FI118395B - Imaging arrangement used in Intra-oral X-ray imaging, has inductive power and data receiver and transmitter, radio frequency (RF) transmitter and receiver arranged to supply sensor with energy in connection with imaging event - Google Patents

Abstract

Inductive power and data receiver (33), inductive power and data transmitter (43), radio frequency (RF) transmitter (36) and RF receiver (46), arranged to function as a wireless transmission link to supply a sensor (30) with energy in connection with an imaging event, transmit image data detected by the sensor to a base station (40). Independent claims are also included for the following: (A) a wireless electric receiver of image data; (B) a base station for intra-oral X-ray sensor; (C) a method of using an X-ray imaging sensor; and (D) a method of transferring data to an intra-oral X-ray sensor and from a sensor.

Description

118395

FIELD OF THE INVENTION

The present invention relates to an x-ray imaging, in particular an imaging arrangement for intra-x-ray imaging, a wireless imaging sensor and a sensor base station, and methods for operating a sensor and transmitting data to and from the sensor wirelessly.

BACKGROUND OF THE INVENTION

Intra-oral X-rays are taken using X-ray examination equipment, which typically includes, on the one hand, a multi-jointed arm structure and a radiation source associated therewith, and, on the other hand, image data receiving means positioned in the mouth. In general, electronic imaging sensors based on, for example, CCD or CMOS technology have become increasingly popular alongside the use of conventional film.

To enable electronic intraoral imaging, an oral positioning sensor must be able to, on the one hand, measure its required power and, on the other hand, retrieve it from the image or, for example, display the image information it represents. In addition, you must be able to identify *; · '! at least the start of imaging, that is, the start of radiation ···. In the earliest electronic intraoral X-ray · * ··. ···. 30 gen wires used wires not only for supplying ♦ · · electric power, but also for example. for transmitting synchronization signals of the radiation source and the sensor. Since then, "I * solutions have been developed in which, for example, the onset of irradiation can be detected by a signal directly from the sensor ·· * · .. 35, whereby the synchronization between the sensor and the radiation source via a cable has ceased to exist. However, the sensor cable was still needed to supply power to the 118395 on the one hand and to transmit image and sensor control information on the other hand.

In intra-x-ray imaging, the sensor has to be repeatedly repositioned in different positions in the patient's mouth. In this connection, the sensor cable bends, whereby both the cable itself and its connection to the sensor are repeatedly exposed to forces that easily wear out the cable, and in particular its sensor connection. Indeed, it is quite typical 10 that the life of the cable is shorter than that of the sensor itself. Although, in intraoral imaging arrangements, the sensor cable itself, when properly arranged, can also provide a security means to reduce the likelihood that a relatively expensive sensor will fall to the floor and thereby break, but many other fields have also begun to develop solutions based on wireless technology.

One of the key features of the practical implementation of a wireless intraoral sensor is its low power consumption. Whereas previously it has been possible to achieve diagnostically good image quality only with CCD sensor technology, which is characterized by moderately high power consumption and complicated electronics - not least due to the many different voltage levels required, not · '**; wireless intraoral X-ray was practically feasible before the development of other technologies, such as CMOS sensors, had reached a sufficiently high level. an level.

«« «· ::: 30

• I

*** One boundary condition for intraoral X-ray imaging is also the size of the sensor, which for obvious reasons cannot be <·· ...! very large both in area and thickness.

· · ·

On the other hand, the sensor placed in the patient's mouth must * ί1. 35 in any case be able to supply its supplies, ···. joking power, and on the other hand, the image information that it * * 1 needs to be displayed or captured from the sensor. In addition, it was advantageous if, for example, control signals could be transmitted in the direction of the sensor.

Thus, in the first generation of electronic intraoral sensors 5, data and power transmission was carried out via wires when the technology was not yet sufficiently advanced for wireless data transmission or for the use of wireless technology in general. Subsequent wired arrangements are typically based on the use of a base station in which the battery or capacitor arranged in the 10 sensors is charged either by physical electrical connection between the base station and the sensor or by an induction current. Removable batteries can also be used with the sensors. At least an RF link is used to transfer information from the sensor. For these 15 known solutions reference may be made, for example, to US Patent No. 6,527,442 and JP Application Publication No. 2003-79617. For example, the latter illustrates an imaging system for use in intraoral X-ray imaging, wherein the battery or accumulator 20 used as a sensor power source is disposed in an external sensor unit which is connected to the sensor via a cable. The battery can be charged at the base unit of the holder unit. The image information can be transmitted from the sensor via the holding unit, either when connected to its base station or wirelessly by radio technology. Wireless M *!,! · 25 communication can be arranged either between the sensor and the base station: *** or directly with the PC, for example ·· *; ***; With Bluetooth technology. If the battery can be made small enough, it can also be placed inside the sensor.

• · · 30 The digital wireless digital sensors currently on the market have certain features that are good to get rid of or improve. First of all, the use of batteries as a power source for the sensor not only causes the battery to be replaced from time to time, but also the | *. # T 35 sensor is virtually impossible to arrange such peas- , ···. To be sealed to allow its effective cold sterilization • i "(immersion in liquid). On the other hand, for example, when using a battery or capacitor, they must be recharged periodically before, or between, the imaging event. This may lead to situations where downloading has to be expected - especially when the imaging arrangement would already have to be implemented for radiation hygiene reasons 5 so that imaging cannot even begin if it is possible that the energy charged to the sensor is insufficient to safely capture the image and sensor or forwarded.

10 The small sensor size required for intraoral imaging is also problematic from the point of view of wireless data transmission, because the RF technology that enables sufficiently fast image information and especially bidirectional data transfer using modern technology is relatively large and requires relatively high power. The use of bidirectional RF links also requires relatively sophisticated electronics. On the other hand, if the communication from the sensor is arranged to be only one-way, for example by transmitting the image information from the sensor to the receiver in real time, the image transfer is not possible if necessary, but simply having to rely on communication. Interference with radio frequency communications may be caused, for example, by the long distance between the patient's mouth sensor ··· V 1 25 (through soft tissue) and GSM phones and ··· other high frequency (> 10 MHz) radio transmitters (Bluetooth, WLAN) or other high power radio frequency equipment ·····. If for some reason the power supply does not have enough power to complete the whole imaging event and the transmission of image information ····. ···. 30 is only available in real time, the whole description may need to be taken.

··· • ;; i Sensors may need to be used in multiple locations.

· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · Even in this case, however, it is possible to somehow control which frequency or channel can be used at any one time.

Thus, it is an object of the present invention, with its preferred embodiments, to provide opportunities for reducing or avoiding many of the above problems and limitations. In particular, it is an object of the invention to reduce the problems associated with the use of batteries on the one hand and wireless intraoral imaging based on preloadable sensors on the other.

BRIEF DESCRIPTION OF THE INVENTION

The essential features of the invention are set forth in the appended claims. In various embodiments of the invention, the imaging sensor does not need to be pre-loaded for imaging when it can be powered, if required, also in connection with the imaging event itself. The sensor is provided for use without physical contact on any electrical power or communication bus and, for example, is activated when brought into the operating range of the wireless power transmission transmitter. Preferably, the transmitter transmitting wireless energy to the sensor is integrated, for example, with the radiation source, whereby the arrangement of the corresponding receiver in the sensor can be realized, for example, so that radiation is possible. list only when the sensor is within the short-range operating range of the power transmission line in question.

• ·

The invention, with its preferred embodiments, facilitates the treatment f ···. ···. 30 external self-image workflow • procedures without the need to worry about batteries. and before loading the sensor before the ··· * ”· imaging event.

It is possible to implement the intraoral sensor according to the invention without any hatches or gaps hermetically. closed, which also allows sterilization by sterile • · * · * | by immersion in the fluid.

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The imaging arrangement can advantageously be implemented by using an inductive transmitter for power transmission, which can also be used to provide information to the sensor. It is also possible to utilize the magnetic field generated by the induction loop transmitter to position the sensor at a desired position relative to the beam emitted from the radiation source.

If the sensor is provided operable only in the immediate vicinity of the power transmission transmitter, an RF link in which the transmitter power is significantly low may be used to transmit the image information from the sensor. Further, by using directional antennas and providing the RF link receiver with a high degree of insensitivity and / or positioning within the X-ray source (metal) beam limiter, it is possible to obtain quite good immunity to interference from other devices such as GSM phones. Thus, one embodiment of the invention provides a solution in which data communication can operate reliably under different operating conditions and multiple sensors can be used in the same mode without necessarily interfering with each other.

The invention also allows the sensor to be implemented in a relatively small size, but still be able to wirelessly receive and transmit information, i.e., bidirectionally, in its imaging mass.

* · Φ Φ · • «• · · * m m

Other objects of the invention and some of its preferred embodiments will be described in more detail below with reference to the accompanying drawings. In the following and above, ···. ···. 30 "energy" and "power" in the context of this application mean essentially the same thing, i.e. "energy" or "energy". the "power" which the sensor must have at the time of the imaging event to enable imaging.

• · • • · ·

35 BRIEF DESCRIPTION OF THE FIGURES

«« · * * ♦ ··· /. Figures 1, 2a and 2b show a typical intraoral X-ray device.

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Figure 3 shows components of a sensor and its base station suitable for use in the imaging system of the invention.

5

Figures 4a and 4b show one arrangement according to the invention for implementing transport links.

Figures 5 and 6 illustrate embodiments 10 of the invention for methods of delivering drive energy to an intraoral sensor in connection with an imaging event.

DETAILED DESCRIPTION OF THE INVENTION

Figures 1, 2a and 2b illustrate a typical intraoral X-ray device (1) comprising a control panel (2), an articulated arm structure (3) and an X-ray source (4). Fig. 2b further illustrates an elongated collimator (4 ') which can be attached to the housing of an x-ray source (4) to further define the beam and thereby minimize the radiation dose received by the patient. The multi-part arm-to-joint structures (3) of the intra-x-ray apparatus provide ample degrees of freedom to position the x-ray source (4) as desired.

Fig. 3 shows a sensor (30) and a base station (40) suitable for use in the imaging system according to the invention. components. Figures 4a and 4b, by contrast, illustrate by way of example the method used in the invention. the transfer links (33, 43; 36, 46) shown in section 3 may be arranged in the intraoral X-ray apparatus (1) of Figures 1, 2a and 2b.

* · • · · ·

The sensor (30) of Fig. 3 includes an FPGA or ASIC circuit (31) controlling its various functions and a CMOS detector (32).

Energy can be supplied to the sensor (30) via a wireless transmission • (33, 43) which, in the embodiment of Figure 3, comprises a coil (34) on the side of the sensor (30): * · An inductive link receiver (33). The coil (34) of the inductive transducer (33) may be arranged, for example, to be rectangular in shape to substantially conform to the circumferential shape of the sensor (30) and to be located substantially near at least a portion of the edges of the sensor (30). It is advantageous for the coil (34) 5 to be arranged in connection with the sensor shell such that the winding will not limit the active detector surface available on the sensor. The receiver (33) provided with the sensor may also be, for example, an RF receiver or other similar energy-receiving, electrically non-chargeable 10 component.

The power supply circuit (35) included in the sensor (30) may itself include, for example, a rechargeable capacitor or, for example, a battery, but the sensor (30) may also be implemented such that it does not contain any component storing energy in advance to enable its use without "on-line power supply" during the imaging event via the wireless transmission link (33, 43). Thus, the transmission link receiver (33) arranged on the sensor (30) is either a primary power supply to power the sensor electronics, whereby the energy storage capacity of the components capable of storing power in the power supply circuit (35) may be less than the individual image of the sensor electronics. the electrical power required in connection with the operation corresponds to, or • * y. ', it can operate to transmit the energy supplied to the sensor (30) • · “*. such as a capacitor serving as a primary power supply. In this case, the sensor electronics may include means for sensing the capacitance of the capacitor or other energy capable of charging the capacitor or other energy and transmitting a signal of additional power demand, e.g., when the preset threshold ti *: · and, on the other hand, means for transmitting the signal: ***: from loading or, for example, to ensure that a minimum charge level is set, such as a minimum charge for conducting 35 individual imaging events. · * The status is reached.

• · • t · • • • • • ••• 118395

The detector (32) used in the sensor (30) may be monolithic and at least some of the electronics of the sensor itself may be integrated so that, for example, the output from the detector is in a 12-bit digital format. Although such an increase in electronics will result in the loss of a portion of the active detector area, the loss can be minimized by arranging most of the components at one end of the detector (32) and the other three sides only as much of the electronics as necessary. If CMOS technology is used, the power demand of the sensor (30) is relatively low. As technology advances, it is likely that it will be possible to integrate the entire FPGA or ASIC circuit (31) into the detector (32). On the other hand, as detector technology advances, solutions other than those based on CMOS technology will probably be able to provide a sensor with the advantageous features which, in this context, are presented with the advantages of CMOS technology specifically for use in the present invention.

The image information is provided from the sensor of Figure 3 by a 2.4 GHz RF transmitter (36), either substantially real-time as the image data is detected by the detector (32) (so-called streaming mode) or substantially immediately after the image is taken. The sensor (30) may also be provided with, for example, ···. 25 RAM or FLASH memory (38) for temporary storage of the detected image data • · m ··· 'so that it can be transmitted * * **' if required. also again. The size of the memory may be adjusted to store all or part of the image information in the country, · · ····. In the latter case, the imaging system is preferably implemented such that means are provided in the base station (40) for detecting any data packets damaged during transmission, and means for rapidly transmitting information to the sensor (30). This is possible by, for example, using the energy transfer link (33, 43) for this data transfer and arranging its speed sufficiently.

More generally, the energy transfer link (33, 43) can be used to supply not only energy but also information: * ·. · To the sensor (30).

• · 10 1 1 8395

Figure 3 also shows one preferred solution for a base station (40) according to the invention. A base station in the context of this invention is primarily a functional entity, which may be arranged not only as a single physical unit, but also may have some or all of its components integrated into some other or other structure or device, such as a radiation source or imaging device. Through the inductive transmitter (43) of the tu-10 base station (40) shown in Fig. 3, the energy required to operate it can be supplied to the sensor (30) during the imaging event. As already mentioned above, the inductive link (33, 43) can also be used for communication in the direction of the sensor (30). The RF receiver (46) provided with the base station (40), in turn, receives information such as picture and status information transmitted by the sensor (30). By providing bidirectional communication to the imaging arrangement as shown in FIG. 3, one-way RF link (36, 46) on the one hand and inductive link (33, 43) on the other hand, significantly smaller and simpler one-way RF links can be used. (30) in small size.

• · · • · · «· · ♦, ···. It is possible to carry out the invention in such a way that a significant amount of * · *** is used to send control information to the sensor (30). data transfer rate from the sensor (30) is practically necessary, but also an i * «· *" e.g. an inductive link (33, 43) can be implemented to allow fast data transmission as well. for transmitting error messages during image transfer * i * tan to senso ·· ·: *** (30) in the event that one of the transmitted data packets

IM

he is damaged. After all, communication errors are not a problem when the sensor (30) has a large memory (37) such that all image information can be retransmitted if necessary. , but by arranging the data: * ·. · transfer connections so that information on the damaged data packet is transmitted to the sensor (30) quickly enough to allow the data packet still in memory (38) to be retransmitted, the use of smaller memory is sufficient.

5

The base station (40) of FIG. 3 further includes a base station power supply circuit (45), an FPGA circuit (41) for transmitting image information to the base station processor (49), and a processor-associated memory (48) for temporarily storing image information from the sensor (30). The base station (40) is further provided with Ethernet and / or USB interfaces (61, 62) for connection to, for example, an imaging device connected to a local area network, a patient management system 15 for dental practice, etc. The base station (40) may also be provided through which the operation of the radiation source (4) and the sensor (30) may be synchronized if desired, so that the imaging arrangement control system is arranged to prevent the use of the radiation source (4) unless the imaging sensor (30) is located on the power transmission link (33, 43). within the precincts of. Further, in primary electronics, means may be provided for detecting the location of the receiver (33) in the power transmission link (33, 43) within the operating range of the power transmission and the means for activating the sensor. 25 ready for imaging in response to said identification. The sensor (30) can be used, i.e., ready to receive radiation containing image information only. When the sor (30) is within the operating range of the power transmission link (33, 43), regardless of the state of charge of the component capable of charging it, the power supply may be arranged therein. Of course, the components of the base stations (40) of FIG. 3 or the like, or some of them, may also be integrated, for example, into the electronics of the radiation source (4) or physically distributed to more than one unit.

In the arrangement of the invention, the base station (40) can receive the power it needs from the bus (PowerLAN, USB) through which the image information is transmitted to the PC or to the network. However, there may be circumstances in which such an inexpensive and simple solution is not sufficient, and in view of this the base station (40) may also be provided with its own connection to the external power supply.

Figs. 4a and 4b, in particular Fig. 4a, illustrate a preferred embodiment of the invention in which the coil (44) of the inductive transmitter (43) and the RF receiver (46) and antennas (47) are physically separated from the actual base station (40) for example, an annular or rectangular adapter, or a transponder (70), for attaching to a collimator (4 ') connected thereto, connecting to the actual electronics of the base station (40) via a cable (71). Figure 4b omits, for simplicity, the RF receiver (46) shown in Figure 4a with its antennas (47), and is correspondingly supplemented with respect to Figure 4a to show how the sensor (30) would typically be positioned relative to the transponder (70) ). Thus, if in Fig. 4a a side view of the transponder (70) were also drawn with a sensor (30) and, for example, a collimator (4 ') of a radiation source (4), the sensor (30) would be located. The 25 transponders (70) on the left and the collimator (4 '), ···, would join the transponder (70) on the right.

• * * ·· «·. In the embodiment of Figures 4a and 4b, the inductor • · · · ”! the coil (44) of the transmitter (43) is thus arranged within an annular adapter • • *. ·. * 30 or transponder (70) to which the antenna (47) of the RF receiver (46) is also integrated .. * · * and its preamplifier (not shown). The adapter (70) can be attached to, for example, the end of an x-ray tube head (4) or a collimator tube (4 ') used therein. In such an arrangement · · * ... 35, the transfer links (33, 43; 36, 46) are positioned for imaging.

I I

* "always approximately the same distance as n.

• ·: t *. | 2 to 8 cm, and in the same direction relative to one another when the imaging arrangement (50) is complete, i.e., the intraoral sensor is positioned in the mouth of the patient and the X-ray source (4) is in its respective imaging position. For example, in such an embodiment of the invention, directional antennas (37, 47) can be used for transmitting the image information, which in turn contributes to the interference resistance of the communication system. It is also possible to place the antenna (47) of the RF receiver inside a collimator tube (4 ') from external sources of interference. In addition, when the communication distance between the antennas (37, 47) of the RF link (36, 46) is so short, the transmission power required by it 10 is small. In practice, the data transmission distance is then less than 15 cm, for example, in the order of 2 to 8 cm. The RF receiver (46) receiving the image information can be arranged to be insensitive and thereby render the transmission relatively immune to possible sources of interference. The short transmission distance also allows for no interference with other available sensors, without having to encode the sensors to different channels.

. With respect to energy transfer, the intraoral X-ray imaging arrangement of the invention is advantageously implemented by arranging the energy transmitter (43) on the sensor (30) to always be positioned substantially close to the sensor (30) positioned in the mouth of the patient. Such insiders ***. Examples of targets include the patient's neck, ear or. · * ·. • a holder in the headband or the like, or in the dental chair of the dental chair, or • the X-ray source itself (4).

• · • · ·

In intra-x-ray imaging, the beam is typically • collimated (delimited) to match the shape and size of the image information receiver used, and positioned * .. * · * the image information receiver in the center of the beam - which state is also illustrated in Figure 4b. The invention; *! Thus, one preferred embodiment thus comprises an arrangement in which the inductive transmitter is disposed on an x-ray source and, for example, in substantially corners of, or at least one of, substantially rectangular sensors (30) is Ϊ /. When the sensor (30) is positioned relative to the radiation source (4), or more frequently when the X-ray source is positioned relative to the sensor, the signals received from the coils change according to their position In the magnetic field produced by the inductive transmitter (43) attached to the x-ray source (4), these signals may be arranged to be transmitted, for example, via an RF link (36, 46) to signals indicating the relative position of the x-ray source (4). 10 and the desired mutual position of the radiation source (4) Of course, it is possible to get more information from more than one reel than just one. However, the receiver (33) of the inductive link (33, 43), which, for example, circulates substantially the edges of the sensor (30) alone, can also be provided with a corresponding signal, which alone can also be used to assist in positioning the sensor.

Thus, wireless data transfer for intraoral imaging can be implemented such that, for example, a sensor with a CMOS detector communicates wirelessly with a base station, to which base station or operational connection thereto is also provided with means for transmitting power ... wirelessly. When an energy-supplying transmitter • · · '· * 25 and a sensor comprising a corresponding receiver are brought into the operating range of their link, preferably one another within a close proximity, Φ such as a range of less than 50 cm, preferably less than 15 cm, such as 2-8 cm, energy can be supplied to the sensor 30 during the imaging event, whereby ··· imaging is always possible regardless of the energy charge system "··. from the charge state when imaging is initiated. In this arrangement, therefore, the · ·“ * sensor can always be used with its relative ··: '· 35 relative proximity to the energy transfer transmitter. The operating power »« · ί.,. inductively, where. ·.: the inductive transmitter is preferably located, for example, in- »♦ · S, · traoral in connection with an x-ray tube head, for example, a tubular part of its housing • ♦♦ • ♦ 15 1 1 8395 or an adapter for positioning the end of a collimator to be connected thereto. The inductive transmitter may also be integrated, for example, as part of the structure of the x-ray source.

The imaging arrangement may be implemented such that the sensor operation is not possible other than within the power link operating range, wherein, in the imaging event, the operating system of the imaging arrangement is arranged to detect when the sensor has been brought into the power link operating range. The field of inductive power transmission may be arranged at a relatively low bandwidth to minimize its potential interference with the imaging sensor. For example, the transmission frequency may be substantially less than 500 kHz, up to 15 completely different orders.

The arrangement may also be implemented such that the energy input to the sensor during the imaging event is adjustable. The arrangement can be implemented, for example, such that it is possible to keep the power supply 20 off during, for example, actual exposure, reading the image information from the detector to any memory provided on the sensor, or transmitting from the sensor to the ether. Power Link: * · *: Power can be arranged lower than the image information «.1 ·. Power absorbed by 25 transmitting link (RF) transmitters.

···. * ··. Interrupting the power transfer can help prevent power • transmission during the imaging event from interfering with it. For Sorin's action. The sensor itself may also be provided with means for adjusting its power consumption at various stages of the imaging process.

The image information detected by the detector can thus be temporarily stored in a sensor arranged in a sensor according to an embodiment of the ··· invention and transferred from the detector to · ·· * ... 35 after exposure has expired, preferably as fast as possible. This can be accomplished, for example, in an arrangement where the end of irradiation is known to be

ϊ / .ί hand or it is recognized. However, for example, just CMOS

16 1 18395 nitrogen detector signal can also be read continuously during exposure. The sensor can then also be arranged for use in a so-called. in streaming mode, i.e., so that image information is continuously transmitted from the sensor during exposure 5. For example, a signal stored in the PC's memory can then later be programmed to detect the beginning and end of exposure. When the image information is transmitted in real time at the same rate as it is read at, for example, every 300 ms, knowing the maximum exposure time is not necessary from the viewpoint of image acquisition, since any information that may cause overexposure can simply be ignored.

All in all, according to the invention, therefore, the sensor can be supplied with energy at the time of the imaging event, so that it is always available for imaging, irrespective of the charge state of the component capable of absorbing energy when the imaging starts.

20

An Inductive Transmitter, such as an intraoral X-ray source in the embodiment of Figure 4b, may be provided with a Attention Light or other signal which, after imaging, ···, indicates that the transmission of image information is complete. Of course, with the use of 25 • sensors with memory, data transfer • «IX can of course also be interrupted, do not do so later than • • *» ··] and / or send information more often * * than if the data transfer is one way or another. unfortunate .. *! * resolved. For later data transmission, for example, a rack can be provided in connection with the x-ray tube, where the sensor can be placed after imaging to allow communication with the base station arranged in the x-ray tube. even after the actual imaging. Information * is preferably transmitted from a sensor using high frequency • 35 radio transmitters and, for example, transmission power of the order of less than 1 mW • · · • · * ... * to minimize the effect of transmission on the CMOS detector and sensor · '·, * digital electronics.

• · • · • i «• · * • · 118395

Figures 5 and 6 show two examples of how the invention can be practically applied to intraoral X-ray imaging. Figure 5 illustrates the use of the invention in a manner in which the mutual operation of the radiation source and the energy transfer link is synchronized. According to this embodiment, in the first step, when the X-ray source is turned on, the arrangement enters the STAND BY state. The preparation stage for imaging may include e.g. at least a preliminary positioning of the radiation source, the object to be imaged and the sensor for imaging 10. Then, when the actual imaging is initiated by the irradiation start signal from the radiation source start switch, the system first activates the energy transfer link transmitter of the invention and checks whether the link operation is within the range of a sensor unit that the system 15 recognizes. (Because the sensors are all individual and require sensor-specific calibration data to be used, only sensors whose correction (calibration) file is stored in a database of the imaging arrangement can be used for imaging to produce a "real" image of just 20 of the image information A unique serial number can also be used to prevent unauthorized access to the sensor and to prevent it from being stolen by using a user-specific access code.) In practice, sensor identification • · ·, · * · 25 occurs by locating the power transfer link. within the operating range, the sensor transmits • · ** ·. via a data link, in response to its activation of a signal containing its unique identifier. If the system does not store that identifier in the system, then if ··% · ... · 30 an attempt is made to use a sensor that is not recognized by the databases used by the imaging system, or if, for example, and the receiver's distance is greater than the link's range, or if the sensing power of the component capable of charging the sensor is too low, or if the system detects some other error. in the image order, the irradiation does not start and the system gives an error signal, for example an audible signal, and • ·: * ·. · indicates the cause of the error. The error signal may also be caused by • · 1Ί 8395 18 for example, inaccurate positioning of the sensor relative to the beam of radiation emitted by the radiation source *

Then, the conditions for successful imaging exist, for example, the EXPOSURE Attention light in the base station of the arrangement lights up, and if the arrangement does not include imaging exposure automation, irradiation for a preset time begins. After exposure, the EXPOSURE Attention light turns off. After exposure, the arrangement may go to 10 more BUSY modes, the duration of which may depend e.g. how the sensor information is transferred from the sensor to the sensor, for example, whether there is memory for transferring all or part of it after exposure, whether feedback is provided to transmit to the sensor information that may be damaged during transmission, etc. also implements that the information detected by the detector is first stored in the memory of the detector, after taking the image, its sor is transferred to, for example, a holder arranged in connection with the base station, i.e., in position where it is in power transmission link range and image information is transferred from the sensor. Ku-; 1 · *: After transferring only the information, the daytime running lights turn off, energy Φ .2. 25 transfer links are deactivated and the system returns to STAND BY ti- ···. * · *. temperature.

Figure 6 shows an example of an embodiment in which the energy transfer link and the radiation source operate independently of each other. In this solution, the energy transfer link

the kiosk is communicating with a PC, for example, and while on STAND

♦ ..li * BY mode, the power link transmitter sends periodic short pulses to the ether ··· ϊ, φ4φ, whereby the mode of operation of the transmitter in response to the signal that the sensor is found within the operating range of the · ··· switches from said periodic pulse. from the state to the actual READY state, and the sensor ack, * ··, becomes ready for imaging. For the sake of simplicity, the diagram in Fig. 6 omits 2: \ j to attempt to use something other than the sensor entity known in the system. If no actual exposure is made to the system, for example, within a predetermined period of time, when the system enters the READY state, i.e. if, for example, no signal is received from the sensor to start the irradiation, the system returns to the STAND BY mode described above. Such This may be the case, for example, if the positioning of the sensor and radiation source 10 takes an exceptionally long time to photograph.

Detecting the onset of irradiation causes the system to change state to the EXPOSURE mode, during which the information detected by the detector 15 is integrated, for example, at a predetermined time or until it is detected that the irradiation has ceased. If the arrangement is implemented such that the information detected by the detector is read out from the detector at short intervals throughout the exposure, the detection of the end of irradiation 20 may be based, for example, on the observation of a sudden drop in the detected signal level. The transmission of image information from the sensor may also be accomplished, for example, in one of the ways described above in connection with the description of FIG.

«· 1 • · · · · ·

In this context, the invention has been specifically described in its first application. ice, preferably for use in intraoral X-ray imaging. Operating power Φ ·. In principle, 30 may be provided to the sensor by other wireless technology than the inductive form of the above embodiments, and in principle, I will use only one link to transfer energy (and information) ..!: 1 to the sensor on the other hand. · «· 5, ..: 35 tone sensor. However, the above embodiments; An arrangement whereby the sensor is supplied with energy • 1 · * ... inductively and image information transmitted at radio frequencies correspondingly provides excellent intra- • a · · · ♦ · ♦ • f 20 118395 Energy transfer / bidirectional data transfer capable of oral imaging. In this case, it is also possible to construct the imaging arrangement such that the magnetic field generated by the power transmission link can also be utilized in positioning the sensor 5 relative to the X-ray source, as described above.

Thus, according to a preferred embodiment of the invention, the sensor data transmission is bidirectional and implemented, for example, by transmitting image and status data from the sensor at high speed (such as at least 10 Mbit / s) over a substantially high frequency, e.g. 2.4 GHz RF transmission link inductively, whereby the inductive link can also be used for slower communication (such as less than 9600 kbit / s) in the direction of the sensor, such as transmitting sensor control signals.

The sensor of the invention can be implemented without large, wearable or aging or replaceable components, such as batteries, for a long life. In fact, almost the only possibility of such a sensor being broken is mechanical damage from excessive mechanical stress, such as physical impact from the sensor falling to the floor or other similar damage ... 25. The risk of falling to the floor can be prevented by, for example, the arrangement of a safety lanyard and a small bracket or similar fastener that can be secured to the back of the sensor. For example, if used with a thin Kevlar * · 1 "fiber or nylon line, it can be • j1 30 cold-sterilized in combination with a sensor, or disposable cords can be used. at all.

Thus, the invention and its preferred embodiments of the present invention provide novel ways to implement a wireless intraoral sensor. For example, · 1: high frequency and unidirectional The use of the RF link for data transmission allows for a simpler and smaller sensor structure that is also considerably simpler to control, and also provides low power consumption over the data link, 5 The use of a short transmission distance and a high frequency communication link allows the implementation of the invention without the need for sophisticated, specific application-specific arrangements using previously known proven solutions. The components of the RF link can be implemented either as a discrete section or as an integrated circuit, the use of which does not interfere with the reverse link inductor included in the arrangement when the links use substantially different frequency bands. The image information can be transferred in real time if desired.

According to the invention, the imaging sensor can be implemented in a small size when the energy required to operate the sensor can be supplied to the sensor in part or in full at the time of the imaging event. Thus, if a component capable of storing energy is to be provided in the sensor, it can, however, be implemented in a small size. The sensor does not need to be preloaded and can be implemented without ... 25 batteries or other replaceable or maintenance-requiring components, allowing it to be • hermetically enclosed and galvanically isolated, which allows it- • · * · ..1 Sori cold sterilization between imaging of different patients.

It will be apparent to one of ordinary skill in the art that the present invention is practicable within the scope defined by the following claims, other than the above embodiments, e.g. de- • · · ·. · 1 ·. • · * 35 new advancements in tector technology.

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Claims (53)

1. Intraoral X-ray imaging arrangement to which a control system belongs, a radiation source (4) soin is arranged in connection with, for example, a articulated shaft structure (3), an electric receiver of image information such as, for example, a sensor (30) based on CMOS technology, and a wireless transmission link (33, 43; 36, 46) for transmitting at least the image information detected by the sensor (30) to the base station (40) of the sensor, to an image processing machine or to a corresponding other apparatus whose transmission link (33) , 43; 36, 46) transmitters and receivers are arranged on one side in connection with the sensor (30) and on the other side in at least functional connection with said base station (40), characterized in that the arrangement also includes, or the transmission link (33, 43; 36, 46) is arranged to function also as a wireless power transmission link (33, 43), which is arranged to be used for the conveyance. rgi to the sensor (30) in the context of an imaging process. • »· V1 · 2. Imaging arrangement according to Claim 1, characterized by: [[1] wherein the receiver (33) of said wireless power transmission link (33, 43) is arranged to be a ··· part of the sensor electronics . 3. The imaging arrangement according to claim 1 or 2, characterized in that said receiver of the sensor electronics belonging to the wireless power transmission link (33, 43) • · • 2 30 (33) is the tili the sensor electronics belonging to the power source circuit's primary power source or a component of energy transfer: V: tili a component that possibly belongs to the sensor electronics and is capable of storing energy. ··· # 2 * · ♦ Imaging arrangement according to any one of claims 1-3, 3 * .1 characterized in that the power transmission link (33, 43. receiver) is an inductive (33) or RF receiver (46) 36 Λ _ _ _ 118395 or corresponding wireless electromagnetic energy receiving, electrically non-storable component. Imaging arrangement according to any one of claims 1-4, characterized in that means are heard to transmit energy to the sensor (30) during the actual imaging process. Imaging arrangement according to any one of claims 1-5, 10, characterized in that the total energy storage capacity of the possibly-hearing component (s) of the sensor electronics, or the components capable of storing energy, is less than the energy required by the sensor (30). associated with an individual imaging process. 15 Imaging arrangement according to any of claims 1-6, characterized in that the operating range of said power transmission link (33, 43) is arranged to be short, such as below 50 cm, advantageously below 15 cm, such as 2-8 cm. 20 Imaging arrangement according to any one of claims 1-7, characterized in that said transmitter (33, 43) of the transmitter (33, 43) is positioned or arranged on the plate ··· ***. . detectable in a location or in a position in which, when the M »object to be imaged and said sensor (30) is * positioned at its imaging positions according to the imaging arrangement (50), the sensor (30) is positioned in the transmission - ** (*, * 43) operating range. 9. Imaging arrangement according to claim 8, characterized in that the transmitters of the power transmission link (33, 43) have been arranged positionable on the radiation source (4) or in. ···. its essential proximity arranged base station (40), or, for example, to a base station (40) which has been arranged to be attached · * · * * V .: 35 to a patient or patient's headrest. «« · • * ··· Imaging arrangement according to any of claims 1-9, characterized in that it belongs to means for transmitting a signal from the sensor (30) in response to the transmitter (33, 43) and the transmitter of the power transmission link (33, 43). 43) is in the operating range of the PTO (33,43). Imaging arrangement according to claim 10, characterized in that it belongs to means for synchronizing the function of said power transmission link (33, 43) and the radiation source (4) in such a way that the radiation cannot be started on the imaging arrangement (50). control system does not have information about the power transmission link (33, 43) arranged in the sensor and its receiver (33) lying in the operating area of the power transmission link (33, 43). Imaging arrangement according to any one of claims 10, 15, characterized in that it belongs to means for synchronizing the function of said power transmission link (33, 43) and the radiation source (4) in such a way that the radiation cannot be started before a signal from the sensor has been received that its storage position is sufficient according to a predetermined limit value, for example, considering the applied power transfer rate sufficient to carry out at least one imaging process. ··· · • · «··. ***. Imaging arrangement according to any of claims 1- ··· 12, characterized in that tili has been arranged for this means for controlling the power transmitted to the sensor (30). and / or used by the sensor (30) during the imaging process. * · ··· Imaging arrangement according to any of claims 1-13, characterized in that it belongs to means for two-way • * · * ... · data transfer between the image information receiver and the imaging arrangement (50) control system, which information • *. ···, includes at least control commands and image information • · [· * detected by the image information receiver. Imaging arrangement according to any one of claims 1-14, characterized in that said power transmission link (33, 43) is arranged to convey during the imaging process. both the energy needed by the sensor (30) and the control signals of the sensor (30). The imaging arrangement according to claim 15, characterized in that said power transmission link is an inductive link (33, 43). The imaging arrangement according to claim 16, characterized in that the receiver (33) of said inductive link (33, 43) comprises a coil (34) which substantially follows the shape of the circuit of the sensor (30), in close proximity to the input terminal. stone part of the sensor edges. The imaging arrangement according to claim 16 or 17, characterized in that, in the said receiver of image information, one or more relatively small coils have been arranged in such a manner that they are substantially adjacent to at least one corner of, for example, substantially rectangular receivers of image information, the coil or coils having been arranged to convey information of the position of said receiver relative to the transmitter (43) of said inductive link (33) in the magnetic field which it forms. ··· • 1 • · ···. · 2 ·. The imaging arrangement according to any of claims 1-18, characterized in that said wireless transmission link (36, 46) for transmitting at least the image information detected by the sensor (30) is an RF link. • · • · 20. Imaging arrangement according to claim 19, characterized in that said RF link (36, 46) is one-way and / or high-frequency and / or directional used. antennas. • 1 · · * 11 21. Wireless electric receiver of image information, especially • m 35 for use in connection with intraoral X-ray imaging, which 2 Ml 3 Σ,. Ϊ includes a sensor housing and sensor electronics arranged within it, to which sensor electronics belong to one detector (32) based, for example, on CMOS technology, a transmitter for transmitting to the ether at least image information detected by said detector (32) and a power source circuit (35), characterized in that to the power source circuit further belongs, or the said transmitter is arranged to function also as a receiver (33) for the wireless power transmission link (33, 43), to which receiver (33) belongs and / or to functional connection with which means for arranging means have been arranged. receiving and transmitting energy in the context of the imaging process. 10 22. The image information receiver according to claim 21, characterized in that it belongs to means for transmitting a signal from the sensor (30) in response thereto, that it has been brought into the functional area of said power transmission link (33, 43), which signal also may include identification information specifying the sensor in question; Receiver of image information according to claim 21 or 22, characterized in that the receiver (33) of said power transmission link (33, 43) is an inductive or an RF receiver or a corresponding, electrically non-storage · * · * 'Bare component which wirelessly receives electromagnetic energy. • ·· • m • · ··· ··· Receiver of image information according to any of the claims *: **: 21-23, characterized in that the energy storage capacity of the said possibly connected to the sensor power source circuit ···· * · *. (35) the hearing-storable component or components are ··· less than the energy needed by the sensor (30) in connection with a single imaging process. The receiver of image information according to any of the claims: 21-24, characterized in that the said sensor: ***: electronics has been arranged to identify the ligand. of the power transmission link (33, 43) receiving (33) in the operating range of the power transmission link (33, 43) and means for activating the sensor ready for imaging in response to said identification. 40 1 1 8395 Receiver of image information according to any of claims 21-25, characterized in that the said sensor electronics belong to means for identifying the storage state of the capacitor or of another component capable of storing energy belonging to the sensor electronics, and to transmit a signal of need for additional energy when said storage condition is below a predetermined limit value. Receiver of image information according to any of claims 21-26, characterized in that the said sensor electronics belong to means for identifying the storage state of the capacitor or of another component capable of storing energy belonging to the sensor electronics, and to transmit a signal in that the storage state of the capacitor or of another component capable of storing energy is consistent with a predetermined minimum storage state. Receiver of image information according to any of claims 20 to 21, characterized in that means have been arranged to the sensor to control the force it receives and / or uses in the context of the imaging process. ··· • · · · ··· Receiver of image information according to any one of claims *: ··· 22-28, characterized in that the receiver (33) of said power transmission link (33, 43) is an inductive receiver »·· (33). 30. Receiver of image information according to claim 29, characterized in that said power transmission link's receiver (33, 43) comprises a coil. (34) which essentially follows the shape of the circuit of the sensor (30), substantially · 3; of at least part of the edges of the sensor (30). • · · · 2 • · · 3 31. Receiver of image information according to claim 30, characterized in that means for functionally connected to said coil (34) have been arranged means for measuring and transmitting information of the magnetic field's strength as the power transmitting transmitter (1) 8395 sensor (30). (43) of the inductive link (33, 43) has formed. Receiver of image information according to any of claims 22-31, characterized in that it is essentially a rectangular shaped sensor (30), substantially in the vicinity of the at least one corner of which a rectangle has been arranged a coil, in the functional context of which means have been arranged to measure and transmit information about the strength of the magnetic field 10 formed by the transmitter (43) of the inductive link (33, 43) of the transmitting power (inductive) link (33). Receiver of image information according to any one of claims 21 to 32, characterized in that the sensor electronics 15 belong to means for receiving control information which may be conveyed in connection with said wireless power transmission. Receiver of image information according to any one of claims 22-33, characterized in that its component for transmitting image information is an RF transmitter (36), in particular a V: high frequency, such as a one-way 2.4 GHz RF transmitter ··· (36) in possession of a directed antenna. The receiver of image information according to any of claims 22 to 34, characterized in that the sensor electronics ····, ···. belongs to means for storing at least a portion of the image information detected by the detector (32) in a memory .. (38, 48) belonging to the sensor electronics, as well as examples in RAM or The FLASH memory, at the same time as image information is still detected or substantially immediately after receiving: V: capture of image information has been completed. • · · • ♦ • · «··, *. 36. Receiver of image information according to claim 35, characterized in that the sensor electronics belong to • · * ··· * means for transmitting again the said information information to the memory (38, 48) or part of it. this in response to a control signal, such as wireless, such as via said receiver (33) of the link (33, 43) used for the power transmission, has been received by the sensor (30). 37. Base station for intraoral X-ray sensor, which comprises 5 components in functionally connected to each other forming the electronics arrangement of the base station (40), to which components belong to a component which traditionally receives at least image information from a sensor (30) used in X-ray imaging, characterized by that the base station 10 (40) further belongs to the means, or said image information receiving component has been arranged to also function as a component which traditionally transmits to the sensor (30) energy needed in the imaging process in response to a from said sensor (30) receives a signal during the mapping process, according to which the sensor (30) is located within the operating range of said link (33, 43). 38. Base station according to claim 37, characterized in that said signal is arranged to be supplied from sensor 20 (30) in response to a signal sent from base station (40) and received by sensor (30). · «· • · · • · f Ml 39. Base station according to claim 38, characterized in that: means for controlling the base station (40) are arranged for checking if said signal contains an identifiable identification information specifying the sensor (30). ). • t · · • M 40. Base station according to any of claims 37-39, characterized in that the electronics of the base station (40) are arranged in functional connection with the radiation source (4) used in the imaging of such a way that radiation use (4) use (4) is prevented if the control of the arrangement is controlled. system does not contain information that said sensor II · (30) used in the imaging is located within said operating range of the link (33, 43). i ·· • I • f • Il A base station according to any of claims 37-40, characterized in that the base station (40) belongs to means 43 to 8395 for transmitting to the sensor (30) also the control information of the sensor (30) via said link (33, 43). ) transmitter (43). 42. Base station according to any of claims 37-41, characterized in that the component transmitting energy to the sensor (30) is an inductive transmitter (43). 43. Base station according to any of claims 37-42, characterized in that at least the said component of the base station (40) receiving information is a receiver (46) of a unidirectional and / or high frequency RF link (36, 46). ). 44. Base station according to any one of claims 37-43, characterized in that the base station (40), or at least the aforementioned part of this functionally associated energy transmitting component, has been arranged to be attached or it has been integrated into a certain kind of support means or to a somewhat peculiar imaging arrangement (50) associated with construction 20 which, in connection with the imaging process, when the sensor is positioned in its imaging position, positions itself in a ··· V: substantial proximity, such as below 50 cm, advantageously below 15 ··· ϊ. , .ϊ cm, such as at a distance of 2-8 cm from the sensor (30) used in imaging, which construction is, for example, a ····· 25 head or neck band or equivalent, the patient chair head support, x-ray source ( 4) used in the image, ··· «. ···, or an element that can be attached to any of the above. • · * ·· 45. Base station according to any of claims 37-44, characterized in that the transmitters (43) and / or receivers (46) for the image information of the energy-transmitting link (Y) comprise a coil (34). ), and / or the corresponding antenna (71), at least one of which is arranged to be attached. at the orifice of the X-ray source (4), or at the orifice of the connecting collimator tube (4 '), or in the proximal divisible proximity of such an orifice, such as into said orifice. 44 1 1 8395 46. Base station according to claim 45, characterized in that the transmitter (43) of said energy transmitting link comprises a coil (34) having substantially the same shape and size as the cap of said X-ray source (34) or collimator tube (4). ') the orifice is connected thereto, or forms part of an adapter (70) which is integrated, fixed or arranged attachable to said orifice or in its essential vicinity. 47. Base station according to any of claims 37-46, characterized in that the electronics required for use of said transmitter energy transmitter (43) and / or said image information receiver (46) are integrated as part of the X-ray source ( 4) electronics. 15 48. Base station according to any of claims 37-47, characterized in that means are provided for the base station (40) to identify the possibly received data packets containing defective image information and means for transmitting information about this to the sensor (30). . • MV: 49. Method of use an X-ray imaging sensor, which sensor comprises a sensor housing and sensor electronics arranged into it and in which method an imaging arrangement is used, in which the energy for using the sensor is taken from an energy source arranged in conjunction with the sensor, • • t. ···. characterized in that, at least for its part, a receiver of a ♦ wireless transmission link is used as the energy source of the said sensor by conveying energy to the sensor which is needed for its use via the said wireless transmission system. · * Link in connection with the mapping process. • · • · · • · «• · • ***; Method according to claim 49, characterized in that the operation of the sensor is controlled so that it is activated only when it is within the operating range of the said wireless transmission link. 118395 51. A method according to claim 49 or 50, characterized in that energy transfer to the sensor and / or the sensor's power consumption is controlled during the imaging process. 52. A method according to any of claims 49-51, characterized in that the transmission of the energy to the sensor is started as a response to a signal, according to which the storage position of the capacitor or of any other component capable of storing energy belonging to said sensor electronics is located. settles below a predetermined limit value for said storage position. 53. A method according to any of claims 49-52, characterized in that energy transmission to the sensor is terminated in response to a signal according to which the storage position of the capacitor or of any other component capable of storing energy belonging to said sensor electronics has been achieved. a predetermined limit value. 54. A method according to any of claims 49-53, characterized in that during the actual exposure associated with the image process, during the imaging process the image information is read • M from the detector to a memory possibly arranged in the sensor • t · ' · T and / or while it is sent from the sensor to the ether, the sensor • · · '*: ··; 25, energy is transmitted via the said transmission link only slightly ··· or not at all. ···· ··· • · * · • M 55. A method according to any of claims 49-54, characterized in that the sensor is arranged to be activated in connection with the imaging process as a response to a signal, which indicates that the transmitter of said transmission link and * ,? t! receivers are set in the transmission link's operating range, which signal is acquired so that before the start of the mapping process, the transmitter of the said link is stalled in STAND BY, whereby it begins to transmit in forest • · *** ' signal pulses to the ether to reconnect if a possible imaging arrangement sensor used in the imaging process is located within the transmission link's operating range, and is transmitted in response to said pulse from such a sensor its identification information containing signal, in response to this identification signal, the transmission link transmitter and receiver are located in the transmission link's operating range, the transmission link's status changes to readiness mode (READY) and the sensor is activated as imaging ready. 56. A method according to any of claims 49-55, characterized in that the operating range of said transmission link is arranged to be small, such as below 50 cm, advantageously below 15 cm, such as 2-8 cm. 57. A method according to any of claims 49-56, characterized in that, as said transfer link, an inductive link is used. 58. A method according to claim 57, characterized in that the sensor is positioned relative to the beam cone used for the imaging by using the information obtained in a magnetic field produced by the inductive V transmitter from the coil of the inductive receiver arranged to the transmitter. ·· «sorn and / or from one or more other tili sensors for this purpose coil arranged. ·: ··: 25 • i. 59. A method according to any of claims 49-58, characterized by ···· ················································································ weather Assist Latest Online Login Guide Online Consolidation Guide, In That The Transmission Link Is Also Used For Information Transmission, As Sensor Control Information. 47 1 1 8395 61. A method for transmitting information to and from an intraoral X-ray sensor, in which method at least a portion of the information transmitted from the sensor is image information and in which at least part of the information is transmitted wirelessly, characterized in that at least a portion of the information is transmitted tili the intraoral sensor is conveyed through such a wireless link, through which the sensor can also convey energy needed for the use of the sensor. 10 62. A method for transmitting information according to claim 61, characterized in that the sensor is conveyed energy substantially in the context of the imaging process, i.e. during the mapping process itself. 15 63. A method for transmitting information according to claim 61 or 62, characterized in that the information required for the sensor is at least part of some information associated with controlling the operation of the sensor. 20 64. Method for transmitting information according to claim 63, characterized in that the control information conveyed to the sensor comprises a command information for transmitting at least some of the image information detected by the sensor. ··· ····; 25 .j. 65. A method for transmitting information according to any of the following claims, 61-64, characterized in that image information is conveyed from the sensor during the imaging process .. related exposure or substantially immediately after exposure. - L. "30 a. • · • · ··» f: V: 66. Method for transmitting information according to any of the following: Exam requirements 61-65, characterized therein, that energy and · ". *. Information is conveyed to the sensor via an inductive link. 67. Method of transmitting information according to any of claims 61-66, characterized in that image information is transmitted using an RF link, such as a single-directional, advantageously a high-frequency RF link, in which directional antennas are used. * ·· * · · • · · ··· «m 9 · ··« 999 • · • · · ·· * 9 9 9 999 9 9999 999 9 9 9 9 999 99 9 9 9 99 9 999 9 9 9 9 999 9 9 9 9 9 9 9 9 9 9 9 999 9 9 9 9 999 9 9 9 9 9 9 9 9 9 9 9 999 9 9 9 9 999