[0001] The present disclosure relates to a new method for providing configuration information
of a hearing aid, a hearing aid adapted to perform the method, and a system for fitting
a hearing aid utilizing the configuration information.
[0002] BTE (behind-the-ear) hearings aids are well-known in the art. A BTE hearing aid has
a BTE housing that is shaped to be worn behind the pinna of a user. The BTE housing
accommodates components for hearing loss compensation. A sound signal transmission
member, i.e. a sound tube or an electrical conductor, transmits a signal representing
the hearing loss compensated sound from the BTE housing into the ear canal of the
user.
[0003] The output transducer may be a receiver positioned in an ear canal of the user of
the hearing aid, a so-called
Receiver-
In-the-
Ear. In the following, a hearing aid with a
Receiver-
In-the-
Ear is denoted a RIE hearing aid.
[0004] In a RIE hearing aid, the sound signal transmission member comprises electrical conductors
for propagation of hearing loss compensated audio sound signals from the hearing aid
circuitry in the BTE hearing aid housing through the conductors to the receiver positioned
in the ear canal of the user for emission of sound towards the eardrum of the user.
[0005] In order to position the receiver securely and comfortably in the ear canal of the
user, an in-the-ear housing, earpiece, shell, or earmould may be provided for insertion
into the ear canal of the user.
[0006] In the following, the terms in-the-ear housing, earpiece, shell, and earmould are
used interchangeably.
[0007] Typically, hearing aid manufacturers provide a number of different earpieces with
receivers having different output power specifications, e.g. 5 different output power
levels.
[0008] Typically, earpieces are also provided having sound signal transmission members of
different lengths, e.g. 8 different lengths, to suit the individual anatomy of the
intended user.
[0009] Thus, e.g., 8 * 5 = 40 different earpieces may be used together with a specific BTE-housing.
[0010] Additionally, in order to fit the user's ear and secure the sound signal transmission
member and other components in their intended position in the ear canal and prevent
the earpiece from falling out of the ear, e.g., when the user moves the jaw, the earpiece,
shell, or earmould may be individually custom manufactured or may be manufactured
in a number of standard sizes, which further multiplies the number of earpieces that
may be used together with a specific BTE-housing.
[0011] The earpiece may further accommodate one or more microphones, e.g. a microphone used
for suppressing the occlusion effect and/or one or more microphones for recording
directional cues further multiplying the number of earpieces that may be used together
with a specific BTE-housing.
[0012] This results in a very large variety of earpieces that can be used together with
a specific BTE-housing.
[0013] Thus, a large variety of hearing aids may be provided by provision of different combinations
of a smaller number of different subassemblies. Therefore, there is a need for automatic
detection of the actual configuration of each hearing aid.
[0014] Thus, a new hearing aid is provided with
a first housing accommodating first circuitry,
a second housing accommodating second circuitry, and
a connector configured for interconnection of the first circuitry with the second
circuitry, wherein the connector comprises
a line for transmission of a first signal between the first circuitry and the second
circuitry, wherein
the second circuitry includes a transmitter configured for transmission of a second
signal with configuration information to the first circuitry utilizing the line, and
wherein the first signal does not contain the configuration information.
[0015] The new hearing aid may be configured for adjusting its operation in accordance with
the configuration information.
[0016] The second circuitry with the transmitter may be configured for transmission of the
second signal with configuration information to the first circuitry at power up of
the hearing aid; and/or upon the hearing aid receiving a user request for transmission
of the second signal, from a user interface of the hearing aid; and/or upon the hearing
aid receiving a request for transmission of the second signal, from external equipment,
such as a fitting instrument.
[0017] A new method is also provided of identifying a component, or a combination of components,
that is connected to a circuit with a connector, comprising transmitting configuration
information on the identity of the component, or combination of components, on a line
coupled with the connector and provided for transmission of other information than
the configuration information.
[0018] Thus, a new method is provided of configuring a hearing aid having a connector that
interconnects first circuitry of the hearing aid with second circuitry of the hearing
aid, the connector having a line configured to transmit a first signal between the
first circuitry and the second circuitry, the method comprising transmitting a second
signal containing configuration information relating to the second circuitry to the
first circuitry using the line, wherein the first signal does not contain the configuration
information.
[0019] A new fitting instrument for a hearing aid is also provided, which is configured
for reception of the configuration information.
[0020] The new fitting instrument may be configured for fitting the hearing aid in accordance
with the configuration information.
[0021] The new fitting instrument may be configured for displaying a message in response
to the configuration information.
[0022] The new fitting instrument may be a dedicated instrument, or a PC with suitable fitting
software, a hand-held device, e.g. a tablet computer, a smartphone, etc., with suitable
apps, etc.
[0023] With automatic identification of a component, or a combination of components, e.g.
a receiver in an earpiece, maladjustment of the hearing aid in question is avoided.
[0024] For example, faster and safer initial fitting can be performed by the dispenser due
to the automatic identification of component(s), e.g. a receiver type, during the
initial fitting of the hearing aid to the intended user, e.g. inadvertently exchanged
left and right in-the-ear housings may be automatically detected. The dispenser is
also relieved of the task of manually entering configuration information during fitting,
and incorrect gain calibrations and output levels due to erroneously manually entered
component information are avoided.
[0025] Further, malfunctioning of the hearing aid due to inadvertent undesired combination
of components, such as inadvertent interconnection of a wrong in-the-ear housing to
a BTE-housing, is avoided. For example, a boot process of the hearing aid may be stopped
when an undesired combination of components is detected, and/or certain functions
of the hearing aid may only be enabled if a combination of components suitable for
performing the functions is detected.
[0026] Yet further, correct replacement part numbers may be easily identified for the hearing
aid in question.
[0027] Still further, a user of the hearing may be warned of an incorrect combination of
components, such as when left ear and right ear components are unintentionally exchanged,
e.g. when an in-the-ear housing intended for the right ear is inadvertently connected
to the BTE-housing fitted for the left ear. A user may also be warned if wrong replacement
parts are inadvertently delivered to the user and used with the hearing aid, whereby
the user may be saved annoyance and possible extra visits to the dispenser's office.
[0028] The automatic identification is provided without increasing the number of conductors
interconnecting the first and second circuitry, since the line used for transmission
of the configuration information is already present for another purpose. In this way,
existing hearing aid parts may be configured to perform the new method without hardware
modification, such as modification of the connector. Also, complexity and cost of
the connector is kept at a minimum.
[0029] The first signal may be an audio signal representing sound, for example an audio
signal transmitted to a receiver for emission of the sound towards an eardrum of the
user.
[0030] The second circuitry may include a power supply. The power supply may be energized
through the line. For example, the power supply may be charged by transmitting a high
frequency signal f > 20 kHz on the line The power supply may be a capacitor.
[0031] The second circuitry may include a receiver. The line may be an input line of the
receiver.
[0032] The transmitter may be configured for transmitting a signal with at least one varying
signal parameter, such as amplitude, frequency, phase, pulse width, etc.
[0033] The transmitter may be configured for modulation of the line, such as by amplitude
modulation, frequency modulation, phase modulation, etc.
[0034] The transmitter may be configured for digital modulation of the line, such as by
phase-shift keying, frequency-shift keying, amplitude-shift keying, quadrature amplitude
modulation, etc.
[0035] The configuration information may include information identifying the particular
arrangement of parts or components interconnected with the first and/or second circuitry.
[0036] In particular, the configuration information may include an identifier of a component,
and/or a combination of components, of the second circuitry.
[0037] The type and fitting parameters of the hearing aid may be strongly dependent on the
component, or combination of components, of the second circuitry.
[0038] Therefore, it is important to provide the correct combination of first and second
circuitry of the hearing aid and fitting parameters of the hearing aid, for a specific
user.
[0039] An incorrect combination may result in a significant maladjustment of the hearing
aid.
[0040] The transmitter may be configured for transmitting the configuration information
by short-circuiting the line. The short-circuiting may cause corresponding voltage
drops of the battery supply voltage that may be detected and decoded by the first
circuitry, for example by a signal processor, e.g. a signal processor configured for
performing hearing loss compensation, of the first circuitry, whereby the one component,
or the combination of components, of the second circuitry is identified in the first
circuitry.
[0041] The first housing may be a behind-the-ear housing and the second housing may be an
earpiece.
[0042] The second circuitry may have a microcontroller programmed to short-circuit the line
in accordance with an encoded time sequence for identification of the one component,
or the combination of components, of the second circuitry.
[0043] RIE hearing aids may be provided with a connector for easy connection and disconnection
of the second circuitry of second housing, such as an earpiece, to the first circuitry
of the first housing, such as a BTE housing. For example, in this way, various types
of receivers in earpieces may easily be connected to a BTE housing thereby providing
different hearing aids with different receivers.
[0044] The new fitting instrument may automatically respond to received configuration information,
e.g., by selecting hearing aid parameters in accordance with the received configuration
information, e.g. a specific model of receiver identified. In this way, the receiver,
the hearing aid and the hearing aid fitting parameters are combined correctly.
[0045] The operator of the new fitting instrument may take appropriate action in response
to a display of the configuration information, e.g., by adjusting hearing aid parameters
in accordance with the configuration information, e.g. a specific model of receiver
identified. In this way, the receiver, the hearing aid and the hearing aid fitting
parameters are combined correctly.
[0046] The operator of the new fitting instrument may take appropriate action in response
to a display of the configuration information, e.g., by replacing the receiver, which
is appropriate in case adjustment of the hearing aid to the specific model of receiver
identified is not possible. In this way, undesired combinations of receiver, hearing
aid and hearing aid fitting parameters can be discovered and corrected.
[0047] Adjustment of the hearing aid and hearing aid parameters may be controlled internally
by said hearing aid.
[0048] Throughout the present disclosure, the "audio signal" may be used to identify any
analogue or digital signal forming part of a signal path from an input to an output
of the hearing aid.
[0049] Signal processing in the new hearing aid and in the new fitting instrument may be
performed by dedicated hardware or may be performed in a signal processor, or performed
in a combination of dedicated hardware and one or more signal processors.
[0050] As used herein, the terms "processor", "signal processor", "controller", "system",
etc., are intended to refer to CPU-related entities, either hardware, a combination
of hardware and software, software, or software in execution.
[0051] For example, a "processor", "signal processor", "controller", "system", etc., may
be, but is not limited to being, a process running on a processor, a processor, an
object, an executable file, a thread of execution, and/or a program.
[0052] By way of illustration, the terms "processor", "signal processor", "controller",
"system", etc., designate both an application running on a processor and a hardware
processor. One or more "processors", "signal processors", "controllers", "systems"
and the like, or any combination hereof, may reside within a process and/or thread
of execution, and one or more "processors", "signal processors", "controllers", "systems",
etc., or any combination hereof, may be localized on one hardware processor, possibly
in combination with other hardware circuitry, and/or distributed between two or more
hardware processors, possibly in combination with other hardware circuitry.
[0053] Also, a processor (or similar terms) may be any component or any combination of components
that is capable of performing signal processing. For examples, the signal processor
may be an ASIC processor, a FPGA processor, a general purpose processor, a microprocessor,
a circuit component, or an integrated circuit.
[0054] Below, the new method, hearing aid, and fitting instrument are explained in more
detail with reference to the drawings in which various examples are shown. In the
drawings:
Fig. 1 schematically illustrates an exemplary new hearing aid,
Fig. 2 shows in perspective a new RIE type hearing aid, and
Fig. 3 shows hearing aid circuitry for automatic configuration detection.
[0055] The new method, hearing aid, and fitting instrument will now be described more fully
hereinafter with reference to the accompanying drawings, in which various examples
of the new method, hearing aid, and fitting instrument are shown. The new method,
hearing aid, and fitting instrument may, however, be embodied in different forms and
should not be construed as limited to the examples set forth herein.
[0056] It should also be noted that the figures are only intended to facilitate the description
of the embodiments. They are not intended as an exhaustive description of the invention
or as a limitation on the scope of the invention. In addition, an illustrated embodiment
needs not have all the aspects or advantages shown. An aspect or an advantage described
in conjunction with a particular embodiment is not necessarily limited to that embodiment
and can be practiced in any other embodiments even if not so illustrated, or if not
so explicitly described.
[0057] Like reference numerals refer to like elements throughout. Like elements will, thus,
not be described in detail with respect to the description of each figure.
[0058] Figs. 1 - 3, and in particular Fig. 1, schematically illustrates a RIE hearing aid
10 comprising a first housing, namely a BTE hearing aid housing (not shown - outer
walls have been removed to make internal parts visible), to be worn behind the pinna
100 of a user. The BTE housing accommodates first circuitry 12 with at least one BTE
sound input transducer 14, 16, namely a front microphone 14 and a rear microphone
16 for conversion of an acoustic sound signal into respective microphone audio sound
signals, optional pre-filters (not shown) for filtering the respective microphone
audio sound signals, A/D converters (not shown) for conversion of the microphone audio
sound signals into respective digital microphone audio sound signals that are input
to a processor 18 configured to generate a hearing loss compensated output signal
based on the input digital audio sound signals.
[0059] The hearing loss compensated output signal is transmitted through a line 44 (not
visible) with electrical wires contained in a sound signal transmission member 20
to a receiver 22 of second circuitry 24 accommodated in a second housing (not shown
- outer walls have been removed to make internal parts visible). The receiver 22 provides
an acoustic output signal for transmission towards the eardrum of the user, based
on the hearing loss compensated output signal. The second housing constitutes an earpiece
62 with an outer shape that is configured to be comfortably positioned in the ear
canal of the user for fastening and retaining the receiver 22 and the sound signal
transmission member 20 in their intended positions in the ear canal of the user as
is well-known in the art of BTE hearing aids.
[0060] The earpiece 62 with the sound transmission member 20 is connected to the BTE housing
with a connector 30 for easy connection and removal of the earpiece 62.
[0061] The earpiece 62 comprises the sound transmission member 20. A large number of different
earpieces may be connected to the BTE housing with the connector 30, such as with
earpieces accommodating
- a) one receiver and zero microphones,
- b) one microphone and zero receivers,
- c) one receiver and one microphone positioned for preservation of directional cue,
- d) one receiver and one microphone positioned for suppressing occlusion,
- e) one receiver and two microphones (directional cue and occlusion), etc.
[0062] The above-mentioned earpieces may further have receivers with different power ratings,
e.g. 4 different ratings, and may further have sound tube members 20 of different
lengths, e.g. 5 different standard lengths.
[0063] Still further, earpieces are provided configured for the left ear and earpieces are
provided configured for the right ear.
[0064] Yet still further, some earpieces may be provided with other sensors, such as temperature
sensors, pressure sensors, directional sensors, etc.
[0065] Thus, a large variety of ear pieces may easily be provided; and thus, automatic detection
of the ear piece actually connected to the BTE housing with the connector 30 is highly
advantageous, e.g. in order to avoid mistakes.
[0066] The earpiece 62 shown in the figures accommodates one In-the-Ear (ITE) microphone
26 that is positioned at the entrance to the ear canal when the earpiece 62 is positioned
in its intended position in the ear canal of the user. The ITE microphone 26 is connected
to an A/D converter (not shown) and optionally to a pre-filter (not shown) in the
BTE housing, with interconnecting electrical wires (not visible) contained in the
sound transmission member 20.
[0067] The BTE hearing aid 10 is powered by battery 28. The battery 28 may be rechargeable.
[0068] In use, the ITE microphone 26 is positioned at an entrance to an ear canal of the
user. In this position, the output signal of the ITE microphone, in the following
denoted the ITE audio sound signal, generated by the ITE microphone 26 in response
to acoustic sound received by the ITE microphone 26, preserves spatial cues of the
received acoustic sound signal; or, in other words, the ITE microphone 26 is positioned
so that its transfer function constitutes a good approximation to the Head Related
Transfer Functions of the user.
[0069] The processor 18 conveys the directional information contained in the ITE audio sound
signal to the hearing loss compensated output signal thereby also preserving spatial
cues so that the user maintains his or her localization capability.
[0070] The ITE microphone 26 operates proximate the receiver 22 so that risk of feedback
is high, which limits the maximum stable gain available with the hearing aid 10.
[0071] However, in the hearing aid 10, output signals of the microphones 14, 16 and the
ITE microphone 26 are subjected to signal processing, e.g. adaptive filtering as for
example explained in more detail in European patent application No.:
12199761.3, in such a way that spatial cues are preserved and conveyed to the user of the hearing
aid while feedback is simultaneously suppressed.
[0072] As mentioned above, a microphone may be accommodated in the second housing, i.e.
in the earpiece 62, for suppressing occlusion. The microphone is positioned inside
the ear canal proximate the ear drum when the earpiece 62 is positioned in its intended
position in the ear canal of the user.
[0073] Typically, occlusion of the ear canal by the second housing (earpiece) leads to an
altered user perception of the user's own voice.
[0074] Sounds originating from the vocal tract (throat and mouth) are transmitted into the
ear canal through the cartilaginous tissue between these cavities and the outer portion
of the ear canal.
[0075] When nothing is positioned in the ear canal, most of this predominantly low frequency
sound simply escapes from the ear canal. However, when the ear canal is blocked these
bone-conducted sounds cannot escape from the ear canal. The result is a buildup of
high sound pressure levels in the residual ear canal volume. This increase in low
frequency sound pressure is audible and will cause them to hear their own voice as
loud and boomy. Change in perception of own voice is the most dominant occlusion related
complaint, but not the only one. Other occlusion related problems include too much
amplification at low frequencies for hearing aid users with good low frequency hearing,
reduced speech intelligibility, poorer localization, physical discomfort and increased
risk of external ear irritation and infection. Hearing aid users do not adapt to occlusion
and the occlusion effect has been cited by as many as 27% of hearing aid wearers as
a reason for dissatisfaction with their hearing aids. This emphasizes the need for
alleviating or, even better, eliminating the occlusion effect.
[0076] As explained in more detail in
EP 2 434 780 A1, the receiver may compensate for the body conducted sound based on an output signal
of the microphone positioned proximate the ear drum when the earpiece is positioned
in its intended position in the ear canal of the user, so that the user perceives
to listen to the hearing loss compensated signal only, whereby the occlusion effect
is suppressed.
[0077] Fig. 2 shows the new hearing aid 10 in its operating position with the BTE housing
60 behind the ear, i.e. behind the pinna 100, of the user. As illustrated, the new
hearing aid 10 may have an arm 64 that is flexible and intended to be positioned inside
the pinna 100, e.g. around the circumference of the conchae behind the tragus and
antitragus and abutting the antihelix and at least partly covered by the antihelix
for retaining the earpiece 62 in its intended position inside the outer ear of the
user. The arm may be pre-formed during manufacture, preferably into an arched shape
with a curvature slightly larger than the curvature of the antihelix, for easy fitting
of the arm into its intended position in the pinna 100.
[0078] Fig. 2 also schematically illustrates a new fitting instrument 70 and its wireless
interconnections with the Internet 200 and the new BTE hearing aid 10 shown in its
operating position with the BTE housing 60 behind the ear, i.e. behind the pinna 100,
of the user.
[0079] Configuration information may be transmitted wirelessly 80 to the fitting instrument
70, e.g. to be displayed on a display of the fitting instrument 70 for verification
by the operator of the fitting instrument 70, and possible corrective action in the
event that the detected type of earpiece is not of the desired type.
[0080] The fitting instrument 70 is configured for fitting the hearing aid 10 in accordance
with the configuration information.
[0081] The fitting instrument 70 has a processor 72 that is configured for responding to
the configuration information received from the hearing aid 10.
[0082] The fitting instrument may be configured to access a remote server through the Internet
200, e.g. to access a data base for further information on the hearing aid 10, e.g.
based on the received configuration information, e.g. with new values of fitting parameters
relating to a new type of earpiece 62.
[0083] Fig. 3 shows a block diagram of the hearing aid circuitry 12, 24 for automatic configuration
detection. In Fig. 3, the second circuitry 24 is accommodated in the second housing,
i.e. the earpiece 62; however, in another example, the second circuitry 24 may be
accommodated in the connector 30.
[0084] The second circuitry 24 comprises the receiver 22 and a transmitter 40 in the form
of a microcontroller 40 configured for transmission of a code that uniquely identifies
the type of ear piece 62 with the second circuitry 24, e.g. the transmitted code contains
the configuration information, e.g. the power rating of the receiver 22, whether the
ear piece 62 is for the left ear or the right ear, and possibly the length of the
sound transmission member 20, and possibly the number and types (occlusion and/or
spatial cue) of microphones 26, and possibly the number and types of other sensors,
etc.
[0085] The receiver 22 is driven by receiver driver 42 accommodated in the first housing,
namely the BTE-housing 60. During normal operation of the hearing aid 10, the receiver
driver 42 transmits the hearing loss compensated sound signal to the receiver on line
44 in the sound transmission member 20.
[0086] During boot-up of the hearing aid 10, the receiver driver 42 transmits a high frequency
signal, preferably of a frequency above 20 kHz, on line 44. The high frequency signal
charges capacitor 46 through diode 48, and the charged capacitor 46 subsequently supplies
power to the transmitter (microcontroller) 40 during transmission of the code on line
44.
[0087] The high frequency signal is further low pass filtered in low pass filter 50 and
input to the microcontroller 40 that is configured for detection of presence of the
high frequency signal. The microcontroller 40 is further configured for transmission
of the code on line 44 upon seizure of the high frequency signal.
[0088] The microcontroller 40 is configured for transmission of the code by intermittently
short-circuiting line 44 thereby generating a series of voltage drops of the supply
voltage of the circuitry in the BTE housing that is detected by a comparator 52 of
the first circuitry 12 in the BTE housing 60 already present for monitoring the voltage
supply of the circuitry.
[0089] Thus, the code is transmitted and decoded using signal lines for transmission of
an audio signal to the receiver, always present in a hearing aid, and without adding
circuitry in the BTE housing.
[0090] The second circuitry 24 may be configured to transmit the configuration information
repeatedly until power is no longer available from the power supply of the second
circuitry, e.g. charged capacitor 46, or, the second circuitry 24 may be configured
to transmit the configuration information repeatedly until receipt of an acknowledge
signal from the first circuitry that the configuration information has been successfully
received, e.g. by emission of the high frequency signal for a predetermined time period.
1. A hearing aid (10) having
a first housing (60) accommodating first circuitry (12),
a second housing (62) accommodating second circuitry (24), and
a connector (30) configured for interconnection of the first circuitry (12) with the
second circuitry (24), wherein the connector (30) comprises
a line (44) for transmission of a first signal between the first circuitry (12) and
the second circuitry (24), wherein
the second circuitry (24) includes a transmitter configured for transmission of a
second signal with configuration information to the first circuitry (12) utilizing
the line (44), and wherein the first signal does not contain the configuration information.
2. A hearing aid (10) according to claim 1, wherein the first signal is an audio signal
representing sound.
3. A hearing aid (10) according to claim 1 or 2, wherein the second circuitry (24) includes
a power supply that is charged with a third signal transmitted on the line (44).
4. A hearing aid (10) according to any of the previous claims, wherein the second circuitry
(30) includes a receiver (22).
5. A hearing aid (10) according to claim 4, wherein the line is an input line of the
receiver (22).
6. A hearing aid (10) according to any of the previous claims, wherein the transmitter
is configured for transmitting the second signal with at least one varying signal
parameter selected from the group consisting of amplitude, frequency, phase, and pulse
width.
7. A hearing aid (10) according to any of the previous claims, wherein the second signal
is modulated, and wherein the modulation is selected from the group consisting of
amplitude modulation, frequency modulation, and phase modulation.
8. A hearing aid (10) according to any of the previous claims, wherein the second signal
is modulated digitally, and wherein the digital modulation is selected from the group
consisting of phase-shift keying, frequency-shift keying, amplitude-shift keying,
and quadrature amplitude modulation.
9. A hearing aid (10) according to any of the previous claims, wherein the transmitter
is configured for transmitting the second signal by short-circuiting the line (44).
10. A hearing aid according to any of the previous claims, wherein the configuration information
includes:
an identifier of a component of the second circuitry (24); or
an identifier of a combination of components included in the second circuitry (24).
11. A hearing aid (10) according to any of the previous claims, wherein the first housing
(60) is a behind-the-ear housing and the second housing (62) is an in-the-ear housing.
12. A fitting instrument (70) for a hearing aid (10), configured for reception of the
configuration information.
13. A fitting instrument (70) according to claim 12, configured for fitting the hearing
aid in accordance with the configuration information.
14. A fitting instrument (70) according to claim 12 or 13, configured for displaying a
message in response to the configuration information.
15. A method of configuring a hearing aid (10) having a connector (30) that interconnects
first circuitry (12) of the hearing aid with second circuitry (24) of the hearing
aid (10), the connector (30) having a line (44) configured to transmit a first signal
between the first circuitry (12) and the second circuitry (24), the method comprising
transmitting a second signal containing configuration information relating to the
second circuitry (24) to the first circuitry (12) using the line (44), wherein
the first signal does not contain the configuration information.