U.S. patent application number 17/108500 was filed with the patent office on 2021-06-03 for radiation imaging system, imaging control device, and storage medium.
The applicant listed for this patent is Konica Minolta, Inc.. Invention is credited to Mao EGUCHI, Keisuke KOEDA, Hiroaki NAKANO, Takeshi NUKANOBU, Atsushi TANEDA.
Application Number | 20210165113 17/108500 |
Document ID | / |
Family ID | 1000005262046 |
Filed Date | 2021-06-03 |
United States Patent
Application |
20210165113 |
Kind Code |
A1 |
NUKANOBU; Takeshi ; et
al. |
June 3, 2021 |
RADIATION IMAGING SYSTEM, IMAGING CONTROL DEVICE, AND STORAGE
MEDIUM
Abstract
A radiation imaging system including: a radiation generator that
includes a radiation source generating a radiation pulse by
receiving a tube current of a preset amount; a radiation detector
that includes a plurality of charge accumulators which accumulate
and release electric charges to be read out as signal values
according to received radiation and that generates a dynamic image
formed of a plurality of frames; and a hardware processor. The
hardware processor sets an amount of the tube current and a length
of an accumulation time for which the charge accumulators are
allowed to accumulate the electric charges, calculates such a
proper range of the tube current that start and end of generation
of one radiation pulse by the radiation generator are within one
accumulation time to perform an imaging with the accumulation time,
and regulates setting of a value out of the proper range.
Inventors: |
NUKANOBU; Takeshi; (Tokyo,
JP) ; KOEDA; Keisuke; (Tokyo, JP) ; EGUCHI;
Mao; (Tokyo, JP) ; TANEDA; Atsushi; (Tokyo,
JP) ; NAKANO; Hiroaki; (Sagamihara-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Konica Minolta, Inc. |
Tokyo |
|
JP |
|
|
Family ID: |
1000005262046 |
Appl. No.: |
17/108500 |
Filed: |
December 1, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01T 1/1635 20130101;
G01T 1/2978 20130101; G01T 1/175 20130101 |
International
Class: |
G01T 1/163 20060101
G01T001/163; G01T 1/175 20060101 G01T001/175; G01T 1/29 20060101
G01T001/29 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 3, 2019 |
JP |
2019-218444 |
Claims
1. A radiation imaging system comprising: a radiation generator
that includes a radiation source which generates a radiation pulse
by receiving supply of a tube current of a preset amount; a
radiation detector that includes a plurality of charge accumulators
which accumulate and release electric charges to be read out as
signal values according to received radiation and that generates a
dynamic image formed of a plurality of frames; and a hardware
processor that: sets an amount of the tube current and a length of
an accumulation time for which the charge accumulators are allowed
to accumulate the electric charges; calculates such a proper range
of the tube current that start and end of generation of one of the
radiation pulse by the radiation generator are within one of the
set accumulation time to perform an imaging with the set
accumulation time; and regulates setting of a value out of the
calculated proper range.
2. The radiation imaging system according to claim 1, wherein the
hardware processor sets, as the amount of the tube current, a value
of an option that is selected from among a displayed option by a
user or an arbitrary value that is input by the user, and the
hardware processor regulates the setting of the value out of the
calculated proper range.
3. The radiation imaging system according to claim 2, wherein the
hardware processor notifies that the value out of the calculated
proper range is selected or input in response to selection or
inputting of the value out of the calculated proper range.
4. The radiation imaging system according to claim 1, wherein the
hardware processor is able to set a frame rate, the hardware
processor determines whether or not a value of at least one of the
frame rate and the accumulation time set in the radiation generator
matches a value of the at least one of the frame rate and the
accumulation time set in the radiation detector, and the imaging is
enabled in response to determination by the hardware processor that
the value set in the radiation generator matches the value set in
the radiation detector.
5. The radiation imaging system according to claim 1, wherein the
radiation generator applies, to the radiation source, a tube
voltage that is set in advance to generate the tube current, and
the radiation source generates the radiation pulse for an
irradiation time that is set, the hardware processor is able to set
a value of at least one of the tube voltage and the irradiation
time, the hardware processor calculates a proper range of a value
of at least one of the tube voltage and the irradiation time
according to the set length of the accumulation time, and the
hardware processor regulates setting of the value of the at least
one of the tube voltage and the irradiation time out of the
calculated proper range.
6. The radiation imaging system according to claim 5, wherein, in
response to setting of a second value that is larger than a first
value as a parameter value of at least one of the tube current, the
tube voltage and the irradiation time, the hardware processor
lowers a parameter value that is not set to be the second value
among the tube current, the tube voltage and the irradiation time
such that a total dose in a single imaging of the dynamic image
among the imaging does not exceed a total dose in a single imaging
of the dynamic image among the imaging that is performed by setting
the first value.
7. The radiation imaging system according to claim 1, wherein the
hardware processor identifies the connected radiation generator,
and the hardware processor adjusts the proper range of a value to
be calculated according to the identified radiation generator.
8. An imaging control device that controls a radiation generator
and a radiation detector, the radiation generator including a
radiation source which generates a radiation pulse by receiving
supply of a tube current of a preset amount, the radiation detector
including a plurality of charge accumulators which accumulate and
release electric charges to be read out as signal values according
to received radiation and generating a dynamic image formed of a
plurality of frames, and the imaging control device comprising a
hardware processor that: sets an amount of the tube current;
calculates such a proper range of the tube current that start and
end of generation of one of the radiation pulse by the radiation
generator are within one of an accumulation time which is set in
advance to perform an imaging with the set accumulation time; and
regulates setting of a value out of the calculated proper
range.
9. The imaging control device according to claim 8, further
comprising a display that displays an option of a value which is
settable as the amount of the tube current, wherein the hardware
processor sets, as the amount of the tube current, a value of an
option that is selected from among the option displayed on the
display by a user or an arbitrary value that is input by the user,
and the hardware processor regulates the setting of the value out
of the calculated proper range.
10. The imaging control device according to claim 9, wherein the
hardware processor notifies that the value out of the calculated
proper range is selected or input in response to selection or
inputting of the value out of the calculated proper range.
11. The imaging control device according to claim 8, wherein the
hardware processor is able to set a frame rate in the radiation
generator and the radiation detector, the hardware processor
determines whether or not a value of at least one of the frame rate
and the accumulation time set in the radiation generator matches a
value of the at least one of the frame rate and the accumulation
time set in the radiation detector, and a permission to perform the
imaging is output to at least one of the radiation generator and
the radiation detector in response to determination by the hardware
processor that the value set in the radiation generator matches the
value set in the radiation detector.
12. The imaging control device according to claim 8, wherein the
hardware processor is able to set a value of at least one of a tube
voltage which is applied to the radiation source by the radiation
generator to generate the tube current and an irradiation time for
which the radiation source generates the radiation pulse, the
hardware processor calculates a proper range of a value of at least
one of the tube voltage and the irradiation time according to a
length of the set accumulation time, and the hardware processor
regulates setting of the value of the at least one of the tube
voltage and the irradiation time out of the calculated proper
range.
13. The imaging control device according to claim 11, wherein, in
response to setting of a second value that is larger than a first
value as a parameter value of at least one of the tube current, a
tube voltage and an irradiation time, the hardware processor lowers
a parameter value that is not set to be the second value among the
tube current, the tube voltage and the irradiation time such that a
total dose in a single imaging of the dynamic image among the
imaging does not exceed a total dose in a single imaging of the
dynamic image among the imaging that is performed by setting the
first value.
14. The imaging control device according to claim 8, wherein the
hardware processor identifies the connected radiation generator,
and the hardware processor adjusts the proper range of a value to
be calculated according to the identified radiation generator.
15. A non-transitory storage medium storing a computer readable
program for a computer in an imaging control device that controls a
radiation generator and a radiation detector, the radiation
generator including a radiation source which generates a radiation
pulse by receiving supply of a tube current of a preset amount, the
radiation detector including a plurality of charge accumulators
which accumulate and release electric charges to be read out as
signal values according to received radiation and generating a
dynamic image formed of a plurality of frames, and the program
causing the computer to perform: setting an amount of the tube
current; calculating such a proper range of the tube current that
start and end of generation of one of the radiation pulse by the
radiation generator are within one of an accumulation time which is
set in advance to perform an imaging with the set accumulation
time; and regulating setting of a value out of the calculated
proper range.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims priority under 35 U.S.C. .sctn.
119 to Japanese Patent Application No. 2019-218444 filed on Dec. 3,
2019, the entire content of which is incorporated herein by
reference.
BACKGROUND
Technological Field
[0002] The present invention relates to a radiation imaging system,
an imaging control device, and a storage medium.
Description of the Related Art
[0003] The sites of interest to be diagnosed by a person who
performs diagnosis have different movement speeds according to the
positions of the sites and the ways of movement.
[0004] Even for a same site of interest, the image quality required
for a radiation image used in the diagnosis is different according
to the purpose of diagnosis (for example, diagnosis of movement in
breathing or diagnosis of movement of bloodstream, as for a
chest).
[0005] Thus, in dynamic imaging of generating a dynamic image
formed of a plurality of frames by using a radiation generator
which repeatedly generates radiation pulses and a radiation
detector which repeatedly generates radiation images according to
the received radiation, imaging has been conventionally performed
by switching to a desired (according to the site of interest and
the purpose of diagnosis) frame rate from among a plurality of
different frame rates.
[0006] In order to obtain a dynamic image which has no problem in
image quality, it is necessary to generate radiation pulses while
the radiation detector can accumulate electric charges (during
accumulation time).
[0007] Thus, as described in JP 2012-161530 A, for example, there
has been conventionally performed a control in a radiation image
capturing system including a radiation irradiation device and a
radiation image capturing device, the control making the radiation
emitted by pulse irradiation from the radiation irradiation device
to the radiation image capturing device with a rate of irradiation
period to each frame period for capturing each frame image
according to the frame rate of fluoroscopic imaging within a range
of 12.5% to 80%, while causing the radiation image capturing device
to perform capturing of the radiation image in synchronization with
the pulse irradiation.
SUMMARY
[0008] The radiation pulse generated by the radiation generator
does not reach a predetermined dose at the same time as the start
of generating the radiation pulse, and the dose does not reach zero
at the same time as the end of generating the radiation pulse. That
is, there is known that, when the change over time of the dose of
radiation pulse is shown by a graph, the graph does not draw a
rectangle but draws a nearly trapezoid with the rising portion and
the falling portion which are inclined.
[0009] As shown in FIG. 1, the inclination of each of the rising
and falling portions (especially, falling portion) is steep when
the tube current is large, but the inclination is more gradual as
the tube current is smaller.
[0010] However, the conventional radiation imaging system as
described in above JP 2012-161530 A controls the radiation
generator and the radiation detector such that the irradiation time
of the radiation pulse is within the accumulation time. The
irradiation time is generally the time after the radiation pulse
reaches a predetermined dose until the radiation pulse returns to
the same dose.
[0011] That is, in the conventional radiation imaging system, the
inclination property of the radiation pulse as mentioned above is
not considered. Thus, when the dynamic imaging is performed by
setting the tube current to be small, by attempting to make the
irradiation time of the radiation pulse within the accumulation
time, the timing when the generation of radiation pulse starts and
the timing when the generation of radiation pulse ends go out of
the accumulation time, and the dynamic image influenced by this
situation is possibly generated.
[0012] Such a problem is more remarkable as the frame rate is
higher.
[0013] The present invention has been made in consideration of the
above matters, and an object of the present invention is to enable
generating a dynamic image without problem in image quality even
when the tube current is small, in dynamic imaging using a
radiation generator and a radiation detector, the radiation
generator including a radiation source that generates radiation
pulse by receiving supply of a preset amount of the tube current,
and the radiation detector including a plurality of charge
accumulators that accumulate and release electric charges to be
read out as signal values according to the received radiation and
generating a dynamic image formed of a plurality of frames.
[0014] To achieve at least one of the abovementioned objects,
according to an aspect of the present invention, a radiation
imaging system reflecting one aspect of the present invention is a
radiation imaging system including: a radiation generator that
includes a radiation source which generates a radiation pulse by
receiving supply of a tube current of a preset amount; a radiation
detector that includes a plurality of charge accumulators which
accumulate and release electric charges to be read out as signal
values according to received radiation and that generates a dynamic
image formed of a plurality of frames; and a hardware processor
that: sets an amount of the tube current and a length of an
accumulation time for which the charge accumulators are allowed to
accumulate the electric charges; calculates such a proper range of
the tube current that start and end of generation of one of the
radiation pulse by the radiation generator are within one of the
set accumulation time to perform an imaging with the set
accumulation time; and regulates setting of a value out of the
calculated proper range.
[0015] To achieve at least one of the abovementioned objects,
according to another aspect of the present invention, an imaging
control device reflecting one aspect of the present invention is an
imaging control device that controls a radiation generator and a
radiation detector, the radiation generator including a radiation
source which generates a radiation pulse by receiving supply of a
tube current of a preset amount, the radiation detector including a
plurality of charge accumulators which accumulate and release
electric charges to be read out as signal values according to
received radiation and generating a dynamic image formed of a
plurality of frames, and the imaging control device comprising a
hardware processor that: sets an amount of the tube current;
calculates such a proper range of the tube current that start and
end of generation of one of the radiation pulse by the radiation
generator are within one of an accumulation time which is set in
advance to perform an imaging with the set accumulation time; and
regulates setting of a value out of the calculated proper
range.
[0016] To achieve at least one of the abovementioned objects,
according to another aspect of the present invention, a storage
medium reflecting one aspect of the present invention is a
non-transitory storage medium storing a computer readable program
for a computer in an imaging control device that controls a
radiation generator and a radiation detector, the radiation
generator including a radiation source which generates a radiation
pulse by receiving supply of a tube current of a preset amount, the
radiation detector including a plurality of charge accumulators
which accumulate and release electric charges to be read out as
signal values according to received radiation and generating a
dynamic image formed of a plurality of frames, and the program
causing the computer to perform: setting an amount of the tube
current; calculating such a proper range of the tube current that
start and end of generation of one of the radiation pulse by the
radiation generator are within one of an accumulation time which is
set in advance to perform an imaging with the set accumulation
time; and regulating setting of a value out of the calculated
proper range.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The advantages and features provided by one or more
embodiments of the invention will become more fully understood from
the detailed description given hereinafter and the appended
drawings which are given by way of illustration only, and thus are
not intended as a definition of the limits of the present
invention, and wherein:
[0018] FIG. 1 is a graph showing the change over time of the
radiation pulse;
[0019] FIG. 2 is a block diagram showing a radiation imaging system
according to an embodiment of the present invention;
[0020] FIG. 3 is a block diagram showing a radiation detector which
is included in the radiation imaging system in FIG. 2;
[0021] FIG. 4 is a view showing the operation of the radiation
imaging system in FIG. 2 at the time of dynamic imaging;
[0022] FIG. 5 is a block diagram showing an imaging control device
(generator control console) which is included in the radiation
imaging system in FIG. 2;
[0023] FIG. 6 is a flowchart showing the flow of imaging
preparation processing executed by the imaging control device in
FIG. 5;
[0024] FIG. 7 is a flowchart showing the flow of other imaging
preparation processing executed by the imaging control device in
FIG. 5;
[0025] FIG. 8 is a table showing a setting example of the radiation
irradiation condition and the imaging condition for each
accumulation time;
[0026] FIG. 9 is a flowchart showing the flow of other imaging
preparation processing executed by the imaging control device in
FIG. 5;
[0027] FIG. 10 is a graph showing the change over time of the
radiation pulse;
[0028] FIG. 11 is a flowchart showing the flow of other imaging
preparation processing executed by the imaging control device in
FIG. 5;
[0029] FIG. 12 is a table showing another setting example of the
radiation irradiation condition and the imaging condition for each
accumulation time;
[0030] FIG. 13 is a table showing another setting example of the
radiation irradiation condition and the imaging condition for each
accumulation time;
[0031] FIG. 14 is a table showing another setting example of the
radiation irradiation condition and the imaging condition for each
accumulation time;
[0032] FIG. 15 is a table showing another setting example of the
radiation irradiation condition and the imaging condition for each
accumulation time;
[0033] FIGS. 16A and 16B are graphs each showing the change over
time of the temperature of a reading section in the radiation
detector in FIG. 3;
[0034] FIG. 17 is a view showing a manner in which the lag is
generated; and
[0035] FIGS. 18A and 18B are graphs each showing the change over
time of a long time constant lag.
DETAILED DESCRIPTION OF EMBODIMENTS
[0036] Hereinafter, one or more embodiments of the present
invention will be described with reference to the drawings.
However, the scope of the invention is not limited to the disclosed
embodiments or the illustrated examples.
[0037] <1. Configuration of Radiation Imaging System>
[0038] The schematic configuration of a radiation imaging system
according to the present embodiment (hereinafter, referred to as a
system 100) will be first described. FIG. 2 is a block diagram
showing the system 100, FIG. 3 is a block diagram of a radiation
detector (hereinafter, referred to as a detector 2) which is
included in the system 100, FIG. 4 is a timing chart showing the
operation when imaging (hereinafter, referred to as dynamic
imaging) of a dynamic image is performed by using the system 100,
and FIG. 5 is a block diagram of a generator control console 31
which is included in the system 100.
[0039] As shown in FIG. 2, the system 100 includes a radiation
generator (hereinafter, referred to as a generator 1), the
radiation detector (hereinafter, referred to as detector 2), and a
console 3, for example.
[0040] The system 100 according to the present embodiment further
includes an irradiation instruction switch (hereinafter, referred
to as a switch 4), and an additional device 5.
[0041] The system 100 may be communicable to Radiology Information
System (RIS) and Picture Archiving and Communication System (PACS)
via a communication network N (Local Area Network (LAN), Wide Area
Network (WAN), internet or the like).
[0042] [1-1. Radiation Generator]
[0043] The generator 1 includes a radiation control device 11 and a
radiation source 12.
[0044] The radiation control device 11 includes a radiation control
section 111 and a high voltage generating section 112.
[0045] The radiation control section 111 and the high voltage
generating section 112 are electrically connected to each
other.
[0046] The radiation control section 111 controls radiation
irradiation.
[0047] To be specific, in response to turning on of an irradiation
preparation signal which is input from the generator control
console 31, the radiation control section 111 turns on the
irradiation preparation signals which are output to the high
voltage generating section 112 and the additional device 5.
[0048] In response to turning on of the irradiation instruction
signal which is input from the generator control console 31 and
instructs radiation irradiation, the radiation control section 111
turns on the irradiation instruction signal output to the
additional device 5, and transmits the irradiation signal
corresponding to the radiation irradiation condition, which was set
by the generator control console 31, to the high voltage generating
section 112.
[0049] In response to turning on of the irradiation preparation
signal which is input from the radiation control section 111, the
high voltage generating section 112 outputs the irradiation
preparation output to the radiation source 12.
[0050] In response to receiving of the irradiation signal from the
radiation control section 111, the high voltage generating section
112 applies a tube voltage which was set in advance as the
irradiation output to the radiation source 12, and supplies a
preset amount of tube current to the radiation source 12.
[0051] The radiation source 12 (tube) generates radiation (for
example, X-ray) by receiving the supply of the preset amount of
tube current from the high voltage generating section 112.
[0052] The generator 1 which is configured in such a way generates
radiation corresponding to the imaging condition and the radiation
irradiation condition which were set in advance, according to the
signal input from the generator control console 31 (from an
after-mentioned irradiation instruction switch 4).
[0053] [1-2. Radiation Detector]
[0054] As shown in FIG. 3, the detector 2 includes a sensor section
21, a scanning drive section 22, a reading section 23, a control
section 24, a storage 25 and a communicating section 26.
[0055] The above sections 21 to 26 are electrically connected to
each other.
[0056] The sensor section 21 includes a scintillator not shown in
the drawings and a photoelectric conversion panel 211.
[0057] The scintillator is formed in a flat plate shape with a
columnar crystal of CsI, for example.
[0058] By receiving radiation, the scintillator emits
electromagnetic waves (for example, visible light) having a longer
wavelength than the wavelength of radiation, with the intensity
corresponding to the dose of the received radiation (mAs).
[0059] The scintillator is arranged to spread in parallel with the
radiation incidence plane of a housing not shown in the
drawings.
[0060] The photoelectric conversion panel 211 is arranged to spread
in parallel to the scintillator, on the opposite side to the face
of the scintillator facing the radiation incidence plane of the
housing.
[0061] The photoelectric conversion panel 211 includes a substrate
211a and a plurality of charge accumulators 211b.
[0062] The plurality of charge accumulators 211b are arranged two
dimensionally (for example, in a matrix) to correspond to
respective pixels in the radiation image on the surface of the
substrate facing the scintillator.
[0063] Each of the charge accumulators 211b includes a
semiconductor element which generates an electric charge of an
amount corresponding to the intensity of electromagnetic wave
generated by the scintillator, and a switching element which is
provided between the semiconductor element and the wiring connected
to the reading section 23.
[0064] A bias voltage is applied to each semiconductor element from
a power supply circuit not shown in the drawings.
[0065] By switching on/off of the switching element, each of the
charge accumulators 211b accumulates the electric charge to be read
out as a signal value according to the received radiation and
releases the electric charge.
[0066] By applying an on voltage or an off voltage to each of the
scanning lines 211c of the sensor section 21, the scanning drive
section 22 can switch each of the switching elements to an on state
or an off state.
[0067] The reading section 23 reads out, as the signal value, the
amount of electric charges which flow from the charge accumulator
211b via each signal line 211d of the sensor section 21.
[0068] The reading section 23 may perform binning when the reading
section 23 reads out the signal values.
[0069] The control section 24 includes a Central Processing Unit
(CPU) and a Random Access Memory (RAM) not shown in the
drawings.
[0070] The CPU reads out various types of processing programs
stored in the storage 25 and loads them to the RAM, executes
various types of processing in accordance with the processing
programs, and thereby integrally controls the operation of each of
the sections in the detector 2.
[0071] The control section 24 generates image data of a radiation
image on the basis of a plurality of signal values which were read
out by the reading section 23.
[0072] The storage 25 is configured by including an HDD (Hard Disk
Drive), a semiconductor memory, or the like, and stores processing
programs for executing various types of processing, parameters
necessary for executing the processing programs, files and the
like.
[0073] The storage 25 may be configured to be able to store image
data of the radiation image.
[0074] The communicating section 26 is able to transmit and receive
various signals and various types of data (data of the radiation
image, and the like) to and from other devices (for example,
console 3) connected via the communication network N.
[0075] The detector 2 configured in such a way repeats a series of
operations of switching to the accumulating state and switching to
the reading state after a preset accumulation time elapses, each
time an imaging timing signal is received from the additional
device 5.
[0076] The "accumulating state" in the embodiment is a state in
which the off voltage is applied to each of the switching elements,
and the electric charges generated by the semiconductor element are
accumulated in the charge accumulators 211b.
[0077] The "reading state" is a state in which the on voltage is
applied to each of the switching elements, the electric charges
accumulated in the charge accumulator 211b are released, and the
reading section 23 reads out the amount of the electric charges
which flow in from the charge accumulators 211b as signal
values.
[0078] The detector 2 generates the dynamic image formed of a
plurality of frames by repeating the accumulating state and the
reading state.
[0079] The detector 2 transmits the generated data of the dynamic
image to the console 3 as needed.
[0080] [1-3. Console]
[0081] As shown in FIG. 2, the console 3 includes the generator
control console 31 and the detector control console 32.
[0082] The generator control console 31 and the detector control
console 32 may be integrated as a single device.
[0083] (1-3-1. Generator Control Console)
[0084] The generator control console 31 in the present embodiment
forms an imaging control device.
[0085] The details of the generator control console 31 will be
described later.
[0086] (1-3-2. Detector Control Console)
[0087] The detector control console 32 mainly controls the detector
2.
[0088] The detector control console 32 is able to set subject
information (subject name, sex, age, build, site of interest, and
the like) and imaging conditions (accumulation time, frame rate,
maximum imaging number, number of binning, and the like) in the
detector 2.
[0089] The "accumulation time" is a period during which the charge
accumulators 211b can accumulate electric charges (until the
switching elements of the charge accumulators 211b turn into the on
state (conducted state between the semiconductor elements and the
reading section 23) after the switching elements turn into the off
state (non-conducted state between the semiconductor elements and
the reading section 23)).
[0090] The "maximum imaging number" is the maximum number of frames
which are generated by the detector 2 in a single dynamic
imaging.
[0091] The detector control console 32 is able to transmit the
subject information and the imaging conditions which are set in the
detector 2 to the generator control console 31.
[0092] The detector control console 32 is also able to set the
operation (the period and the number of times as for outputting the
irradiation timing signal, and the like) of the additional device 5
in the additional device 5.
[0093] The detector control console 32 may change the frame rate
which is set according to the set accumulation time, or may not
change the frame rate (may maintain a constant frame rate
irrespective of the accumulation time).
[0094] The detector control console 32 may be able to set the
radiation irradiation condition of the generator 1.
[0095] The detector control console 32 may receive the radiation
irradiation condition and the like from the generator control
console 31.
[0096] [1-4. Irradiation Instruction Switch]
[0097] The switch 4 is for a person who performs the imaging to
instruct the radiation irradiation.
[0098] The switch 4 in the present embodiment is configured to
allow the two-step operation. To be specific, when the switch 4 is
pressed to the first step, the switch 4 turns on the irradiation
preparation signal to be output to the generator control console
31. When the switch 4 is pressed to the second step, the switch 4
turns on the irradiation instruction signal to be output to the
generator control console 31.
[0099] FIG. 1 illustrates a configuration in which the switch 4 is
connected to the generator control console 31 and the irradiation
preparation signal and the irradiation instruction signal output by
the switch 4 are input to the radiation control section 111 via the
generator control console 31. However, the switch 4 may be
connected to the radiation control section 111 so that the
irradiation preparation signal and the irradiation instruction
signal are directly input to the radiation control section 111.
[0100] [1-5. Additional Device]
[0101] The additional device 5 includes an additional control
section 51 and a communicating section not shown in the
drawings.
[0102] The additional control section 51 integrally controls the
operations of the sections in the additional device 5 with a CPU, a
RAM and the like.
[0103] In this configuration, the additional control section 51
reads out various processing programs stored in a storage not shown
in the drawings to load them to the RAM, and executes the various
types of processing in according with the processing programs.
[0104] The communicating section obtains the irradiation
preparation signal output by the switch 4 via the radiation control
section 111 (generator).
[0105] The communicating section obtains the irradiation
instruction signal output by the switch 4 via the radiation control
section 111 (generator).
[0106] The communicating section receives input of an imaging start
signal from the detector 2.
[0107] The imaging start signal is turned on when the detector 2
comes into a state capable of imaging, and the imaging start signal
is turned off when the detector 2 comes into a state not capable of
imaging.
[0108] The communicating section is able to output the irradiation
timing signal to the radiation control section 111.
[0109] The additional device 5 configured in such a way is able to
repeatedly, at a predetermined period, output the irradiation
timing signal that instructs irradiation of radiation to the
radiation control section 111 via the communicating section
according to the irradiation instruction signal which was obtained
from the radiation control section 111 via the communicating
section and the imaging start signal which was input from the
detector 2 via the communicating section.
[0110] The additional device 5 outputs the imaging timing signal
instructing the imaging timing of the radiation image from the
communicating section to the detector 2 according to the timing to
output the irradiation timing signal.
[0111] The additional device 5 in the present embodiment repeatedly
outputs the imaging timing signal at a same period as the period of
the irradiation timing signal.
[0112] The additional device 5 repeatedly outputs the irradiation
timing signal and the imaging timing signal until the signals are
output a predetermined number of times or until a predetermined
time has elapsed from the first outputting.
[0113] [1-6. Operation]
[0114] In the system 100 configured in such a way, the generator 1
and the detector 2 start dynamic imaging when the dynamic imaging
is set as one of the imaging conditions in the console 3 and the
irradiation instruction switch 13 is pressed by the user.
[0115] In the dynamic imaging, as shown in FIG. 4, for example, the
detector 2 repeats at a preset frame rate a series of operations of
switching to the accumulating state for a preset accumulation time
and then switching to the reading state.
[0116] Each time the detector 2 switches to the accumulating state
(at a preset frame rate), the generator 1 repeatedly emits the
radiation pulse of a preset irradiation time to the subject and the
detector 2 behind the subject.
[0117] The generator 1 and the detector 2 repeat such operations
until the detector 2 generates the preset maximum imaging number of
frames or until the preset imaging time elapses.
[0118] The detector 2 generates a dynamic image formed of a
plurality of frames.
[0119] <2. Generator Control Console>
[0120] Next, the details of the generator control console 31
included in the console 3 of the system 100 will be described.
[0121] FIG. 5 is a block diagram showing the generator control
console 31, FIG. 6 is a flowchart showing the flow of imaging
preparation processing executed by the control section 311 of the
generator control console 31, and FIG. 8 is a table showing a
setting example of the radiation irradiation condition and the
imaging condition for each accumulation time.
[0122] [2-1. Configuration]
[0123] As shown in FIG. 5, the generator control console 31
includes a control section 311 (hardware processor), a
communicating section 312, a storage 313, a display section 314,
and an operating section 315.
[0124] The control section 311 is configured by including a CPU, a
RAM, and the like.
[0125] The CPU of the control section 311 reads out various
programs stored in the storage 313 and loads them to the RAM,
executes various types of processing in accordance with the loaded
programs, and controls the operations of the sections in the
generator control console 31 in a centralized manner.
[0126] The communicating section 312 is configured by including a
wired communication module, a wireless communication module, or the
like. The communicating section 312 is able to transmit and receive
in a wired manner or wirelessly various signals and various types
of data to and from other devices (generator 1, detector 2 and the
like) connected via the communication network N.
[0127] The storage 313 is configured by including a nonvolatile
semiconductor memory, a hard disk, or the like.
[0128] The storage 313 stores programs for the control section 311
to execute various types of processing, parameters necessary for
executing the programs, and the like.
[0129] The storage 313 in the present embodiment is able to save
the image data of the radiation image.
[0130] The image data may be saved by a saving section which is
provided separately from the storage 313.
[0131] The display section 314 is configured by including a monitor
such as an LCD (Liquid Crystal Display) and a CRT (Cathode Ray
Tube). The display section 314 displays various images and various
types of information and the like in accordance with instructions
of display signals input from the control section 311.
[0132] The operating section 315 is configured to be operated by
the user with a keyboard including cursor keys, numeric input keys,
various types of function keys, and the like, a pointing device
such as a mouse, a touch panel which is layered on the surface of
the display section 314, or the like.
[0133] The operating section 315 outputs a control signal based on
the operation which was made by the operator to the control section
311.
[0134] [2-2. Operation]
[0135] The control section 311 of the generator control console 31
which is configured in such a way includes the following
function.
[0136] For example, the control section 311 has a function of
setting the radiation irradiation conditions (tube voltage, tube
current, irradiation time, and the like) in the radiation control
section 111 on the basis of the operation made to the operating
section 315 by the user.
[0137] The control section 311 has a function of outputting, to the
radiation control device 11, the irradiation preparation signal and
the irradiation instruction signal which were input from the switch
4.
[0138] The control section 311 has a function of obtaining
information (for example, imaging conditions which are set, or the
like) held by the detector control console 32 via the communicating
section 312.
[0139] The control section 311 may have a function of outputting
information (for example, radiation irradiation condition which is
set in the control section 311 itself, or the like) held by the
storage 313 via the communicating section 312.
[0140] [2-3. Imaging Preparation Processing]
[0141] The control section 311 includes a function of executing
imaging preparation processing as shown in FIG. 6 or 7 when the
dynamic imaging is set as an imaging mode which is one of the
imaging conditions obtained from the detector control console
32.
[0142] (2-3-1. Obtaining Process)
[0143] In this imaging preparation processing, the control section
311 first executes an obtaining process (step S1).
[0144] In the obtaining process, the control section 311 obtains
the length of the accumulation time from another device (for
example, detector control console 32).
[0145] This "obtaining" includes receiving of a value transmitted
from another device (for example, detector control console 32),
directly inputting of a value to the generator control console 31
by the user, and the like.
[0146] The control section 311 in the present embodiment obtains
the imaging conditions (imaging time, maximum imaging number, and
frame rate) in addition to the accumulation time.
[0147] The control section 311 forms a setter by executing the
process of step S1.
[0148] (2-3-2. Tube Current Calculation Process)
[0149] After the accumulation time is set, the control section 311
executes a tube current calculation process (step S2).
[0150] In the tube current calculation process, the control section
311 calculates such a proper range of the tube current that the
start and end of the generation of one radiation pulse by the
generator 1 are within one accumulation time when the imaging is
performed with the accumulation time which was set in step S1.
[0151] The control section 311 in the present embodiment performs
the calculation such that the upper limit value of the proper range
is a fixed value and the lower limit value of the proper range is
lower as the accumulation time is longer as shown in FIG. 8, for
example.
[0152] By defining the start and end of generating the radiation
pulse in such a way, the irradiation time of radiation becomes the
time considering the inclination property of the radiation
pulse.
[0153] The control section 311 forms a calculator by executing the
process of step S2.
[0154] (2-3-3. Setting Process)
[0155] After the proper range of the tube current is calculated,
the control section 311 executes a setting process.
[0156] In the setting process, the control section 311 sets the
amount of the tube current.
[0157] When the setting process is executed, the control section
311 regulates setting of values out of the calculated proper
range.
[0158] The way to set the amount of tube current is, for example,
selection of an option or input of a numerical value.
[0159] When the amount of tube current is set by the selection of
an option, as shown in FIG. 6, the control section 311 causes the
display section 314 to display options of values within the proper
range among the options of values which can be set as the amount of
tube current (step S3), and the control section 311 sets, as the
amount of tube current, the option of a value which was selected by
the user from among the options displayed by the display section
314 (step S4).
[0160] Instead of displaying only the options of values within the
proper range (not displaying the options of values out of the
proper range), the regulation may be performed as in the following
way, for example.
[0161] (A) gray down the options of the values out of the proper
range (display options of values within the proper range by normal
displaying)
[0162] (B) not receiving the selection operation performed to the
options of the values out of the proper range
[0163] (C) notify the error (that the input value is out of the
proper range) when an option of the value out of the proper range
is selected
[0164] When the amount of tube current is to be set by the input of
a numerical value, as shown in FIG. 7, the control section 311
receives the input of an arbitrary value by the user (step S5), and
determines whether or not the arbitrary value which was input by
the user is within the proper range (step S6). If the control
section 311 determines that the input value is within the proper
range (step S6; YES), the control section 311 sets the value which
was input by the user as the amount of tube current (step S4A). On
the other hand, if the control section 311 determines that the
input value is out of the proper range (step S6; NO), the control
section 311 notifies the error (step S7).
[0165] Instead of notifying the error, the regulation may be
performed as in the following way, for example.
[0166] (a) request inputting a value again
[0167] (b) stop the operation of at least one device forming the
system 100
[0168] The above regulation methods are examples, and the
regulation may be performed by using other methods.
[0169] The error may be notified by displaying characters or may be
notified by sound.
[0170] The notification of error may be performed by the generator
control console 31 itself, or the instruction to notify the error
may be output to another device to cause the another device to
perform the notification.
[0171] The control section 311 forms a setter, a regulator, and a
notifier by performing the above controls.
[0172] The control section 311 in the present embodiment sets the
tube voltage and the irradiation time.
[0173] The way to set the tube voltage and the irradiation time may
be similar to the way to set the tube current, or may be different
from the way to set the tube current.
[0174] When the above-described imaging preparation processing is
executed, the generator 1, the detector 2 and the additional device
5 come into a state able to perform the dynamic imaging (standby
state of waiting for reception of the irradiation preparation
signal and the irradiation instruction signal from the irradiation
instruction switch).
[0175] Other devices (for example, detector control console 32) may
include the function as the imaging control device.
[0176] The respective functions as the calculator, the setter, and
the regulator may be dispersed in the system 100.
[0177] <3. Effect>
[0178] As described above, when imaging is performed with a set
accumulation time, the system 100 in the present embodiment
calculates such a proper range of the tube current that the start
and end of generating one radiation pulse by the generator 1 are
within one accumulation time, and regulates setting of values out
of the calculated proper range. That is, the irradiation time of
the radiation pulse is set to be a time considering the inclination
property of the radiation pulse.
[0179] As a result, it is possible to generate the dynamic image
which has no problem in quality even when the tube current is
small.
[0180] <4. Additional Techniques>
[0181] Next, various techniques to be added to the above system 100
will be described.
[0182] The following various techniques can also be applied to
radiation imaging systems (not having the functions as the
calculator and the regulator) other than the above system 100.
[0183] [4-1. Additional Technique 1]
[0184] As shown in FIG. 9, the control section 311 may obtain the
imaging conditions set in the detector control console 32 from the
detector control console 32 (step S8), and determine whether the
value of at least one of the accumulation time and the frame rate
set in the generator 1 matches the value of the at least one of the
accumulation time and the frame rate set in the detector 2 (step
S9).
[0185] If the control section 311 determines that the value set in
the generator 1 matches the value set in the detector 2 (step S9;
YES), the control section 311 may output a permission to perform
imaging to at least one of the generator 1 and the detector 2. If
the control section 311 determines that the value set in the
generator 1 does not match the value set in the detector 2 (step
S9; NO), the control section 311 may output an instruction to
notify the error (step S10).
[0186] The control section 311 may not output the permission to
perform imaging, but perform the process to be performed before
imaging (for example, calculation of proper range).
[0187] By such a configuration, the control section 311 forms a
determiner, and it is possible to prevent imaging from being
performed in a state in which the imaging conditions set in the
generator 1 and the detector 2 are different from each other.
[0188] [4-2. Additional Technique 2]
[0189] When imaging is performed to a site which does not easily
transmit radiation or a subject which has a large body thickness,
it is necessary to increase the tube voltage in order to shorten
the wavelength of radiation.
[0190] When the change over time of the dose of radiation pulse is
graphed, a nearly trapezoid is drawn with inclined rise and fall as
mentioned above, and the inclinations of rise and fall (especially,
fall) depend on not only the tube current but also the tube
voltage. To be specific, as shown in FIG. 10, the inclination is
steep when the tube current is small, but the inclination becomes
more gradual as the tube voltage is larger. This is because more
electric charges are supplied to the radiation source 12 (Q=CV) as
the tube voltage is larger, and it takes time for the electric
charges which were collected in the radiation source 12 to be taken
away from the radiation source 12 after stop of the applying of the
tube voltage.
[0191] Thus, in the above system 100, there is a possibility that
when the dynamic imaging is performed by setting a large tube
voltage, the timings to start and end the generation of radiation
pulse cannot be within the accumulation time in the attempt to make
the irradiation time of radiation pulse within the accumulation
time, and the dynamic image influenced by that (failing to have the
start and the end of generation of radiation pulse within the
accumulation time) is generated.
[0192] Such a problem is more remarkable as the frame rate is
higher.
[0193] After the process of step S1, as shown in FIG. 11, for
example, the control section 311 may calculate the proper range of
the value of at least one of the tube voltage and the irradiation
time according to the length of the set accumulation time, in
addition to the proper range of tube current (step S2A).
[0194] For example, as shown in FIG. 12, calculation is performed
to have a fixed lower limit value of the proper range of each of
the tube voltage and the irradiation time and to have the upper
limit value of the proper range lowered as the accumulation time is
shorter.
[0195] The control section 311 may regulate setting of the tube
current out of the proper range, and may regulate setting of the
value of at least one of the tube voltage and the irradiation time
out of the proper range (step S11).
[0196] The method to regulate the value setting may be similar to
the method to regulate the value setting of the tube current
mentioned above.
[0197] By such a configuration, it is possible to not only generate
the dynamic image which has no problem in quality even when the
tube current is small, but also generate the dynamic image which
has no problem in quality even when the tube voltage is large.
[0198] As a result, it is possible to increase the site for which
imaging can be performed, and it is possible to perform dynamic
imaging of a subject which has a large body thickness.
[0199] [4-3. Additional Technique 3]
[0200] When a total dose of radiation emitted in one dynamic
imaging is increased, there is a problem that the load on the
generator 1 is increased and the life of generator 1 is
shortened.
[0201] Thus, as shown in FIG. 13, for example, when a second value
larger than a first value is set as a value of at least one of
parameters among the tube current, the tube voltage and the
irradiation time (only the irradiation time in FIG. 13), the
control section 311 may lower the value(s) of parameter(s) which
was not set to the second value among the tube current, the tube
voltage and the irradiation time so that the total dose in one
dynamic imaging does not exceed the total dose when the first value
is set.
[0202] In this configuration, it is preferable to limit such that
the total dose in a single imaging of the dynamic image is equal
when the first value is set and when the second value is set (when
the first value is n times the second value (n>1), set the value
of other parameter(s) to 1/n).
[0203] By such a configuration, it is possible to prevent the lives
of the generator 1 and the detector 2 from being shortened.
[0204] [4-4. Additional Technique 4]
[0205] When dynamic imaging is performed for the movement of a
joint or the like, there may be a difference in imaging time among
individuals depending on the treatment performed to the subject
before the imaging (for example, reducing). Such a difference among
individuals can be dealt with when the system 100 is made for long
time dynamic imaging. However, the long time dynamic imaging has a
larger exposure amount of the subject than the exposure amount of
the short time dynamic imaging.
[0206] Thus, as shown in FIG. 14, for example, when a fourth value
larger than a third value is set as a value of at least one of
parameters among the maximum imaging time, the maximum imaging
number and the dose of one radiation pulse (in FIG. 14, only the
maximum imaging time), the control section 311 may lower the
value(s) of parameter(s) for which the fourth value is not set
among the maximum imaging time, the maximum imaging number and the
dose of one radiation pulse so that the total dose in one dynamic
imaging does not exceed the total dose when the third value is
set.
[0207] In this configuration, it is preferable to limit such that
the total dose in a single imaging of the dynamic image is equal
when the third value is set and when the fourth value is set (to
set other parameter(s) to 1/n when the third value is n times
(n>1) the fourth value).
[0208] By such a configuration, even when the dynamic imaging is
performed for a relatively long time, it is possible to suppress
the exposure amount of the subject. As a result, it is possible to
deal with imaging times which are different by the subject.
[0209] [4-5. Additional Technique 5]
[0210] In the dynamic imaging, it is necessary to change the frame
rate when the dynamic imaging is performed, according to the site
of interest, and how the site of interest moves and the speed of
the movement.
[0211] On the other hand, even for a same site of interest, a
different image quality is required for the dynamic image according
to the purpose of diagnosis. For example, in the diagnosis of
orthopedic field, a highly detailed dynamic image is required
depending on the site of interest, while there are also sites of
interest which do not require a high image quality. That is, not
only the proper accumulation time and frame rate, but also the
proper pixel pitch is necessary.
[0212] Thus, in the above system 100, as shown in FIG. 15, the
binning number (frame rate/pixel pitch) to be set of the binning
performed when the detector 2 reads out the signal value may be
changed according to the set site of interest.
[0213] By such a configuration, it is possible to provide a highly
detailed dynamic image as needed.
[0214] [4-6. Additional Technique 6]
[0215] When there are a plurality of generators 1, the property
(actual irradiation time, tube voltage, tube current, total dose,
and the like with respect to the set contents) is different by the
generator 1 (manufacturer, and the like). Thus, when the generator
1 to be used is changed, there may be a difference in image quality
of the obtained dynamic image even when the setting on the
generator control console 31 is same.
[0216] Thus, in the above system 100, the connected generator 1 may
be identified to adjust the proper range of the calculated value
according to the identified generator 1.
[0217] The identifying of the generator 1 may be performed
automatically by the system 100, or may be performed by a person
who performs setup of the system 100 (serviceman of the
manufacturer, or the like) performing a predetermined operation
(selection of presetting).
[0218] By such a configuration, the control section 311 forms a
device identifier, and it is possible to perform appropriate
dynamic imaging even when the connected generator 1 is changed.
[0219] [4-7. Additional Technique 7]
[0220] As mentioned above, in the dynamic imaging, it is necessary
to change the frame rate when the dynamic imaging is performed,
according to the site of interest, and how the site of interest
moves and the speed of the movement.
[0221] Thus, when the dynamic imaging is performed by setting the
frame rate not considering the dynamic state speed, there is a
possibility that the information necessary for diagnosis is not
obtained from the obtained dynamic image and imaging needs to be
performed again. The re-imaging leads to excessive exposure of the
subject.
[0222] Thus, in the above system 100, the speed of a specific
movement of the subject during imaging of the dynamic image may be
detected so as to change the accumulation time and the frame rate
to be set according to the detected speed.
[0223] The speed can be detected by the detector control console 32
obtaining a plurality of frames which were generated by the
detector 2 and obtaining the difference in signal value between two
frames, for example.
[0224] By such a configuration, the detector control console 32
forms a speed detector, and it is possible to have a proper dose of
radiation according to the speed of specific movement of the
subject.
[0225] [4-8. Additional Technique 8]
[0226] The point to focus on regarding the frame changes according
to the test purpose (movement of the subject to be diagnosed). For
example, the movement between consecutive frames may be diagnosed,
or non-consecutive frames (for example, first and 100.sub.th
frames) may be compared.
[0227] It is known that the detector 2 requires time to some extent
until the temperature change of the reading section 23 causing heat
noise is stabilized after the detector 2 is activated and starts
warming up (operation of repeating the reading of signal value
before starting the imaging of dynamic image), as shown in FIG.
16A.
[0228] When non-consecutive frames are compared, the difference in
heat noise is large. Thus, it is necessary to compare frames (for
example, the frames generated at the timings a and b in FIG. 16A)
which were generated after the temperature change of the reading
section 23 stabilizes. On the other hand, when the movement between
consecutive frames is diagnosed, the difference in heat noise
between the frames is small Thus, the influence on diagnosis is
small even when the comparison is made between the frames (for
example, the frames generated at the timings c and d in FIG. 16A)
which were generated before the temperature change of the reading
section 23 stabilizes. It is a waste of time to wait until the
temperature change of the reading section 23 stabilizes to perform
imaging in such a situation (that is, when the movement between
consecutive frames is diagnosed).
[0229] Thus, in the above system 100, the console 3 may set a test
purpose and set the length of warmup period according to the test
purpose which was set.
[0230] To be specific, when consecutive frames are compared, as
shown in FIG. 16B, the warmup period is shortened.
[0231] By such a configuration, it is possible to set the warmup
period of a proper length according to the test purpose, and raise
the efficiency of dynamic imaging.
[0232] [4-9. Additional Technique 9]
[0233] In the dynamic imaging, there may occur the phenomenon
called lag in which the electric charges when generating a frame
(referred to as a previous frame) influence the following frame.
This lag mostly occurs in the form of superposing the image shadow
of the previous frame on the following frame as shown in FIG.
17.
[0234] One of the causes of the lag is a component (long time
constant lag) which attenuates with a relatively long time constant
(approximately several seconds) after reception of radiation
irradiation.
[0235] The long time constant lag can be removed by performing the
weighted difference processing using the previous frame to the
target frame. However, since the long time constant lag is a
function which depends on time, the generation amount is larger as
the frame rate is smaller (integration time is longer) as shown in
FIG. 18A and FIG. 18B.
[0236] Thus, in the above system 100, the weighting coefficient of
the lag correction processing may be switched according to the set
frame rate.
[0237] By such a configuration, it is possible to appropriately
correct the lag which is different in the degree of generation
according to the frame rate of the imaging.
[0238] The lag correction has a demerit of increasing the image
noise due to the difference processing. The lag has a property that
the visibility is high in imaging of the lateral face of a body
trunk which is imaging with a thick subject and with a large
difference in signal value between the direct transmitting region
and the site of interest, and that the visibility is low in imaging
of a thin subject such as limbs.
[0239] Thus, it is desirable to perform the lag correction to only
the imaging which requires correction.
[0240] Accordingly, the on/off may be switched for even the same
frame rate when the lag is not a problem clinically by the imaging
site, positioning and the site of interest.
[0241] [4-10. Additional Technique 10]
[0242] In order to improve granularity of the dynamic image and
reduce the lateral noise, inter-frame image correction processing
(for example, recursive filter) can be performed to each frame.
[0243] However, when the dynamic imaging is performed by changing
the frame rate and/or the imaging site (speed of movement) and the
same inter-frame image processing is performed to the generated
dynamic image, the artifact may occur due to the processing.
[0244] Thus, in the above system 100, the coefficient of the
recursive filter may be switched according to the set frame rate
and/or imaging site.
[0245] By such a configuration, even when the dynamic imaging is
performed by changing the frame rate and/or the imaging site, it is
possible to improve the image quality while preventing the
generation of artifact in the dynamic image.
[0246] [4-11. Additional Technique 11]
[0247] The wireless communication may lack in stability compared to
the wired communication. Thus, it may take time to transfer the
data of the dynamic image from the detector 2 to the console 3, or
the transferring may be impossible.
[0248] When the data transferring is delayed, the image
confirmation regarding whether or not the reimaging performed after
the imaging is necessary is delayed. Thus, the subject needs to
wait for a long time, and the burden on the subject is
increased.
[0249] Thus, when the communication between the detector 2 and the
console 3 is performed wirelessly in the above system 100, setting
of a frame rate which is relatively high may be regulated to reduce
the data amount to be transferred.
[0250] The frame rate with which the data of dynamic image can be
transmitted without delay even by the wireless communication may be
calculated on the basis of the current communication state (such as
actual throughput when the communication is actually performed) and
the calculated frame rate may be notified.
[0251] When the delay and the like cannot be resolved by changing
the frame rate as a result of the calculation of frame rate, the
notification urging the wired imaging may be performed.
[0252] By such a configuration, it is possible to surely transfer
the data of dynamic image in a short time even by the wireless
communication.
[0253] [4-12. Additional Technique 12]
[0254] When the processing performance of devices forming the
system 100 is not sufficient (for example, the console or the like
mounted on the visiting car for a doctor's round often has a low
processing performance compared to the processing performance of a
console or the like set in the imaging room), it may take time to
transfer the data of dynamic image of a high frame rate from the
detector 2 to the console 3 or to perform image processing to the
dynamic image in the detector 2 and the console 3.
[0255] When the transfer of data and the image processing are
delayed, the image confirmation regarding whether or not the
reimaging performed after imaging is necessary is delayed. Thus,
the subject needs to wait for a long time, and the burden on the
subject is increased.
[0256] Thus, in the above system 100, at least one of the upper
limit and the lower limit of the frame rate when the dynamic
imaging is performed may be calculated according to the processing
performance of the console 3 (core number of the control section
311, memory capacity, or the like) and setting of frame rates out
of the calculated range may be regulated.
[0257] By such a configuration, it is possible to finish the work
from the dynamic imaging to the image confirmation in a short time
irrespective of the imaging environment (for example, the
processing performance of device which is different between
doctor's round and general imaging).
[0258] [4-13. Additional Technique 13]
[0259] The maximum imaging number of the dynamic image greatly
depends on the memory capacity of the detector 2. Thus, in the
above system 100, the dynamic imaging at the set frame rate cannot
be performed depending on the memory in the detector 2.
[0260] Thus, in the above system 100, the imaging time and the
frame rate may be determined according to the memory capacity of
the detector 2.
[0261] By such a configuration, it is possible to perform dynamic
imaging appropriate for the connected detector 2.
[0262] Although embodiments of the present invention have been
described and illustrated in detail, the disclosed embodiments are
made for purposes of illustration and example only and not
limitation. The scope of the present invention should be
interpreted by terms of the appended claims.
* * * * *