Note: Descriptions are shown in the official language in which they were submitted.
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LIGHT APPLICATORS, SYSTEMS AND METHODS
Technical Field
[0001] The present invention relates to light irradiation of skin surfaces.
More
particularly, the invention relates to light applicators, systems comprising
light
applicators, and methods for their use.
Background
[0002] Various devices, systems and methods are known for providing
relaxation
and/or therapeutic effects by irradiating a patient's body surface with light.
Some
example devices, systems and methods are described and illustrated in the
commonly-assigned US Patent No. 7,959,656 and US Patent Application Serial No.
11/860457, which are hereby incorporated by reference herein in their
entirety.
Summary of the Invention
[0003] Embodiments of the present invention are directed to light
applicators,
systems comprising light applicators, and methods for their use.
[0004] According to one aspect of the invention, there is provided a light
applicator. The light applicator may comprise one or more solid-state light
emitters for
generating light to irradiate a subject's body surface. The solid-state light
emitters may
be laser diodes, LEDs (light emitting diodes), or some other solid-state light
sources.
In some embodiments, the light applicator may be a laser applicator having one
or more
light-emitting laser diodes. In some embodiments, the one or more solid-state
light
emitters may comprise one or more low-power light emitters. The term "low-
power"
herein means having a power output in the range of about 10mW to about 100mW.
In
some embodiments, the one or more solid-state light emitters may comprise one
or
more low-power light emitters having a power output in the range of about 30mW
to
about 40mW. In some embodiments, the one or more solid-state light emitters
may
comprise one or more medium-power light emitters. The term "medium-power"
herein
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means having a power output in the range of about 80mW to about 160mW. When
powered by suitable electric power, the one or more solid-state light emitters
may emit
light in the visible and/or infrared spectrum. For example, the light emitters
may emit
light in the range of 390 nm to 999 nm (for example, in the range of 635nm to
680 nm,
or in the range of 780 nm to 980 nm, or in some other range).
[0005] The light applicator is configured for contacting and
irradiating a subject's
body surface. The light applicator may comprise one or more electronic
components
(e.g., a control unit, a memory, one or more sensors, and circuitry) for at
least one of
generating, transmitting, recording, processing, storing and reporting
electronic signals
and/or other information useful for modulation of the light emitters.
[0006] In some embodiments, the light applicator is used
independently. The light
applicator may comprise an internal power supply (e.g., a battery).
[0007] In some embodiments, the light applicator is configured to
communicate
and cooperate with an external light control device. The light control device
may
comprise a power supply, a processor, a memory, circuitry, one or more input
units
(e.g., buttons, dials, keypad, keyboard, or touchscreen, etc.), one or more
output units
(e.g., a display screen). The light control device provides power for driving
the light
emitters. The light control device is also configured for at least one of
generating,
transmitting, recording, processing, storing and reporting electronic signals
and/or
other information useful for modulation of the light emitters.
[00081 According to one aspect of the invention, the light applicator
comprises a
housing which defines an internal compartment. The housing comprises a
treatment
plate for contacting a subject's body surface. The treatment plate has an
outer side and
the inner side. The outer side is the side for contacting a subject's body
surface. The
treatment plate comprises one or more windows. Windows could be openings
(e.g.,
cutouts in the treatment plate) or could be covered or filled with a material
substantially
transparent to the light emitted by the light emitters. The light applicator
also
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comprises one or more light emitters inside the housing, the one or more light
emitters
being configured to emit light toward the one or more windows of the treatment
plate.
The light applicator also comprises a heat spreader plate inside the housing.
The heat
spreader plate is in physical contact with one or more of the light emitters.
In some
embodiments, the treatment plate comprises one or more heat conducting members
(e.g., bosses) extending on the inner side of the treatment plate, and the
heat spreader
plate is in physical contact with the one or more of the heat conducting
members
extending from the treatment plate. In some embodiments, the one or more heat
conducting members (e.g., bosses) are part of the heat spreader plate and
extend from
the heat spreader plate to be in physical contact with the treatment plate. In
some
embodiments, both the heat spreader plate and the treatment plate comprise one
or
more heat conducting member (e.g., bosses), wherein the one or more heat
conducting
members of the heat spreader plate extend to contact the treatment plate and
the one or
more heat conducting members of the treatment plate extend to contact the heat
spreader plate. In some particular embodiments, the one or more heat
conducting
members of the heat spreader plate extend to contact the corresponding one or
more
heat conducting members of the treatment plate. In some embodiments, the one
or
more heat conducting members are independent structures separate from the heat
spreader plate and the treatment plate, but are in physical contact with both
the heat
spreader plate and the treatment plate. The contacts between the heat spreader
plate
and the light emitters and between the heat spreader plate and the treatment
plate via
the heat conducting members thereby create a heat conduction path from the one
or
more of the light emitters to the treatment plate via the heat spreader plate.
The heat
spreader plate and the treatment plate and the heat conducting members are
made of a
thermally conductive material, e.g., aluminum.
[0009] The heat spreader plate may be maintained in physical contact
with the one
or more of the light emitters and the one or more heat conducting members due
to the
physical dimensions of these parts and the constraints imposed by their
arrangement
and the dimensions of the internal compartment defined by the housing.
Additionally
or alternatively, the heat spreader plate may be maintained in physical
contact with the
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one or more of the light emitters and the one or more heat conducting members
by
fastening means.
[0010] In some embodiments, the heat spreader plate comprises one or
more
openings therein corresponding to the one or more light emitters. Each one of
the one
or more light emitters is at least partially located in a corresponding one of
the one or
more openings in the heat spreader plate. Each one of the one or more light
emitters
has at least a portion that is in physical contact with a wall of the
corresponding one of
the one or more openings in the heat spreader plate. In some embodiments, each
light
emitter has a head portion and a bezel portion. The bezel portion of each one
of the
light emitters is located in a corresponding one of the openings and is held
in physical
contact with the wall of the opening. The wall of the opening may have a shape
that
conforms to the shape of the light emitter or the bezel portion thereof to
achieve good
thermal contact.
[0011] In some embodiments, it is not required to have the heat
spreader
component as an intermediate medium. The heat conducting members (e.g.,
bosses)
could interface directly with the individual light emitters. In some
embodiments, it is
also possible to have the light emitters arranged in such a manner that the
light emitters
contact directly with the treatment plate or some other part of the housing of
the light
applicator, without having heat conducting members (e.g., bosses) or the heat
spreader
plate.
[0012] Although some embodiments of the present invention utilizes
the patient as
a heat sink, it is not mandatory that the outer case of the light applicator
that is not
directly apposed on the patient be either rigid or thermally conductive. For
example,
the outer case of the light applicator may be made of a flexible or
elastomeric material
into which a thermally conductive treatment surface (or treatment surfaces)
could be
located. For example, a light applicator according to some embodiment may be
designed like a "belt" wherein there are multiple "treatment faces" located in
a longer
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"belt" form.
[0013] In some embodiments, the light applicator comprises a printed
circuit board
inside the housing. The one or more light emitters may be mounted on the
printed
circuit board. The one or more electronic components (e.g., a control unit, a
memory,
one or more sensors, and circuitry) may also be mounted on the board. The one
or
more electronic components may function to communicate with the external light
control device and/or sense or modulate one or more parameters of the light
emitters
and/or process and store information. The printed circuit board may comprise a
connector which connects the light applicator to the external light control
device. In
some embodiments, the connector may be a wireless connector which enables the
light
applicator to communicate with the light control device wirelessly.
[0014] In some embodiments, the light applicator comprises at least
two printed
circuit boards inside the housing: a first printed circuit board and a second
printed
circuit board. Either the first printed circuit board or the second printed
circuit board or
both may comprise the electronic components for communicating with the
external
light control device and/or sensing or modulating one or more parameters of
the light
emitters and/or processing and storing information. In some particular
embodiments,
the one or more light emitters are mounted on the first printed circuit board,
and the
electronic components for communicating with the external light control device
and/or
sensing or modulating one or more parameters of the light emitters and/or
processing
and storing information are mounted on the second printed circuit board.
[0015] In some embodiments, the first printed circuit board and the second
printed
circuit boards are spaced apart from each other inside the housing, and the
heat
spreader plate is disposed between the first printed circuit board and the
second printed
circuit board. For example, the second printed circuit board may be disposed
in a space
between the treatment plate and the heat spreader plate.
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100161 In some embodiments, the light applicator may comprise one or
more
printed circuit boards, and one of the one or more printed circuit boards may
be
disposed between the treatment plate and the heat spreader plate. The printed
circuit
board between the treatment plate and the heat spreader plate may comprise one
or
more openings which allow the one or more corresponding heat conducting member
(of the treatment plate and/or the heat spreader plate) to extend through the
one or more
openings such that the heat spreader plate and the treatment plate are
thermally
connected via the one or more heat conducting members. With this
configuration, a
heat conducting path from the heat spreader plate to the treatment plate via
the heat
conducting members is maintained despite the presence of the second printed
circuit
board between the heat spreader plate and the treatment plate.
[0017] In some embodiments, the heat spreader plate comprises one or
more
openings corresponding to the one or more light emitters of the light
applicator. The
heat spreader plate is disposed between the first printed circuit board and
the second
printed circuit board. The one or more light emitters are mounted on the first
printed
circuit board. The one or more light emitters may extend from the first
printed circuit
board through the one or more corresponding openings in the heat spreader
plate and
toward the second printed circuit board and the treatment plate. In some
embodiments,
each light emitter has a head portion and a bezel portion. The bezel portion
of each one
of the light emitters is located in one of the corresponding openings and is
held in
physical contact with the wall of the opening. The wall of the opening may
have a
shape that conforms to the shape of the light emitter or the bezel portion
thereof to
achieve good thermal contact.
[0018] According to one aspect of the invention, there is provided a
lipolysis
system comprising at least one light applicator as described herein, and a
light control
device which comprises hardware, circuitry and software configured for at
least one of
generating, transmitting, recording, processing, storing and reporting
electronic signals
and/or other information for controlling operation of the light emitters of
the at least
one light applicator. In some embodiments, the system comprises a plurality of
light
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applicators, each one of the light applicators in communication with the light
control
device. The light control device may comprise a power supply, a processor, a
memory,
circuitry, one or more input units (e.g., buttons, dials, keypad, keyboard, or
touchscreen, etc.), and one or more output units (e.g., a display screen). The
power
supply of the light control device provides power to the light emitters of the
light
applicators.
[0019] According to one aspect of the invention, there are provided
methods for the
use of the lipolysis systems and/or the light applicator of the present
invention. In some
embodiments, the method comprises contacting the treatment plate of the light
applicator with a target portion of a subject's body surface, turning on the
light emitters
of the light applicator, and providing light irradiation of the target portion
of the
subject's body portion for a selected period of time. The method may comprise
conducting heat generated from the light emitters to the treatment plate and
further to
the subject's body surface. The method may also comprise manipulating an
external
light control device to communicate with the light applicator to regulate the
light
emitters of the light applicator. The method may comprise manually or
automatically
modulating the light output by the light emitters of the light applicator.
Modulating the
light emitted by the light applicator may comprise modulating the current
and/or
voltage and/or some other parameter of the electric power supplied to the
light emitters
of the light applicator. The method may also comprise monitoring one or more
parameters of the light emitters and modulating one or more parameters of the
light
emitters based on the information obtained from the monitoring. The method may
comprise modulating one or more parameters of the light emitters to maintain
the light
emitters at a predetermined temperature or within a predetermined temperature
range.
In some embodiments, the method comprises contacting a plurality of light
applicators
with a plurality of target portions of a subject's body surface for
application of light
irradiation thereto.
[0020] Further aspects of the invention and features of various example
embodiments of the invention are described below.
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Brief Description of Drawings
[0021] In drawings which show non-limiting embodiments of the
invention:
[0022] Fig. 1 is a cross-sectional view of a portion of an example light
applicator
according to an example embodiment of the present invention.
[0023] Fig. lA is a cross-sectional view of a portion of an example
light applicator
according to another example embodiment of the present invention.
[0024] Fig. 1B is a cross-sectional view of a portion of an example
light applicator
according to another example embodiment of the present invention.
[0025] Fig. 2 is a perspective view of a light applicator according
to another
example embodiment of the present invention. In Fig. 2, the treatment plate is
shown
on top.
[0026] Fig. 3 is a perspective view of the Fig. 2 light applicator.
In Fig. 3, the back
plate is shown on top.
[0027] Fig. 4 is an exploded perspective view of the Fig. 2 light
applicator. In Fig.
4, the treatment plate is shown on top.
[0028] Fig. 5 is an exploded perspective view of the Fig. 2 light
applicator. In Fig.
5, the back plate is shown on top.
[0029] Fig. 6 is a cross-sectional view of the Fig. 2 light
applicator, taken along
lines A-A in Fig. 2.
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[0030] Fig. 7 is a perspective view of a light applicator according
to another
example embodiment of the present invention. In Fig. 7, the treatment plate is
shown
on top.
[0031] Fig. 8 is a perspective view of the Fig. 7 light applicator. In Fig.
8, the back
plate is shown on top.
[0032] Fig. 9 is a partially exploded perspective view of the Fig. 7
light applicator.
In Fig. 9, the treatment plate is shown on top.
[0033] Fig. 10 is a partially exploded perspective view of the Fig. 7
light applicator.
In Fig. 10, the back plate is shown on top.
[0034] Fig. 11 is a diagram showing a lipolysis system according to
an example
embodiment of the invention.
[0035] Fig. 12 is a diagram showing an example data structure for
recording data in
a memory of an example light applicator.
[0036] Fig. 13 is a diagram showing an example data structure for recording
data in
a memory of an example light control device in an example lipolysis system.
Detailed Description
[0037] Throughout the following description, specific details are set
forth in order
to provide a more thorough understanding of the invention. However, the
invention
may be practiced without these particulars. In other instances, well known
elements
have not been shown or described in detail to avoid unnecessarily obscuring
the
invention. Accordingly, the specification and drawings are to be regarded in
an
illustrative, rather than a restrictive, sense.
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[0038] Aspects of the present invention provide a light applicator
for contacting
and controllably irradiating a portion of a subject's body surfaces with light
in the
visible and/or infrared spectrum, systems comprising one or more of the light
applicators communicating with a light control device, and methods for the use
of the
applicators and/or the systems. The light applicator comprises one or more
solid-state
light emitters. In some embodiments, the light applicator is a laser
applicator which
comprises one or more light emitting laser diodes.
[0039] The inventors have determined that providing laser diodes or
some other
solid-state light emitters to irradiate a subject's body surface may lead to
considerable
amounts of heat being generated from the light emitters during prolonged
application
of light. In some instances, the light applicator may overheat, causing the
light
applicator to fail or malfunction. The inventors have determined that when the
light
emitters are overheated, the quality and/or quantity of light output become
inconsistent
thereby reducing treatment efficacy. Overheating of the light emitters may
also reduce
the lifetime of the light emitters. Also, light output varies with temperature
so changes
in temperature can result in variations in light output. For example, in a
case where a
light applicator is used to provide a series of treatments, the first
treatment when light
emitters are cool may provide increased light output while later treatments
after the
light emitters have heated up may provide reduced light output. This can be a
significant problem. The inventors have determined that it is desirable to
develop light
applicators wherein the light emitters can be maintained at a relatively
constant
temperature so that the light outputs of the light emitters can be maintained
at desired
levels during prolonged application of light.
[0040] The inventors have determined that it is desirable to conduct
the heat
generated by the light emitters to an outer surface of the light applicator,
and
subsequently into the subject's body surface when the light applicator is in
contact with
the subject's body surface. In many cases the light emitters will generate
enough heat
that it is impractical to rely on air conduction from relatively small light
applicators to
maintain thermal equilibrium with the light emitters kept at suitable
operating
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temperatures. A subject's body can serve as an effective heat sink for the
amount of
heat emitted by a typical light applicator. The heat may be effectively
transferred to the
subject's body by thermal conduction when the light applicator is in direct
contact with
the subject's skin.
[0041] Fig. 1 is a cross-sectional view of a portion of an example
light applicator
50 according to one example embodiment of the invention. Light applicator 50
has a
heat conducting path 70 from light emitter 60 to an outer surface of the light
applicator
which is configured to contact a subject's body surface. Light applicator 50
comprises
a treatment plate 52. Treatment plate 52 has an outer side 54 and an inner
side 56.
Treatment plate 52 has a window 57. Outer side 54 of treatment plate 52 is for
contacting a subject's body surface.
[0042] Treatment plate 52 comprises a heat conducting member 58 that
extends
from inner side 56 of treatment plate 52. Heat conducting member 58 may be in
the
shape of a hollow cylinder. Light applicator 50 comprises a light emitter 60.
Light
emitter 60 has a head portion 62 and a bezel portion 64. Bezel portion 64 is
in thermal
contact with active elements of light emitter 60 such that temperature of the
active
elements of light emitter 60 can be controlled by removing heat by way of
bezel portion
64. Light applicator 50 comprises a heat spreader plate 66. Heat spreader
plate 66 is in
physical contact with heat conducting member 58. Heat spreader plate 66 is
also in
physical contact with bezel portion 64 of light emitter 60. In the illustrated
embodiment, heat spreader plate 66 comprises an opening 68. Bezel portion 64
of laser
diode 60 is located inside opening 68. Bezel portion 64 is in physical contact
with a
wall of opening 68. The wall of opening 68 may be shaped to conform to the
shape of
light emitter 60 or bezel portion 64 to achieve good thermal contact.
[0043] Light emitter 60 is located such that light rays or some of
the light rays
generated by light emitter 60 can pass through window 57 and transmit to the
outside of
light applicator 50. For example, a top portion of head portion 62 of light
emitter 60
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may extend out of opening 68 and into a space defined by heat conducting
member 58
and in proximity of window 57. The contacts between heat spreader plate 66 and
light
emitter 60 and between heat spreader plate 66 and heat conducting member 58 of
treatment plate 52 thereby create a heat conduction path 70 (indicated by
arrows in Fig.
1) from light emitter 60 via heat spreader plate 66 and heat conducting member
58 to
treatment plate 52.
[0044] Heat spreader plate 66 may be maintained in physical contact
with light
emitter 60 and heat conducting member 58 of treatment plate 52 due to the
physical
dimensions of these parts and the constraints imposed by their arrangement
within light
applicator 50. Additionally or alternatively, heat spreader plate 66 may be
maintained
in physical contact with light emitter 60 and heat conducting member 58 by
fastening
means (not shown in Fig. 1).
[0045] Fig. lA is a cross-sectional view of a portion of another example
light
applicator 50A. Light applicator 50A is similar to light applicator 50.
However, in
light applicator 50A, heat conducting member 58 extend from treatment plate
52, heat
conducting member 59 extend from heat spreader plate 66, and heat conducting
members 58, 59 extend toward one another and come into physical contact.
[0046] Fig. 1B is a cross-sectional view of a portion of another
example light
applicator 50B. Light applicator 50B is similar to light applicator 50. In
Fig. 1B, an
example printed circuit board 80 is schematically shown. In Fig. 1B, printed
circuit
board 80 is disposed in a space between treatment plate 52 and heat spreader
plate 66.
[0047] An example light applicator 10 according to one example
embodiment of
the invention is illustrated in Figs. 2-6. One of the advantageous features of
light
applicator 10 is that it provides heat conducting paths which allow heat
generated by
light emitters (e.g., laser diodes 28) to be efficiently transferred to the
subject's body
surface and into the subject's body, thereby preventing overheating or
temperature
variation of the light emitters. The light applicator 10 comprises a diode
printed circuit
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board (diode PCB) 12 which comprises a power connector 14 for receiving power
from
a power supply, and a control printed circuit board (control PCB) 16 which
comprises a
control connector 18. Power connector 14 and control connector 18 may be
connected
via a cable 20 with a light control device 230 (shown in Fig. 11). Laser
diodes 28 are
mounted on diode PCB 12. Control PCB 16 may comprise onboard electronic
components for sensing one or more parameters of laser diodes 28 and/or
switching on
or off laser diodes 28 and/or processing and storing information as described
in more
detail below.
[0048] Light applicator 10 comprises a treatment plate 22 and a back plate
24. In
an assembled state, treatment plate 22 and back plate 24 form a housing which
houses
diode PCB 12 and control PCB 16 and other components of light applicator 10
which
are described further below.
[0049] Treatment plate 22 comprises one or more spaced-apart windows 26.
Windows 26 could be openings or could be covered or filled with a material
transparent
to light from laser diodes 28. One or more laser diodes 28 are electrically
connected to
diode PCB 12. A heat spreader plate 30 is disposed between control PCB 16 and
diode
PCB 12. Control PCB 16, heat spreader plate 30, and diode PCB 12 all have one
or
more apertures which correspond to the positions of the one or more laser
diodes 28. In
an assembled state, laser diodes 28 extend from diode PCB 12, through the
corresponding apertures of heat spreader plate 30 and control PCB 16 and
toward
windows 26 of treatment plate 22. The assembly of these parts of light
applicator 10
may be enabled by fasteners, e.g., fasteners 32. Fasteners 32 also can clamp
the various
parts together to ensure good thermal contact and heat transfer.
[0050] As best seen in Figs. 5 and 6, treatment plate 22 comprises
one or more
bosses 34 disposed on an inner side thereof Bosses 34 may be in the shape of
hollow
cylinders. The outer diameter of bosses 34 may be small enough to allow bosses
34 to
pass through the corresponding apertures in control PCB 16. The inner diameter
of
bosses 34 may be big enough to accommodate the corresponding laser diode 28
which
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may extend into boss 34. Bosses 34 extend through the apertures in control PCB
16 to
be in physical contact with heat spreader plate 30. Heat spreader plate 30 is
held in
positive contact with bezel portions 36 of laser diodes 28 to ensure good
thermal
contact and heat dissipation between heat spreader plate 30 and laser diodes
28. The
contact paths from laser diodes 28 (via bezels 36) to heat spreader plate 30
and to
treatment plate 22 (via bosses 34) create heat conduction paths to enable heat
generated
by laser diodes 28 to be effectively transferred to treatment plate 22. When
light
applicator 10 is held in positive contact with a subject's body surface during
treatment,
heat is transferred from treatment plate 22 to the subject's body. Heat
spreader plate 30
and/or treatment plate 22 are made of a thermally conductive material or
thermally
conductive materials, e.g., aluminum, copper, or the like.
[0051] The interlocking arrangement of diode PCB 12, heat spreader
plate 30,
control PCB 16 and bosses 34 of treatment plate 22 can provide a low-profile
form
factor. In the illustrated embodiment, control PCB 16 comprises a plurality of
apertures which receive the corresponding plurality of bosses 34 extending
from
treatment plate 22. Also heat spreader plate 30 comprises a plurality of
apertures which
receive the corresponding plurality of laser diodes 28 extending from diode
PCB 12.
Therefore, the presence of control PCB 16 and heat spreader plate 30 do not
necessarily
increase the thickness of light applicator 10. Also, control PCB 16 is located
in a space
between treatment plate 22 and heat spreader plate 30, and is protected by
being
sandwiched between treatment plate 22 and heat spreader plate 30.
[0052] The dual board (PCB) architecture (i.e., having a control PCB
and a diode
PCB separate from one another) is advantageous. It allows a control PCB to
potentially
work with different diode PCBs having various numbers of laser diodes or other
solid-state light emitters. For example, a control PCB does not have to change
if the
design of the diode PCB changes from an 8-laser to 12-laser configuration. The
dual
board (PCB) structure also significantly improves ease of serviceability. For
example,
in the case that a laser diode fails, a service technician to swap out the
diode PCB. This
could also reduce costs as the diode PCB which is swapped out does not carry
control
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components. In some embodiment, it is also possible to have two or more diode
PCB's, and each one of the two or more diode PCB's may carry one or more laser
diodes.
[0053] One aspect of the invention relates to a light applicator which
incorporates a
closed-loop feedback system. For example, the closed-loop feedback system may
comprise one or more sensors to monitor outputs or some other performance
parameters of the light emitters. The closed-loop feedback system may also
comprise a
control unit. The sensors may be integrated with the light emitters. Such
sensors may
be light sensors, optical sensors or some other suitable sensors. The sensors
transmit
information relating to the outputs or some other performance parameters of
the light
emitters to the control unit in the light applicator. The control unit uses
the information
to control and/or modulate the light emitters.
[0054] Individual light emitters may be calibrated at the point of
manufacture. For
example, a measurement device may be used to individually measure the light
output
of the light emitters for one or more sets of driving conditions. The light
output may
vary because of light emitter manufacturing tolerances. During this process,
parameters of the driving signal applied to the light emitter may be varied
until the
measurement device reads the required output value. Once this is reached, a
"set-point" corresponding to the amount of power to achieve the required
output value
is saved, e.g., in a non-volatile memory in the light applicator. In
operation, the sensors
continuously monitor the light output of the light emitters and the control
unit uses the
information from the sensors to make dynamic changes where required to ensure
that a
desired light output is maintained for the light emitters, e.g., over the life
of the light
emitters. The sensors may be used to continuously monitor each one of the
light
emitters individually. If the output of a light emitter weakens, the control
unit will
dynamically increase the amount of power to the light emitter in order to
normalize
light output to the "set-point".
[0055] In some embodiments, the light applicator may be calibrated
using a
CA 02824022 2013-08-15
- 16 -2-setpoint calibration protocol. In such a protocol, light output of a
light emitter is
measured at a first current, and also measured at a second current which is
different
from the first current. Based on these two measurements, a function (e.g., a
linear
function) may be generated to determine what light output is expected for some
different current (e.g., a current between the first current and the second
current).
[0056] With the closed-loop feedback feature, the sensors may sense
one or more
parameters of the light emitters and send signals to the control unit in the
light
applicator, which enables the performance of each individual light emitter to
be
monitored continuously or periodically or intermittently. Each light emitter's
current
is dynamically adjusted by the control unit such that the light output of the
light emitter
is adjusted to a desired value or within a desired range. The closed-loop
feedback
feature provides a number of advantages. For example, it mitigates any
variable
performance characteristics of the light emitters; it mitigates the effect of
declining
light output over the lifetime of each light emitter; and it mitigates the
effect of
declining light output caused by heating of the light emitter over the
treatment time.
[0057] The control unit may also process the information from the
sensors and
cause the information to be recorded in a non-volatile memory in the light
applicator.
For example, the control unit may cause information relating to light outputs
in one or
more treatment sessions to be recorded in the non-volatile memory.
[0058] One aspect of the invention relates to a light applicator
which incorporates
anti-loss-of-control features. For example, the output of each light emitter
is monitored
(e.g., using the closed-loop feedback feature as described above). If a light
emitter's
output changes suddenly and the change is not expected then the control unit
may
detect the change and automatically operate a control switch to shut down the
light
emitter. The closed-loop feedback system may poll the output performance of
individual light emitters at frequent intervals. If a large difference (A) of
light output is
detected between one time interval and another, a lock-down function may be
initiated
by the control unit, turning off all the light emitters immediately. The
applicator will
CA 02824022 2013-08-15
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go into a "malfunction mode".
[0059] One aspect of the invention relates to a light applicator
which incorporates
diagnostic capabilities and light emitter degradation metrics to ensure
consistent
treatment and to identify when the light applicator or one or more light
emitters need to
be replaced due to aging. This may be achieved using the closed-loop feedback
system
as discussed above. As those skilled in the art would understand, due to the
brightness
of the light, and/or due to the infrared nature of the light, it is typically
not possible to
tell by visual examination whether a light emitter has diminished light output
¨ a
measuring device needs to be used. Such a measuring device may be incorporated
into
the light applicator. For example, each of the light emitters may incorporate
an
integrated optical feedback sensor. Additionally or alternatively, sensors
which are
external to the light emitters could be used. For example, the photo sensors
could be
positioned lateral to the light emitter windows in line of sight of the
treatment surface.
If the sensors detect that the light output at some current is less than a
threshold output
value, the control unit may automatically shut down the light emitters.
[0060] The light applicator according to the present invention may
comprise other
safety sensor features. For example, the light applicator may comprise one or
more
thermal sensors. For example, the thermal sensors may be mounted on a printed
circuit
board, although this is not mandatory. Alternatively, the thermal sensors may
be
located on the inner side of the treatment plate. The thermal sensors are used
to
continuously monitor the temperature of the light emitters. The thermal
sensors send
temperature information to a control unit. The control unit compares the
measured
temperature with a reference value corresponding to a safety level. If the
temperature
exceeds the predetermined safety level, the light emitters will be
automatically shut
down by the control unit. In some embodiments, a thermal pad may be positioned
in
contact with a part of a housing of the applicator (e.g., the treatment
plate). The
thermal pad is a hard wired sensor on the power circuit which immediately cuts
the
power when a predetermined temperature is exceeded.
CA 02824022 2013-08-15
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[0061] The light applicator according to the present invention may
comprise one or
more proximity sensors (e.g., capacitive touch sensors). The proximity sensors
may be
located on the treatment plate or on a printed circuit board. An example
proximity
sensor 38 is shown in Fig. 6. In the Fig. 6 embodiment, proximity sensors 38
extend
from control PCB 16 and toward treatment plate 22. The proximity sensors are
used to
ensure that the treatment plate of the light applicator is correctly apposed
against a
subject's body surface before the light emitter will be turned on. When the
treatment
plate of the light applicator is properly apposed against the subject's body
surface, the
proximity sensors will send signals to the control unit to allow the light
emitters to be
turned on. The control unit will prevent the light emitters from being turned
on if the
light applicator is not properly placed against the subject's body surface.
This provides
supplementary eye-protection to the operator and/or the subject.
[0062] When the light applicator is not in use, the light applicator
may be stowed in
a storage unit (e.g., a paddle dock). The paddle dock may be a feature of the
light
control device. The paddle dock may incorporate a sensor (e.g., a Hall sensor/
magnetic
field sensor or the like) which detects when the light applicators are (or are
not)
correctly stowed in the paddle dock. In the event that the light applicator is
not
detected to be in the paddle dock (and it is not detected to be in contact
with the
subject's body surface) then the light emitters will not be turned on.
Alternatively or
additionally, the light applicator may comprise a sensor, such as a magnetic
field
sensor. One example of a suitable magnetic field sensor is a Hall sensor.
Other types
of sensors, such as RFID sensor or mechanical switches, could also be
suitable. The
magnetic field sensor may detect whether the light applicator is stowed in the
paddle
dock or outside the paddle dock. If the magnetic field sensor detects that the
light
applicator is in the paddle dock, the magnetic field sensor will send a signal
to the
control unit in the light applicator (or a processor in the light control
device) which in
turn will prevent the light emitters from being turned on. Additionally, if
the sensor
detects that the light applicator is stowed in the paddle dock, the sensor
sends signals to
the control unit which inhibits the light emitters from being turned on even
when the
proximity sensors have detected that the light applicator is placed against a
nearby
CA 02824022 2013-08-15
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surface. This feature addresses the potential issue that the proximity sensors
could
inadvertently allow the light emitters to be turned on when the light
applicator is placed
against a surface in the paddle dock.
[0063] The light applicator according to the present invention may comprise
a
communication monitoring sensor. If the communication monitoring sensor
detects a
loss of communication between the light applicator and the light control
device, the
sensor sends a signal to the control unit in the light applicator, and the
control unit turns
off the light emitters.
[0064] The light applicator may use lower-power circuit design to
minimize heat
generated by control components. Much of the heat generated in electronic
circuits is
produced during conversions between voltage levels. By performing most of the
required voltage conversion in the light control device and passing a voltage
close to
the required operating level to the light applicator, unwanted heat production
is reduced
significantly in the light applicator. Voltage regulation can be performed in
the light
control device, thereby limiting the number of components and the amount of
heat
generated in the light applicator. The voltage applied to the light emitter
circuit may be
kept as low as possible, consistent with proper operation, to limit heating of
the
associated components (e.g., control transistors and current sense resistors).
The
transistor and current sense resistor components form part of the control loop
determining the current in the light emitters. The transistor acts as a valve
that regulates
the amount of current flowing, while the current sense resistor measures the
amount of
current. Both these components generate heat in proportion to the voltage
across them.
By limiting the voltage to a low level consistent with proper operation,
undesired heat
production is reduced. The transistor and current sense resistor components
may be
mounted on a printed circuit board. In some embodiments, the transistor and
current
sense resistor components are thermally coupled to the treatment plate. In
some other
embodiments, the transistor and current sense resistor components are not
thermally
coupled to the treatment plate.
CA 02824022 2013-08-15
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[0065] In some embodiments the light control device is configured to
output a
variable voltage to the light applicator for driving the light emitters. In
some
embodiments, the one or more light applicators all receive the same voltage
from the
external light control device. This voltage level may be set to as low a value
as
practical, consistent with correct device operation, in order to limit the
heat generation
in the light applicator. The power supply may be interrupted for all the light
applicators
at once, using an emergency shutoff switch located on the external light
control device.
[0066] The light applicator according to the present invention may
utilize a fast
multi-drop communication protocol to ensure robust and intelligent operation.
For
example, RS485 may be used. RS485 is relatively immune to data corruption from
electrical noise. Additionally or alternatively, other wired or non-wired
communications modalities such as ethernet,
bluetooth, or the like, may be used
to provide communication between the light applicator and the light control
device. A
well-defined data communication protocol with robust error checking is
desirable to
ensure that instructions from the control device are correctly received (and
interpreted)
by the light applicator and vice versa (e.g. "turn on", "turn off', "run at XX
mW power
level" etc.). Similarly, it is desirable that the light control device
receives accurate
messages from individual light applicators. A reliable communication protocol
is
desirable when some or all of the control circuitry resides in the light
applicators
themselves, rather than in the light control device.
[0067] The light applicator may utilize a communication protocol that
can
auto-detect connection between the light applicator and the light control
device very
quickly, e.g., within one or two seconds for all light applicators, or 0.2
seconds for one
light applicator (e.g., a new communication data packet is sent every 0.2
seconds). This
means that the control device is able to remain in "real-time" control and
communication with each of the individual light applicators. The protocol may
auto-detect disconnection between the light applicator and the light control
device in 1
second or less.
CA 02824022 2013-08-15
-21 -
[0068] In addition to normal treatment operation, the communication
protocol may
support: factory calibration of individual light emitters on each light
applicator and /or
factory-uploading of treatment log-files stored within each light applicator.
The
communication protocol may command certain modes of operation that are useful
for
calibration but may not be needed during regular operation. For example,
individual
light emitters may be turned on or off such that their performance can be
measured
separately from the other emitters in the light applicator. The communication
protocol
data packet has an extensible format which allows it to be used to communicate
and
transfer any data that is logged and stored on the light applicator.
[0069] In some embodiments, the light applicator incorporates a
control unit and a
non-volatile memory. The control unit may cause a full history of the use of
the light
applicator from the first time it is used to be recorded and stored in the non-
volatile
memory. For example, each light applicator is able to maintain a full history
of the
performances of the light emitters, the light output of each individual light
emitters, and
any light emitter failures or malfunctions. This feature is advantageous as it
allows a
manufacturer or service provider to track how the light applicators are used
in the field.
When a customer sends a light applicator to the manufacturer or service
provider for
repair or trouble-shooting, the manufacturer or service provider will be able
to
determine how the light applicator was used and a full history of the
performances of
the light emitters. The manufacturer or service provider may generate a
database based
on such information. As this database of knowledge grows, the manufacturer or
service
provider may be able to provide better services and/or products to customers.
In
addition, the data in the database may help verify when any failures occurred
and/or
verify proper operation in case the light applicator did not fail.
[0070] The light applicator according to the present invention may
also comprise a
data-logging feature. The non-volatile memory of the light applicator may be
used to
maintain a non-volatile log file of all performed treatments. Treatment start
and stop
times as well as performance parameters of the light emitters may be recorded
in the
memory in the light applicator. For example, the light applicator memory may
record
CA 02824022 2013-08-15
- 22 -
data in a data structure that comprises one or more of the following items:
treatment
number, start time, end time, light emitter 1 output, light emitter 2
output....., and light
emitter N output. An example data structure 300 is schematically shown in Fig.
12.
Additionally or alternatively, the light control device may also comprise a
non-volatile
memory which is used to maintain a non-volatile log file of all performed
treatments of
all associated light applicators. Treatment start and stop times as well as
performance
parameters of the light emitters of each associated light applicator may be
recorded in
the memory of the light control device. The memory of the light control device
may
record data from a plurality of light applicators. For example, the light
control device
memory may record data in a data structure that comprises one or more of the
following
items: light applicator ID, treatment number, start time, end time, light
emitter 1 output,
light emitter 2 output....., and light emitter N output. An example data
structure 400 is
schematically shown in Fig. 13. Such a data structure may include additional
information such as one or more measured temperatures, an ambient temperature
reading, electrical parameters such as voltage and/or current supplied to one
or more of
the light emitters, times at which an output of a proximity sensor changes, a
count of
state changes of the proximity sensor during a treatment or the like.
[0071] Figs. 7-10 illustrate a light applicator 100 according to
another embodiment
of the present invention. Light applicator 100 is similar to light applicator
10 except
that light applicator 100 contains 4 laser diodes.
[0072] Although some of the embodiments described herein utilize
laser diodes as
the light emitters, this is not mandatory. Other solid-state light emitters,
such as LEDs
or some other solid-state light emitters may be used.
[0073] An exemplary lipolysis system 200 according to an example
embodiment of
the present invention is schematically illustrated in Fig. 11. System 200 may
comprise
one or more light applicators (e.g., light applicator 10) and a light control
device 230
configured for communicating and cooperating with the one or more light
applicators.
CA 02824022 2013-08-15
- 23 -
Light control device 230 may comprise a power supply, a processor, a memory,
circuitry, one or more input units (e.g., buttons, dials, keypad, keyboard, or
touchscreen, etc.), and one or more output units (e.g., a display screen). The
light
control device supplies power to the light emitters of the light applicators.
The light
control device may also be configured for at least one of generating,
transmitting,
recording, processing, storing and reporting electronic signals and/or other
information
useful for modulation of the light emitters.
[0074] According to one aspect of the invention, there are provided
methods for the
use of the lipolysis systems and/or the light applicators of the present
invention. In
some embodiments, the method comprises contacting the treatment plate of the
light
applicator with a target portion of a subject's body surface, turning on the
light emitters
of the light applicator, and providing light irradiation of the target portion
of the
subject's body portion for a period of time. The method may comprise
conducting heat
generated from the light emitters via heat conducting members to the treatment
plate
and further to the subject's body surface. The method may also comprise
manipulating
a light control device to communicate with the light applicator to regulate
the light
emitters of the light applicator. The method may comprise manually or
automatically
modulating the light emitters of the light applicator. Modulating the light
emitters of
the light applicator may comprise modulating the current and/or voltage and/or
some
other parameter of the electric power supplied to the light emitters of the
light
applicator. The method may also comprise monitoring one or more parameters of
the
light emitter (e.g., light output of the light emitter), sending information
to a control
unit, and modulating one or more parameters of the light emitters based on the
information. The method may comprise modulating the current and/or voltage
and/or
some other parameter of the electric power supplied to the light emitters to
maintain the
light output of the light emitters to be at a predetermined value or within a
predetermined range. The method may comprise modulating one or more parameters
of the light emitters to maintain the light emitters at a predetermined
temperature or
within a predetermined temperature range. In some embodiments, the method
comprises contacting a plurality of light applicators with a plurality of
target portions
CA 02824022 2013-08-15
- 24 -
of a subject's body surface for application of light irradiation thereto.
[0075] The light applicators, light control devices, and lipolysis
systems described
herein may optionally be used in accordance with the methods described and
illustrated
in the commonly-assigned US Patent No. 7,959,656 and US Patent Application
Serial
No. 11/860457, which are hereby incorporated by reference herein in their
entirety.
[0076] This application is intended to cover any variations, uses, or
adaptations of
the invention using its general principles. Further, this application is
intended to cover
such departures from the present disclosure as come within known or customary
practice in the art to which this invention pertains and which fall within the
limits of the
appended claims. Accordingly, the scope of the claims should not be limited by
the
preferred embodiments set forth in the description, but should be given the
broadest
interpretation consistent with the description as a whole.
