Patent ID: 12262453

DETAILED DESCRIPTION

Reference will now be made in detail to implementations and various aspects and variations of systems and methods described herein. Although several exemplary variations of the systems and methods are described herein, other variations of the systems and methods may include aspects of the systems and methods described herein combined in any suitable manner having combinations of all or some of the aspects described.

Systems and methods according to the principles described herein can power one or more light sources to reduce interference between the light sources and/or optical components in the same environment. For example, the light sources may be surgical lights located in the same environment as a video camera. The light sources may be operated using one or more power modulation signals. The light sources and optical component(s) may be operating at the same time and with one or more properties (such as frequency) that are the same, which may cause optical and/or electrical interference. The interference may prevent the optical component(s) from operating properly.

The systems and methods described herein can automatically vary the frequency of the power modulation signals. This variation in frequency may reduce the optical interference at certain frequencies and/or spread the interference over multiple frequencies. This can reduce or avoid optical interference by reducing or avoiding operation of optical components (including the light sources of interest) at the same frequency at the same time.

According to various aspects, the frequency may be varied using an oscillator that generates an input signal (e.g., a clock signal) based on one or more input frequencies (e.g., clock frequencies). The light sources may receive one or more control signals, generated based on the varied frequency. The light sources may be driven in accordance with the frequency varying across modulation periods. Optionally, the frequency may be varied randomly or pseudo randomly.

The systems and methods described herein can introduce phase modulation into the control signals for driving channels of light sources to reduce the electrical interference. The system may introduce a difference in phase in the control signals to at least two channels, reducing or avoiding simultaneous or synchronous driving of the channels. The light sources may be driven using control signals having a respective phase shift. Optionally, a plurality (e.g., all) of the channels may be driven using control signals, each having unique phase shifts. The phase shift for a given channel may be equal to a certain degrees divided by the number of channels. In some aspects, the different phase shifts may lead to asynchronous driving of the plurality of channels.

The systems and methods described herein can vary one or more properties in the power modulation signals using a plurality of oscillators, one or more controllers, or a combination thereof. Exemplary properties may include, but are not limited to, frequency, phase shift, delay, duty cycle, and power.

The methods for powering one or more light sources, according to the principles described herein, can be used intraoperatively for guiding a surgeon during a surgical procedure. For example, the light sources may illuminate target tissue of a subject during a surgical procedure. The one or more light sources may be powered using the described systems and methods for non-surgical applications, such as for diagnosis or in support of non-surgical treatments.

In the following description, it is to be understood that the singular forms “a,” “an,” and “the” used in the following description are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is also to be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It is further to be understood that the terms “includes, “including,” “comprises,” and/or “comprising,” when used herein, specify the presence of stated features, integers, steps, operations, elements, components, and/or units but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, units, and/or groups thereof.

Certain aspects of the present disclosure include process steps and instructions described herein in the form of an algorithm. It should be noted that the process steps and instructions of the present disclosure could be embodied in software, firmware, or hardware and, when embodied in software, could be downloaded to reside on and be operated from different platforms used by a variety of operating systems. Unless specifically stated otherwise as apparent from the following discussion, it is appreciated that, throughout the description, discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining,” “displaying,” “generating” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system memories or registers or other such information storage, transmission, or display devices.

The present disclosure in some examples also relates to a device for performing the operations herein. This device may be specially constructed for the required purposes, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a non-transitory, computer readable storage medium, such as, but not limited to, any type of disk, including floppy disks, USB flash drives, external hard drives, optical disks, CD-ROMs, magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, application specific integrated circuits (ASICs), or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus. Furthermore, the computers referred to in the specification may include a single processor or may be architectures employing multiple processor designs for increased computing capability. Suitable processors include central processing units (CPUs), graphical processing units (GPUs), field programmable gate arrays (FPGAs), and ASICs.

The methods, devices, and systems described herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may also be used with programs in accordance with the teachings herein, or it may prove convenient to construct a more specialized apparatus to perform the required method steps. The required structure for a variety of these systems will appear from the description below. In addition, the present invention is not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the present invention as described herein.

FIG.1illustrates a schematic representation of a lighting system100, according to some aspects. The lighting system100includes a surgical light102for illuminating target tissue104of a subject106with light from one or more light sources. The surgical light102includes a first light source108and a second light source110. The first light source108emits first light112having a first spectrum for illuminating the tissue104with the first light112. The second light source110emits second light114having a second spectrum for illuminating the tissue104with the second light114.

A spectrum (e.g., first spectrum and/or second spectrum) may be a continuous spectrum that has wavelengths of light in a range from a lowest wavelength to a highest wavelength, or can be a discontinuous spectrum in which at least some wavelengths between the lowest and highest wavelengths of the light having the respective spectrum are not present in the light, such as a spectrum provided by a combination of red, green, and blue emitters. In some aspects, the light (e.g., first light112or second light114) from a light source (e.g., first light source108or second light source110) does not have light in a portion of the visible spectrum, or the light in the portion of the visible spectrum is attenuated with respect to the relative contribution of that portion of the visible spectrum to the light emitted from the respective light source. The first and second light sources108and110can be simultaneously activated so that the first light112and the second light114can combine, either at the target or prior to reaching the target, to illuminate the target tissue104with a mixture of the first light112and the second light114. Thus, the tissue can be illuminated with light across a broad spectrum in which the relative contribution of light in the portion of the visible spectrum lacking from the second light114emitted by the second light source110is reduced with respect to the relative contribution of that portion of visible light relative to white light. In some aspects, reducing but not eliminating the relative amount of light in the portion of the visible spectrum lacking from the second light114of the second light source110(and thereby reducing but not eliminating the amount of that light that is reflected from the tissue) can preserve the normal appearance of the tissue while providing benefits to the user, such as improved contrast between features of the tissue, reduced fatigue, and/or reduced glare.

In some aspects, the first spectrum is broader than the second spectrum. For example, the first spectrum may be the visible spectrum. In some aspects, the first spectrum is narrower than the second spectrum but includes a portion of the visible spectrum lacking in the second spectrum. For example, the second spectrum may lack a given color, such as a red or blue, and the first spectrum may include just that color lacking from the second spectrum, such as the red or blue lacking from the second spectrum. According to various aspects, the first and/or second spectrums include non-visible light wavelengths, such as ultraviolet light and/or infrared light.

The lighting system100includes a controller122for controlling the first and second light sources108and110. The controller122can be a component of the surgical light102as shown, or may be operatively coupled to the surgical light102. The controller122controls the first and second light sources108and110such that the first and second light sources108and110emit the first and second lights112and114, respectively, for providing the first and second spectrum lights to the tissue. In some aspects, the controller122can control the first and second light sources108and110according to different operating modes. For example, in a first mode, both light sources are activated to provide the first and second lights112and114to the target tissue104, and in a second mode, the second light source110may be deactivated so that the target tissue is illuminated with only the first light112. In some aspects, a third mode may be included in which the first light source108is deactivated and the second light source110is activated so that the tissue is illuminated with just the second light114.

In some aspects, the surgical light102includes a housing124that houses the first and second light sources108and110. In some aspects, the controller122is housed within the housing124. The housing124may be mounted to a suspension arm assembly126so that the surgical light102can be suspended above subject106, such as above an operating table148in an operating room. The suspension arm assembly126can attach to the ceiling or other suitable support.

The first light source108includes one or more first light emitters116that individually or collectively generate the first light112. One or more optical elements130may be provided in front of the one or more light emitters116to manipulate the light emitted by the one or more light emitters for providing the light to the tissue of the subject106, such as by focusing, collimating, collecting, homogenizing, and/or directing the light. The one or more optical elements130can include, for example, one or more lenses, mirrors, collimators, and filters.

The second light source110includes one or more second light emitters118that individually or collectively generate the second light114. In some aspects, one or more filters120are provided to filter out a portion of the spectrum (entirely or at least a portion) attenuated from the second light114emitted by the second light source110. In these aspects, the light emitted by the one or more second light emitters118includes light in the portion of the spectrum attenuated from the second light114emitted by the second light source110, and the one or more filters120filter this light out so that the filtered portion of the spectrum is attenuated from the second light114provided by the second light source110. In some aspects, the second light source110includes one or more optical elements128for manipulating light from the one or more second light emitters118for providing the light to the tissue of the subject. The one or more filters120can be located in any suitable location along the light path from the one or more second light emitters118, including between the one or more second light emitters118and the one or more optical elements128, downstream of the one or more optical elements128, and/or directly on one or more surfaces of the one or more optical elements128.

The light emitters of one or more of the first and second light sources108and110, according to various aspects, can include any type of light emitter, such as incandescent (halogen lamp or a tungsten filament), discharge lamp, solid state, laser, or fluorescent light emitters. In some aspects, emitters of the first and second light sources108and110include one or more types of solid state light emitters such as one or more types of light-emitting diodes (LEDs), organic light-emitting diodes (OLED), superluminescent diodes (SLD), or polymer light-emitting diodes (PLED). In some aspects, light emitters of the first and second light sources108and110include narrow spectrum light emitters, such as red, green, and blue LEDs. In some aspects, light emitters of the first and second light sources108and110include broad spectrum light emitters, such as white light LEDs. In some aspects, the first and second light sources108and110have the same type or types of emitters. Alternatively, the first and second light sources108and110may have different types of emitters. In some aspects, the first and second light sources108and110can include phosphores. For example, in some aspects, the first and second light sources108and110may include emitters with different phosphores. In some aspects, the first and second light sources108and110both use at least one type of white light LED.

FIGS.2A-2Billustrate exemplary waveforms for driving one or more light sources using fixed frequency PWM. The frequency210may be the same for each modulation period (e.g., periods P1, P2, P3, P4, P5, etc.). To adjust the intensity with fixed frequency PWM signals, the duty cycle may be adjusted. For example, the first waveform220ofFIG.2Amay have a first duty cycle and a first ON time222, and the second waveform230ofFIG.2Bmay have a second duty cycle and a second ON time232. The second duty cycle (and second ON time232) may be greater than the first duty cycle (and first ON time222). As a result, the second waveform230may result in higher intensity than the first waveform220.

The environment may be equipped with one or more optical components other than the light source(s). For example, the environment may be equipped with surgical lights and other optical components. Exemplary optical components may include, but are not limited to, video cameras, pulse oximeters, optical navigation systems, light bulbs, personal electronic devices, and location sensors. The other optical components may be operated at the same time as the light sources. In some instances, one or more of the other optical component(s)/system(s) may be operating at the same frequency as the frequency210of the light source(s), which may cause optical and/or electrical interference.

Although the frequency210may be changed such that the light source(s) no longer interfere with one or more optical components, the changed frequency may interfere with other optical components. The other optical components may operate at different frequencies. For example, a first optical component may operate at a first frequency, and a second optical component may operate at a second frequency. The light source(s) may operate at the first frequency, but then may be switched to a different frequency to avoid or reduce interference with the first optical component. The light source(s) may be switched to the second frequency, which may lead to interference with the second optical component. The light source(s) may be switched again to operate a different frequency, but given the number of optical components that may exist within the operating room, it may be difficult to reduce or avoid interference.

Examples of the disclosure may include reducing interference by varying the frequency of the power modulation signals.FIG.3Aillustrates an exemplary waveform305for driving one or more light sources based on one or more power modulation signals having a frequency that varies across modulation periods, according to some aspects. The frequency may differ for each modulation period. For example, the power modulation signal305may have a first frequency310for a first modulation period P1, a second frequency312for a second modulation period P2, a third frequency314for a third modulation period P3, etc.

The frequency of the power modulation signal(s) may vary continuously, as shown in the figure. This variation in frequency may reduce interference at certain frequencies and/or spread the interference over multiple frequencies. For example, depending on the frequencies of the other optical components in operation at the same time (in the same environment), the light sources may interfere with the other optical components at the first frequency310, but not at the second frequency312. As another example, depending on the frequencies of the other optical components in operation at the same time, the light source(s) may interfere with only a first optical component at the first frequency310and only a second optical component at the second frequency312. In some aspects, a continuously varying frequency (of the power modulation signals) may have a frequency for the first modulation period P1 that is different from the frequency for the second modulation period P2, wherein the first modulation period P1 and the second modulation period P2 are consecutive periods.

In some aspects, the frequency of the power modulation signal(s) may vary randomly or pseudo randomly. That is, the frequency of the power modulation signal(s) may not be varied based on a pre-determined pattern. In some aspects, the frequency may vary for every modulation period. For example, as shown in the figure, the second frequency312for the second modulation period P2 may be different from the first frequency310for the first (adjacent) modulation period P1. The third frequency314for the third modulation period P3 may be different from the second frequency312for the second modulation period P2, etc. In some aspects, the third frequency314for the third modulation period P3 may be different from the first frequency310for the first modulation period P1.

In some examples, the duty cycle may vary across modulation periods. For example, during the first modulation period P1, the power modulation signals(s)305may have a first duty cycle330. During the second modulation period P2, the power modulation signal(s)305may have a second duty cycle332. During the third modulation period P3, the power modulation signal(s)305may have a third duty cycle334. Alternatively, in some aspects, the duty cycle of the power modulation(s) may be the same across modulation periods. Additionally, in some aspects, the duty cycle of the power modulation(s) may differ across modulation signals. The duty cycle may be adjusted for finer granularity control of the illumination field, for example.

Examples of the disclosure may also include driving different powers or the same power during ON times of at least two of the modulation periods.FIG.3Billustrates an exemplary waveform355for driving one or more light sources based on one or more power modulation signals having a power that varies across at least two modulation periods, according to some aspects. The driving may comprise driving different powers, such as power340, power342, and power344, during ON times of at least two of the modulation periods, such as modulation period P1, modulation period P2, and modulation period P3, respectively. Additionally or alternatively, the driving may comprise driving the same power, such as power346, during ON times of at least two of the modulation periods, such as modulation period P4 and modulation P5.

FIG.4Aillustrates an exemplary block diagram of a lighting system, according to some aspects. The lighting system400may comprise one or more controllers410, one or more oscillators420, one or more power circuits430, a converter432, and one or more light sources440. In some aspects, the controller(s)410may comprise one or more microcontrollers. In some aspects, the oscillator(s)420may comprise one or more spread spectrum oscillators. Although the figure illustrates controller(s)410, oscillator(s)420, power circuit(s)430, and converter432as separate, discrete circuits, examples of the disclosure may include one or more circuits as included in another circuit. For example, oscillator420may be included in controller410, converter432may be included in controller410, etc.

The controller(s)410may include one or more programmable registers. The programmable registers may be set to select which component generates an input signal. Exemplary components for generating an input signal may include, but are not limited to, the controller(s)410and an external clock source (e.g., oscillator(s)420). In some aspects, the controller410may provide the component (e.g., a spread spectrum oscillator) with one or more input frequencies (via signal422), and the component may generate an input signal424based on the one or more input frequencies. The input signal and input frequencies may comprise, e.g., a clock signal and clock frequencies, respectively.

In some aspects, the controller(s)410may generate one or more power modulation signals412based on the input signal. The power modulation signals412may comprise at least a first power modulation signal412A and a second power modulation signal412B. The power modulation signal(s) may have a frequency that varies across modulation periods, as described throughout this disclosure. In some aspects, the frequencies may vary independently among a plurality of power modulation signals.

The controller(s)410may provide the power modulation(s) to the power circuit(s)430. The converter432may receive a signal from the controller(s)410and may provide one or more linear signals434to the power circuit(s)430. The linear signals434may comprise at least a first linear signal434A and a second linear signal434B. The power circuit(s)430may receive the power modulation signal(s)412and/or linear signal(s)434and may generate one or more control signals442to drive the one or more light sources440. In some aspects, the control signal(s)442may be based on the power modulation signal(s)412, linear signal(s)434, or both. The light source(s)440may receive the control signal(s)442from the power circuit(s)430and emit light in response. In some aspects, each light source, such as light source440A and440B, may receive its own control signal from a unique power circuit, such as control signals442A and442B from power circuits430A and430B, respectively.

Examples of the disclosure may use one or more methods for controlling the intensity of the light emanating from one or more light sources. In some examples, the intensity may be controlled by using one or more linear signals. The one or more linear signals may be provided as control signals to drive the light source(s). The control signal may be, e.g., a current or voltage signal. Increased intensity may be achieved by driving a higher signal value (e.g., current), and decreased intensity may be achieved by driving a lower signal value. In some examples, the intensity may be controlled by using power modulation. Power modulation may comprise pulsing the light source(s), where the intensity may be controlled based on the proportion of ON time compare to OFF time of a given modulation period. Increased intensity may be achieved by driving a longer ON time, and decreased intensity may be achieved by driving a shorter ON time. Additionally or alternatively, the intensity of the light source(s) may be adjusted by changing the duty cycle of the power modulation signal(s). The duty cycle may be changed without changing the frequency (input to an oscillator, output from an oscillator, etc.).

In some aspects, different methods may be implemented for adjusting the intensity based on the input to or output from the light source(s). When one or more properties of the light source(s) meet a criterion, the intensity of the light source(s) may be controlled based on the linear signal(s). When the one or more properties of the light source(s) does not meet the criterion, the intensity of light source(s) may be controlled based on the power modulation signal(s). The criterion may be, as one non-limiting example, the input to or the output from the light source(s) being greater than or equal to a pre-determined level. As another non-limiting example, the criterion may be the light source(s) operating in a certain operating state. In this manner, any issues, such as those associated with color shifting and heating when operating the light source(s) at low intensity levels, may be reduced or avoided.

Examples of the disclosure include a comprising the lighting system400and one or more optical components located in the same environment (e.g., the same surgical room, medical facility, etc.). The optical component(s) may be located within the system or may be external from the system. Exemplary optical components may include, but are not limited to, a video camera, a pulse oximeter, an optical navigation system, and a location sensor.

FIG.4Billustrates an exemplary block diagram of a lighting system, according to some aspects. The lighting system450may comprise the lighting system400ofFIG.4Aincluding one or more controllers410, one or more oscillators420, one or more power circuits430, one or more converters432, and one or more light sources440. The lighting system450may also comprise other components including, but not limited to, interface circuits, switches, drivers, inputs and outputs, protection circuits, sensors, memory, filters, and power supplies.

FIG.5illustrates a block diagram of an exemplary method for powering one or more light sources of the disclosed lighting system, according to some aspects. The method500comprises a controller providing one or more input frequencies to an oscillator at step502. At step504, the oscillator may generate an input signal based on the one or more input frequencies. The controller may generate one or more power modulation signals based on the input signal at step506, where the power modulation signal(s) may have a frequency that varies across modulation periods. At step508, the one or more power circuits may receive the power modulation signal(s) and may generate one or more control signals to drive the light source(s).

During at least one modulation period, the frequency of at least one power modulation signal may be different from the frequency of at least another power modulation signal and/or the signal causing the operation of one or more optical components. The frequency of the power modulation signal(s) may vary across modulation periods. This difference (including the variation) in one or more frequencies may reduce or eliminate the amount of optical interference between the light sources in the lighting system and/or the optical component(s).

Examples of the disclosure may include introducing phase modulation across channels to reduce electromagnetic interference (EMI).FIG.6illustrates exemplary waveforms605and607for driving a plurality of channels having different phase shifts, according to some aspects. The first power modulation signal605may have a first phase shift622, and the second power modulation signal607may have a second phase shift624. The first phase shift622(of the first power modulation signal605) may be different from the second phase shift624(of the second power modulation signal607) during the same modulation period.

The difference in phase shifts between the power modulation signals may reduce the combined interference from the channels. In some aspects, different channels may be driving different light source(s). For example, referring back toFIG.4A, a first channel may be driving first light source(s)440A and a second channel may be driving second light source(s)440B. In some aspects, each channel may receive a unique set of control signals (including one or more power modulation signals412and/or one or more linear signals434). Depending on the phase shift of the control signals of the light sources and/or other optical components in operation at the same time (in the same environment), the light sources may interfere with each other and/or with the other optical components.

Referring back toFIG.6, in some aspects, the difference between the phase shift622of the first power modulation signal605and the phase shift624of the second power modulation signal607is the same over modulation periods, as shown in the figure. Alternatively, the difference between the phase shift622of the first power modulation signal605and the phase shift624of the second power modulation signal607may vary over modulation periods. This difference may vary randomly or pseudo randomly, for example. The phase shift of the power modulation signal(s) may not be varied based on a pre-determined pattern.

The difference between the phase shifts may be based on the number of power modulation signals, the number of channels, or both. As one non-limiting example, the phase shift for a given channel may be equal to a certain degrees divided by the number of channels, such as 36 degrees (360 degrees divided by 10 channels), 180 degrees (360 degrees divided by two channels), 90 degrees (360 degrees divided by four channels), etc. The phase shifts of the first, second, third, and fourth channels may be 0, 90, 180, and 270 degrees, respectively. In some aspects, the phase shift may reduce the power and noise by, e.g., the number of channels. For example, the power and noise may be reduced by a factor of four for four channels. The difference(s) between the phase shifts of two (or more) channels among the plurality of channels may be the same or different.

In some examples, the duty cycle may vary across modulation periods. For example, during the first modulation period P1, the power modulation signals(s)605may have a first duty cycle630. During the second modulation period P2, the power modulation signal(s)605may have a second duty cycle632. During the third modulation period P3, the power modulation signal(s)605may have a third duty cycle634. Alternatively, in some aspects, the duty cycle of the power modulation(s) may be the same across modulation periods. The duty cycle(s) for the second waveform may follow the same pattern (first duty cycle630, second duty cycle632, third duty cycle634, etc.) for multiple channels or may differ.

Examples of the disclosure may also include driving different powers or the same power during ON times of at least two of the modulation periods. Examples of the disclosure may, additionally or alternatively, use one or more methods for controlling the intensity of the light emanating from one or more light sources. In some examples, the intensity may be controlled by using one or more linear signals. The one or more linear signals may be provided as control signals to drive the light source(s). The control signal may be, e.g., a current or voltage signal. Additionally or alternatively, the intensity of the light emanating from the light source(s) may be adjusted by changing the duty cycle of the power modulation signal(s). The duty cycle of the power modulation signal(s) may be changed without changing other signals (input to an oscillator, output from an oscillator, etc.). In some aspects, different methods may be implemented for adjusting the intensity based on the input to or output from the light source(s). When the input to or the output from the light source(s) is greater than or equal to a pre-determined level, the intensity of the light emanating from the light source(s) may be controlled based on the linear signal(s). When the input to or the output from the light source(s) is less than the pre-determined level, the intensity may be controlled based on the power modulation signal(s).

The power modulation signals605and607ofFIG.6may be generated from the lighting system shown inFIGS.4A and4B. The controller410may provide the component (e.g., an oscillator such as a spread spectrum oscillator) with one or more input frequencies (via signal422), and the component may generate an input signal424based on the one or more input frequencies. The input signal424and input frequencies may comprise, e.g., a clock signal and clock frequencies, respectively.

The controller410may generate a plurality of power modulation signals412based on the input signal424. The plurality of power modulation signals412may have different phase shifts relative to one another. For example, the first power modulation signal412A may have a first phase shift, and the second power modulation signal412B may have a second phase shift. The controller(s)410may provide the power modulation signal(s)412to the power circuits430and/or to the converter432. The converter432may receive the signal from the controller(s)410and may provide one or more linear signals434to the power circuit(s)430. The power circuit(s)430may receive the plurality of power modulation signals412and/or linear signal(s)434and may generate one or more control signals442to drive the one or more light sources440.

In some aspects, the control signal(s)442may be based on the power modulation signal(s)412, linear signal(s)434, or both. The light source(s)440may receive the control signal(s)442from the power circuit(s)430and emit light in response. In some aspects, the first light source440A may receive the first power modulation signal412A, and the second light source440B may receive the second power modulation signal412B.

In some aspects, the lighting system400may be located in the same environment as one or more optical components (e.g., a video camera, a pulse oximeter, an optical navigation system, a location sensor, etc.). The one or more optical components may operate with a phase shift different from a phase shift of at least one of the plurality of power modulation signals.

FIG.7illustrates a block diagram of an exemplary method for powering one or more light sources of the disclosed lighting system, according to some aspects. The method700comprises a controller providing one or more input frequencies to an oscillator at step702. At step704, the oscillator may generate an input signal based on the input frequencies. The controller may generate a plurality of power modulation signals based on the input signal at step706. Two or more of the generated plurality of power modulation signals may have different phase shifts. At step708, the one or more power circuits may receive the plurality of power modulation signals and may generate one or more control signals to drive the light source(s).

During at least one modulation period, the phase shift of at least one of the plurality of power modulation signals may be different from the phase shift of another one of the plurality of power modulation signals and/or from a signal causing the operation of one or more optical components. The different phase shifts may be associated with different channels for driving one or more different light sources. This difference (including the variation) in one or more phase shifts may reduce or eliminate the amount of interference between the light sources in the lighting system and/or the optical component(s). In some aspects, the different phase shifts may lead to asynchronous driving of the plurality of channels.

Examples of the disclosure may comprise powering one or more light sources using a lighting system comprising a plurality of oscillators. The lighting system may be, e.g., light system400comprising a plurality of oscillators420.FIG.8illustrates a block diagram of an exemplary method for powering one or more light sources of the disclosed lighting system, according to some aspects. The method800comprises a controller providing one or more input frequencies to a plurality of oscillators at step802. The one or more input frequencies may be generated randomly or pseudo randomly. The plurality of oscillators may comprise at least one spread spectrum oscillator.

At step804, the plurality of oscillators may generate a plurality of input signals based on the one or more input frequencies. The input signal may be a clock signal, and the one or more input frequencies may be clock frequencies, for example. At step806, the controller may generate a plurality of power modulation signals, based on the plurality of input signals. In some aspects, the plurality of power modulation signals may have at least one property that differs from one another. For example, a first power modulation signal may have a first property, whereas a second power modulation signal may have a second property. Exemplary properties may include, but are not limited to, frequency, phase shift, delay, duty cycle, and power. The property may vary across modulation periods. The property (e.g., frequency, phase shift, or duty cycle) may vary or may be the same across modulation periods. In some aspects, the light source(s) may be driven using the same power during ON times of at least two modulation periods, or using different powers.

At step808, the one or more power circuits may receive the plurality of power modulation signals. The power circuit(s) may generate one or more control signals (step810) and may drive the one or more light sources using the one or more control signals (step812). The one or more control signals may be based on at least the plurality of power modulation signals, at least one or more linear signals, or both.

In some aspects, a converter (e.g., converter432) may provide one or more linear signals to the power circuits. The control signal(s) generated by the power circuit(s) may be further based on the linear signals. For example, when an input to or an output from (e.g., intensity level) the light source(s) is greater than or equal to a pre-determined level, the power circuit(s) may generate the control signal(s) based on the linear signal(s). Otherwise, the power circuit(s) may generate the control signal(s) based on the power modulation signal(s).

FIG.9illustrates an exemplary computing system, in accordance with some examples, that can be used for performing any of the methods described herein, including method500ofFIG.5, method700ofFIG.7, and method800ofFIG.8, and can be used for any of the systems described herein, including the lighting systems400and450ofFIGS.4A and4B. System900can be a computer connected to a network, which can be, for example, an operating room network or a hospital network. System900can be a client computer or a server. As shown inFIG.9, system900can be any suitable type of microcontroller or microprocessor-based system, such as an embedded control system, personal computer, workstation, server, or handheld computing device (portable electronic device) such as a phone or tablet. The system can include, for example, one or more of processors910, input device920, output device930, storage940, and communication device960. Input device920and output device930can generally correspond to those described above and can either be connectable or integrated with the computer.

Input device920can be any suitable device that provides input, such as a touch screen, keyboard or keypad, mouse, gesture recognition component of a virtual/augmented reality system, or voice-recognition device. Output device930can be or include any suitable device that provides output, such as a touch screen, haptics device, virtual/augmented reality display, or speaker.

Storage940can be any suitable device that provides storage, such as an electrical, magnetic, or optical memory including a RAM, cache, hard drive, removable storage disk, or other non-transitory computer readable medium. Communication device960can include any suitable device capable of transmitting and receiving signals over a network, such as a network interface chip or device. The components of the computer can be connected in any suitable manner, such as via a physical bus or wirelessly.

Software950, which can be stored in storage940and executed by processor910, can include, for example, the programming that embodies the functionality of the present disclosure (e.g., as embodied in the devices as described above). For example, software950can include one or more programs for performing one or more of the steps of the methods disclosed herein.

Software950can also be stored and/or transported within any non-transitory computer-readable storage medium for use by or in connection with an instruction execution system, apparatus, or device, such as those described above, that can fetch instructions associated with the software from the instruction execution system, apparatus, or device and execute the instructions. In the context of this disclosure, a computer-readable storage medium can be any medium, such as storage940, that can contain or store programming for use by or in connection with an instruction execution system, apparatus, or device.

Software950can also be propagated within any transport medium for use by or in connection with an instruction execution system, apparatus, or device, such as those described above, that can fetch instructions associated with the software from the instruction execution system, apparatus, or device and execute the instructions. In the context of this disclosure, a transport medium can be any medium that can communicate, propagate or transport programming for use by or in connection with an instruction execution system, apparatus, or device. The transport readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, or infrared wired or wireless propagation medium.

System900may be connected to a network, which can be any suitable type of interconnected communication system. The network can implement any suitable communications protocol and can be secured by any suitable security protocol. The network can comprise network links of any suitable arrangement that can implement the transmission and reception of network signals, such as wireless network connections, T1 or T3 lines, cable networks, DSL, or telephone lines.

System900can implement any operating system suitable for operating on the network. Software950can be written in any suitable programming language, such as C, C++, C #, Java, or Python. In various examples, application software embodying the functionality of the present disclosure can be deployed in different configurations, such as in a client/server arrangement or through a Web browser as a Web-based application or Web service, for example.

The foregoing description, for the purpose of explanation, has been described with reference to specific aspects. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The aspects were chosen and described in order to best explain the principles of the techniques and their practical applications. Others skilled in the art are thereby enabled to best utilize the techniques and various aspects with various modifications as are suited to the particular use contemplated.

Although the disclosure and examples have been fully described with reference to the accompanying figures, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the disclosure and examples as defined by the claims. Finally, the entire disclosure of the patents and publications referred to in this application are hereby incorporated herein by reference.