JPH01181275A - Picture recording medium carrier device - Google Patents

Abstract

PURPOSE:To prevent the resonance with a case at the carrying of a picture recording medium by generating a drive pulse synchronously with the main scanning by a deflection means, supplying the drive pulse to a pulse motor and driving the carriage of the picture recording medium in the subscanning direction CONSTITUTION:The start of the main scanning of a light collector 11 is detected by a sensor 21, and he sensor 21 generates a SYNC signal. The pulse given to a pulse motor 34 is a pulse synchronously with the SYNC signal, the sampling pitch is 100mum and the interval of the SYNC signal is 5mS and the film carrying amount per pulse is 25mum, then the pulse interval is 1.25mS and the frequency is 800Hz. In the provision of the consecutive pulse train to the pulse motor, since no resonance between the pulse motor 34 and the device case is caused, the measuring accuracy is high and the reproduced picture with excellent adaptation of observation and image reading is obtained.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a method for writing image information on an image recording medium or reading out image information from the image recording medium. The present invention relates to an image recording medium transport device used for transporting an image recording medium.

(Prior Art) In the past, images stored on an image recording medium such as film, especially images from X-ray film, were placed on a Scherkasten or the like and diagnosed directly by visual inspection, but in recent years, images stored on film have been After scanning with a narrowly focused laser beam and converting it into an electrical signal, it is subjected to various image processing such as spatial frequency processing and gradation processing to emphasize information useful for medical diagnosis, and then played back for diagnosis. It has become.

With this method, more diagnostic information can be obtained from a single X-ray R image, improving diagnostic performance. Furthermore, it is also expected to improve the efficiency of storing and retrieving X-ray image information.

The system configuration diagram shown in FIG. 4 is explained as follows. An image stored on a film 1, which is an image recording medium, is read by a film image reading device 2 by scanning the film 1 with a laser beam. This read information is sent to the data processing device 3 after being converted into a digital signal. The data processing device 3 performs data processing such as frequency emphasis and edge emphasis on the sent image information.

This provides images with excellent diagnostic suitability. The display device 4 visualizes the data-processed image.

FIGS. 5(a) and 5(b) show a conventional film image reading device 2.
It is a conceptual diagram. 5 is a laser oscillator that generates a laser beam, and 6 is a beam expander that expands the aperture of the incident laser beam to an arbitrary size to reduce the spread angle of the laser beam.

For example, the beam diameter of the laser beam can be set to 5 by the beam expander 6.
When magnified twice, the spread angle of the laser beam decreases to 115.

Reference numeral 7 designates a high-speed angle change mirror that reflects the incident laser light in the main scanning direction at a constant angular velocity, and a galvanometer or polygon is generally used.

Reference numeral 8 denotes an fθ lens, which serves to focus the laser beam on the same plane by keeping the linear velocity constant when the laser beam is incident at a constant angular velocity.

Reference numerals 9a and 9b are film feed rollers, which hold the film 10 on which image information is stored and run the film 10 at a predetermined speed in a direction perpendicular to the main scanning direction (sub-scanning direction).

The entire surface of the film 10 is scanned by the laser beam by the sub-scanning by the film feed rollers ga and gb and the main scanning by the high-speed angle change mirror 7.

11 is a laser beam that has passed through the film 10 and entered,
It is a condenser that guides the light to the detector 12 that converts it into an electric signal, and includes an optical system such as a bundled optical fiber and a lens.
A transparent acrylic resin or the like whose output end is processed so as to efficiently transmit incident light to the detector 12 is used.

An electronic circuit is connected after the detector 12, and in this electronic circuit, the light that has passed through the film 10 is correlated with the position information of each pixel and converted into a digital signal in time series.

The principle of film density measurement is as follows.

The reference light amount incident on the detector 12 is IO, the light amount incident on the detector 12 when there is no film and when there is a film is 1 and 12, respectively, and the S degree at that time is D1, respectively.
and Dl, the relationship between concentration and light is Dl = -1
001t/Io, D2=-1ONz/Io.

At this time, if we calculate the density D3 which is the difference between the fa degree D2 when there is a film and the density D1 when there is no film, we get D
3=02-Dl=-109Iz/It, which indicates the density of the film.

That is, if the density D1 when there is no film is measured and memorized in advance, and the density D2 when the film is placed is measured and the difference from the above-mentioned memorized density is calculated, that value will be calculated based on the film density. This indicates 81 degrees D3.

FIG. 6 shows the electronic circuit of the film image reading device 2. As shown in FIG. As described above, since the concentration has a log dimension, the signal converted into an electrical signal by the detector 12 is first converted into a log signal by the log amplifier 13.

The sample/hold circuit 14 holds the output signal of the log amplifier 13 in the previous stage in synchronization with a clock signal input from a controller (not shown) that manages the entire electronic circuit. converts the signal held by the sample/hold circuit 14 into a digital quantity.

The above controller divides continuous image information into pixels by generating a clock signal corresponding to the main scanning speed. The switch 16 sends the signal output from the A/D converter 15 to the calibration buffer 17 or line buffer 18 according to a signal instructed by the controller. That is, the switch 16 is configured so that the density information when the film 10 is not placed in FIG. 5 is sent to the calibration buffer 117, and the density information when the film 10 is placed is sent to the line buffer 18. Operate.

Calibration buffer 17 and line buffer 718
is a circuit that functions to store digital signals of the number of pixels for one line, and advances the storage address by a clock signal input from a controller (not shown) to associate pixel position information with stored information.

19 is a difference calculation circuit, which is connected to the line buffer 18 at the previous stage.
It has a function of calculating the difference between the film density information stored in the calibration buffer 17 and the 'a degree information stored in the calibration buffer 17 for each corresponding pixel based on a signal input from a controller (not shown). This difference becomes the density of the film.

Reference numeral 20 denotes an interface, which sends the output signal of the difference calculation circuit 19 to the data processing device 3.

In the above configuration, first, the density of one line when there is no film is measured, and this is stored in the calibration buffer 17. Next, the film feed roller 9a
, 9b move the film 10 in the sub-scanning direction to the high-speed angle change mirror 7.
The density of one line is measured with the film present, and the measured value is stored in the line buffer 18.

Thereafter, by the action of a controller (not shown), the contents of the calibration buffer 17 and line buffer 118 are sent one after another to the difference calculation circuit 19, the difference, that is, the density of the film is calculated, and the calculation result is sent via the interface 20. The data is sent to the data processing device 3.

After one line of data is transferred to the data processing device 3, the film feed rollers 9a and 9b move the film 10 by a predetermined distance in the sub-scanning direction, and the next line is measured. Such operations are performed one after another, and the entire surface of the film 10 is measured.

(Problems to be Solved by the Invention) Conventional devices can convert image information into digital density information with high precision. However, in the scanning performed when reading images with this conventional device, the film on which the image is stored is scanned with a laser beam in the main scanning direction, while the film is moved at a constant speed in the sub-scanning direction. and
There was no special relationship between main scanning and backward scanning.

Since high precision is required to drive the film feed roller that moves the film in the sub-scanning direction,
Although not shown in (b), a pulse motor is used. If the processing precision of the film feed rollers 9a and 9b is improved, it is possible to easily create a configuration that allows the film to move with high precision, for example, by 25 μm per pulse input to the pulse motor. However, in the conventional device, there are cases where the drive pulses applied to the pulse motor are not a continuous pulse series, that is, the drive pulses are in a so-called "toothless" state. The disadvantage is that intermittent driving causes resonance with the casing of the device, and this resonance generates abnormal noise.

If the device resonates, it will also cause the film to be measured to vibrate, reducing measurement accuracy. Moreover, the abnormal noise gives operators and doctors a great sense of anxiety and distrust of the device.

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and it is an object of the present invention to provide an image recording medium transport device that prevents resonance with the casing during transport of the image recording medium.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides two-dimensional scanning with a laser beam on an image recording medium by main scanning by a deflection means that deflects the laser beam and sub-scanning perpendicular to the main scanning direction. An image recording medium that is included in a device that can write image information on or read image information from an image recording medium by scanning the image recording medium, and that performs the above-mentioned sub-scanning by transporting the image recording medium. A transport device comprising a drive pulse generating means that generates a drive pulse in synchronization with the main scanning, and a pulse motor that drives the image recording medium to be transported in the sub-scanning direction by supplying the drive pulse. It is.

(Function) In the present invention, driving pulses are generated in synchronization with the main scanning by the deflection means, and the driving pulses are supplied to the pulse motor to drive the movement of the image recording medium in the sub-scanning direction. As a result, the train of drive pulses does not become discontinuous as in the conventional case, and therefore resonance with the housing can be prevented.

(Example) Hereinafter, the present invention will be specifically explained with reference to Examples.

FIG. 1 shows an embodiment of the present invention, in which the present invention is applied to a film image reading device. In FIG. 1, parts having the same functions as those shown in FIG. 5(a) are given the same reference numerals, and detailed explanation thereof will be omitted.

In FIG. 1, reference numeral 20 denotes drive pulse generation means for generating drive pulses in synchronization with main scanning by the deflection means;
1 drives the transport of the film 10, which is an image recording medium, in the sub-scanning direction (direction perpendicular to the paper surface) by supplying the drive pulses generated by the drive pulse generation means 20, and is driven by the pulse motor 34. The force is roller 9a.

9b.

Here, as the above-mentioned deflection means, a high-speed angle change mirror (for example, polygon) 7 that deflects the laser beam is used.

Although not shown, a sensor is provided at a position capable of detecting the start of main scanning of the condenser 11, and this sensor generates a 5YNC (synchronization) signal. This 5YNC Shintan is taken into the drive pulse generation means 20.

FIG. 2 shows a detailed configuration of the drive pulse generating means 20. As shown in FIG. As shown in the figure, the drive pulse generating means 20 includes an oscillator 30. Frequency reduction circuit 31, microcomputer 32. It includes a pulse motor drive circuit 33. The oscillator 30 generates, for example, a train of 8HII2 pulses, and this train of 8 MHz pulses is sent to a frequency reduction circuit 31 disposed at a subsequent stage. This frequency reduction circuit 31 reduces the pulse train of 8 Hllz to the frequency specified by the microcomputer 32, and in this embodiment, a programmable frequency reduction circuit 31 is applied. For example, when the sampling pitch for image information reading is 100 μm, the frequency reduction circuit 31 reduces the 8 MHz pulse train to 800H2 (ie, 1/10000) under the control of the microcomputer 32.

In addition, the microcomputer 32 also includes a frequency reduction circuit 31.
In addition, it also has the function of managing the rotational speed of the high-speed angle change mirror 7 (polygon here) shown in FIG. 1 and the entire electronic circuit shown in FIG.

The pulse motor drive circuit 33 has the function of power amplifying the input pulse signal and supplying it to the pulse motor 34. The pulse motor 34 is connected to the film feed rollers ga and gb shown in FIG. 1 by gears or belts. Depending on the rotation angle and gear ratio of the pulse motor 34 and the outer diameters of the film feed rollers 9a and 9b, when one pulse enters the pulse motor 34, the film 10 is moved a certain distance (25 μm in this case).

Between the frequency reduction circuit 31 and the pulse motor drive circuit 33, there is a gate circuit (not shown) that is opened and closed under the control of the microcomputer 32, and the gate is opened only when the film is fed to allow the pulse signal to pass through. The rest are closed to prevent pulse signals from being transmitted to the subsequent stages.

The sampling pitch of the film to be measured is known to the microcomputer 32 before starting the measurement. For example, if the sampling pitch is 100μm, rotating polygon 7 at 1500rl)m will result in 5YNC (synchronization).
Since the signal interval is 5 mS, in order to give the pulse motor drive circuit 33 4 pulses in 5 mS, the q microcomputer 32 instructs the oscillator 30 to output a series of pulses of 1/10000, that is, 800H2. . If the sampling pitch is, for example, 150 μm, the microcomputer 32 divides the polygons into 200 or
Rotate at pm. In this case, the interval between the 5YNC signals is 3
．． 75 m5, and the pulse motor 34 has this 3°75
Since 6 pulses must be given during m5, the microcomputer 32 controls the frequency reduction circuit 31 so that the pulse interval is 0.625 m5, or 1600 tlz.
instruct.

Similarly, if the sampling pitch is 200 μm, the microcomputer 32 scans the polygons at 2500 rpm.
Therefore, it is necessary to give 8 pulses to the pulse motor 34 for 3 mS, and the pulse interval is 0.375 m.
5, and under the control of the microcomputer 32, the frequency reduction circuit 31 reduces the pulse train to 1/3000.

In this manner, the frequency reduction circuit 31 reduces the pulse train output by the oscillator 30 in accordance with the rotation speed of the polygon.

Next, the operation of the embodiment device configured as described above will be explained.

Figure 3 shows that the sampling pitch, which is the interval between each pixel, is 1
00 μm, and the operation timing is shown when an 8-sided polygon rotating at 1500 rpm is used as a high-speed angle change mirror.

The figure (A> shows the relationship between the main scanning by the laser beam and the light incident end face of the condenser 11, and the time during which one surface of the polygon 7 is scanned is 5 ms in this case. Vessel 1
The start of main scanning 1 is detected by a sensor 21, and this sensor 21 generates a 5YNC signal as shown in FIG.

FIG. 2C shows a clock signal given to the pulse motor 34 in a conventional device, and here it is set to 1 Hz. This clock signal and the 5YNC signal were not related to each other in conventional devices. In this case, it is assumed that the pulse motor 34 moves the film by, for example, 25 μm when one pulse is applied.

In the same figure (D> is the timing of the conventional drive pulse given to the pulse motor. Here, the sampling pitch is 100 μm, so the number of pulses given to the pulse motor is 4 pulses. Note that the microcomputer is After giving 4 driving pulses to the motor, 5YNC
When a signal is input, the measurement of the next line is controlled, and in this case, since the drive pulse is in a state where it can be treated as a tooth, resonance with the casing occurs, causing the above-mentioned problem.

(E) in the same figure shows a series of pulses applied to the pulse motor 34 in the device of this embodiment. In this case, the pulse is synchronized with the 5YNC signal, and the sampling pitch is 100.
Since the interval between the 5YNC signals is 5 mS and the film transport amount per pulse is 25 μm, the pulse interval is 1.25 m5 and the frequency is 800H2.

If a continuous pulse train is applied to the pulse motor as shown in FIG. You can (q) the image.

When the device of this embodiment is operated, the following occurs.

Since the operation of the electronic circuit is similar to that already described with reference to FIG. 6, it will not be discussed here.

When measuring at a sampling pitch of 100 μm, the microcomputer 32 rotates the polygon 7 at a rate of 1500 rl)m, so the interval between the 5YNC signals is 5 mS.
Four pulses must be sent to the pulse motor drive circuit 33 during this 5 mS period. Therefore, the microcomputer 32 operates the frequency reduction circuit 31 at 1/10000.

The sampling pitch is 150 μm each.

In the case of 200 μm, the microcomputer 32 sets the frequency reduction circuit 31 to 115000.1/3000, respectively.
Make it. In this case, the pulses transmitted to the pulse motor drive circuit 33 are continuous pulses as shown in FIG. 3(E).

If the load on the film feed rollers 9a, 9b is large and the frequency of the pulses transmitted to the pulse motor drive circuit 33 is high and exceeds the automatic activation of the pulse motor 34, for example, during main scanning two or three times. All you have to do is move it by the set sampling pitch. That is, for example, if the sampling pitch is 200 μm, the frequency of the pulse entering the pulse motor drive circuit 33 is 8 MHz / 3000 = 2.67 KHz, and this number is: ・Depending on the size of the load, the frequency of the pulse that enters the pulse motor drive circuit 33 is This goes beyond the self-starting of motors. in this case,
In order to move the film 200 μm during three main scans, the microcomputer 32 uses a frequency reduction circuit 3.
1 should be operated at 1/9000.

In this way, in the device of this embodiment, the pulse motor drive circuit 3 is
The drive pulse given to 3 is a continuous pulse synchronized with the 5YNC signal indicating the start of measurement, so that no resonance occurs between the pulse motor 34 and the housing. Therefore, no abnormal noise is generated, and the film 1 during measurement
Since the 0 does not oscillate, a read image with high measurement accuracy can be obtained, which greatly contributes to improving diagnostic performance.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above embodiment, and various modifications can be made.

In the above embodiment, the output of the oscillator 30, which has a constant oscillation frequency, is reduced by the frequency reduction circuit 31 and given to the pulse motor drive circuit 33. If an oscillator is used and the rotation of the polygon 7 is, for example, 1500 rpm, the oscillation frequency should be set to 80 rpm.
0Hz.

This oscillator may oscillate a pulse having a frequency corresponding to the rotational speed of the polygon 7, such as 1600H2 at 200Orpm. In this case, the frequency reduction circuit 31 described above becomes unnecessary.

Incidentally, in the above embodiment, the case where the present invention is applied to a film image reading device has been described, but the present invention can be applied to other devices besides this film image reading device.

For example, a laser beam modulated in light intensity by an image signal is two-dimensionally scanned onto a film, which is an image recording medium, by main scanning using a deflection means such as a polygon and sub-scanning perpendicular to the main scanning. Image recording devices that write image information, and radiation image reading devices that irradiate excitation light onto a phosphor sheet containing a stimulable phosphor and read radiation image information prerecorded on the phosphor sheet. The present invention can also be applied to.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to provide an image recording medium transport position that prevents resonance with the casing during transport of the image recording medium.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the present invention, FIG. 2 is a detailed configuration block diagram of the main part of FIG. 1, FIG. 3 is a timing diagram for explaining the operation of the device of this embodiment, and FIG. The figure is a system configuration block diagram of the Ryōkai processing device, FIGS. 5(a) and 5(b) are configuration explanatory diagrams of a conventional film image reading device, and FIG. 6 is a configuration block diagram of an electronic circuit in the film image reading device. be. 7... Polygon (deflection means), 10... Film (image recording medium), 20... Drive pulse generation means, 34... Pulse motor. Agent Patent Attorney Nori Ken Yudo Konfuji Takeshi Figure 1

Claims (1)

[Claims] The image recording medium is scanned two-dimensionally with a laser beam by main scanning by a deflection means that deflects the laser beam and sub-scanning perpendicular to the main scanning direction to write image information on the image recording medium or to write image information on the image recording medium. Generating drive pulses in synchronization with the main scanning in an image recording medium transport device that is included in a device that enables reading of image information from an image recording medium and performs the above sub-scanning by transporting the image recording medium. 1. An image recording medium transport device comprising: a drive pulse generating means for generating a driving pulse; and a pulse motor driving the movement of the image recording medium in a sub-scanning direction by supplying the drive pulse.