JP4014129B2 - X-ray image reader - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray image reading apparatus for reading an X-ray image held on an X-ray image holding body, for example, an X-ray image holding body having an X-ray holding surface formed by a stimulable phosphor.
[0002]
[Prior art]
An X-ray image carrier formed using a storage phosphor is conventionally known. When X-ray measurement is performed using this X-ray image carrier in order to know the crystal structure of the sample, the sample is irradiated with X-rays, and X-rays generated from the sample at this time, for example, diffraction X The above-mentioned X-ray image holding body is exposed with X-rays, scattered X-rays and the like. As a result, an energy latent image is formed at the coordinate position of the X-ray image holding body corresponding to the diffraction angle at which diffracted X-rays or the like are generated on the X-ray receiving surface of the X-ray holding body.
[0003]
The stimulable phosphor has a property of holding an energy latent image where X-rays have been struck, and when irradiated with stimulating excitation light, for example, laser light, where the energy latent image is held, the energy latent image is stored. Is converted into light and emitted to the outside. Therefore, if the light emitted from the storage phosphor when the storage phosphor holding the energy latent image is irradiated with laser light, the intensity of the X-rays that contributed to the formation of the energy latent image can be increased. I can know. Further, the diffraction angle of X-rays contributing to the formation of the energy latent image can be known from the coordinate position of the stimulable phosphor that has emitted light.
[0004]
As an X-ray image reading apparatus utilizing this principle, the present applicant has proposed a double-head X-ray image reading apparatus 100 as shown in FIG. In this conventional apparatus, the first reading head 101a and the second reading head 101b are arranged at symmetrical positions with an angular interval of 180 °, and the laser light from the output optical system 102 incorporating the laser light source is distributed to provide a first. The light is emitted from both the first read head 101a and the second read head 101b.
[0005]
In addition, the first reading head 101a or the second reading head 101b can take in external light, and the taken-in light is received by the light receiving optical system 103 incorporating the photoelectric converter, and further, the electric power is output by the photoelectric converter. Converted to a signal.
[0006]
When reading the X-ray latent image held on the X-ray image holding body 104 by the X-ray image reading apparatus 100 having this configuration, the X-ray image holding body 104 is arranged in a semi-cylindrical shape and arranged in a first shape. The rotation axis X0 of the read head 101a and the second read head 101b is arranged at a substantially central position of the cylindrical shape of the X-ray image holding member 104. Then, while rotating the first reading head 101a and the second reading head 101b as shown by the arrow A around the axis X0, the entire X-ray image reading apparatus 100 is moved in parallel with the axis X0 as shown by the arrow B. Let
[0007]
By the rotation in the direction of arrow A and the straight movement in the direction of arrow B as described above, the first reading head 101a and the second reading head 101b are alternately carried to the region facing the X-ray image holding body 104, As a result, a wide surface of the X-ray image holding member 104 is scanned. During this scanning, when the laser beam emitted from the first reading head 101a or the second reading head 101b scans the surface of the X-ray holding member 104, and the laser beam scans a portion where the energy latent image exists on the surface, Light is generated from that location.
[0008]
The light is taken into the light receiving optical system 103 through the first reading head 101a or the second reading head 101b, converted into an electric signal, and the light intensity from the X-ray image holding body 104 is individually changed based on the electric signal. It is obtained for each coordinate position. That is, it is sampled. This light intensity corresponds to the intensity of X-rays that contributed to the formation of the energy latent image that is the basis of the light emission. Therefore, the X-ray intensity can be known by measuring the light emission intensity.
[0009]
[Problems to be solved by the invention]
Conventionally, the light intensity data is sampled by connecting an arithmetic circuit to the light intensity output terminal of the light receiving optical system 103 and further supplying a sampling pulse to the arithmetic circuit. The intensity output is extracted for each individual pulse width period of the sampling pulse, and the extracted light intensity data is used as read data for one pixel. In the conventional X-ray image reading apparatus, encoders are provided on the rotation shafts of the first reading head 101a and the second reading head 101b, and the sampling pulses are generated using the pulses output from the encoders. It was.
[0010]
Incidentally, the frequency of the sampling pulse required in the X-ray image reading apparatus according to the present invention is about 312.5 KHz, but an encoder capable of outputting such a high-speed frequency is not commercially available at present. The situation is not freely available. Therefore, in the past, considering that the required frequency is 312.5 KHz, an encoder having a low frequency, that is, a low resolution, is used, and the output pulse of this encoder is doubled, quadrupled,... The sampling pulse is generated in a pseudo manner by multiplying.
[0011]
However, strictly speaking, such a pseudo pulse is not a pulse that is turned ON / OFF at an accurate timing. Therefore, the conventional data sampled based on this pulse cannot be said to be extremely accurate data. there were.
[0012]
Further, when the sampling pulse is generated based on the encoder attached to the rotating shaft of the reading head as in the conventional X-ray image reading apparatus, it is caused by the dimensional error of parts or the assembling error between parts. In many cases, the rotary table of the encoder does not rotate in a perfect circle state, for example, it rotates eccentrically. In this case, it is considered difficult to obtain a pulse having a stable frequency as an output pulse of the encoder.
[0013]
Thus, if the pulse obtained from the encoder is unstable, the sampling pulse will inevitably become unstable, and in this case, the finally obtained sampling data also has low reproducibility, that is, reliability. It had to be low data. In particular, in the case of a double head type device in which two read heads are arranged at 180 ° symmetrical positions as in the conventional device shown in FIG. 10, the read data obtained using these read heads is eccentric. There was a tendency to shift greatly under the influence of.
[0014]
The present invention has been made in view of the above problems, and is capable of reading with high reliability by always generating a stable sampling pulse without being affected by the mechanical error of the read head. The purpose is to be able to obtain data.
[0015]
[Means for Solving the Problems]
To achieve the above Symbol purpose of, X-ray image reading apparatus according to the present invention includes a read head for collecting data from the X-ray image carrier by irradiating the stimulating light to the X-ray image holding member, standards and scan drive means for moving the said reading head for secondary scanning perpendicular main scanning and that of the X-ray image carrier, means for generating a reference pulse position of the read head relative, the reference pulse Sampling pulse generating means for generating sampling pulses, and sampling means for sampling the data collected by the read head in accordance with the sampling pulses, and the scan driving means reads the read data for main scanning. A rotation driving means for rotating the head, and a rotation surface of the reading head by the rotation driving means for sub-scanning. Linear drive means for moving the read head straight in a direction, and the means for generating the reference pulse generates a reference pulse when the rotating read head reaches a predetermined position, and the stimulating excitation light Emits light according to the reference pulse, and the sampling pulse generating means starts generating the sampling pulse after a lapse of a delay time after the generation of the reference pulse, and the sampling pulse generating means A sampling pulse is generated independently of the means.
[0016]
According to the X-ray image reading apparatus having this configuration, the sampling pulse is not generated from an encoder provided on the rotation shaft of the read head, but is obtained from an independent pulse generation source that is not affected by the rotation of the read head. Therefore, a stable sampling pulse can be obtained at all times, and therefore, highly reliable read data can be obtained.
[0017]
In addition, since the timing used as the reference for generating the sampling pulse is provided by the reference pulse generated with reference to the position of the read head, the data sampling timing is determined by the rotation of the read head, that is, the scanning of the X-ray image carrier. There is no worry of getting out of timing.
[0018]
In the following, the X-ray image reading apparatus according to the present invention, the read head can be made providing a plurality, yet in that case, the scanning drive means, the X-ray image of the plurality of read head at different timings The plurality of read heads can be moved to scan the holder.
[0019]
This configuration corresponds to a multi-head method using three or more read heads or a double head method using two read heads. According to the X-ray image reading apparatus having this configuration, high-speed measurement can be performed as compared with the single-head system in which only one reading head is used.
[0020]
When performing such high-speed measurement, if the sampling pulse is unstable as in the prior art, a large error was likely to occur in the measurement result. However, as in the present invention, sampling is performed independently from the scanning movement of the read head. If read pulses are generated, stable read data can be obtained.
[0021]
In the following, the X-ray image reading apparatus according to the present invention, the read head may be two in angular intervals of 180 ° from each other are placed symmetrically to each other.
[0022]
According to the X-ray image reading apparatus having this configuration, the X-ray image holding body is main-scanned by rotating two read heads arranged at symmetrical positions of 180.degree. The line image carrier is sub-scanned, and a large area of the X-ray image carrier can be scanned by two read heads by the main scanning and the sub scanning.
[0023]
In the above X-ray image reading apparatus having a structure using two symmetrically arranged read heads, if the encoder is attached to the rotation shaft of these read heads to generate a sampling pulse, two The positional deviation of the read head from 180 ° greatly causes the sampling pulse to become unstable. On the other hand, if the sampling pulse is generated independently of the rotation of the read head as in the present invention, a stable sampling pulse can always be generated regardless of the operation of the read head.
[0024]
In the following, the X-ray image reading apparatus according to the present invention, means for generating a reference pulse position of the read head as a reference, a turntable mounted on the rotary shaft of the read head which is the rotary drive, the rotary A structure having a photo sensor that outputs a pulse signal in accordance with the rotation of the board can be used. According to this configuration, the reference pulse can always be generated stably in relation to the rotation of the read head.
[0025]
In the following, the X-ray image reading apparatus according to the present invention, means for generating a reference pulse position of the read head as a reference, it is possible to generate the reference pulse at the beginning of each line of the plurality of scan lines. In this way, it is possible to always perform reading under the same conditions for each scanning line, and the reading reliability is further improved.
[0026]
In the following, the X-ray image reading apparatus according to the present invention, the sampling pulse generating means includes oscillation means for oscillating a frequency higher than the frequency of the sampling pulse, dividing the output pulses of the raw oscillating means And a frequency dividing circuit. With this configuration, the frequency of the sampling pulse can be made more accurate.
[0027]
In the following, the X-ray image reading apparatus according to the present invention, the oscillation means is capable of outputting an oscillation frequency of more than 10 times the frequency of the sampling pulse. With this configuration, the frequency of the sampling pulse can be made more accurate.
[0028]
In the following, the X-ray image reading apparatus according to the present invention, the oscillation means can have a crystal oscillator source. Since crystal oscillation source has a very stable oscillation characteristics, be generated a sampling pulse using this, it is possible to obtain highly reproducible, i.e. a very reliable read data.
[0029]
In the following, the X-ray image reading apparatus according to the present invention, the oscillation means to oscillate the 5 MHz, the sampling pulse may be a 312.5 KHz. Setting the 5 MHz pulse to 312.5 KHz can be performed using, for example, a 1/16 frequency divider.
[0030]
In the following, the X-ray image reading apparatus according to the present invention, the X-ray image carrier may be constituted by a phosphor having an X-ray holding surface formed by the stimulable phosphor. In this case, the X-ray reading device includes an emission optical system that supplies the excitation light to the one or more reading heads, and the light emitted from the X-ray image holding body. A light receiving optical system that receives light through the head and outputs an electrical signal corresponding to the light received, and further, the output signal of the light receiving optical system can be sampled by the sampling means. According to the apparatus using this stimulable phosphor, high-speed measurement can be performed.
[0031]
Here, the “storable phosphor” is an energy storage type radiation detector sometimes called a stimulable phosphor, and a stimulable phosphor, for example, BaFBr: Er ²⁺ microcrystal is flexible. It is formed by coating or the like on the surface of a film, a flat film, or other member. This storage phosphor is an object that can store X-rays and the like in the form of energy, and can emit the energy as light to the outside by irradiation of stimulating excitation light such as laser light.
[0032]
That is, when the stimulable phosphor is irradiated with X-rays or the like, energy is accumulated as a latent image inside the stimulable phosphor corresponding to the irradiated portion, and further, the stimulable phosphor such as laser light is emitted. When the excitation light is irradiated, the latent image energy is emitted as light. By detecting the emitted light with a phototube or the like, the diffraction angle and intensity of X-rays that contributed to the formation of the latent image can be measured. This stimulable phosphor has a sensitivity of about 10 to 60 times that of a conventional X-ray film, and further has a wide dynamic range of 10 ⁶ to 10 ⁸ .
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a case where the present invention is applied to a double head type X-ray image reading apparatus which is an example of a multi-head type X-ray image reading apparatus will be described as an example. FIG. 1 shows a cross-sectional structure of a double head type X-ray image reading apparatus 1 according to the present invention.
[0034]
The X-ray image reading apparatus 1 includes a rotating body 4 that is rotatably supported by a machine frame 3 by bearings 2a and 2b. The rotating body 4 can rotate around the axis X0. As shown in FIG. 2A, which is a cross-sectional view taken along the line II-II in FIG. 1, the X-ray image holding body 17 to be read is arranged in a semi-cylindrical shape centering on the axis X0. Is done. Note that the X-ray image holding member 17 has an X-ray light receiving surface formed of a stimulable phosphor.
[0035]
In FIG. 1, the rotating body 4 includes a cylindrical laser beam introducing portion 6 supported by a bearing 2 b, a head portion 7 provided at the upper end of the laser beam introducing portion 6, and an upper surface of the head portion 7. And a cylindrical light guide 8 that is provided and supported by the bearing 2a. As is apparent from FIG. 2, the head portion 7 is formed in a rectangular tube shape in which the horizontal direction perpendicular to the axis X0 is the longitudinal direction. Further, in FIG. 1, the upper end 8a of the light outlet 8 is an opening.
[0036]
One end of the head unit 7 is provided with a first read head H1 having a lens 23a and a lens 24a. In addition, a second read head H2 having lenses 23b and 24b is provided at the other end of the head portion 7. As is apparent from FIGS. 1 and 2, these read heads H1 and H2 are arranged at symmetrical positions with an angular interval of 180 ° from each other. The angle of 180 ° is desirably set as strict as possible. However, when the angle deviates from 180 °, it is desirable to correct the measurement result corresponding to the amount of deviation.
[0037]
In FIG. 1, a beam splitter 18 is disposed inside the head unit 7 and above the laser beam introducing unit 6. The beam splitter 18 rotates integrally with the head unit 7 around the axis line X0. As shown in FIG. 3, the beam splitter 18 is formed by bonding a prism 19 having a triangular cross section and a prism 21 having a trapezoidal cross section at a surface C, and further bonding these prisms to a base 22 by other methods. It is formed by.
[0038]
When light is introduced from the light introduction opening 22 a provided on the base 22, a part of the light is transmitted through the boundary surface C and reflected on the inner side of the triangular prism 19, and provided on the base 22. The light is emitted to the outside through the light outlet opening 22b. This light is directed to the first read head H1 in FIG. In FIG. 3, the other part of the light that has passed through the light introduction opening 22 a is reflected by the boundary surface C, propagates through the trapezoidal prism 21, and is opposite to the above-described outgoing light reflected by the triangular prism 19. To the side. This light is directed to the second read head H2 in FIG.
[0039]
A dichroic mirror 26 a is provided inside the head unit 7 and between the first read head H 1 and the beam splitter 18. A dichroic mirror 26b is provided between the second read head H2 and the beam splitter 18. These dichroic mirrors 26a and 26b transmit light from the beam splitter 18 toward the read head 24a or 24b, and on the other hand, reflect the light taken from the read heads H1 and H2 toward the beam splitter 18 to reflect the light. Head to.
[0040]
The X-ray image reading apparatus 1 further includes a light detection device 11 that is supported by the bracket 9 in a fixed state on the machine frame 3. The light detection device 11 has a lower end portion inserted into the light lead-out portion 8 of the rotator 4 and supported by the machine frame 3, and a light condensing provided at the lower end inside the frame 12. The lens 13, the optical filter 14 disposed on the downstream side of the condenser lens 13 in the light traveling direction (in the case of FIG. 1, the upper side of the condenser lens 13), and the light transmission side of the optical filter 14 are provided. The first phototube 16a and the second phototube 16b provided on the light reflection side of the optical filter 14 are provided.
[0041]
The lower end portion of the light detection device 11 is inserted into the light lead-out portion 8 of the rotator 4, but a gap is formed between them, and the light detection device 11 remains stationary even when the rotator 4 rotates. To maintain. The optical filter 14 can be composed of a general transparent member, such as glass, and functionally transmits about 90% of the incident light and guides it to the first photoelectric tube 16a, and the remaining part of the incident light. About 10% of the light is reflected and led to the second photoelectric tube 16b. The phototubes 16a and 16b are photoelectric conversion elements having a known structure, and output signals corresponding to the intensity of incident light to the output terminals.
[0042]
The X-ray image reading apparatus 1 further includes a laser generator 27 incorporating a laser light source F0. The laser generator 27 emits laser light when the power is turned on (ie, turned on), and stops emitting laser light when the power is turned off (ie, turned off). A prism 28 is provided at a position below the laser beam introducing portion 6 of the rotating body 4. The laser light emitted from the laser generator 27 is reflected by the prism 28 and taken into the laser light introducing unit 6.
[0043]
A rotating disk 29 for generating pulses is provided at an appropriate position on the outer peripheral surface of the laser beam introducing section 6. As shown in FIG. 2B, the rotating disk 29 is formed in a substantially disk shape having a large diameter part 31a and a small diameter part 31b. Further, the first slit 32a is formed in the approximate center of the large diameter portion 31a, while the second slit 32b is formed in the approximate center of the small diameter portion 31b. As shown in FIG. 2A, the first slit 32a is provided at a position corresponding to the first read head H1, and the second slit 32b is provided at a position corresponding to the second read head H2.
[0044]
Further, in FIG. 1, a photo sensor 36 including a light emitting element 33 and a light receiving element 34 is provided at an appropriate place around the turntable 29. This photosensor 36 is the first because of the difference in diameter between the large-diameter portion 31a and the small-diameter portion 31b of the rotating disk 29 when the rotating body 4 rotates, that is, when the first reading head H1 and the second reading head H2 rotate. The difference between the first slit 32a and the second slit 32b is recognized, and a signal corresponding to each is output.
[0045]
Specifically, the index signal and the EVEN signal in the timing chart shown in FIG. 5 are generated. Here, the index signal is a pulse signal generated every half rotation (ie, 180 ° rotation) of the first read head H1 and the second read head H2. In addition, the EVEN signal is generated at the second rotation, the fourth rotation, the sixth rotation, ..., even rotations when the rotation of the rotating body 4 is viewed every half rotation (ie, 180 ° rotation). Is a pulse signal. In the present embodiment, the EVEN signal is a pulse signal generated when the first read head H1 scans the X-ray image holding body 17.
[0046]
In the present embodiment, the index signal and the EVEN signal function as reference pulses generated with reference to the positions of the read heads H1 and H2. The photosensor 36 functions as a means for generating the reference pulse.
[0047]
In FIG. 1, a main scanning rotation driving device 37 is connected to the rotating body 4 including the first reading head H1 and the second reading head H2. The main scanning rotation driving device 37 rotates the read heads H1 and H2 about the axis X0 to move the X-ray image holding body 17 in the lateral direction (that is, a direction forming a plane orthogonal to the axis X0 in FIG. 1). This is a device for scanning, that is, main scanning.
[0048]
The main scanning rotation drive device 37 can be configured by a drive system having an arbitrary structure. For example, a motor capable of controlling the rotation speed, such as a pulse motor or a servo motor, is used as a drive source, and the rotation output thereof is a belt, a gear, or the like. A structure in which the rotating body 4 is rotated by being transmitted to the rotating body 4 through the power transmission system can be adopted.
[0049]
A sub-scanning linear drive device 38 is connected to the machine frame 3 that supports the entire X-ray image reading device 1. The sub-scanning linear drive device 38 scans the X-ray image holding body 17 in the vertical direction (that is, the direction parallel to the axis X0 in FIG. 1) by moving the read heads H1 and H2 linearly in the direction parallel to the axis X0. That is, it is a device for performing sub-scanning.
[0050]
The sub-scanning linear drive device 38 can be configured by a drive system having an arbitrary structure. For example, a motor capable of controlling the rotation speed, such as a pulse motor or a servo motor, is used as a drive source to convert rotational power into straight power. It is possible to employ a structure that obtains straight power using a power conversion means, for example, a feed screw mechanism using a screw shaft. Moreover, it can also be comprised by the linear motor driven by a pulse.
[0051]
In this embodiment, in FIG. 1, by the laser generator 27, the prism 28, the beam stopper 18, and the first read head H1, and further by the laser generator 27, the prism 28, the beam stopper 18, and the second read head H2. In each case, an emission optical system is configured. The first reading head H1, the dichroic mirror 26a, and the light detection device 11, and the second reading head H2, the dichroic mirror 26b, and the light detection device 11, respectively, constitute a light receiving optical system.
[0052]
FIG. 4 shows an embodiment of a control system for controlling the movement of the X-ray image reading apparatus 1 of FIG. This control system is configured using a computer system having a CPU (Central Processing Unit) 41, a ROM (Read Only Memory) 42, a RAM (Random Access Memory) 43, an information storage medium 44, and a bus 46 connecting them. .
[0053]
In order to confirm the position of the read head, the output terminal of the photo sensor 36 attached to the turntable 29 of FIG. 1 is connected to the bus 46, the RESET terminal of the pulse generation circuit 47 is connected, and the intensity calculation circuit 48 The output terminal is connected, the ON / OFF signal input terminal of the laser generator 27 of FIG. 1 is connected, the control signal input terminal of the main scanning rotation driving device 37 of FIG. 1 is connected, and the sub-scanning straight travel of FIG. A control signal input terminal of the driving device 38 is connected. Further, an output device such as a printer 53 and a display 54 and an operation input device 56 such as a keyboard and a mouse type input device are connected to the bus 46.
[0054]
In this embodiment, the pulse generation circuit 47 functions as sampling pulse generation means for generating a sampling pulse based on the reference pulse. The intensity calculation circuit 48 functions as sampling means for sampling the data collected by the read head according to the sampling pulse.
[0055]
The pulse generation circuit 47 includes an oscillator 49 that can generate a stable pulse signal, a frequency divider 51 that divides the output pulse of the oscillator 49 into, for example, 1/16, and an output pulse of the frequency divider 51. And a logic circuit 52 that generates a pulse signal suitable for the control system according to the present embodiment. The oscillator 49 is a pulse signal that is significantly more stable than an output pulse signal when a commercially available encoder is attached to the rotating body 4 shown in FIG. 1 and a pulse signal is output from the encoder according to the rotation of the rotating body 4. For example, a crystal oscillator, a CR oscillator, or the like can be used.
[0056]
The oscillator 49 outputs, for example, a 5 MHz pulse signal, and the frequency dividing circuit 51 divides the 5 MHz pulse signal to generate, for example, a 312.5 KHz pulse signal. The frequency dividing circuit 51 outputs a pulse signal based on the time when the RESET signal is input to the RESET terminal. The logic circuit 52 generates the ENC (encode) -Z phase and ENC-A phase pulse signals shown in FIG. 5 based on the output pulses of the frequency divider circuit 51, and outputs them to the intensity calculation circuit 48.
[0057]
The ENC-A phase pulse input to the intensity calculation circuit 48 functions as a sampling pulse for determining a sampling period of light intensity data performed by the intensity calculation circuit 48.
[0058]
The ENC-Z phase pulse is obtained when a reset signal is input to the RESET terminal of the frequency dividing circuit 51, and thereafter, a 312.5 KHz pulse signal output from the frequency dividing circuit 51 is counted by a predetermined number, for example, 122 pulses. Are generated pulses. In this embodiment, in FIG. 5, the generation time tz of the ENC-Z phase pulse is set to tz = 122 pulses = 400 μS. This 400 μS is set as a sufficient time for the laser output to stabilize after rising according to the ON signal when the laser generator 27 is intermittently turned ON / OFF in the single head mode described later.
[0059]
The ENC-A phase pulse is a pulse that is output at the same frequency as 312.5 KHz of the frequency dividing circuit 51 from when the ENC-Z phase pulse is output to when the RESET signal is input to the frequency dividing circuit 51. It is. In the present embodiment, when an index signal or EVEN signal output from the photosensor 36 is output, a RESET signal is sent to the frequency dividing circuit 51, and an ENC-A phase pulse corresponding to the index signal or EVEN signal is sent. The output state of the ENC-Z phase pulse is as shown in FIG. In this embodiment, it is set so that 3000 pulses of 312.5 KHz are output as ENC-A phase pulses. The 3000 pulses correspond to a scanning area for one line of main scanning by the first reading head H1 and the second reading head H2.
[0060]
In FIG. 4, the intensity calculation circuit 48 counts the output pulses from the first phototube 16a or the second phototube 16b shown in FIG. 1 to thereby obtain the intensity of light emitted from the X-ray image holder 17 in FIG. Therefore, the energy intensity of the energy latent image formed on the X-ray image holding member 17, and hence the intensity of the X-ray contributing to the formation of the energy latent image is obtained by calculation.
[0061]
In the present embodiment, in FIG. 1, 90% of the light reaching the optical filter 14 is taken into the first phototube 16a, and the remaining 10% is taken into the second phototube 16b. When the amount of light taken into each phototube 16a and 16b is not excessive, processing is performed based on a signal photoelectrically converted by the first phototube 16a into which 90% of the light is taken.
[0062]
On the other hand, when the amount of light taken into each phototube 16a and 16b is excessive, processing is performed based on the signal photoelectrically converted by the second phototube 16b into which 10% of the light is taken. This is because if the amount of light is excessive, the output of the first phototube 16a becomes too large, and the circuit associated with the first phototube 16a may not operate normally.
[0063]
In FIG. 4, the intensity calculation circuit 48 samples the output signal of the phototube 16 a or 16 b for each one of the 3000 pulses sent from the logic circuit 52. That is, the output of the phototube 16a or 16b during one pulse period is read and output. This is a 1-pixel reading. This one-pixel reading is stored in a predetermined storage location in the RAM 43 of FIG.
[0064]
It should be noted that an AD conversion circuit is provided inside the intensity calculation circuit 48, and the output of the phototube 16a or 16b is sampled a plurality of times, for example, eight times within one pulse period, and each AD converted, further integrated and calculated. The result can be determined as a 1-pixel reading.
[0065]
In FIG. 4, an information storage medium 44 is a storage medium that can be used by a computer, and is an element for storing information such as programs and data. Its function is CD (Compact Disc), DVD (Digital Video). It can be realized by an optical disk such as Disc), a magneto-optical disk such as MO (Magnet Optical), a magnetic disk, a hard disk, a magnetic tape, a semiconductor memory such as a ROM, or the like. In a normal case, part or all of the information stored in the information storage medium 44 is transferred to the RAM 43 when the system is powered on.
[0066]
The ROM 42 stores, for example, a system program (that is, initialization information of the system main body). The RAM 43 is used as a work area for the CPU 41, temporarily stores information from the input / output device such as the contents of the information storage medium 44 and the ROM 42, the calculation results of the CPU 41, the intensity calculation circuit 48, and the like. .
[0067]
The CPU 41 controls operations of various input / output devices connected to the bus 46 according to programs stored in the information storage medium 44 and information input from the operation input device 56, and outputs signals from the intensity calculation circuit 48. The calculation for adding correction is performed, and various other data processing is performed. When the system shown in FIG. 4 is used as one user constituting a network, a network driver and a communication unit are connected to the bus 46, and are connected to a host and other network users via the network driver.
[0068]
The program used in this embodiment has a routine for causing the CPU 41 to execute the double head mode and a routine for causing the CPU 41 to execute the single head mode. The double head mode is a mode in which processing is performed using both the first read head H1 and the second read head H2 of FIG. 1, and the single head mode is the mode of the first read head H1 or the second read head H2. In this mode, processing is performed using any one of them. Hereinafter, each mode will be described individually.
[0069]
When the reading process according to the present invention is performed, a process for holding the energy latent image on the X-ray image holder 17 of FIGS. 1 and 2, for example, an X-ray exposure process is performed prior to the reading process. Is called. Various exposure processes are conceivable. For example, an X-ray measurement system as shown in FIG. 11 can be considered.
[0070]
In this X-ray measurement system, a sample S to be measured for its internal crystal structure and the like is supported by a gonio head 61, and X-rays emanating from the X-ray source F1 are directed to the sample S by a pinhole collimator 62. When the sample S is irradiated with X-rays in this way, diffracted X-rays, scattered X-rays and the like are generated from the sample S corresponding to the crystal structure of the sample S. These X-rays reach the stimulable phosphor surface of the X-ray image holding body 17, that is, the X-ray receiving surface while being regulated by the divergence regulating slit 63 and expose this surface.
[0071]
As a result of this X-ray exposure, the light-receiving surface of the X-ray image holder 17, that is, the stimulable phosphor surface, has coordinate positions corresponding to the diffraction angle of the diffracted X-rays, in other words, coordinates corresponding to the internal crystal structure of the sample S, etc. An energy latent image is formed at the position. For example, if the sample S is a powder sample, the Debye ring 64 is accumulated in the form of an energy latent image. With respect to the X-ray image holding body 17 which has thus held the energy latent image, the X-ray image reading apparatus 1 shown in FIG. 1 performs a latent image reading process under the double head mode or the single head mode.
[0072]
(Double head mode)
For example, the measurement accuracy is not high with respect to the X-ray image holding body 17 that has held the energy latent image at the diffraction angle position corresponding to the crystal structure of the sample S, that is, the coordinate position by the measurement using the measurement system shown in FIG. However, if it is desired to obtain the measurement result quickly, the operator selects to perform the measurement in the double head mode by the X-ray image reading apparatus 1 in FIG.
[0073]
Specifically, the operator instructs the CPU 41 to measure in the double head mode through the operation input device 56 in FIG. When this double head mode is selected and an instruction to start reading is given by the operator at timing T1 in the timing chart of FIG. 5, the CPU 41 sets the operation mode of the computer to the double head mode as Md.
[0074]
Then, the CPU 41 operates the main scanning rotation driving device 37 in FIG. 1 in response to the reading start at the timing T1 to start the rotation of the rotating body 4, and moves the first reading head H1 and the second reading head H2 to the axis X0. Rotate around. The rotation speed at this time is determined in advance to a predetermined speed, and the CPU 41 controls the operation of the main scanning rotation drive device 37 so that the rotation speed is maintained at a constant speed.
[0075]
When the first read head H1 and the second read head H2 rotate in this way, the index signal and the EVEN signal as shown in FIG. 5 are output from the photo sensor 36 shown in FIG. The index signal is a signal that is output every half rotation of the first read head H1 and the second read head H2 in the direction of arrow F in FIG. 2, that is, every 180 ° rotation angle. The EVEN signal is a signal output every rotation of the first read head H1 in the direction of arrow F, that is, every 360 ° rotation angle.
[0076]
Thereafter, in FIG. 5, when the timing T2 arrives, a light emission command is sent to the laser generator 27 of FIG. 1 to start laser light emission, and further, output of the Z-axis motor drive pulse is started and the sub-sequence of FIG. When the scanning linear drive device 38 starts to operate, the entire X-ray image reading device 1 and thus both the first reading head H1 and the second reading head H2 are parallel to the axis X0 as indicated by the arrow G. Start straight movement. At this time, the linear movement speeds of the first read head H1 and the second read head H2 are controlled to a constant speed V determined by the pulse width of the Z-axis motor drive pulse.
[0077]
As described above, when the first reading head H1 and the second reading head H2 perform main scanning rotation as indicated by an arrow F in FIG. As shown, the X-ray image holding body 17 is scanned in a spiral shape as indicated by the symbol P by the first reading head H1 and the second reading head H2 that alternately and repeatedly arrive at the X-ray image holding body 17. The
[0078]
The number of scans at this time, that is, the number of scan lines, is set to be 3000 lines, for example. In the case of the double head mode considered now, a total of two scanning lines are formed by each of the first reading head H1 and the second reading head H2 by one rotation of the rotating body 4 in FIG. Therefore, in order to form 3000 scanning lines, the rotating body 4 may be rotated 1500 times.
[0079]
While the first read head H1 and the second read head H2 scan the X-ray image holding body 17 as described above, the laser light emitted from the laser generator 27 in FIG. And is distributed to the first read head H 1 and the second read head H 2 by the beam splitter 18.
[0080]
When either the first read head H1 or the second read head H2 scans the surface of the X-ray image holding member 17, the laser beam supplied to the read head passes through the read head and scans in FIG. The X-ray image carrier 17 is exposed along the line P. When an energy latent image is held in the exposed portion of the X-ray image holding body 17 exposed by the laser beam in this way, the energy is excited by the laser beam and emitted to the outside as the emitted beam. Light is received by the emitted first read head H1 or second read head H2.
[0081]
The received light is reflected by the dichroic mirror 26a or 26b in the head portion 7 of the rotating body 4 and sent to the light detection device 11, and is received by the first phototube 16a and the second phototube 16b, and the outputs of these phototubes. A signal corresponding to the light is output to the terminal.
[0082]
While the X-ray image holding body 17 is irradiated with the laser beam as described above, in FIG. 5, it corresponds to the index signal output every half rotation of the first reading head H1 and the second reading head H2. In FIG. 4, a RESET signal is transmitted to the RESET terminal of the frequency dividing circuit 51 of the pulse generating circuit 47, whereby a single ENC-Z phase pulse and a continuous signal as shown in FIG. ENC-A phase pulse to be output.
[0083]
The ENC-Z phase pulse is a pulse signal generated after time tz from the index signal. Further, the ENC-A phase pulse is generated from the generation of the ENC-Z phase pulse to the generation of the next index signal, in other words, the first read head H1 or the second read head H2 is rotated half a turn (that is, 180 ° rotated). This is a pulse signal generated continuously during This ENC-A phase pulse is a pulse signal having a frequency of 312.5 KHz as shown in FIG. 6 according to the output pulse of the frequency dividing circuit 51 shown in FIG. 4, and is a half rotation of the read head, that is, one scan. 3000 pulses are generated in the line.
[0084]
The intensity calculation circuit 48 of FIG. 4 reads the output of the phototube 16 a or 16 b for each pulse of the ENC-A phase pulse output from the logic circuit 52, and the read value is stored in a predetermined area of the RAM 43. Thus, data for one pixel corresponding to one pulse of the ENC-A phase pulse is sampled. In the present embodiment, as shown in FIG. 7, the width of one pixel corresponds to 0.1 mm. Here, since the ENC-A phase pulse is output as 3000 pulses per scan line, the intensity calculation circuit 48 samples data for 3000 pixels obtained by dividing one scan line into 3000.
[0085]
Looking at the sampling situation for each scanning line, the index signal in FIG. 5 becomes a reference pulse, which is supplied to the pulse generation circuit 47 as a RESET signal at the head of each row of one scanning line, and based on this reference pulse. The ENC-A phase pulse as a sampling pulse is output for one line, that is, 3000 pulses. As described above, since the reference pulse is applied for each scanning line, each scanning line is accurately synchronized with the rotation operation of the read heads H1 and H2.
[0086]
The ENC-A phase pulse as a sampling pulse is not generated by the encoder according to the rotation of the read heads H1 and H2, but is generated based on the crystal oscillator 49 having extremely stable oscillation characteristics. is there. Therefore, the ENC-A phase pulse functions as a very stable sampling pulse that is not affected by the rotation of the read heads H1 and H2.
[0087]
As described above, after 3000 pixels of data relating to one scanning line are sampled, when the next reading head H1 or H2 arrives at a position facing the X-ray image holder 17, the reading head H1 or H2 causes the sub-scanning direction. 3000 pixels of data for the next scan line is sampled. Thereafter, data sampling for each scanning line is repeated alternately by the first reading head H1 and the second reading head H2, and as a result, data for 3000 lines are sampled in the sub-scanning direction. .
[0088]
As described above, in FIG. 7, the light intensity data relating to the entire measurement area of the X-ray image holding body 17 is read, and the data is stored in a predetermined area of the RAM 43 as a data table corresponding to the coordinate values of the X-ray image holding body 17. Remembered. This data table is the result of reading the latent image accumulated in the X-ray image holding body 17 without any change. The CPU 41 displays the result as an image on the screen of the display 54 as necessary, or displays it as a printed image on a printing material such as paper by the printer 53.
[0089]
In the double head mode, as described above, the reading process is performed by alternately using the two read heads of the first read head H1 and the second read head H2. In this case, the read characteristic by the first read head H1 and the read characteristic by the second read head H2 do not necessarily match.
[0090]
For example, the output level of the phototube 16a or 16b when the same object is read using the first read head H1 and the output level of the phototube 16a or 16b when read using the second read head H2 are not necessarily the same. Not. In FIG. 2, the first reading head H1 and the second reading head H2 must be placed symmetrically with each other at an angular interval of strictly 180 °. It is conceivable that the angle deviates from 180 ° due to an accuracy error.
[0091]
Therefore, highly accurate read data can be obtained without any correction between the read data obtained using the first read head H1 and the read data obtained using the second read head H2. I can't. Therefore, in the present embodiment, the CPU 41 in FIG. 4 previously performs a reading process on the same object using the first reading head H1 and the second reading head, and the difference in reading characteristics between the two is the same. Is collected as data, and the data is stored in the RAM 43 as correction data.
[0092]
Then, after performing measurement using both the first read head H1 and the second read head H2 and collecting the read data, the read data is converted into software based on the correction data stored in advance. By performing the correction, a process for joining the read data obtained using the first read head H1 and the read data obtained using the second read head H2 is performed. Thereby, the reliability regarding the read data obtained using a different read head can be improved. That is, the CPU 41 functions as an inter-head intensity correcting unit for compensating for an intensity error between the reading heads and an inter-head positional deviation correcting unit for compensating for an angular positional deviation between the reading heads.
[0093]
(Single head mode)
For example, the measurement using the measurement system shown in FIG. 11 takes a long time with respect to the X-ray image holding body 17 that has held the energy latent image at the diffraction angle position corresponding to the crystal structure of the sample S, that is, the coordinate position. However, when it is desired to obtain a highly accurate measurement result, the operator selects to perform measurement in the single head mode by the X-ray image reading apparatus 1 of FIG.
[0094]
Specifically, the operator instructs the CPU 41 to measure in the single head mode through the operation input device 56 in FIG. When this single head mode is selected and an instruction to start reading is given by the operator at timing T1 in the timing chart of FIG. 5, the CPU 41 sets the operation mode of the computer to the single head mode as Ms.
[0095]
Then, the CPU 41 operates the main scanning rotation driving device 37 in FIG. 1 in response to the reading start at the timing T1 to start the rotation of the rotating body 4, and moves the first reading head H1 and the second reading head H2 to the axis X0. Rotate around. The rotational speed at this time is the same as in the double head mode.
[0096]
When the first read head H1 and the second read head H2 rotate as described above, the index signal and the EVEN signal as shown in FIG. 5 are output from the sensor 36 shown in FIG. 1 in the same manner as in the double head mode. The
[0097]
Thereafter, in FIG. 5, when the timing T2 arrives, a light emission command is sent to the laser generator 27 of FIG. 1 to start laser light emission, and further, output of the Z-axis motor drive pulse is started and the sub-sequence of FIG. When the scanning linear drive device 38 starts to operate, the entire X-ray image reading device 1 and thus both the first reading head H1 and the second reading head H2 are parallel to the axis X0 as indicated by the arrow G. Start straight movement. The linear movement speed of the first read head H1 and the second read head H2 at this time is constant in the case of the double head mode by reducing the pulse width of the Z-axis motor drive pulse to 1/2 that in the double head mode. It is controlled to 1/2 of the speed V.
[0098]
In the double head mode, as shown in the timing chart of FIG. 5, the signal to the laser generator 27 is kept ON and the laser beam is always generated during the reading process. On the other hand, in the single head mode, as shown in the timing chart of FIG. 5, the period from the generation of the EVEN signal to the generation of the next index signal, that is, the first read head H1 is the X-ray image carrier. Only while scanning 17, an ON signal is sent to the laser generator 27 to generate laser light. The laser beam is not generated while the second read head H2 scans the X-ray image holding member 17. As a result, as shown in FIG. 8, the X-ray image holding member 17 is irradiated with laser light and the reading process is performed only while the first reading head H1 scans the X-ray image holding member 17. Thus, the reading process is not performed while the second reading head H2 scans the X-ray image holding body 17.
[0099]
Note that the moving speed of the X-ray image reading apparatus 1 in the sub-scanning direction in the single head mode (that is, the arrow G direction in FIG. 1) is ½ of the moving speed in the double head mode. Since the rotation speed of the rotating body 4 in the main scanning direction is set to be the same between the single head mode and the double head mode, the inclination angle of one scanning line in the single head mode is 1 in the double head mode. It becomes 1/2 of the inclination angle θ of the scanning line (see FIG. 7).
[0100]
Further, since the moving speed in the sub-scanning direction in the single head mode is set to ½ of the sub-scanning moving speed in the double head mode, the reading time for reading the X-ray image holding body 17 of the same size is single. The head mode takes twice as much as the double head mode.
[0101]
Also in the single head mode, the required number of scans, that is, the number of scan lines, is set to the same number of lines as in the double head mode, for example, 3000 lines. In the case of the single head mode considered now, since one scanning line is formed by only the first reading head H1 by one rotation of the rotating body 4 in FIG. 1, in order to form 3000 scanning lines. Rotates the rotating body 4 by 3000 times, that is, twice the double head mode.
[0102]
While the first read head H1 scans the X-ray image holding body 17 as described above, the laser light emitted from the laser generator 27 in FIG. 1 passes through the first read head H1 and passes through the scan line P in FIG. The X-ray image carrier 17 is exposed along the line. When an energy latent image is held in the exposed portion of the X-ray image holding body 17 exposed by the laser beam in this way, the energy is excited by the laser beam and emitted to the outside as the emitted beam. Light is received by the emitted first read head H1.
[0103]
The received light is reflected by the dichroic mirror 26a in the head portion 7 of the rotating body 4 and sent to the light detection device 11, and is received by the first phototube 16a and the second phototube 16b, and is output to the output terminals of these phototubes. A signal corresponding to the light is output.
[0104]
While the X-ray image holding body 17 is irradiated with the laser beam as described above, in FIG. 5, a pulse is generated in FIG. 4 corresponding to the EVEN signal output for each rotation of the first read head H1. A RESET signal is transmitted to the RESET terminal of the frequency dividing circuit 51 of the circuit 47, whereby a single ENC-Z phase pulse and a continuous ENC-A phase pulse as shown in FIG. Is output corresponding to each EVEN signal.
[0105]
The ENC-Z phase pulse is a pulse signal generated after time tz from the EVEN signal. The ENC-A phase pulse continues from the generation of the ENC-Z phase pulse to the generation of the next index signal, in other words, while the first read head H1 makes a half rotation (ie, 180 ° rotation). This is a pulse signal generated. This ENC-A phase pulse is a pulse signal having a frequency of 312.5 KHz as shown in FIG. 6 according to the output pulse of the frequency dividing circuit 51 shown in FIG. 4, and is a half rotation of the first read head H1, ie, 1 3000 pulses are generated in one scanning line.
[0106]
The intensity calculation circuit 48 of FIG. 4 reads the output of the phototube 16a or 16b for each pulse of the ENC-A phase pulse output from the logic circuit 52 in the same manner as in the double head mode. Is stored in a predetermined area. Thus, data for one pixel corresponding to one pulse of the ENC-A phase pulse is sampled. Here, since the ENC-A phase pulse is output as 3000 pulses per scan line, the intensity calculation circuit 48 samples data for 3000 pixels obtained by dividing one scan line into 3000.
[0107]
Looking at the sampling situation for each scanning line, the EVEN signal of FIG. 5 becomes a reference pulse and is supplied to the pulse generation circuit 47 as a RESET signal at the head of each row of one scanning line, and based on this reference pulse. The ENC-A phase pulse as a sampling pulse is output for one line, that is, 3000 pulses. Thus, since the reference pulse is given for each scanning line, each scanning line is accurately synchronized with the rotation operation of the first reading head H1.
[0108]
Further, the ENC-A phase pulse as the sampling pulse is not generated by the encoder according to the rotation of the first read head H1, but is generated based on the crystal oscillator 49 having extremely stable oscillation characteristics. is there. Therefore, the ENC-A phase pulse functions as a very stable sampling pulse that is not affected by the rotation of the first read head H1.
[0109]
When the second read head H2 arrives at the position facing the X-ray image holder 17 after sampling 3000 pixels of data for one scanning line by the first read head H1 as described above, the timing shown in FIG. As shown in the chart, ENC-Z phase pulse and ENC-A phase pulse are not output. At this time, the laser signal is also OFF, and the laser beam is not irradiated from the second read head H2. Therefore, no data is collected for the second read head H2.
[0110]
Thereafter, data of 3000 pixels over one scanning line is repeatedly sampled for each rotation of the first reading head H1, and as a result, 3000 lines of data are sampled in the sub-scanning direction. As described above, in FIG. 8, the light intensity data relating to the entire measurement area of the X-ray image holding body 17 is read, and the data is stored in a predetermined area of the RAM 43 as a data table corresponding to the coordinate values of the X-ray image holding body 17. Remembered.
[0111]
According to the measurement in the single head mode described above, only the first read head H1 is measured, and no data is collected from the second read head H2. Therefore, a situation in which a measurement error occurs due to a difference between the read characteristic when the first read head H1 is used and the read characteristic when the second read head H2 is used does not occur. Very accurate measurement can be performed.
[0112]
In the single head mode, as shown in FIG. 5, ON / OFF of the laser generator 27 is repeated every time the EVEN signal and the index signal are generated. At this time, even if the ON signal is sent to the laser generator 27 and the operation of the laser generator 27 is started, the laser beam with the rated intensity is not generated immediately, and the output of the laser beam is stabilized to the rated magnitude. It takes a little time. As shown in FIG. 5, when the EVEN signal is generated, the ENC-A phase pulse is not immediately output, but a delay time of tz, for example, 400 μS for 122 pulses is provided. This is to secure time until the rated size is stabilized.
[0113]
As described above, according to the X-ray image reading apparatus of the present embodiment, the ENC-A phase pulse, which is a sampling pulse, is read head H1, in both the double head mode and the single head mode. It is not generated from the encoder provided on the rotation axis of H2, but is obtained from the oscillator 49 which is an independent pulse generation source not affected by the rotation of the read heads H1 and H2, so that a stable sampling pulse is always obtained. Therefore, highly reliable read data can be obtained.
[0114]
The timing T2, which is a reference for generating the sampling pulse, is provided by a reference pulse generated with reference to the position of the read heads H1 and H2, that is, an index signal or an EVEN signal, so that the data sampling timing is determined by the read head H1. , H2, that is, there is no fear of deviating from the scanning timing of the X-ray image holding body 17.
[0115]
(Other embodiments)
The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications can be made within the scope of the invention described in the claims.
[0116]
For example, in the embodiment shown in FIG. 1, a single head mode is realized by not using the second read head H2 of the two read heads H1 and H2, and therefore, the second read that is not used. When the head H2 scans the X-ray image holding member 17, the generation of the laser beam from the laser generator 27 is stopped.
[0117]
However, the measures for not using the second read head H2 are not limited to such interruption of the laser light. For example, as shown in FIG. 9, a beam splitter 18 and a second read head are used. This can also be realized by providing a beam stopper or shutter 59 on the optical path to H2 and preventing the laser light from traveling to the second read head H2 by this beam stopper or shutter 59.
[0118]
In the above embodiment, the present invention is applied to a double-head X-ray image reading apparatus having a structure using two reading heads. However, the present invention uses three or more reading heads. The present invention can also be applied to a multi-head X-ray image reading apparatus having a structure.
[0119]
【The invention's effect】
As is apparent from the above description, according to the X-ray image reading apparatus of the present invention, the sampling pulse is not generated from the encoder provided on the rotation shaft of the read head, but is rotated by the rotation of the read head. Therefore, a stable sampling pulse can always be obtained, and therefore highly reliable read data can be obtained.
[0120]
In addition, since the timing used as the reference for generating the sampling pulse is provided by the reference pulse generated with reference to the position of the read head, the data sampling timing is determined by the rotation of the read head, that is, the scanning of the X-ray image carrier. There is no worry of getting out of timing.
[Brief description of the drawings]
FIG. 1 is a side cross-sectional view showing an embodiment of an X-ray image reading apparatus according to the present invention.
2A is a plan cross-sectional view according to the line II-II in FIG. 1, and FIG. 2B is a plan cross-sectional view according to the line III-III in FIG.
FIG. 3 is a view showing a beam splitter used in the apparatus of FIG. 1;
FIG. 4 is a block diagram showing an embodiment of an electric control system used in the X-ray image reading apparatus according to the present invention.
FIG. 5 is a timing chart of control executed by the electric control system of FIG.
6 is a timing chart showing the main part of FIG.
FIG. 7 is a diagram schematically showing a reading scan state in a double head mode.
FIG. 8 is a diagram schematically showing a reading scan state in a single head mode.
FIG. 9 is a side sectional view showing another embodiment of the X-ray image reading apparatus according to the present invention.
FIG. 10 is a perspective view showing an example of a conventional X-ray image reading apparatus.
FIG. 11 is a perspective view showing an example of an X-ray measurement apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 X-ray image reader 4 Rotating body 6 Laser beam introducing | transducing part 7 Head part 8 Light derivation | leading-out part 11 Photodetector 14 Optical filter 16a, 16b Phototube 17 X-ray image holding body 18 Beam splitter 26a, 26b Dichroic mirror 27 Laser generator 29 Turntable (means for generating reference pulse)
36 Photosensor (means for generating reference pulse)
47 Pulse generation circuit (sampling pulse generation means)
48 Strength calculation circuit (sampling means)
59 Beam stopper or shutter H1 First read head H2 Second read head

Claims (10)

A read head for collecting data from the X-ray image carrier by irradiating the X-ray image carrier with stimulating excitation light ;
A scanning drive means for moving the said reading head for secondary scanning perpendicular main scanning and that of the X-ray image holding member,
Means for generating a reference pulse relative to the position of the read head;
Sampling pulse generating means for generating a sampling pulse based on the reference pulse;
Sampling means for sampling data collected by the read head according to the sampling pulse;
Have
The scanning drive means linearly moves the read head in a direction perpendicular to the rotation surface of the read head by the rotary drive means for sub-scanning and rotational drive means for rotationally driving the read head for main scanning. Straight drive means for moving,
The means for generating the reference pulse generates a reference pulse when the rotating read head reaches a predetermined position,
The stimulated excitation light emits according to the reference pulse,
The sampling pulse generation means starts generation of the sampling pulse after a lapse of time after generation of the reference pulse,
The X-ray image reading apparatus according to claim 1, wherein the sampling pulse generating means generates a sampling pulse independently from the scanning driving means. In claim 1,
A plurality of the read heads are provided,
The X-ray image reading apparatus, wherein the scanning drive unit moves the plurality of reading heads so that the plurality of reading heads scan the X-ray image holding body at different timings. In claim 2,
It said read head is, X-rays image reading apparatus characterized by being arranged in two is symmetrical positions at angular intervals of 180 ° from each other. In claim 1 any one of claims 3,
Means for generating a reference pulse with respect to the position of the read head;
A rotating disk attached to a rotating shaft of the rotationally driven read head;
An X-ray image reading apparatus comprising: a photosensor that outputs a pulse signal in accordance with the rotation of the turntable. In claims 1 one claim 4 Neu Zureka, means for generating a reference pulse position of the read head as a reference, characterized by generating the reference pulse at the beginning of each line of the plurality of scan lines X-ray image reading apparatus according to. In one claim 5 gall Zureka claims 1,
The sampling pulse generating means includes
Original oscillation means for oscillating a frequency higher than the frequency of the sampling pulse;
An X-ray image reading apparatus comprising: a frequency dividing circuit that divides the output pulse of the original oscillation means. In claim 6,
The X-ray image reading apparatus characterized in that the original oscillation means outputs an oscillation having a frequency 10 times or more the frequency of the sampling pulse.   8. The X-ray image reading apparatus according to claim 6, wherein the original oscillation means includes a crystal oscillation source. In the claims 6 to one claim 8 Neu Zureka, said oscillation means to oscillate the 5 MHz, X-ray image reading apparatus, wherein the sampling pulse is 312.5 KHz. In Zureka one claims 9 Neu claim 1,
The X-ray image holding body has an X-ray holding surface formed of a stimulable phosphor, and an emission optical system that supplies stimulated excitation light to the one or more read heads;
A light receiving optical system that receives light emitted from the X-ray image holding body through the one or more reading heads and outputs an electrical signal corresponding to the light reception;
An X-ray image reading apparatus, wherein the output signal of the light receiving optical system is sampled by the sampling means.

Images