Systems and methods for controlled illumination of light-emitting diodes

Abstract

A system and method for controlled illumination of LEDs is disclosed. An exemplary system includes a plurality of LEDs, an LED controller, a current buffer adapted to receive an input bias level signal from the LED controller, where a set of LEDs to be controlled together are connected in parallel to the circuit with the current buffer, and at least one current-limiting resistor connected to the circuit with the plurality of LEDs and the current buffer. The system and method are adapted to control illumination of the LEDs by applying a constant voltage to the circuit based on the input bias level signal to control illumination of the light-emitting diodes without using pulse-width modulation. This avoids crosstalk interference with RFID components due to pulse-width modulation.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to systems and methods for controlled illumination of light-emitting diodes (LEDs). [Background technology]

[0002] Various ways of controlling the illumination of LEDs have been implemented for different applications. For example, in series control, several LEDs are connected in series and driven by a single LED driver. While the setup is simple, it can require high voltages, and failure of one LED in the array will cause the entire set to fail.

[0003] In another example, each LED is controlled separately, with each channel using a multi-channel LED driver. While this configuration allows for individual control, the control signals to the different channels may have a time delay, which can result in a time delay in the illumination of different LEDs that are intended to illuminate simultaneously.

[0004] Illumination of LEDs has been used, for example, in ophthalmic surgical systems. Illumination of LEDs has been used to indicate the status of an instrument port, such as whether the instrument port is available for a connected instrument, whether an instrument is properly connected to the instrument port, and whether a properly connected instrument is available for use. Exemplary systems for instrument identification and associated illumination are described and illustrated in U.S. Pat. Nos. 7,443,296 and 7,551,077, the entire disclosures of which are incorporated herein by reference. Such systems may use RFID tags on the instrument and radio frequency identification (RFID) antennas on the instrument port. Connection status may be determined from the RFID tag and indicated by the LED.

[0005] In some conventional systems, LEDs are controlled using pulse-width modulation. However, pulse-width modulation can cause crosstalk interference between the LED driver circuit and an RFID antenna located in close proximity to the LED driver circuit. Because RFID components are located close to the LED circuit, the higher harmonics of the pulse-width modulated signal can affect the RFID signal. Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, there remains a need for improved systems and methods for controlled illumination of LEDs. [Means for solving the problem]

[0007] The present disclosure relates to systems and methods for improved controlled illumination of LEDs.

[0008] In some exemplary embodiments, an equipment identification system for an ophthalmic surgery system comprises an RFID antenna, a plurality of LEDs, a light emitting diode controller, a current buffer connected to the light emitting diode controller and adapted to receive an input bias level signal from the light emitting diode controller, wherein the LEDs in the plurality of LEDs are connected in parallel to each other in a circuit with the current buffer, and at least one current-limiting resistor connected to the circuit with the plurality of LEDs and the current buffer, wherein the system is adapted to control illumination of the LEDs by applying a constant voltage to the circuit based on the input bias level signal to control illumination of the light emitting diodes without using pulse width modulation.

[0009] In some exemplary embodiments, the LEDs in the plurality of LEDs may be arranged in a ring. The RFID antenna may be circular. The LEDs in the plurality of LEDs may be arranged in a ring around the RFID antenna. The light emitting diode controller may include a digital-to-analog converter.

[0010] In some exemplary embodiments, the system includes multiple circuits of LEDs, with the LEDs connected in parallel to one another. The system may include one, two, three, or more such circuits of LEDs. In one example, a first plurality of LEDs in a first circuit may emit a first color, a second plurality of LEDs in a second circuit may emit a second color, and a third plurality of LEDs in a third circuit may emit a third color. For example, the first color, the second color, and the third color may be red, green, and blue, respectively.

[0011] In some exemplary embodiments, each light emitting diode has at least one dedicated current limiting resistor connected in series with that light emitting diode and in parallel with the remaining LEDs in the same circuit, hi some exemplary embodiments, at least one current limiting resistor is connected in series with all LEDs in the same circuit.

[0012] In some exemplary embodiments, a system for controlled illumination of LEDs comprises a plurality of LEDs; a light emitting diode controller; a current buffer connected to the light emitting diode controller and adapted to receive an input bias level signal from the light emitting diode controller, wherein the LEDs in the plurality of LEDs are connected in parallel with each other in a circuit with the current buffer; and at least one current-limiting resistor connected to the circuit with the plurality of LEDs and the current buffer, wherein the system is adapted to control illumination of the LEDs without using pulse width modulation.

[0013] In some exemplary embodiments, a method for controlled illumination of LEDs includes sending an input bias level signal from a light emitting diode controller to a current buffer, and providing a constant bias voltage level to a circuit including a plurality of LEDs based on the input bias level signal, wherein the LEDs in the circuit are connected in parallel with each other.

[0014] These and other examples will be apparent to those skilled in the art upon reading this disclosure.

[0015] The accompanying drawings illustrate several examples of the systems and methods disclosed herein and, together with the following detailed description, serve to explain the principles of the present disclosure. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a block diagram illustrating components of an exemplary system according to the present disclosure. [Figure 2] FIG. 2 is a schematic diagram illustrating components of an exemplary system according to the present disclosure. [Figure 3] FIG. 3 is a schematic diagram illustrating components of another exemplary system according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0017] The accompanying drawings can be better understood with reference to the following detailed description.

[0018] For the purposes of explaining the principles of the present disclosure, reference will be made to the drawings and specific language will be used to describe them. Nevertheless, it will be understood that reference to certain embodiments is not intended to limit the scope of the present disclosure. Any alternatives and further modifications to the described exemplary systems, devices, apparatus, and methods, and any further applications of the principles of the present disclosure, are fully contemplated as would normally occur to one skilled in the art to which this disclosure pertains. In particular, features, components, and / or steps described with respect to one embodiment of the present disclosure may be combined with features, components, and / or steps described with respect to other embodiments of the present disclosure, or may be modified and / or substituted as would normally occur to one skilled in the art. For simplicity, the same reference numbers may be used throughout the drawings in some instances to refer to the same or similar parts.

[0019] 1 is a block diagram illustrating components of an exemplary system according to the present disclosure. The system may be implemented as an equipment identification system for an ophthalmic surgical system that may be used for ophthalmic surgery, such as, for example, cataract surgery and / or retinal surgery. Except for the differences described herein, the ophthalmic surgical system may be similar to the ophthalmic surgical system shown and described in U.S. Pat. No. 9,931,447 (the entire disclosure of which is incorporated herein by reference) and / or similar to known and used ophthalmic surgical systems, such as the CENTURION® Vision System available from Alcon Laboratories, Inc. (Fort Worth, Texas) or the CONSTELLATION® Vision System available from Alcon Laboratories, Inc. (Fort Worth, Texas), or any other ophthalmic surgical system suitable for use with the principles described herein.

[0020] The ophthalmic surgery system may include an ophthalmic surgery console that houses a computer system and components for one or more ophthalmic surgery functions, a display screen, one or more external controls such as a foot switch, and a number of instruments that may be connected to the ophthalmic surgery console. The ophthalmic surgery console may have a fluidics cassette dock in which a fluidics cassette may be placed.

[0021] The instruments that may be connected to the ophthalmic surgery console may be for any of a variety of functions useful in ophthalmic surgery. For example, such instruments may include one or more ultrasound phacoemulsification instruments (e.g., instruments for removing cataract lenses), diathermy instruments, vitrectomy instruments, laser therapy instruments, lighting instruments, cutters, forceps, scissors, or any other type of instrument suitable for use in ophthalmic surgery.

[0022] An ophthalmic surgery console may have one or more instrument ports to which instruments may be connected. Each instrument port may be configured for a particular type of instrument.

[0023] Instruments connected to the ophthalmic surgery console may have connectors for connecting with appropriate instrument ports. The instrument connectors may have machine-readable information that can be read by a reader on the ophthalmic surgery console when the instrument is connected to the instrument port. For example, each instrument may have a radio frequency identification (RFID) tag, and each instrument port on the ophthalmic surgery console may have an associated RFID antenna for reading the RFID tag of the connected instrument. Each instrument port on the ophthalmic surgery console may also have an indicator, such as a light-emitting diode (LED) ring, to indicate the status of the particular port and / or instrument. For example, different colors or modes (e.g., steady on or flashing) of the LED may be used to indicate whether the instrument port is available for a connected instrument, whether the instrument is properly connected to the instrument port, whether a properly connected instrument is available for use, etc. Exemplary systems for instrument identification and associated illumination are described and illustrated in U.S. Pat. Nos. 7,443,296 and 7,551,077, the entire disclosures of which are incorporated herein by reference.

[0024] In Figure 1, the RFID tags of the equipment connected to the ophthalmic surgery console are represented as external RFID tag 32. The remaining elements of Figure 1 may be implemented within the ophthalmic surgery console itself.

[0025] The microcontroller 10 may be used to control the operation of reading the RFID tag and illuminating the LED. To read the RFID tag 32 of an instrument connected to the instrument port of the ophthalmic surgical console, the microcontroller 10 may communicate with the RFID reader 22 via the I2C bus 12. When instructed by the microcontroller 10, the RFID reader 22 transmits an RFID discovery signal via the RF circuitry 24 and the RFID antenna 30 to read the connected external RFID tag 32. The RFID antenna 30 is positioned on the instrument port adjacent to where the instrument's external RFID tag 32 will be located when the instrument is connected to the instrument port. The instrument's external RFID tag 32 is within detection range of the RFID antenna when the instrument is connected to the instrument port. The detection range may be, for example, about 10 mm to about 50 mm and may vary depending on the RF power of the RFID reader 22 and / or the design of the RFID antenna 30 or RFID tag 32.

[0026] When the RFID reader 22 detects an external RFID tag, information from the RFID tag is read by the RFID reader 22. The information is communicated to the microcontroller 10.

[0027] The microcontroller 10 receives and validates the external RFID tag information and then, based on the information, sends one or more control commands to an associated LED controller 42 to appropriately illuminate LEDs indicating the device port and / or device status. The microcontroller 10 may communicate with the LED controller 42 via the I2C bus 12. The LED controller 42 may include a digital-to-analog converter (DAC).

[0028] To illuminate the desired LEDs, the LED controller 42 sends a control voltage as an input bias level signal to the current buffer 44. The current buffer 44 may comprise a high current operational amplifier. The current buffer 44 receives the input bias level signal from the LED controller 42 and acts as a buffer to sink current from the parallel LEDs, as described in more detail below and in connection with FIGS. 2 and 3.

[0029] A plurality of LEDs 60 are connected to a circuit including a current buffer 44. At least one current-limiting resistor 46 is connected to a circuit including the plurality of LEDs 60 and the current buffer 44. In the illustrated example, red-green-blue (RGB) LEDs 60 are used. In practice, a single RGB LED 60 may include three LEDs: a red LED, a green LED, and a blue LED. In the illustrated example, a plurality of red LEDs are connected together to a first circuit including a current buffer 44, a plurality of green LEDs are connected together to a second circuit including a current buffer 44, and a plurality of blue LEDs are connected together to a third circuit including a current buffer 44. Other colors and sets of LEDs are possible.

[0030] In the illustrated example, the RGB LEDs 60 are arranged in a ring shape. The RFID antenna 30 may be circular, and the RGB LEDs 60 may be arranged in a ring shape around the RFID antenna 30.

[0031] In each circuit of LEDs, the LEDs in the circuit are connected in parallel with each other. The LEDs can be connected to the current-limiting resistor in several ways, as shown in Figures 2 and 3. While two ways are shown together in Figure 1, those skilled in the art will understand that only one of the two ways need be used.

[0032] In the first example, shown as parallel resistor mode 52 in Figure 1, each LED has at least one dedicated current-limiting resistor 54 connected in series with that LED and in parallel with the remaining LEDs in the same circuit, as shown schematically in Figure 2.

[0033] FIG. 2 is a schematic diagram illustrating components of an exemplary system according to the present disclosure. Multiple RGB LEDs 60 may be used together in any suitable number. The designation -1 through -n in the drawings is used to indicate the first through nth items of a set of items. In the example shown in FIG. 2, multiple red LEDs 60R-1 through 60R-n are connected together to a first circuit with a current buffer 44, multiple green LEDs 60G-1 through 60G-n are connected together to a second circuit with a current buffer 44, and multiple blue LEDs 60B-1 through 60B-n are connected together to a third circuit with a current buffer 44.

[0034] In the example of Figure 2, each LED has at least one dedicated current-limiting resistor connected in series with that LED and in parallel with the remaining LEDs in the same circuit. Each red LED 60R has at least one dedicated current-limiting resistor 54R connected in series with that red LED 60R and in parallel with the remaining red LEDs in the same circuit. For example, red LED 60R-1 has a dedicated current-limiting resistor 54R-1 connected in series with that red LED 60R-1 and in parallel with the remaining red LEDs in the same circuit, and red LED 60R-n has a dedicated current-limiting resistor 54R-n connected in series with that red LED 60R-n and in parallel with the remaining red LEDs in the same circuit. Each green LED 60G has at least one dedicated current-limiting resistor 54G connected in series with that green LED 60G and in parallel with the remaining green LEDs in the same circuit. For example, green LED 60G-1 has a dedicated current-limiting resistor 54G-1 connected in series with it and in parallel with the remaining green LEDs in the same circuit, and green LED 60G-n has a dedicated current-limiting resistor 54G-n connected in series with it and in parallel with the remaining green LEDs in the same circuit. Each blue LED 60B has at least one dedicated current-limiting resistor 54B connected in series with it and in parallel with the remaining blue LEDs in the same circuit. For example, blue LED 60B-1 has a dedicated current-limiting resistor 54B-1 connected in series with it and in parallel with the remaining blue LEDs in the same circuit, and blue LED 60B-n has a dedicated current-limiting resistor 54B-n connected in series with it and in parallel with the remaining blue LEDs in the same circuit.

[0035] In a second example, shown as series resistor mode 56 in Figure 1, at least one current-limiting resistor 58 is connected in series with every LED in the circuit, as shown schematically in Figure 3.

[0036] FIG. 3 is a schematic diagram illustrating components of another exemplary system according to the present disclosure. As shown in FIG. 2, multiple RGB LEDs 60 are used together in any suitable number, with the designation -1 through -n used to indicate the first through nth items of the set of items. Similar to the example of FIG. 2, in the example shown in FIG. 3, multiple red LEDs 60R-1 through 60R-n are connected together to a first circuit with a current buffer 44, multiple green LEDs 60G-1 through 60G-n are connected together to a second circuit with a current buffer 44, and multiple blue LEDs 60B-1 through 60B-n are connected together to a third circuit with a current buffer 44.

[0037] In the example of Figure 3, at least one current-limiting resistor is connected in series with every LED in the circuit. Each circuit of red LEDs 60R-1 to 60R-n has at least one current-limiting resistor 58R connected in series with every LED in that circuit. Each circuit of green LEDs 60G-1 to 60G-n has at least one current-limiting resistor 58G connected in series with every LED in that circuit. Each circuit of blue LEDs 60B-1 to 60B-n has at least one current-limiting resistor 58B connected in series with every LED in that circuit.

[0038] The current limiting resistor may be selected depending on the forward voltage of the LED. In one example, the forward voltage of a red LED is 2.0 V, and the forward voltage of a green or blue LED is 3.1 V. The limiting resistor is related to the forward voltage of the LED by the following equation: R (limiting resistor) = (V S (Supply voltage)-V f (LED forward voltage) / current

[0039] In use, the LED controller 42 sends an input bias level signal to the current buffer 44. The current buffer 44 receives the input bias level signal from the LED controller 42. Based on the input bias level signal, a constant voltage is applied to a circuit including multiple LEDs, for example, a circuit including multiple single-color LEDs. The current buffer 44 acts as a buffer to sink current from the parallel LEDs in the circuit.

[0040] Those skilled in the art will recognize that the systems and methods disclosed herein have one or more advantages over conventional approaches. For example, compared to conventional approaches, the systems and methods disclosed herein are adapted to control the illumination of LEDs without using pulse-width modulation. Among LED driving and dimming methods, methods such as pulse-width modulation can cause crosstalk between the LED driving circuit and a nearby RFID antenna. Because RFID components are located near the LED circuit, high-order harmonics of the pulse-width modulated signal can affect the RFID signal. Those skilled in the art will recognize that the systems and methods disclosed herein are adapted to control the illumination of LEDs without using pulse-width modulation and, as a result, without the crosstalk and interference that can be associated with pulse-width modulation.

[0041] Additionally, those skilled in the art will recognize that the systems and methods disclosed herein provide a simple and efficient method for controlling LED brightness through linear control. Conventional DACs may have a current limit of approximately 10 mA to 20 mA per port, which is insufficient to provide the high current sink required for multiple LEDs placed in parallel. Typical indicator LEDs have a forward current of 20 mA to 25 mA each. When multiple LEDs are placed in parallel, the required current sink may be approximately 100 mA to 200 mA. As disclosed herein, a current buffer provides a high current sink to facilitate lighting multiple LEDs without pulse width modulation. LEDs in a single circuit can be illuminated simultaneously and efficiently.

[0042] Those skilled in the art will recognize that the embodiments encompassed by the present disclosure are not limited to the specific exemplary embodiments described above. In this regard, while exemplary implementations have been shown and described, a wide range of modifications, changes, and substitutions to the foregoing disclosure are contemplated. It is to be understood that such variations can be made to the foregoing without departing from the scope of the present disclosure. Accordingly, it is appropriate that the appended claims be construed broadly and consistently with the present disclosure. According to aspect (1), there is provided an equipment identification system for an ophthalmic surgery system, the equipment identification system comprising: a radio frequency identification antenna; a plurality of light emitting diodes; a light emitting diode controller; a current buffer connected to the light emitting diode controller and adapted to receive an input bias level signal from the light emitting diode controller, the plurality of light emitting diodes being connected in parallel with one another in a circuit comprising the current buffer; at least one current-limiting resistor connected to the circuit comprising the plurality of light-emitting diodes and the current buffer; Equipped with the system is adapted to control the illumination of the light emitting diode by applying a constant voltage to the circuit based on the input bias level signal to control the illumination of the light emitting diode without using pulse width modulation. It is an equipment identification system. According to aspect (2), the light emitting diodes in the plurality of light emitting diodes are arranged in a ring shape. According to aspect (3), the radio frequency identification antenna is circular. According to aspect (4), the light emitting diodes in the plurality of light emitting diodes are arranged in a ring shape around the radio frequency identification antenna. According to aspect (5), the light-emitting diode controller includes a digital-to-analog converter. According to aspect (6), the plurality of light-emitting diodes connected in parallel to one another in a circuit are a first plurality of light-emitting diodes connected to a first circuit, The system further includes a second plurality of light emitting diodes connected in parallel to one another in a second circuit. According to aspect (7), the light emitting device further comprises a third plurality of light emitting diodes connected in parallel to each other in a third circuit. According to aspect (8), the first plurality of light-emitting diodes emit light of a first color, the second plurality of light-emitting diodes emit light of a second color, and the third plurality of light-emitting diodes emit light of a third color. According to aspect (9), the first color is red, the second color is green, and the third color is blue. According to aspect (10), the at least one current-limiting resistor includes a plurality of current-limiting resistors, and each light-emitting diode has at least one dedicated current-limiting resistor connected in series with the light-emitting diode and in parallel with the remaining light-emitting diodes in the same circuit. According to aspect (11), the at least one current-limiting resistor includes at least one current-limiting resistor connected in series with all of the light-emitting diodes in the plurality of light-emitting diodes. According to aspect (12), there is provided a system for controlled lighting of a light-emitting diode, the system comprising: a plurality of light emitting diodes; a light emitting diode controller; a current buffer connected to the light emitting diode controller and adapted to receive an input bias level signal from the light emitting diode controller, wherein the light emitting diodes in the plurality of light emitting diodes are connected in parallel with one another in a circuit comprising the current buffer; at least one current-limiting resistor connected to the circuit comprising the plurality of light-emitting diodes and the current buffer; Equipped with the system is adapted to control the illumination of the light emitting diode by applying a constant voltage to the circuit based on the input bias level signal to control the illumination of the light emitting diode without using pulse width modulation. It is a system. According to aspect (13), the light emitting diodes in the plurality of light emitting diodes are arranged in a ring shape. According to aspect (14), the light-emitting diode controller includes a digital-to-analog converter. According to aspect (15), the plurality of light-emitting diodes connected in parallel to one another in a circuit are a first plurality of light-emitting diodes connected to a first circuit, The system further includes a second plurality of light emitting diodes connected in parallel to one another in a second circuit. According to aspect (16), the light emitting device further comprises a third plurality of light emitting diodes connected in parallel to each other in a third circuit. According to aspect (17), the first plurality of light-emitting diodes emit light of a first color, the second plurality of light-emitting diodes emit light of a second color, and the third plurality of light-emitting diodes emit light of a third color. According to aspect (18), the at least one current-limiting resistor includes a plurality of current-limiting resistors, and each light-emitting diode has at least one dedicated current-limiting resistor connected in series with the light-emitting diode and in parallel with the remaining light-emitting diodes in the same circuit. According to aspect (19), the at least one current-limiting resistor includes at least one current-limiting resistor connected in series with all of the light-emitting diodes in the plurality of light-emitting diodes. According to aspect (20), there is provided a method for controlled lighting of a light-emitting diode, the method comprising: sending an input bias level signal from the light emitting diode controller to the current buffer; applying a constant voltage to a circuit including a plurality of light emitting diodes based on the input bias level signal, the light emitting diodes in the circuit being connected in parallel with each other; Including, method.

Claims

1. 1. An equipment identification system for an ophthalmic surgical system, the equipment identification system comprising: an RFID (radio frequency identification) antenna; a plurality of light emitting diodes; a light emitting diode controller; an RFID reader connected to the RFID antenna; a microcontroller connected to the light emitting diode controller and the RFID reader, the microcontroller being programmed to receive and verify information from the RFID reader and to send control commands to the light emitting diode controller based on the received and verified information; a current buffer connected to the light emitting diode controller and adapted to receive an input bias level signal from the light emitting diode controller, the plurality of light emitting diodes being connected in parallel with one another in a circuit comprising the current buffer; a plurality of current limiting resistors connected to the circuit including the plurality of light emitting diodes and the current buffer; Equipped with the equipment identification system is adapted to control the illumination of the light emitting diode by applying a constant voltage to the circuit based on the input bias level signal to control the illumination of the light emitting diode without using pulse width modulation; each of the plurality of light emitting diodes has at least one dedicated current limiting resistor from the plurality of current limiting resistors, the at least one dedicated current limiting resistor being connected in series with the light emitting diode and in parallel with the remaining light emitting diodes in the same circuit; each of the at least one dedicated current-limiting resistors is selected based on a light-emitting diode forward voltage of a corresponding light-emitting diode connected in series with the dedicated current-limiting resistor; An equipment identification system for ophthalmic surgery systems.

2. The instrument identification system for an ophthalmic surgical system of claim 1 , wherein the light emitting diodes in the plurality of light emitting diodes are arranged in a ring.

3. The instrument identification system for an ophthalmic surgical system of claim 1 , wherein the RFID antenna is circular.

4. The instrument identification system for an ophthalmic surgical system of claim 1 , wherein the light emitting diodes in the plurality of light emitting diodes are arranged in a ring shape around the RFID antenna.

5. The instrument identification system for an ophthalmic surgical system of claim 1 , wherein the light emitting diode controller comprises a digital-to-analog converter.

6. the plurality of light emitting diodes connected in parallel to one another in the circuit are a first plurality of light emitting diodes connected in a first circuit; the equipment identification system further comprising a second plurality of light emitting diodes connected in parallel to one another in a second circuit; 10. An instrument identification system for an ophthalmic surgical system according to claim 1.

7. The instrument identification system for an ophthalmic surgical system of claim 6 , further comprising a third plurality of light emitting diodes connected in parallel to one another in a third circuit.

8. 8. The instrument identification system for an ophthalmic surgical system of claim 7, wherein the first plurality of light emitting diodes emit a first color, the second plurality of light emitting diodes emit a second color, and the third plurality of light emitting diodes emit a third color.

9. The instrument identification system for an ophthalmic surgical system of claim 8 , wherein the first color is red, the second color is green, and the third color is blue.

10. 1. A method for controlled illumination of light emitting diodes, said method comprising: receiving and verifying information from an RFID (radio frequency identification) reader connected to an RFID antenna in the microcontroller; sending a control command from the microcontroller to a light emitting diode controller based on the received and verified information; sending an input bias level signal from the light emitting diode controller to a current buffer; applying a constant voltage to a circuit including a plurality of light emitting diodes based on the input bias level signal, the light emitting diodes in the circuit being connected in parallel with each other; Including, each of the plurality of light emitting diodes has at least one dedicated current limiting resistor connected in series with the light emitting diode and in parallel with the remaining light emitting diodes in the same circuit; each of the at least one dedicated current-limiting resistors is selected based on a light-emitting diode forward voltage of a corresponding light-emitting diode connected in series with the dedicated current-limiting resistor; method.

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