheet and a case where the recording sheet is scanned. And a beam diameter adjusting means for selectively changing the beam diameter of the light beam into and out of the optical path of the light beam so that the beam diameter on the recording sheet is larger than the beam diameter on the stimulable phosphor sheet. Radiation image reading and reproducing apparatus.